CN114696590A - Electrical equipment, power factor compensation circuit and control device and control method thereof - Google Patents

Abstract

The invention discloses an electric appliance, a power factor compensation circuit, a control device and a control method thereof. The control device of the power factor compensation circuit comprises: the first voltage sampling module is used for sampling the voltage of an inductance coil in the power factor compensation circuit and outputting a first voltage sampling signal; the second voltage sampling module is used for sampling the voltage of the alternating current accessed by the power factor compensation circuit and outputting a first waveform signal with the same frequency and the same phase as the alternating current; and the switch driving signal generating module is used for generating a switch driving signal according to the first voltage sampling signal and the first waveform signal and outputting the switch driving signal to a controlled end of a switch circuit in the power factor compensation circuit so as to control the switching frequency of the switch circuit. According to the technical scheme, when the inductive voltage corresponding to the input current in the PFC inductive coil exceeds the upper limit of the preset voltage range in the CCM, the PFC circuit can continue to work according to the higher input current.

Description

Electrical equipment, power factor compensation circuit and its control device and control method

technical field

The invention relates to the technical field of power conversion, in particular to an electrical device, a power factor compensation circuit and a control device and control method thereof.

Background technique

A PFC (Power Factor Compensation) circuit is usually used in electrical equipment to improve the quality of the output voltage while boosting/bucking the connected commercial power. At present, there are three working modes in the PFC circuit, namely DCM (current discontinuous mode), BCM (current critical mode) and CCM (current continuous mode). The PFC circuit will switch the above three working modes according to the change of the input current in the coil. , when the amplitude range of the input current is small, it works in DCM, and when the input current increases, it will switch to BCM and CCM step by step.

If the PFC (power factor compensation) circuit is already in CCM, when the voltage corresponding to the input current in the PFC inductor exceeds the upper limit of the voltage range preset in the CCM, the mode cannot be switched to meet the higher input current requirements.

SUMMARY OF THE INVENTION

The main purpose of the present invention is to provide a control device for a power factor compensation circuit, which is designed to keep the PFC circuit according to a higher voltage range when the inductance voltage corresponding to the input current in the PFC inductance coil exceeds the upper limit of the voltage range preset in the CCM. input current to work.

In order to achieve the above object, the present invention provides a control device of a power factor compensation circuit. The control device of the power factor compensation circuit includes:

a first voltage sampling module, configured to perform voltage sampling on the voltage of the inductor coil in the power factor compensation circuit, and output a first voltage sampling signal;

a second voltage sampling module, configured to perform voltage sampling on the alternating current connected to the power factor compensation circuit, and output a first waveform signal having the same frequency and the same phase as the alternating current; and

A switch drive signal generation module, configured to generate a switch drive signal according to the first voltage sampling signal and the first waveform signal, and output it to the controlled end of the switch circuit in the power factor compensation circuit to control the switch the switching frequency of the circuit.

Optionally, the switch drive signal generation module includes:

The first duty cycle calculation module is used to obtain a preset inductance value, a preset switching frequency, a voltage value corresponding to the first voltage sampling signal, and a voltage amplitude of the first waveform signal, and is used to calculate the The preset inductance value, the preset switching frequency and the voltage amplitude of the first waveform signal are multiplied and calculated, and then the voltage value corresponding to the first voltage sampling signal is divided and calculated, and the first voltage value is output according to the calculation result. duty cycle signal; and

The first switch drive signal output module is configured to output the switch drive signal according to the preset pulse amplitude and the received first duty cycle signal.

Optionally, the switch drive signal generation module includes:

a first current sensor, used for sampling the alternating current connected to the power factor compensation circuit, and outputting a current sampling signal;

a current compensation circuit, configured to output a second waveform signal according to the first waveform signal and the current sampling signal;

The second duty cycle calculation module is used to obtain the preset inductance value, the preset switching frequency, the voltage value corresponding to the first voltage sampling signal and the voltage amplitude of the second waveform signal, and is used to calculate the The preset inductance value, the preset switching frequency and the voltage amplitude of the second waveform signal are multiplied and calculated, and then the voltage value corresponding to the first voltage sampling signal is divided and calculated, and a second voltage value is output according to the calculation result. duty cycle signal; and

The second switch driving signal output module is configured to output the switch driving signal according to the preset pulse amplitude and the received second duty cycle signal.

Optionally, the current compensation circuit is configured to obtain the absolute value of the average value of the amplitude of the current sampling signal within a preset time and the absolute value of the amplitude of the first waveform signal within the preset time, Subtract the absolute value of the amplitude of the first waveform signal and the absolute value of the average value within the preset time, and output a second waveform signal to the second duty cycle calculation module according to the calculation result .

Optionally, each cycle of the alternating current connected to the power factor compensation circuit is divided into a first half-wave cycle and a second half-wave cycle, and the preset time is the first half-wave cycle or the second half-wave cycle. cycle;

The current compensation circuit is configured to obtain the absolute value of the average value of the amplitude of the current sampling signal in the first half-wave cycle or the second half-wave cycle.

Optionally, the first voltage sampling module includes:

a first voltage sensor for detecting the voltage at the first end of the inductance coil and outputting a second voltage sampling signal;

a second voltage sensor for detecting the voltage at the second end of the inductive coil and outputting a third voltage sampling signal; and

The calculation circuit is configured to perform a subtraction calculation on the second voltage sampling signal and the third voltage sampling signal, and output a first voltage sampling signal according to the calculation result.

Optionally, the first waveform signal is a sine wave signal, and the switch driving signal is a PWM control signal.

The present invention also provides a control method for a power factor compensation circuit. The power factor compensation circuit includes an inductance coil for connecting to alternating current through a rectifier circuit and a switch circuit for controlling the direct current output from the rectifier circuit to the inductance coil according to a switch drive signal, The control method of the power factor compensation circuit includes the following steps:

performing voltage sampling on the inductor coil in the power factor compensation circuit to obtain a first voltage sampling signal;

performing voltage sampling on the alternating current connected to the power factor compensation circuit to obtain a first waveform signal having the same frequency and the same phase as the alternating current; and

A switch driving signal is output to the switch circuit according to the first voltage sampling signal and the first waveform signal, so as to control the switching frequency of the switch circuit.

Optionally, the step of outputting a switch driving signal to the switch circuit according to the first voltage sampling signal and the first waveform signal to control the switching frequency of the switch circuit includes:

determining a voltage value corresponding to the first voltage sampling signal and a voltage amplitude value of the first waveform signal;

计算获取第一占空比参数，并根据第一占空比参数生成第一占空比信号；D1为第一占空比参数，L为预设电感值，fsw为预设开关频率，I_Lon1为第一波形信号的电压幅值，Vi-V0为第一电压采样信号对应的电压值；以及According to the preset inductance value, the preset switching frequency, the voltage value corresponding to the first voltage sampling signal, the voltage amplitude of the first waveform signal, and the first preset formula:

Calculate and obtain the first duty cycle parameter, and generate the first duty cycle signal according to the first duty cycle parameter; D1 is the first duty cycle parameter, L is the preset inductance value, fsw is the preset switching frequency, I _Lon1 is the voltage amplitude of the first waveform signal, and Vi-V0 is the voltage value corresponding to the first voltage sampling signal; and

The switch driving signal is generated according to the preset pulse amplitude and the first duty cycle signal, and output to the switch circuit in the power factor compensation circuit to control the switching frequency of the switch circuit.

Optionally, the step of outputting a switch driving signal to the switch circuit according to the first voltage sampling signal and the first waveform signal to control the switching frequency of the switch circuit includes:

Perform current sampling on the alternating current connected to the power factor compensation circuit to obtain the current sampling signal;

obtaining a second waveform signal according to the first waveform signal and the current sampling signal;

determining a voltage value corresponding to the first voltage sampling signal and a voltage amplitude value of the second waveform signal;

计算获取第二占空比参数，并根据第二占空比参数生成第二占空比信号；D2为第二占空比参数，L为预设电感值，fsw为预设开关频率，I_Lon2为第二波形信号的电压幅值，Vi-V0为第一电压采样信号对应的电压值；According to the preset inductance value, the preset switching frequency, the voltage value corresponding to the first voltage sampling signal, the voltage amplitude of the second waveform signal, and the second preset formula:

Calculate and obtain the second duty cycle parameter, and generate the second duty cycle signal according to the second duty cycle parameter; D2 is the second duty cycle parameter, L is the preset inductance value, fsw is the preset switching frequency, I _Lon2 is the voltage amplitude of the second waveform signal, and Vi-V0 is the voltage value corresponding to the first voltage sampling signal;

The switch driving signal is generated according to the preset pulse amplitude and the second duty cycle signal, and is output to the switch circuit in the power factor compensation circuit to control the switching frequency of the switch circuit.

Optionally, the obtaining of the second waveform signal according to the first waveform signal and the current sampling signal is specifically:

Obtain the absolute value of the average value of the amplitude of the current sampling signal within the preset time and the absolute value of the amplitude of the first waveform signal within the preset time, and set the first waveform signal at the preset time The absolute value of the inner amplitude and the absolute value of the average value are subtracted, and a second waveform signal is generated according to the calculation result; wherein, each cycle of the alternating current connected to the power factor compensation circuit is divided into a first half-wave period and the second half-wave period, and the preset time is the first half-wave period or the second half-wave period.

Optionally, the step of performing voltage sampling on the inductor coil in the power factor compensation circuit to obtain the first voltage sampling signal includes:

performing voltage detection on the voltage at the first end of the inductance coil to obtain a second voltage sampling signal;

performing voltage detection on the voltage at the second end of the inductance coil to obtain a third voltage sampling signal;

The second voltage sampling signal and the third voltage sampling signal are subtracted, and a first voltage sampling signal is generated according to the calculation result.

The present invention also provides a power factor compensation circuit, the power factor compensation circuit includes:

DC output;

The inductance coil is used for connecting with the AC input terminal through the rectifier circuit, so as to output the DC power output after rectification by the rectifier circuit to the DC output terminal;

a switch circuit for controlling the direct current output from the rectifier circuit to the inductor coil according to the switch drive signal; and

The control device of the power factor compensation circuit as described above, the control device of the power factor compensation circuit is respectively connected with the AC input end, the inductance coil and the switch circuit; or, the power factor as described above is used Control method of compensation circuit.

The present invention also provides an electrical device, which includes the power factor compensation circuit as described above.

The technical solution of the present invention is to construct a control device for configuring a power factor compensation circuit by adopting a first voltage sampling module, a second voltage sampling module and a switch driving signal generating module. The first voltage sampling module is used for voltage sampling of the voltage of the inductor coil in the power factor compensation circuit, and outputs the first voltage sampling signal, and the second voltage sampling module is used for voltage sampling of the alternating current connected to the power factor compensation circuit , and output the first waveform signal with the same frequency and the same phase as the alternating current; the switch drive signal generation module is used to generate the switch drive signal according to the first voltage sampling signal and the first waveform signal, and output it to the switch in the power factor compensation circuit The controlled end of the circuit is used to control the switching frequency of the switching circuit, and then adjust the magnitude of the direct current output from the rectifier circuit to the inductance coil, so as to realize the function of power factor compensation. The control device of the power factor compensation circuit of the present invention generates the switch driving signal in real time according to the voltage of the inductance coil and the alternating current connected to the power factor compensation circuit, so as to control the switching frequency of the switch circuit in the power factor compensation circuit in real time, without the need of advance Three working modes of DCM, BCM and CCM are set, so even when the inductor voltage corresponding to the input current in the PFC inductor coil exceeds the upper limit of the preset voltage range in the CCM, the corresponding real-time switch drive signal can be generated to control the switch circuit to work. In turn, the PFC (power factor compensation circuit) can work according to a higher upper limit of the input current.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can also be obtained according to the structures shown in these drawings without creative efforts.

1 is a schematic diagram of functional modules of an embodiment of a control device for a power factor compensation circuit according to the present invention;

2 is a schematic diagram of functional modules of another embodiment of a control device for a power factor compensation circuit according to the present invention;

3 is a schematic diagram of functional modules of another embodiment of a control device for a power factor compensation circuit according to the present invention;

FIG. 4 is a schematic flow chart of a control method of a power factor compensation circuit according to an embodiment of the present invention;

FIG. 5 is a schematic flow chart of another embodiment of a control method for a power factor compensation circuit according to the present invention;

FIG. 6 is a schematic flow chart of another embodiment of a control method for a power factor compensation circuit according to the present invention;

FIG. 7 is a schematic flow chart of another embodiment of a control method for a power factor compensation circuit according to the present invention;

FIG. 8 is a schematic flow chart of another embodiment of a control method for a power factor compensation circuit according to the present invention;

FIG. 9 is a schematic diagram of a circuit structure of an embodiment of a power factor compensation circuit of the present invention.

Description of reference numbers:

The realization, functional characteristics and advantages of the present invention will be further described with reference to the accompanying drawings in conjunction with the embodiments.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relationship between various components under a certain posture (as shown in the accompanying drawings). The relative positional relationship, the movement situation, etc., if the specific posture changes, the directional indication also changes accordingly.

In the present invention, unless otherwise expressly specified and limited, the terms "connected", "fixed" and the like should be understood in a broad sense, for example, "fixed" may be a fixed connection, a detachable connection, or an integrated; It can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be an internal communication between two elements or an interaction relationship between the two elements, unless otherwise explicitly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

In addition, descriptions such as "first", "second", etc. in the present invention are only for descriptive purposes, and should not be construed as indicating or implying their relative importance or implicitly indicating the number of indicated technical features. Thus, a feature delimited with "first", "second" may expressly or implicitly include at least one of that feature. In addition, the technical solutions between the various embodiments can be combined with each other, but must be based on the realization by those of ordinary skill in the art. When the combination of technical solutions is contradictory or cannot be realized, it should be considered that the combination of such technical solutions does not exist. , is not within the scope of protection required by the present invention.

The invention provides a control device for a power factor compensation circuit, which can be applied to the power factor compensation circuit. The power factor compensation circuit may include an inductor coil and a switch circuit. The input end of the inductance coil can be connected to the AC input end through a rectifier circuit, and the rectifier circuit is used to rectify the alternating current connected to the AC input end into direct current and output it; and the input end of the switch circuit can be set between the inductance coil and the rectifier circuit. The output terminal can be grounded, and the controlled terminal can be connected to the control device of the power factor compensation circuit of the present invention, so as to ground the DC power output by the rectifier circuit when it is turned on. Therefore, the switch circuit can The driving signal is continuously turned on/off to realize the boost/buck regulation effect of pulse width modulation. This embodiment is explained by taking the switching circuit to realize the regulation effect of reducing the voltage as an example.

1 to 3, in an embodiment of the present invention, the control device of the power factor compensation circuit includes:

The first voltage sampling module 10 is configured to perform voltage sampling on the voltage of the inductor coil 50 in the power factor compensation circuit, and output a first voltage sampling signal;

The second voltage sampling module 20 is configured to perform voltage sampling on the alternating current connected to the power factor compensation circuit, and output a first waveform signal having the same frequency and the same phase as the alternating current; and

A switch driving signal generating module 30 is configured to generate a switch driving signal according to the first voltage sampling signal and the first waveform signal, and output it to the controlled end of the switch circuit 60 in the power factor compensation circuit to control the the switching frequency of the switching circuit 60.

In this embodiment, the first voltage sampling module 10 may be a voltage detection circuit constructed by a voltage dividing resistor, a voltage sensor device, or a dedicated coil voltage measurement device. When direct current flows through the inductance coil 50, the resistance of the inductance coil 50 will cause a voltage difference across the inductance coil 50, that is, the voltage of the inductance coil 50; and the first voltage sampling module 10 can adopt the principle of resistance division, thermoelectric conversion The real-time voltage of the inductor coil 50 can be acquired by means of , magneto-electric conversion, etc., and a first voltage sampling signal representing the real-time voltage can be generated according to the acquired real-time voltage.

The second voltage sampling module 20 may be implemented by using an AC voltage measuring device such as a voltage detection circuit, an AC voltage sensor, etc., and in combination with a waveform generating unit. The second voltage sampling module 20 can perform voltage sampling on the AC power connected to the power factor compensation circuit through the AC voltage measuring device and output the corresponding voltage sampling signal to the waveform generating unit, and can run the hardware circuit integrated in the waveform generating unit by running the voltage sampling module 20. and software program or algorithm to obtain the frequency and phase of the alternating current corresponding to the voltage sampling signal. For example, the waveform generation unit can convert the voltage sampling signal of the analog signal into a digital signal, and then run the frequency and phase analysis program to obtain the voltage sampling The frequency and phase of the alternating current corresponding to the signal can also be used to generate a first waveform signal with the same frequency and phase according to the acquired frequency and phase through a corresponding waveform generation circuit or software program. The first waveform signal may be one or more combinations of periodic signals such as a sine wave signal, a triangular wave signal, a sawtooth wave signal, or a square wave signal. It can be understood that the voltage sampling signal itself represents the real-time voltage value of the alternating current, so the real-time voltage value of the alternating current can be calculated according to the voltage sampling signal, and then its frequency and phase can be obtained.

The switch driving signal generating module 30 may be implemented by a microprocessor such as MCU, DSP or FPGA, or a dedicated control chip. A variety of preset software programs or algorithms and data may be integrated in the switch driving signal generation module 30, so that when the first voltage sampling signal and the first waveform signal are received, the two voltages can be obtained by running the corresponding software programs or algorithms respectively. information represented by each of them. It can be understood that the first waveform can be represented by the standard alternating current of the alternating current connected to the rectifier circuit 70; and the first voltage sampling signal can be represented by the voltage across the inductor coil 50, including the voltage flowing into the inductor coil 50 and the output of the inductor coil 50. voltage. It can also be understood that the voltage flowing into the inductance coil 50 may be a voltage adjusted by the switch circuit 60 , and the output end of the inductance coil 50 may be connected to the output end of the power factor compensation circuit. Therefore, the switch driving signal generation module 30 can be based on the standard AC power of the AC power connected to the rectifier circuit 70 , the voltage output to the inductor coil 50 after adjustment by the switch circuit 60 , the voltage consumed by the inductor coil 50 (and the voltage of the inductor coil 50 ), and The voltage output by the inductor coil 50 is used to generate a switch control signal in real time to control the on/off frequency (ie switching frequency) of the switch circuit 60, so that the rectifier circuit 70 rectifies the output DC power through the adjustment of the switch circuit 60 and the inductor coil 50. After consumption, the DC voltage of the corresponding size can be output to the output end of the power factor compensation circuit, so as to realize the effect of power factor compensation.

The technical solution of the present invention is to construct a control device for configuring a power factor compensation circuit by using the first voltage sampling module 10 , the second voltage sampling module 20 and the switch driving signal generating module 30 . Wherein, the first voltage sampling module 10 is used for voltage sampling of the voltage of the inductor coil 50 in the power factor compensation circuit, and outputs the first voltage sampling signal, and the second voltage sampling module 20 is used for the AC power connected to the power factor compensation circuit. performing voltage sampling, and outputting a first waveform signal with the same frequency and phase as the alternating current; the switch driving signal generating module 30 is configured to generate a switching driving signal according to the first voltage sampling signal and the first waveform signal, and output to the power factor The controlled end of the switch circuit 60 in the compensation circuit is used to control the switching frequency of the switch circuit 60, thereby adjusting the magnitude of the direct current output from the rectifier circuit 70 to the inductor coil 50, so as to realize the function of power factor compensation. The control device of the power factor compensation circuit of the present invention generates the switch driving signal in real time according to the voltage of the inductance coil 50 and the alternating current connected to the power factor compensation circuit, so as to control the switching frequency of the switch circuit 60 in the power factor compensation circuit in real time, There is no need to set the three operating modes of DCM, BCM and CCM in advance, so even when the inductor voltage corresponding to the input current in the PFC inductor coil 50 exceeds the upper limit of the voltage range preset in the CCM, the corresponding real-time switch drive signal can be generated to control the switch The circuit 60 operates so that the PFC (power factor compensation circuit) can operate according to a higher upper limit of the input current.

In addition, the present application also proposes a method of increasing the coil size and increasing the on-voltage of each switching device by applying external force when the inductor voltage corresponding to the input current in the PFC inductor coil exceeds the upper limit of the preset voltage range in the CCM to make the PFC The assumption that the circuit can continue to work at the switching frequency of the original CCM. However, applying an external force to increase the coil cannot be practically applied, and increasing the on-voltage of each switching device will cause irreversible damage to the switching device. However, the technical solution of the present application can not only be directly applied in practice, but also avoid the above-mentioned problems.

1 to 3 , in an embodiment of the present invention, the switch driving signal generating module 30 includes:

The first duty cycle calculation module 31 is used to obtain the preset inductance value, the preset switching frequency, the voltage value corresponding to the first voltage sampling signal and the voltage amplitude of the first waveform signal, and is used to calculate the The preset inductance value, the preset switching frequency and the voltage amplitude of the first waveform signal are multiplied and then divided with the voltage value corresponding to the first voltage sampling signal, and the first voltage value is output according to the calculation result. a duty cycle signal; and

The first switch driving signal output module 32 is configured to output the switch driving signal according to the preset pulse amplitude and the received first duty cycle signal.

In this embodiment, the first duty cycle calculation module 31 may be composed of a memory, a processor, a calculator and a signal generation unit. The preset inductance value can be the inductance value of the inductance coil 50, which can be measured in advance and stored in the first duty cycle module by those skilled in the art; the preset switching frequency can be a common switching frequency obtained through pre-experiments or can also be is the real-time switching frequency of the switching circuit 60 obtained through the switching frequency calculation module; the voltage value corresponding to the first voltage sampling signal can be obtained by running the hardware circuit/software analysis after converting the first voltage sampling signal through analog-to-digital conversion; the first waveform signal The voltage amplitude of is the real-time signal value of the first waveform signal, which is also obtained by running the hardware circuit/software analysis after analog-to-digital conversion. The first duty cycle calculation module 31 can divide the calculation result obtained by multiplying the first, second, and fourth with the third, that is, the voltage value corresponding to the first voltage sampling signal, to perform division calculation, It can be understood that the calculation result is represented as the duty cycle of the switch drive signal required by the switch circuit 60 at this time; the first duty cycle calculation module 31 can also generate a first duty cycle representing the duty cycle through the signal generating unit. The ratio signal is output to the first switch driving signal output module 32 .

The first switch drive signal output module 32 can be implemented by a memory, a processor and related hardware circuits; the switch drive signal can be a PWM signal. The memory may store preset relevant data and a software program or algorithm for analyzing and generating the switch driving signal. The first switch driving signal output module 32 can obtain the duty cycle represented by the first duty cycle signal by running an analysis software program or algorithm, and can call the pre-stored amplitude value and the duty cycle represented by the first duty cycle signal. A switch driving signal with corresponding amplitude and duty cycle is generated and output to the switch circuit 60 in the power factor compensation circuit. The technical solution of the present invention is to set the first duty ratio calculation module 31 and the first switch drive signal output module 32 to obtain the real-time first duty cycle first according to the first voltage sampling signal, the first waveform signal and various preset parameter data. The duty cycle signal is then generated according to the real-time first duty cycle signal and outputs a real-time switch driving signal to control the operation of the switch circuit 60. Compared with the control using each work mode, the preset voltage of each work mode can be connected to the line. The shackles, and because of the real-time control, is conducive to the power factor compensation effect of the PFC circuit.

1 to 3 , in an embodiment of the present invention, the switch driving signal generating module 30 includes:

The first current sensor 33 is used to perform current sampling on the alternating current connected to the power factor compensation circuit, and output a current sampling signal;

a current compensation circuit 34, configured to output a second waveform signal according to the first waveform signal and the current sampling signal;

The second duty cycle calculation module 35 is used to obtain the preset inductance value, the preset switching frequency, the voltage value corresponding to the first voltage sampling signal and the voltage amplitude of the second waveform signal, and is used to calculate the The preset inductance value, the preset switching frequency and the voltage amplitude of the second waveform signal are multiplied and then divided with the voltage value corresponding to the first voltage sampling signal, and the first voltage value is output according to the calculation result. two duty cycle signals; and

The second switch driving signal output module 36 is configured to output the switch driving signal according to the preset pulse amplitude and the received second duty cycle signal.

In this embodiment, the first current sensor 33 can be implemented by using a current-type Hall device to perform real-time current sampling on the alternating current connected to the power factor compensation circuit by means of magneto-electric conversion, etc., and output a current sampling of a corresponding size Signal.

The current compensation circuit 34 can be constructed by using hardware circuits used for calculation, such as a memory, a low-pass filter circuit, and a subtractor. It can be understood that the current sampling signal represents the real-time current value of the alternating current, the first waveform signal represents the real-time voltage value of the alternating current, and the current compensation circuit 34 can determine the relevant current parameters of the alternating current according to the two, such as amplitude, period. and phase and other parameters, and can output a second waveform signal representing the standard alternating current according to the determined result and the current value/voltage value represented by the two.

The specific implementation manner of the second duty ratio calculation module 35 may be the same as that of the above-mentioned first duty ratio calculation module 31 , wherein each preset data (preset inductance value and preset switching frequency) and the voltage value corresponding to the first voltage sampling signal It can also be obtained in the same manner as in the above-mentioned first duty ratio calculation module 31 , and details are not repeated here. The second duty cycle calculation module 35 can also use the corresponding software program or algorithm to multiply the preset inductance value, the preset switching frequency and the voltage amplitude of the second waveform signal, and then calculate the value corresponding to the first voltage sampling signal. The voltage value is divided and calculated, and the calculation result at this time can also be characterized as the duty cycle of the switch drive signal required by the switch circuit 60 at this time. The second duty cycle calculation module 35 can also generate a signal generation unit to represent the duty cycle. and output the second duty cycle signal to the second switch driving signal output module 36 .

The second switch drive signal output module 36 can also be consistent with the above-mentioned first switch drive signal output module 32, and the duty cycle represented by the second duty cycle signal can be obtained by running an analysis software program or algorithm, and can be pre-set by calling The stored amplitude value and the duty cycle represented by the second duty cycle signal are used to generate a switch drive signal having the corresponding amplitude value and duty cycle, and output it to the switch circuit 60 in the power factor compensation circuit. This embodiment is a parallel embodiment using the first duty ratio calculation module 31 and the first switch driving signal output module 32, and its beneficial effects are the same, which will not be repeated here; and both embodiments are obtained by obtaining The first waveform signal or the second waveform signal representing the standard alternating current is used to output the real-time switching drive signal, so that the applied power factor compensation circuit will not affect the power factor compensation circuit even if the input alternating current is not the standard current waveform. Compensation effect.

Referring to FIGS. 1 to 3 , in an embodiment of the present invention, the current compensation circuit 34 is configured to obtain the absolute value of the average value of the amplitude of the current sampling signal within a preset time and the first waveform signal at The absolute value of the amplitude within the preset time is calculated by subtracting the absolute value of the amplitude of the first waveform signal within the preset time and the absolute value of the average value, and outputting the second waveform according to the calculation result. The waveform signal is sent to the second duty cycle calculation module 35 .

Further, each cycle of the AC power connected to the power factor compensation circuit is divided into a first half-wave cycle and a second half-wave cycle, and the preset time is the first half-wave cycle or the second half-wave cycle. ;

The current compensation circuit 34 is configured to obtain the absolute value of the average value of the amplitude of the current sampling signal in the first half-wave cycle or the second half-wave cycle.

In this embodiment, the current compensation circuit 34 may be provided with a filter circuit such as a pass filter circuit and a subtractor. The current compensation circuit 34 can output the current sampling signal to the low-pass filter circuit, and the output signal after filtering is represented as the average value of the signal in a preset time, and the average value can be calculated by taking the absolute value output to the negative input terminal of the subtractor; and the current compensation circuit 34 can also output the first waveform signal connected to the positive input terminal of the subtractor after taking the absolute value operation, so as to realize the subtraction of the two signals, And output the subtracted signal as the second waveform signal. It can be understood that the operation process of taking the absolute value of the first waveform signal can also be sent to the second voltage sampling module 20, and what the current compensation circuit 34 receives is the first output of the second voltage sampling module 20 after taking the absolute value. waveform signal.

The current compensation circuit 34 can realize the setting of the preset time by controlling the time for acquiring both the current sampling signal and the first waveform signal. The preset time in this embodiment is selected as the first half-wave cycle or the second half-wave cycle, because in practical applications, the purpose of the current compensation circuit 34 is to always output the second waveform signal representing the standard alternating current, and in the first half-wave cycle After acquiring the second waveform signal of the first half-wave period or the second half-wave period for the second time, the subsequent signal waveform can be obtained by directly copying the first waveform signal. It can be understood that the selection condition of the preset time only needs to satisfy the infinite seamless connection. For example, it can also be selected as the second half period of the first half-wave period and the first half period of the second half-wave period. In this way, the second waveform signal of the subsequent time can be obtained by copying the second waveform signal obtained in the first preset time, which can avoid the sampling inaccuracy caused by the fluctuation of the alternating current in the subsequent time, and can also reduce the power The overall workload of the control device of the factor compensation circuit.

1 to 3 , in an embodiment of the present invention, the first voltage sampling module 10 includes:

The first voltage sensor 11 is used to detect the voltage of the first end of the inductive coil 50 and output a second voltage sampling signal;

The second voltage sensor 12 is used for detecting the voltage at the second end of the inductive coil 50 and outputting a third voltage sampling signal; and

The calculation circuit 13 is configured to perform a subtraction calculation on the second voltage sampling signal and the third voltage sampling signal, and output a first voltage sampling signal according to the calculation result.

In this embodiment, the first voltage sensor 11 and the second voltage sensor 12 are respectively used to obtain the voltage across the inductor coil 50 , of course, in other optional embodiments, the second voltage sensor 12 can also be used to detect the inductor coil 50 The voltage of the first terminal, the first voltage sensor 11 detects the voltage of the second terminal. The calculation circuit 13 may be provided with a subtractor for directly subtracting the third voltage sampling signal and the second voltage sampling signal, and using the waveform obtained after the subtraction as the first voltage sampling signal representing the voltage across the inductor coil 50 output.

1 to 3 , in an embodiment of the present invention, the first waveform signal is a sine wave signal, and the switch driving signal is a PWM control signal.

In this embodiment, the first waveform signal is a sine wave signal having the same phase and frequency as the input alternating current, and the sine wave signal can be represented as a standard form of the alternating current. The PWM control signal can be composed of several high levels and low levels; among them, the switch circuit 60 can be turned on by a high level, and the switch circuit 60 can be turned off by a low level, or it can be triggered by a low level, and the high voltage can be turned on. The flat trigger cut-off is not limited here. And it can be understood that the time occupied by the high level in one cycle is controlled by the first duty cycle signal/the second duty cycle signal. By setting the sine wave signal as the first waveform signal, the standard alternating current can be perfectly represented, and the frequency and phase of the alternating current can be perfectly carried; and by setting the PWM control signal as the switch driving signal, the control of the power factor compensation circuit of the present invention can be achieved. The device realizes the control of the switching frequency of the switching circuit 60 through the first duty cycle signal or the second duty cycle signal.

The present invention also provides a control method of a power factor compensation circuit, which can be based on the above-mentioned control device of the power factor compensation circuit, and can also be applied to the power factor compensation circuit.

4, in an embodiment of the present invention, the control method of the power factor compensation circuit includes the following steps:

Step S100, performing voltage sampling on the inductor coil 50 in the power factor compensation circuit to obtain a first voltage sampling signal;

In this embodiment, the control device of the power factor compensation circuit can sample the voltage of the inductor coil 50 through the first voltage sampling module 10 provided in itself, so as to obtain the real-time voltage value of the inductor coil 50, and output the real-time voltage value representing the real-time voltage value. the first voltage sampling signal. For example, the control device of the power factor compensation circuit can only sample the voltage at the input end of the inductor coil 50 to obtain its voltage value, and then calculate the voltage value and the pre-measured attenuation ratio of the voltage on the inductor coil 50 and the length of the inductance coil 50 measured in advance to calculate, the overall attenuation of the voltage on the inductance coil 50 (the voltage value divided by the inductance coil 50) can be calculated, that is, the voltage of the inductance coil 50, and can output the representative The first voltage sampling signal of the calculation result.

Step S200, performing voltage sampling on the alternating current connected to the power factor compensation circuit to obtain a first waveform signal having the same frequency and the same phase as the alternating current; and

In this embodiment, the control device of the power factor compensation circuit can use the second voltage sampling module 20 to sample the voltage of the alternating current connected to the power factor compensation circuit; the second voltage sampling module 20 can obtain the frequency of the alternating current according to the sampling result information and phase information, and can also output a first waveform signal with the same frequency and the same phase according to the acquired frequency information and phase information, so as to represent the alternating current in a standard state.

Step S300 , output a switch driving signal to the switch circuit 60 according to the first voltage sampling signal and the first waveform signal, so as to control the switching frequency of the switch circuit 60 .

In this embodiment, the control device of the power factor compensation circuit can be used to obtain the voltage of the inductor coil 50 represented by the first voltage sampling signal and the standard alternating current represented by the first waveform signal through the switch driving signal generating module 30 respectively; The signal generation module 30 can also calculate and obtain the corresponding parameters for generating the switch control signal according to the integrated software program or algorithm according to the above two, and then generate the corresponding switch drive signal according to the relevant parameters, and output it to the switch circuit 60, The switching frequency of the switching circuit 60 is controlled, so that the DC power rectified by the rectifying circuit 70 can still output a corresponding DC voltage to the output end of the power factor compensation circuit after being adjusted by the switching circuit 60 and consumed by the inductance coil 50 . The control method of the power factor compensation circuit of the present invention controls the switching frequency of the switching circuit 60 by obtaining the voltage of the inductance coil 50 and the first waveform signal having the same frequency and the same phase as the alternating current, and outputting the switching driving signal in real time, so that it is not necessary to set the switching frequency in advance. The working mode of the power factor compensation circuit is also beneficial to improve the compensation accuracy of the power factor compensation circuit.

Referring to FIG. 5 , in an embodiment of the present invention, the switching driving signal is output to the switching circuit 60 according to the first voltage sampling signal and the first waveform signal, so as to control the switching frequency of the switching circuit 60 The step S300 includes:

Step S310, determining the voltage value corresponding to the first voltage sampling signal and the voltage amplitude value of the first waveform signal;

计算获取第一占空比参数，并根据第一占空比参数生成第一占空比信号；D1为第一占空比参数，L为预设电感值，fsw为预设开关频率，I_Lon1为第一波形信号的电压幅值，Vi-V0为第一电压采样信号对应的电压值；以及Step S320, according to the preset inductance value, the preset switching frequency, the voltage value corresponding to the first voltage sampling signal, the voltage amplitude of the first waveform signal, and the first preset formula:

Calculate and obtain the first duty cycle parameter, and generate the first duty cycle signal according to the first duty cycle parameter; D1 is the first duty cycle parameter, L is the preset inductance value, fsw is the preset switching frequency, I _Lon1 is the voltage amplitude of the first waveform signal, and Vi-V0 is the voltage value corresponding to the first voltage sampling signal; and

Step S330 , generating a switch driving signal according to the preset pulse amplitude and the first duty cycle signal, and outputting it to the switch circuit 60 in the power factor compensation circuit to control the switching frequency of the switch circuit 60 .

In this embodiment, the first duty cycle calculation module 31 in the switch driving signal generation module 30 can run the ADC conversion circuit, the software program for analysis, and the algorithm to determine the voltage value corresponding to the first voltage sampling signal and the voltage amplitude value of the first waveform signal in real time, and can call the pre-stored preset inductance value, preset switching frequency and operation according to the first preset formula after determination. The calculation algorithm is to substitute the preset inductance value, the preset switching frequency, the voltage value corresponding to the first voltage sampling signal and the voltage amplitude value of the first waveform signal into the first preset formula for calculation, so as to obtain the first Duty cycle parameter; the first duty cycle calculation module 31 is further configured to output a first duty cycle signal representing the first duty cycle parameter to the first switch drive signal output module 32 . The first switch drive signal output module 32 is used to obtain the first duty cycle parameter represented by the first duty cycle signal and call the pre-stored preset pulse amplitude when receiving the first duty cycle signal, and generate and output the above two Switch drive signals with corresponding amplitudes and corresponding duty cycles. A real-time first duty cycle parameter can be generated by using the first voltage sampling signal, the first waveform signal and a variety of preset parameter data, and the first duty cycle parameter can be further used to output a corresponding real-time switch driving signal, In order to realize the real-time control of the switch circuit 60 .

Referring to FIG. 6 , in an embodiment of the present invention, the switching driving signal is output to the switching circuit 60 according to the first voltage sampling signal and the first waveform signal, so as to control the switching frequency of the switching circuit 60 The step S300 includes:

Step S340, performing current sampling on the alternating current connected to the power factor compensation circuit to obtain a current sampling signal;

Step S350, obtaining a second waveform signal according to the first waveform signal and the current sampling signal;

Step S360, determining the voltage value corresponding to the first voltage sampling signal and the voltage amplitude value of the second waveform signal;

计算获取第二占空比参数，并根据第二占空比参数生成第二占空比信号；D2为第二占空比参数，L为预设电感值，fsw为预设开关频率，I_lon2为第二波形信号的电压幅值，Vi-V0为第一电压采样信号对应的电压值；Step S370, according to the preset inductance value, the preset switching frequency, the voltage value corresponding to the first voltage sampling signal, the voltage amplitude of the second waveform signal, and the second preset formula:

Calculate and obtain the second duty cycle parameter, and generate the second duty cycle signal according to the second duty cycle parameter; D2 is the second duty cycle parameter, L is the preset inductance value, fsw is the preset switching frequency, I _lon2 is the voltage amplitude of the second waveform signal, and Vi-V0 is the voltage value corresponding to the first voltage sampling signal;

Step S380 , generating a switch driving signal according to the preset pulse amplitude and the second duty cycle signal, and outputting it to the switch circuit 60 in the power factor compensation circuit to control the switching frequency of the switch circuit 60 .

In this embodiment, the control device of the power factor compensation circuit can use the first current sensor 33 to sample the alternating current connected to the power factor compensation circuit, and output a corresponding current sampling signal to the current compensation circuit 34 according to the sampling result. The current compensation circuit 34 is configured to determine corresponding parameters of the standard AC current according to the first voltage sampling signal and the current sampling signal, and generate a second waveform signal representing the standard AC current according to the corresponding parameters and output it to the second duty cycle calculation module 35 .

The second duty cycle calculation module 35 in the switch drive signal generation module 30 can determine in real time by running corresponding hardware circuits and software programs and algorithms for analysis when receiving the first voltage sampling signal and the second waveform signal. The voltage value corresponding to the first voltage sampling signal and the voltage amplitude value of the second waveform signal can also be determined, and the pre-stored preset inductance value, preset switching frequency and the algorithm calculated according to the second preset formula can also be called after determination. , the preset inductance value, the preset switching frequency, the voltage value corresponding to the first voltage sampling signal and the voltage amplitude of the second waveform signal are all substituted into the second preset formula for calculation, so as to obtain the second duty cycle parameter ; The second duty cycle calculation module 35 is further configured to output the second duty cycle signal representing the second duty cycle parameter to the second switch drive signal output module 36 . The second switch driving signal output module 36 is configured to, when receiving the second duty cycle signal, obtain the second duty cycle parameter represented by it, call the pre-stored preset pulse amplitude, and generate and output the above two Switch drive signals with corresponding amplitudes and corresponding duty cycles. In this way, the real-time second waveform signal can be obtained first through the first waveform signal and the current sampling signal, and then the real-time second waveform signal can be generated according to the real-time second waveform signal, the first voltage sampling signal and various preset parameter data. Two duty cycle parameters, and can further use the second duty cycle parameter to output a corresponding real-time switch driving signal, so as to realize real-time control of the switch circuit 60 .

Referring to FIG. 7 , in an embodiment of the present invention, the step S350 of acquiring a second waveform signal according to the first waveform signal and the current sampling signal is specifically:

Obtain the absolute value of the average value of the amplitude of the current sampling signal within the preset time and the absolute value of the amplitude of the first waveform signal within the preset time, and set the first waveform signal at the preset time The absolute value of the inner amplitude and the absolute value of the average value are subtracted, and a second waveform signal is generated according to the calculation result; wherein, each cycle of the alternating current connected to the power factor compensation circuit is divided into a first half-wave period and the second half-wave period, and the preset time is the first half-wave period or the second half-wave period.

In this embodiment, the current compensation circuit 34 can use a hardware circuit provided therein, such as a filter circuit, to achieve the average value of all amplitudes of the first waveform signal received within a preset time; After the average, the algorithm for taking the absolute value is run to perform the absolute value operation on the average value to obtain the absolute value of the average value. At the same time, the current compensation circuit 34 can also access the first waveform signal synchronously to obtain its real-time amplitude, and the absolute value of the real-time amplitude and the above average value can be obtained through a subtractor or an algorithm for subtraction calculation. The current compensation circuit 34 can output the corresponding second waveform signal according to the real-time result. . For the selection of the preset time, reference may be made to the foregoing embodiments, as long as the connection can be infinitely seamless, which is not repeated here. By using the first waveform signal and the current sampling signal, the second waveform signal representing the standard alternating current can also be obtained to control the switch circuit 60 in real time, and the second waveform obtained in the first preset time can also be copied. The waveform signal is used to repeatedly obtain the second waveform signal in the subsequent time, which is beneficial to avoid sampling inaccuracy caused by AC fluctuation in the subsequent time, and can also reduce the overall workload of the control device of the power factor compensation circuit.

Referring to FIG. 8 , in an embodiment of the present invention, the step S100 of sampling the voltage of the inductor coil 50 in the power factor compensation circuit to obtain the first voltage sampling signal includes:

Step S110, performing voltage detection on the voltage at the first end of the inductor coil 50 to obtain a second voltage sampling signal;

Step S120, performing voltage detection on the voltage at the second end of the inductor coil 50 to obtain a third voltage sampling signal;

Step S130: Perform a subtraction calculation on the second voltage sampling signal and the third voltage sampling signal, and generate a first voltage sampling signal according to the calculation result.

In this embodiment, the first voltage sampling module 10 can detect the voltage of the first end and the second end of the inductance coil 50 respectively through two voltage sensors provided separately in the first voltage sampling module 10, and can obtain the characteristics of the inductance coil 50 respectively. The second voltage sampling signal representing the voltage at the first end and the third voltage sampling signal representing the voltage at the second end; in this embodiment, the first end of the inductor coil 50 is used as the input end, and the second end is the output An example is used for explanation. It can be understood that the voltage of the first end of the inductor coil 50 is its input voltage, and the voltage of its second end is its output voltage, and its input voltage must be greater than its output voltage, so the first voltage sampling module 10 Both the second voltage sampling signal and the third voltage sampling signal are sent to the calculation circuit 13 therein to perform subtraction calculation between the two. The calculation result of the subtraction calculation is the first voltage sampling signal representing the voltage of the inductor coil 50 . The technical solution of the present invention outputs the first voltage sampling signal according to the difference between the second voltage sampling signal and the third voltage sampling signal, compared to directly measuring the coil voltage of the inductor coil 50 to output the first voltage sampling signal , which can avoid the influence of the temperature difference caused by the passage of large current on its measurement results.

The invention also provides a power factor compensation circuit.

9, in an embodiment of the present invention, the power factor compensation circuit includes:

DC output 40;

The inductor coil 50 is used for connecting with the AC input terminal through the rectifier circuit 70, so as to output the DC power output after rectification by the rectifier circuit 70 to the DC output terminal 40;

a switch circuit 60 for controlling the direct current output from the rectifier circuit 70 to the inductor coil 50 according to the switch drive signal; and

The control device of the power factor compensation circuit as described above, the control device of the power factor compensation circuit is respectively connected with the AC input end, the inductance coil 50 and the switch circuit 60; A control method of a power factor compensation circuit.

In this embodiment, the first end of the inductance coil 50 can be connected to the AC input end via a rectifier circuit 70 constructed of diodes, so as to receive the DC power rectified and output by the rectifier circuit 70 and output to the DC output from the second end thereof end 40. And it can be understood that the second end of the inductance coil 50 can be connected to the output end of the power factor compensation circuit; the power factor compensation circuit can also be provided with a filter capacitor C, and one end of the filter capacitor C can be connected to the second end of the inductance coil 50. The other end can be connected to the ground, so as to filter the output DC power of the inductor coil 50 and output it to the output end of the power factor compensation circuit.

The switch circuit 60 may be one or more combinations of switch devices such as MOS transistors, triodes, and thyristors. The input end of the switch circuit 60 can be connected to the common end of the rectifier circuit 70 and the inductance coil 50, its output end can be grounded, and its controlled end can be connected to the control end of the control device of the power factor compensation circuit, that is, to the control device in the control device. The output end of the switch driving signal generating module 30 is connected to be turned on/off under the control of the output switch driving signal. In an optional embodiment, the switch circuit 60 is constructed by using two MOS transistors S1 and S2 connected in parallel.

Since the power factor compensation circuit includes the control device of the power factor compensation circuit; the detailed structure of the control device of the power factor compensation circuit can refer to the above-mentioned embodiments, and will not be repeated here; The control device of the power factor compensation circuit is used in the above-mentioned power factor compensation circuit. Therefore, the embodiment of the power factor compensation circuit includes all the technical solutions of all the embodiments of the control device of the power factor compensation circuit, and the technical effects achieved are also the same. This will not be repeated here. The power factor compensation circuit can also use the above-mentioned control method of the power factor compensation circuit. The control method of the power factor compensation circuit has been described above, and will not be repeated here.

The present invention also provides an electrical device, which includes the power factor compensation circuit as described above. The detailed structure of the power factor compensation circuit can refer to the above-mentioned embodiments, and details are not repeated here; All the technical solutions of all the embodiments of the factor compensation circuit, and the technical effects achieved are also the same, and will not be repeated here.

In this embodiment, in addition to the power factor compensation circuit, the electrical equipment may also include a circuit load. The input end of the power factor compensation circuit can be connected with the power supply end of the electrical equipment, and the output end of the power factor compensation circuit can be connected with the circuit load.

The above descriptions are only optional embodiments of the present invention, and are not intended to limit the scope of the present invention. Under the inventive concept of the present invention, any equivalent structural transformations made by using the contents of the description and drawings of the present invention, or direct/indirect Applications in other related technical fields are included in the scope of patent protection of the present invention.

Claims (14)

1. A control device for a power factor compensation circuit, characterized in that the power factor compensation circuit comprises an inductance coil for accessing alternating current through a rectifier circuit and a switch for controlling the direct current output from the rectifier circuit to the inductance coil according to a switch drive signal circuit, the control device of the power factor compensation circuit includes: a first voltage sampling module, configured to perform voltage sampling on the voltage of the inductor coil in the power factor compensation circuit, and output a first voltage sampling signal; a second voltage sampling module, configured to perform voltage sampling on the alternating current connected to the power factor compensation circuit, and output a first waveform signal having the same frequency and the same phase as the alternating current; and A switch drive signal generation module, configured to generate a switch drive signal according to the first voltage sampling signal and the first waveform signal, and output it to the controlled end of the switch circuit in the power factor compensation circuit to control the switch the switching frequency of the circuit. 2. The control device of the power factor compensation circuit according to claim 1, wherein the switch driving signal generating module comprises: The first duty cycle calculation module is used to obtain a preset inductance value, a preset switching frequency, a voltage value corresponding to the first voltage sampling signal, and a voltage amplitude of the first waveform signal, and is used to calculate the The preset inductance value, the preset switching frequency and the voltage amplitude of the first waveform signal are multiplied and calculated, and then the voltage value corresponding to the first voltage sampling signal is divided and calculated, and the first voltage value is output according to the calculation result. duty cycle signal; and The first switch drive signal output module is configured to output the switch drive signal according to the preset pulse amplitude and the received first duty cycle signal. 3. The control device of the power factor compensation circuit according to claim 1, wherein the switch driving signal generating module comprises: a first current sensor, used for sampling the alternating current connected to the power factor compensation circuit, and outputting a current sampling signal; a current compensation circuit, configured to output a second waveform signal according to the first waveform signal and the current sampling signal; The second duty cycle calculation module is used to obtain the preset inductance value, the preset switching frequency, the voltage value corresponding to the first voltage sampling signal and the voltage amplitude of the second waveform signal, and is used to calculate the The preset inductance value, the preset switching frequency and the voltage amplitude of the second waveform signal are multiplied and calculated, and then the voltage value corresponding to the first voltage sampling signal is divided and calculated, and a second voltage value is output according to the calculation result. duty cycle signal; and The second switch driving signal output module is configured to output the switch driving signal according to the preset pulse amplitude and the received second duty cycle signal. 4 . The control device of the power factor compensation circuit according to claim 3 , wherein the current compensation circuit is used to obtain the absolute value of the average value of the amplitude of the current sampling signal within a preset time and the The absolute value of the amplitude of the first waveform signal within the preset time is calculated by subtracting the absolute value of the amplitude of the first waveform signal within the preset time and the absolute value of the average value, and according to The calculation result outputs a second waveform signal to the second duty cycle calculation module. 5. The control device of the power factor compensation circuit according to claim 4, wherein each cycle of the alternating current connected to the power factor compensation circuit is divided into a first half-wave cycle and a second half-wave cycle, so The preset time is the first half-wave period or the second half-wave period; The current compensation circuit is configured to obtain the absolute value of the average value of the amplitude of the current sampling signal in the first half-wave cycle or the second half-wave cycle. 6. The control device of a power factor compensation circuit according to claim 1, wherein the first voltage sampling module comprises: a first voltage sensor for detecting the voltage at the first end of the inductance coil and outputting a second voltage sampling signal; a second voltage sensor for detecting the voltage at the second end of the inductive coil and outputting a third voltage sampling signal; and The calculation circuit is configured to perform a subtraction calculation on the second voltage sampling signal and the third voltage sampling signal, and output a first voltage sampling signal according to the calculation result. 7 . The control device of a power factor compensation circuit according to claim 1 , wherein the first waveform signal is a sine wave signal, and the switch driving signal is a PWM control signal. 8 . 8. A control method for a power factor compensation circuit, characterized in that the power factor compensation circuit comprises an inductance coil for connecting alternating current through a rectifier circuit and a switch for controlling the direct current output from the rectifier circuit to the inductance coil according to a switch drive signal Circuit, the control method of the power factor compensation circuit includes the following steps: performing voltage sampling on the inductor coil in the power factor compensation circuit to obtain a first voltage sampling signal; performing voltage sampling on the alternating current connected to the power factor compensation circuit to obtain a first waveform signal having the same frequency and the same phase as the alternating current; and A switch driving signal is output to the switch circuit according to the first voltage sampling signal and the first waveform signal, so as to control the switching frequency of the switch circuit. 9 . The control method of a power factor compensation circuit according to claim 8 , wherein the output switch driving signal to the switch circuit according to the first voltage sampling signal and the first waveform signal to control the power factor compensation circuit. 10 . The steps of switching the switching frequency of the switching circuit include: determining a voltage value corresponding to the first voltage sampling signal and a voltage amplitude value of the first waveform signal; According to the preset inductance value, the preset switching frequency, the voltage value corresponding to the first voltage sampling signal, the voltage amplitude of the first waveform signal, and the first preset formula:

Calculate and obtain the first duty cycle parameter, and generate the first duty cycle signal according to the first duty cycle parameter; D1 is the first duty cycle parameter, L is the preset inductance value, fsw is the preset switching frequency, I _Lon1 is the voltage amplitude of the first waveform signal, and Vi-V0 is the voltage value corresponding to the first voltage sampling signal; and The switch driving signal is generated according to the preset pulse amplitude and the first duty cycle signal, and output to the switch circuit in the power factor compensation circuit to control the switching frequency of the switch circuit. 10 . The control method of a power factor compensation circuit according to claim 8 , wherein the outputting a switch driving signal to the switch circuit according to the first voltage sampling signal and the first waveform signal to control the power factor compensation circuit. 11 . The steps of switching the switching frequency of the switching circuit include: Perform current sampling on the alternating current connected to the power factor compensation circuit to obtain the current sampling signal; obtaining a second waveform signal according to the first waveform signal and the current sampling signal; determining a voltage value corresponding to the first voltage sampling signal and a voltage amplitude value of the second waveform signal; According to the preset inductance value, the preset switching frequency, the voltage value corresponding to the first voltage sampling signal, the voltage amplitude of the second waveform signal, and the second preset formula:

Calculate and obtain the second duty cycle parameter, and generate the second duty cycle signal according to the second duty cycle parameter; D2 is the second duty cycle parameter, L is the preset inductance value, fsw is the preset switching frequency, I _Lon2 is the voltage amplitude of the second waveform signal, and Vi-V0 is the voltage value corresponding to the first voltage sampling signal; The switch driving signal is generated according to the preset pulse amplitude and the second duty cycle signal, and is output to the switch circuit in the power factor compensation circuit to control the switching frequency of the switch circuit. 11 . The control method for a power factor compensation circuit according to claim 10 , wherein the acquiring the second waveform signal according to the first waveform signal and the current sampling signal is specifically: 11 . Obtain the absolute value of the average value of the amplitude of the current sampling signal within the preset time and the absolute value of the amplitude of the first waveform signal within the preset time, and set the first waveform signal at the preset time The absolute value of the inner amplitude and the absolute value of the average value are subtracted, and a second waveform signal is generated according to the calculation result; wherein, each cycle of the alternating current connected to the power factor compensation circuit is divided into a first half-wave period and the second half-wave period, and the preset time is the first half-wave period or the second half-wave period. 12. The control method of the power factor compensation circuit according to claim 8, wherein the step of sampling the voltage of the inductor coil in the power factor compensation circuit to obtain the first voltage sampling signal comprises: performing voltage detection on the voltage at the first end of the inductance coil to obtain a second voltage sampling signal; performing voltage detection on the voltage at the second end of the inductance coil to obtain a third voltage sampling signal; The second voltage sampling signal and the third voltage sampling signal are subtracted, and a first voltage sampling signal is generated according to the calculation result. 13. A power factor compensation circuit, wherein the power factor compensation circuit comprises: DC output; The inductance coil is used for connecting with the AC input terminal through the rectifier circuit, so as to output the DC power output after rectification by the rectifier circuit to the DC output terminal; a switch circuit for controlling the direct current output from the rectifier circuit to the inductor coil according to the switch drive signal; and The control device for a power factor compensation circuit according to any one of claims 1 to 7, wherein the control device for the power factor compensation circuit is respectively connected to the AC input terminal, the inductance coil and the switch circuit; or, The control method of the power factor compensation circuit according to any one of claims 8-12 is used. 14. An electrical device, characterized in that, the electrical device comprises the power factor compensation circuit of claim 13.

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