CN1383042A - Automatic controller for lowering pressure of high-pressure gas by volume expansion - Google Patents

Abstract

The invention discloses an automatic control device for volume expansion and decompression of high-pressure gas. It is an ultra-high pressure pneumatic decompression system integrating high pressure pneumatic control valve, sensor, controller and volume expansion vessel. By collecting the pressure data of the low-pressure volume expansion vessel in real time, according to certain control requirements and control algorithms, the controller issues instructions to control the switching time of the high-pressure pneumatic switching valve, so as to realize the automatic control of the volume decompression process of high-pressure or ultra-high-pressure gas . By controlling the decompression of high-pressure or ultra-high-pressure gas, compared with throttling and decompression, energy can be saved by 10-35% during the decompression process. The device of the present invention is simple in composition, can be conveniently installed or connected into the energy control link of the high-pressure gas power system, and realizes automatic control of volume expansion and decompression of the high-pressure gas, thereby achieving the purpose of efficiently utilizing the energy of the high-pressure gas power system. It can be used in fields such as energy control systems powered by compressed air, especially in energy control systems of pneumatic vehicles powered by compressed air.

Description

High-pressure gas volume expansion and decompression automatic control device

Technical field

The invention relates to a high-pressure gas volume expansion and decompression control method and an automatic control device.

Background technique

In the field of background technology, the functions closest to the present invention are throttling pressure regulating devices, that is, various gas pressure reducing valves. Although the pressure reducing valve technology is relatively mature at present and can meet the application of pneumatic systems that work intermittently and only have functional requirements, it realizes pressure regulation through throttling control. The throttling control is an irreversible energy change process. For the aerodynamic power system with continuous operation and high dynamic performance requirements, there is a large energy loss, which is not conducive to the efficient utilization of the system.

The element used for volumetric expansion and decompression is the expansion vessel. Its working principle is to adjust the output pressure of the high-pressure pneumatic system through the pneumatic switch valve and the expansion vessel. The principle of volume expansion and decompression works according to the state equation of gas. Under certain conditions, the pressure of a certain amount of gas is inversely proportional to its filled volume, that is, the volume increases and the pressure decreases. The function of the expansion vessel is to reduce the upstream high-pressure gas to the low-pressure gas required by the work by increasing the volume. If it expands under isotropic and isentropic conditions, it is a reversible process with essentially no loss of energy. Through the PLC control method and PID regulation control switch valve, the expander can accurately control the output pressure of the conventional pneumatic system, the control method is flexible, and the control accuracy can be within 1.0kPa. In contrast, in a conventional pneumatic system, 5-10% of the energy of the system will be lost by throttling to adjust the pressure to overcome frictional resistance; in a high-pressure pneumatic system, the energy loss caused by throttling will be even greater. Volume expansion and decompression control is also different from throttling and decompression in terms of process and state. There is no throttling loss in the process of volume expansion and decompression; the decompressed low-pressure gas can be stored in a low-pressure gas storage tank for a period of time to be heated with the outside world. compensate. In this process, as long as the external energy is high enough and there is enough time to replenish the energy of the system, the lost energy can be partially replenished and recovered, thus ensuring the efficient utilization of system energy. Theoretical analysis has proved that the volume decompression control mode can reduce the energy loss by 10-35% compared with the throttling decompression control mode to reduce the ultra-high pressure gas with a pressure of 30 MPa to a pressure of 1.0-5.0 MPa.

Contents of invention

The purpose of the present invention is to provide an automatic control device for volume expansion and decompression of high-pressure gas integrating high-pressure pneumatic control valve, pressure sensor, flow sensor, controller and volume expansion container, so as to realize automatic control of volume expansion and decompression of high-pressure gas .

The technical scheme that the present invention adopts is as follows:

It includes air source pressure sensor and display instrument, high pressure globe valve, high pressure pneumatic switch valve, controller, volume expansion vessel, decompression pressure sensor and display instrument, decompression temperature sensor and display instrument, low pressure globe valve; high pressure pneumatic switch valve The air inlet of the air inlet is connected with the high-pressure stop valve through the high-pressure pipeline and the joint, the air outlet is connected with the air inlet of the volume expansion vessel through the high-pressure pipeline and the joint, and the control terminal wiring is connected with the output port of the controller; the air outlet of the volume expansion vessel is connected through The joint is connected to one end of the low-pressure shut-off valve, and the other end of the low-pressure shut-off valve is connected to the low-pressure pipeline and the joint; the decompression pressure sensor and display instrument and the decompression and temperature sensor and display instrument are all installed on the volume expansion vessel, and their signal output The leads are connected to the input port of the controller.

The controller is equipped with data acquisition, data processing and control output modules; the output leads of the air source pressure sensor and display instrument, decompression pressure sensor and display instrument, decompression temperature sensor and display instrument are respectively connected to the respective sampling/holding circuit and After entering the data acquisition module composed of A/D conversion circuit, entering the data processing module composed of CPU, program and data memory, and entering the control output module composed of power amplifier circuit, it is connected to the control end of the high-pressure pneumatic switch valve.

The pressure sensor and the temperature sensor respectively provide the pressure and temperature data of the high-pressure gas source and the volume expansion and decompression state; the controller is equipped with functional modules such as data acquisition, data processing and control output, which can collect the required pressure and temperature data in real time, and According to the set control requirements and control algorithm, the switching time of the high-pressure pneumatic switching valve is controlled; the volume expansion container ensures that the entering high-pressure gas realizes the volume expansion and decompression process; the parameter value of the decompression state can be collected and calculated by the controller in real time, Therefore, the automatic control of the volume decompression process of the high-pressure gas is realized.

The invention has the advantages of simple composition, automatic control function, no throttling loss in the process of volume expansion and decompression control of high-pressure gas, compared with throttling and decompression, it can save energy by 10-35 during the decompression process. %, high energy utilization. The invention integrates machinery, electronics and fluid control, and is a typical automatic control system of electromechanical integration. The present invention can be easily installed or connected into the energy control link of the high-pressure gas power system to realize the automatic control of the volume expansion and decompression of the high-pressure gas, so as to achieve the purpose of efficiently utilizing the energy of the high-pressure gas power system. It can be applied to compressed air Powered energy control system and other fields, especially in the energy control system of pneumatic vehicles powered by compressed air.

Description of drawings

Fig. 1 is a schematic diagram of the structure principle of the present invention;

Fig. 2 is a block diagram of the principle of the controller of the present invention.

Detailed ways

As shown in Figure 1, the described high-pressure gas volume decompression device consists of a high-pressure pneumatic switch valve 4, a controller 5, a volume expansion vessel 6, a high-pressure cut-off valve 2, pressure sensors and display instruments 1 and 7, a temperature sensor and display instruments 8. Low-pressure cut-off valve 9, high-pressure pipeline and joint 3, low-pressure pipeline and joint 10, etc.

The air inlet of the high-pressure pneumatic switching valve 4 is connected to the high-pressure stop valve 2 through a joint and a high-pressure pipeline, the air outlet is connected to the air inlet of the volume expansion vessel 6 through a joint and a high-pressure pipeline, and the control terminal wiring is connected to the output port of the controller 5 . The high-pressure pneumatic switch valve 4 is controlled by the control signal sent by the controller 5, and is used to control the cycle and time of the high-pressure gas entering the expansion vessel 6, and make the gas pass through the high-pressure pneumatic switch valve 4 to generate a small pressure drop and irreversible energy The loss is small, which is conducive to energy saving.

The air inlet of the volume expansion vessel 6 is connected with the gas outlet of the high-pressure pneumatic switching valve 4 through a joint and a high-pressure pipeline, and the gas outlet is connected with the low-pressure cut-off valve 9 through a joint. The volume expansion vessel 6 is a gas tank that can withstand high pressure and has a set volume. Its function is to make the incoming high-pressure gas expand in the tank according to the adiabatic process or variable process, so as to reduce the gas pressure and realize decompression, thereby eliminating Irreversible energy loss during throttling and decompression.

The pressure sensor and display instrument 7 are installed on the volume expansion vessel 6, and its signal output leads are connected with the input port of the controller 5. The pressure sensor and display instrument 7 display the gas pressure value of the volume expansion vessel and transmit it to the controller, which is convenient for monitoring and provides information and data for the controller to control the on-off valve.

The pressure sensor and display instrument 1 are installed at the outlet of the high-pressure gas source, that is, the inlet of the high-pressure gas volume decompression device, and its signal output leads are connected with the input port of the controller 5 . The pressure sensor and display instrument 1 displays the gas pressure value of the high-pressure gas source and transmits it to the controller, which is convenient for monitoring and provides information and data for the controller to realize the control of the on-off valve.

The temperature sensor and display instrument 8 are installed on the volume expansion vessel 6 , and its signal output leads are connected with the input port of the controller 5 . The temperature sensor and display instrument 8 display the gas temperature value of the volume expansion vessel and transmit it to the controller, which is convenient for monitoring and provides information and data for the controller to realize the control of the on-off valve

As shown in Figure 2, the controller 5 is provided with functional modules such as data collection, data processing and control output. The data acquisition module is composed of a sample and hold circuit and an A/D conversion circuit, and is used to collect working parameter values such as the pressure of the high-pressure gas source, the pressure and temperature of the volume expansion and decompression gas; the data processing module includes a CPU program and a data memory, which can be used according to Control requirements and algorithms process the sampled data and send them to the input of the amplifier circuit for control output; the control output module is mainly a power amplifier circuit that drives the on-off valve to control the opening and closing time and cycle of the high-pressure pneumatic on-off valve. In order to realize the control of the volume decompression system.

The high-pressure cut-off valve 2 is used to ensure the static sealing and safety of the high-pressure gas volume decompression device; the low-pressure cut-off valve 9 is used to adjust the gas output of the gas-consuming components or systems.

The high-pressure gas volume decompression device is generally installed between the high-pressure gas source and the pneumatic motor (pneumatic actuator). When working, first open the high-pressure cut-off valve 2 to the maximum opening state, so that the high-pressure gas can reach the air inlet of the high-pressure pneumatic switch valve 4 without hindrance, and then the high-pressure pneumatic switch can be controlled by the controller 5 according to the decompression control requirements of the system. The valve 4 controls the opening and closing state, thereby controlling the decompression process and decompression index of the high-pressure gas in the volume expansion vessel, so as to meet the power demand of the air-driven engine.

Claims (2)

1. The automatic control device for volume expansion and decompression of high-pressure gas is characterized in that it includes a gas source pressure sensor and a display instrument (1), a high-pressure cut-off valve (2), a high-pressure pneumatic switch valve (4), a controller (5), Volume expansion vessel (6), decompression pressure sensor and display instrument (7), decompression temperature sensor and display instrument (8), low-pressure cut-off valve (9); the air inlet of high-pressure pneumatic switch valve (4) passes through the high-pressure pipeline The joint (3) is connected with the high-pressure cut-off valve (2), the air outlet is connected with the air inlet of the volume expansion vessel (6) through the high-pressure pipeline and the joint, and the control terminal wiring is connected with the output port of the controller (5); the volume expansion The gas outlet of the container (6) is connected to one end of the low-pressure shut-off valve (9) through a joint, and the other end of the low-pressure shut-off valve (9) is connected to the low-pressure pipeline and the joint (10); the decompression pressure sensor and display instrument (7) and Decompression and temperature sensors and display instruments (8) are all installed on the volume expansion vessel (6), and their signal output leads are connected with the input port of the controller (5). 2. The automatic control device for volume expansion and decompression of high-pressure gas according to claim 1, characterized in that: said controller (5) is provided with data acquisition, data processing and control output modules; gas source pressure sensor and display instrument (1), decompression pressure sensor and display instrument (7), decompression temperature sensor and display instrument (8) output leads are respectively connected to respective data acquisition modules composed of sample/hold circuits and A/D conversion circuits, enter The data processing module composed of CPU, program and data memory enters the control output module composed of power amplifier circuit, and is connected to the control end of the high-pressure pneumatic switch valve (4).