SU922450A1 - Method of regulating helium system - Google Patents

Description

I

The invention relates to the automatic regulation of technological. cryogenic systems and can be used in cryogenic helium systems. A method of controlling a helium system, including a cryogenic unit with a pre-cooling expander stage, is known by controlling the costs of the cryoagent supplied to the cooling object and bypassed through the expander stage according to the temperature at the outlet of object 1.

The disadvantage of this method is the high energy consumption for cold, due to the fact that the disturbing factors are not controlled and not taken into account during operation.

The purpose of the invention is to reduce energy. cost of getting cold.

The goal is achieved by additionally measuring the temperature of the direct flow cryoagent after the expander stage and correcting the costs of the cryoagent supplied to the object and transferred through the expander stage, and when the temperature of the cryoagent at the outlet of the object changes, the cryoagent pressure is controlled depending on it object.

The drawing shows schematically the system implementing this method.

The system contains a compressor 1, a controlled expander 2, a pre-cooling stage 3, a temperature sensor 4 on the forward flow

IS after expander heat exchanger,. temperature sensor 5 at the outlet of the cooling object, pressure sensor 6 at the outlet of the object, forward flow line 7, expansion device 8 on the forward flow, cooling object 9, expansion device 10 on the return flow, return flow line 11, regenerative 9 heat exchangers 12–15 between the forward and reverse flows, pressure sensor 1b on the forward flow after compressor 1, gas tank 17, controllers 18–20, 2, and adders 21–23. The system operates as follows: 1 Helium is compressed in compressor 1 and sent to direct flow line 7, from where it is directed to cooling facility 9 through direct cooling and heat exchangers 2 through 15 to direct cooling in each heat exchanger by reverse flow. A part of the direct flow is taken to the expander 2 and, after expansion, is returned to the return flow line 11. Another part of the direct flow is directed to the cooling of the object 9, and then to the line. But To stabilize the suction pressure of the compressor 1, the gas tank 17 is used. using a system of sensors, regulators and actuators. When the load changes in the object 9, the temperature sensor 5 records the change in temperature at the exit from the object, which leads to a change in temperature and pressure in all nodes of this system. The temperature measured by sensor f determines the cooling capacity of the expander and the cooling capacity of the whole system and therefore this temperature will unambiguously determine the temperature behind the object 9. When the temperature changes, measured by sensor 5, a signal is output to the controller 19, which controls the actuator of the expansion device 8. At the same time, the signal from the temperature sensor k is fed to the regulator 18, and an additional correction signal to the actuator of the expansion device 8o The throughput of the device 8 depends on the sum of the signals supplied from the regulators 18 and 19, which are summed. In the adder 22, the expander 8 stabilizes the temperature measured by sensor 5 by changing the forward flow in line 7 supplied to the object 9 cooling. With a change in the flow rate of this flow, the pressure j measured by sensor 6 at the outlet of object 9 changes. It is stabilized by a signal from pressure sensor 6 by a regulator 20, which outputs a signal to the actuator of the expansion device 10, Simultaneously from sensor 5 The torus 19 receives a correction signal to the actuator of the device 10 ". The capacity of the device 10 depends on the sum of the signals supplied from the regulators 19 and 20, which are summed in the adder 23. Such compensation In the process of regulation, chi eliminates temperature fluctuations resulting from the accumulation of gases in the communications of the object and the exhaust of gas from the expansion device 10. With a change in temperature measured by sensor 5, the temperature measured by sensor k begins to change. It is regulated by the signal ot of the temperature sensor 4 by the V8 controller, which sends a signal to the device dp of performance control of the expander 2 (not shown), the signal from the temperature sensor S is fed to the controller 19, and an correction signal is received on the device to control the performance of the expander. The pressure after the compressor is stabilized by a signal from pressure sensor 16 by regulator 2, which outputs a signal to the actuator of the compressor 1 regulating device. This control spacing ensures efficient operation of the system with the least amount of energy needed for cold. Claims The method of controlling a helium system, including a cryogenic unit with a pre-cooling expander stage, by controlling the costs of a cryoagent supplied to the cooling object and passed through the expander stage, according to the temperature at the exit from the object, in order to reduce energy costs for getting cold , the temperature of the direct flow cryoagent is additionally measured after the expander stage, and the costs of the cryoagent supplied to

the object and bypass through the expander stage, and when the temperature of the cryogenic agent is changed at the exit from the object, the pressure of the cryoagate behind the object is adjusted depending on it.

Sources of information taken into account in the examination

I. USSR author's certificate in application number 27b9b2b, class, F 25 B 9/00, 1979o

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Claims (1)

Claim A method for controlling a helium system, including a cryogenic installation with an expander pre-cooling stage, by controlling the costs of the cryoagent supplied to the cooling object and passed through the expander stage, according to the temperature at the outlet of the object, characterized in that, in order to reduce energy costs for obtaining cold, additionally measure the temperature of the cryoagent of the direct flow behind the expander stage and - adjust the costs of the cryoagent supplied to it VNIIIPI Order 2551/49 Circulation 542 Subscription Branch of the PPP Patent, Uzhgorod, Project 4,