CN109556984B

CN109556984B - Rapid charge pre-cooling system and method of use

Info

Publication number: CN109556984B
Application number: CN201811490776.0A
Authority: CN
Inventors: 郭晓璐; 陈学东; 范志超; 徐鹏; 刘孝亮
Original assignee: Hefei General Machinery Research Institute Special Equipment Inspection Station Co ltd; Hefei General Machinery Research Institute Co Ltd
Current assignee: Hefei General Machinery Research Institute Special Equipment Inspection Station Co ltd; Hefei General Machinery Research Institute Co Ltd
Priority date: 2018-12-07
Filing date: 2018-12-07
Publication date: 2021-08-31
Anticipated expiration: 2038-12-07
Also published as: CN109556984A

Abstract

The invention relates to a rapid inflation pre-cooling system and a method for using the same. The system includes an inflation subsystem and N temperature control subsystems, and the pipelines of the inflation subsystem are provided with heat exchanges corresponding to the N temperature control subsystems one-to-one. The pipeline is also provided with a valve group, a first flow meter, a sensor, and a test gas cylinder is connected to the end of the pipeline; each temperature control subsystem includes a working device that forms a loop with the corresponding heat exchange device, The working control valve and several flowmeters are arranged on the loop, and the system also includes a control subsystem respectively connected with the valve group, the first flowmeter, the sensor, the working device, the working control valve, and the controlled end of the flowmeter. The cooling capacity of the temperature control subsystem corresponding to the multiple heat exchange devices on the pipeline of the gas charging subsystem is gradually enhanced according to the flow direction of the gas. The advantages of the invention lie in that it realizes the staged precooling for fast and accurate adjustment of the gas temperature at the inlet of the test gas cylinder, and the flow rate of the gas is controlled by the valve group on the inflation subsystem.

Description

Rapid inflation precooling system and use method thereof

Technical Field

The invention relates to the field of precooling tests, in particular to a quick inflation precooling system and a use method thereof.

Background

The composite material gas cylinder has the advantages of high pressure bearing capacity and light weight, is more and more widely applied to the existing high-pressure gas storage technology, and becomes the mainstream of research, development and application. Because the composite material gas cylinder has high working pressure and is easily influenced by temperature, the working medium is usually inflammable and explosive, and leakage and explosion accidents are very easy to happen when the gas cylinder is damaged and the safety performance is reduced in the process of quick inflation; therefore, the safety service performance is the research direction of the important concern. Taking hydrogen as an example, in order to meet market demand, a hydrogen storage cylinder needs to rapidly increase the pressure to a rated value within about 3-5 minutes. In the process of quickly charging hydrogen into the gas cylinder, severe temperature change caused by a temperature rise effect generates larger temperature difference stress between layers of the composite material, so that the mechanical property of a resin matrix is influenced, and the fatigue life of the gas cylinder is reduced; the highest temperature rise of the hydrogen can reach more than 130 ℃, and the safety performance of the epoxy resin used by the composite material gas cylinder is influenced when the working temperature of the epoxy resin exceeds 100 ℃; therefore, the temperature rise index of the hydrogen in the gas cylinder in the quick charging process needs to be controlled by a precooling system, and the maximum temperature is limited to be below 85 ℃. The rapid hydrogen filling process in the vehicle-mounted gas cylinder hydrogen circulation fatigue test system is under the complex working conditions of variable temperature and variable flow, and the key step of the hydrogen filling process is how to effectively control the temperature in the gas cylinder under the working conditions.

Because the actual hydrogen storage cylinder quick charging process is influenced by the specific hydrogenation system setting and the structure size of the cylinder, the existing quick charging temperature rise analysis result has poor universality and does not have strong reference value. In the published patent, the fatigue performance test of most of the prior high-pressure hydrogen storage cylinders is carried out on a hydraulic testing machine, and the difference between the obtained test data and the real working condition of a hydrogen medium is larger; in the patent of the gas cylinder testing system based on the real hydrogen medium, a grading precooling system which can realize the rapid and accurate regulation of the temperature of the hydrogen at the inlet of the gas cylinder in the rapid hydrogen charging process aiming at the working conditions of variable temperature and variable flow is lacked. This problem also exists for some similar gases.

Disclosure of Invention

To overcome the above-described deficiencies of the prior art, the present invention provides a rapid air-charge pre-cooling system.

In order to achieve the purpose, the invention adopts the following technical scheme:

the system comprises an inflation subsystem and N temperature control subsystems, wherein heat exchange devices which correspond to the N temperature control subsystems in a one-to-one mode are arranged on a pipeline of the inflation subsystem, a valve bank, a first flowmeter and a sensor are further arranged on the pipeline, and a test gas cylinder is further connected to the tail end of the pipeline; each temperature control subsystem comprises a working device forming a loop with the corresponding heat exchange device, a working control valve and a plurality of flow meters, the working control valve and the flow meters are arranged on the loop, the system further comprises control subsystems respectively connected with the controlled ends of the valve group, the first flow meters, the sensors, the working device, the working control valve and the flow meters, and the refrigerating capacity of the temperature control subsystems corresponding to the heat exchange devices on the pipeline of the inflation subsystem is gradually enhanced along the gas flowing direction.

Preferably, the system further comprises a vacuumizing subsystem, the vacuumizing subsystem is arranged on one branch of a tail end pipeline of the inflating subsystem, a vacuum pump and a vacuum control valve which enable the whole system to be in a vacuum state are arranged on the branch, and the control subsystem is further connected with the vacuum pump and the controlled end of the vacuum control valve.

The safety air release system is arranged on a branch of a tail end pipeline of the inflation subsystem, the branch comprises an air release control valve connected in series on the pipeline, a third one-way valve only allowing output from the inflation subsystem and safety valves connected in parallel at two ends of the air release control valve, a pipeline at the output end of the third one-way valve is connected with an air storage tank in a sealing mode, and the control subsystem is further connected with a controlled end of the air release control valve.

Preferably, the heat exchange device is in the form of a sleeve.

Optimized, the sensor includes temperature sensor group and pressure sensor, temperature sensor group is including measuring the temperature sensor at every heat transfer unit both ends, a temperature sensor of sharing on the pipeline between two adjacent heat transfer units, the pressure sensor sense terminal sets up in last heat transfer unit's output pipe.

Preferably, the control subsystem comprises N temperature control unitsSubsystem one-to-one correspondence of a plurality of heat exchange control units and iterative learning controller ILC₀；

The heat exchange control units respectively comprise a subtracter S, an iterative learning controller ILC and a proportional-integral-derivative controller PID;

iterative learning controller ILC₀The gas cylinder temperature detection device comprises two input ends and output ends, the number of the output ends is one less than that of the temperature control subsystems, and a reference value is input into one input end and is used for detecting the target temperature T of the gas cylinder_dThe other input end of the iteration learning controller ILC is connected with the input end of the Nth heat exchange control unit, and the output end of the iteration learning controller ILC is connected with the subtraction end of the subtractor S in the first N-1 heat exchange control units;

the number-reduced end of the number-reducing device S in the corresponding heat exchange control unit is respectively connected with the signal end of a temperature sensor arranged at the output end of the heat exchange device which acts correspondingly; the output end of the subtractor S is divided into two paths, one path is connected with the input end of the iterative learning controller ILC, the other path is connected with the PID through the PID, the output end of the iterative learning controller ILC is connected with the PID, and the PID in each heat exchange control unit is connected with the controlled end of the working control valve in the corresponding temperature control subsystem.

Preferably, the gas charging subsystem further comprises a first manual stop valve and a gas flow control valve which are arranged on a pipeline at the front end of the first heat exchange device, a second manual stop valve and a first one-way valve for preventing gas from flowing back, wherein the second manual stop valve and the first one-way valve are arranged on a pipeline at the rear end of the last heat exchange device.

Preferably, the number of the temperature control subsystems is 2, and the working device in the first temperature control subsystem is a constant-temperature water device.

Preferably, the working device in the second temperature control subsystem comprises a refrigerator and a buffer tank which form a loop, the buffer tank and the second heat exchange device form a loop, and the controlled end of the refrigerator is connected with the control subsystem.

The method for using the quick aeration precooling system comprises the following steps:

s1, before the experiment, the control subsystem controls the vacuum pump and the vacuum control valve to carry out circulating gas replacement on the inflation subsystem and the safe emptying subsystem until the gas purity requirement is met;

s2, opening a valve group in the inflation subsystem, filling gas into the test gas cylinder, and controlling the subsystem to obtain corresponding output electric signals of a first flowmeter, a first temperature sensor, a plurality of second temperature sensors and a pressure sensor which are arranged on a pipeline of the inflation subsystem;

s3, selecting different refrigeration effects, controlling different working devices to work, and performing iterative learning on the controller ILC₀Output temperature reference signal T_dIn a subtracter S in a correspondingly opened working device, an iterative learning controller IIC in a corresponding heat exchange control unit is used for realizing an expected temperature value in a corresponding temperature control subsystem, and all heat exchange control units calculate the opening degree of a corresponding working control valve through a PID algorithm so as to control the flow in the corresponding temperature control subsystem;

and S4, after the experiment is finished, actively releasing pressure by the control subsystem through the emptying control valve, and releasing high-pressure gas to the gas storage tank.

The invention has the advantages that:

(1) according to the invention, through the arrangement of the N temperature control subsystems and the control system, and the refrigeration capacity of the temperature control subsystems arranged along the inflation direction is gradually enhanced, the graded precooling for quickly and accurately adjusting the temperature of the gas at the inlet of the test gas cylinder is realized, and the flow rate of the gas is controlled through the valve bank on the inflation subsystem.

(2) The vacuum subsystem is used for ensuring the whole gas environment and the purity of the gas.

(3) The safety emptying subsystem is used for balancing the pressure of the whole inflation subsystem pipeline, and the gas storage tank is used for storing gas released due to the balanced pressure, so that resources are saved, and the environment can be protected.

(4) The sleeve may be used to isolate the inflation line from the pre-cooled line.

(5) The temperature sensor can provide different temperatures and initial temperatures when the pipeline passes through the heat exchange device in the air charging subsystem for the precooling system, the pressure sensor is used for testing the pressure in the pipeline, the basis is provided for controlling the opening degree of the emptying control valve of the subsystem, and safety valves are connected in parallel at two ends of the emptying control valve, so that the control subsystem is prevented from being incapable of normally functioning, and the dual protection effect is achieved.

(6) And the automatic real-time regulation of the temperature and the flow is realized through an iterative learning controller IIC and a proportional-integral-derivative controller PID.

(7) The setting of first manual stop valve and the manual stop valve of second can close the gas of whole subsystem pipeline of aerifing, can close from the source, also can close from test gas cylinder, can realize different demands, and the setting of first check valve can prevent gas reflux.

(8) The constant temperature water device can realize normal temperature precooling, the cooperation of the refrigerator and the buffer tank realizes low temperature precooling, the normal temperature precooling can work independently, and the normal temperature precooling and the low temperature precooling work cooperatively, so that the normal temperature precooling can play a role in improving the low temperature precooling effect.

(9) The method can realize the cyclic fatigue test of the test gas cylinder and can realize the detection of the test gas cylinder under the conditions of different temperatures and different flow rates.

Drawings

Fig. 1 is a system diagram of a rapid aeration pre-cooling system of the present invention.

Fig. 2 is a partial schematic view of the rapid aeration pre-cooling system of fig. 1.

The notations in the figures have the following meanings:

1-gas flow control valve 2-first flowmeter 3-first manual stop valve

4-first temperature sensor 5-first heat exchange device 6-second temperature sensor

7-second heat exchange device 8-third temperature sensor 9-pressure sensor

10-second manual stop valve 11-first one-way valve 12-third manual stop valve

13-second flow meter 14-first work control valve 15-thermostatic water device

16-fourth manual stop valve 17-third flow meter 18-second working control valve

19-buffer tank 20-refrigerator

21-second one-way valve 22-vacuum pump 23-vacuum control valve

24-safety valve 25-blow-down control valve 26-third check valve 27-control subsystem

Detailed Description

Example 1

As shown in fig. 1, the rapid aeration pre-cooling system includes an aeration subsystem, N temperature control subsystems, a vacuumizing subsystem, and a safety venting subsystem, wherein the vacuumizing subsystem is disposed on one branch of a terminal pipeline of the aeration subsystem, and the safety venting subsystem is disposed on the other branch of the terminal pipeline of the aeration subsystem. And heat exchange devices which correspond to the N temperature control subsystems one to one are arranged on pipelines of the air charging subsystems, and the heat exchange devices are in a sleeve form. In this embodiment, the number of the control temperature control subsystems is 2, and the control temperature control subsystems are respectively a first control subsystem 27 and a second temperature control subsystem, that is, the heat exchange device includes a first heat exchange device 5 and a second heat exchange device 7 respectively corresponding to the first control subsystem 27 and the second temperature control subsystem. The system takes hydrogen charging as an example, and the control subsystem 27 uses an industrial personal computer.

The inflation subsystem is also provided with a valve group, a first flowmeter 2 and a sensor, the front section of the inflation system is connected with a high-pressure tank, and the tail end of a pipeline is also connected with a test gas cylinder; the first temperature control subsystem comprises a first working device forming a loop with the corresponding first heat exchange device 5, a first working control valve 14, a second flow meter 13 and a third manual stop valve 12 which are arranged on the loop, the second temperature control subsystem further comprises a second working device forming a loop with the second heat exchange device 7, a second working control valve 18, a third flow meter 17 and a fourth manual stop valve 16 which are arranged on the loop, the system further comprises a control subsystem 27 respectively connected with the controlled ends of the valve bank, the first flow meter 2, the sensor, the first working device, the first working control valve 14, the second flow meter 13, the second working device, the second working control valve 18 and the third flow meter 17, and the refrigerating capacity of the temperature control subsystem corresponding to the 2 heat exchange devices on the pipeline of the gas charging subsystem is gradually enhanced along the gas flowing direction.

In this embodiment, the first working device is a constant temperature water device 15, constant temperature water is output through the constant temperature water device 15, the constant temperature water enters the shell pass of the second heat exchange device 7 through flow control to control the temperature of hydrogen in the tube pass of the first heat exchange device 5 so as to reach a stable state, and the water after heat exchange returns to the constant temperature water device 15 again; the outlet temperature of the high-pressure tank which is instantaneously changed is controlled by changing the flow rate of the constant-temperature water through flow control. The second working device comprises a refrigerator 20 and a buffer tank 19 which form a loop, the buffer tank 19 and the second heat exchange device 7 form a loop, and the controlled end of the refrigerator 20 is connected with the control subsystem 27.

The sensor includes temperature sensor group and pressure sensor 9, temperature sensor group sets up first temperature sensor 4 and second temperature sensor 6 on 5 input and output pipelines of first heat transfer device, sets up the third temperature sensor 8 on 7 output pipelines of second heat transfer device mutually, the 9 sense terminals of pressure sensor sets up in the output pipe of second heat transfer device 7.

The branch where the vacuumizing subsystem is located is provided with a vacuum pump 22, a vacuum control valve 23 and a second one-way valve 21 which enable the whole system to be in a vacuum state, the control subsystem 27 is further connected with the controlled ends of the vacuum pump 22 and the vacuum control valve 23, and the second one-way valve 21 only allows gas to be output from the pipeline of the inflating subsystem.

The branch of the emptying subsystem comprises an emptying control valve 25, a third one-way valve 26 and a safety valve 24, wherein the emptying control valve 25 is connected in series with the pipeline, the third one-way valve 26 only allows output from the gas charging subsystem, the safety valve 24 is connected in parallel with two ends of the emptying control valve 25, the pipeline at the output end of the third one-way valve 26 is connected with a gas storage tank in a sealing mode, and the control subsystem 27 is further connected with the controlled end of the emptying control valve 25.

As shown in fig. 2, the control subsystem 27 includes a first heat exchange control unit and a second heat exchange control unit corresponding to the first temperature control subsystem and the second temperature control subsystem one by one, and an iterative learning controller ILC₀；

The first heat exchange control unit comprises a subtracter S₁Iterative learning controller ILC₁Proportional-integral-derivative controller PID₁(ii) a The second heat exchange control unit comprises a subtracter S₂Iterative learning controller ILC₂Proportional-integral-derivative controller PID₂；

Iterative learning controller ILC₀Comprises two input ends and 1 output end, wherein one input end inputs a reference value which is used for detecting the target temperature T of the gas cylinder_dThe other input end is connected with the iterative learning controller ILC₁Is connected with the input end of the subtractor S in the first heat exchange control unit₁The reducing end of (a) is connected. Subtracting device S₁Is connected with the signal end of the second temperature sensor 6, and the number reducer S₂Is connected to the signal terminal of the third temperature sensor 8.

Subtractor S₁The output end of the controller is divided into two paths, one path is connected with the iterative learning controller ILC₁Is connected with the input end of the controller, and the other path passes through a proportional-integral-derivative controller PID₁Connected, iterative learning controller ILC₁And proportional-integral-derivative controller PID₁PID controller in the first heat exchange control unit₁Connected to the controlled end of the first work control valve 14. The second temperature sensor 6 detects the temperature value of the outlet of the second heat exchange device 7 and transmits the temperature value to the subtracter S₁In, subtracter S₁The outlet temperature value of the second heat exchange device 7 on the pipeline of the air charging subsystem is subjected to difference operation with the reference temperature value, and the operation result is transmitted to the iterative learning controller ILC₁Proportional-integral-derivative controller PID₁. And dynamically setting the PID parameters through an ILC algorithm, and correcting the actual outlet temperature value of the first heat exchange device 5 by adjusting the reference constant-temperature water flow regulation input signal through the PID algorithm to gradually approach the outlet temperature signal of the first heat exchange device 5 to the expected reference input signal so as to enable the profile error to tend to zero.

The specific control formula is as follows:

subtractor S for k-th operation of system₁Outputting the actual value of the outlet temperature of the first heat exchange device 5 and the reference valueDeviation e_1(k)(t)：

e_1(k)(t)＝T_d1(k)-T_1(k)(t)

Wherein, T_d1(k)Is a reference value T of the outlet temperature of the first heat exchange device 5 during the k-th operation of the system_1(k)(t) is the actual value of the outlet temperature of the first heat exchange device 5 on the charging subsystem pipeline during the k-th operation of the system. Requiring the system to operate at time T e 0, T]T of the real time temperature transmitted by the inner second temperature sensor 6_1(k)(T) tracking the desired output T_d1(k)。

By iterative learning controller ILC₁And (3) dynamically setting PID parameters:

K_1(k+1)(t)＝L₁[K_1(k)(t),e_1(k)(t)]

I_1(k+1)(t)＝L₁[I_1(k)(t),e_1(k)(t)]

D_1(k+1)(t)＝L₁[D_1(k)(t),e_1(k)(t)]

wherein L is₁To learn law, K₁、I₁And D₁The proportional amplification factor, the integral time and the differential time of the first heat exchange control unit are respectively.

Adjusting the constant-temperature water flow adjusting input signal through a PID algorithm:

wherein v is_1(k)(t) constant temperature water flow rate adjusting input signal v at K-th operation_1(k+1)And (t) is a constant-temperature water flow regulating input signal during the K +1 th operation.

Subtractor S₂The output end of the controller is divided into two paths, one path is connected with the iterative learning controller ILC₂Is connected with the input end of the controller, and the other path passes through a proportional-integral-derivative controller PID₂Connected, iterative learning controller ILC₂And proportional-integral-derivative controller PID₁PID controller in the second heat exchange control unit₂And the second workerIs connected to the controlled end of the control valve 18. The refrigerator 20 adopts a refrigerant refrigeration mode, refrigerants are pre-stored in the buffer tank 19, enter the second heat exchange device 7 through the flow control device to control the temperature of hydrogen on the hot side so as to reach a stable state, and the refrigerants after heat exchange circulate to the refrigerator; the inlet temperature of the second heat exchange device 7 is adjusted in an express way by changing the flow of the refrigerant through flow control. The third temperature sensor 8 detects the temperature value of the outlet of the second heat exchange device 7 on the pipeline of the air charging subsystem and transmits the temperature value to the subtracter S₂In, subtracter S₂Carrying out difference operation on the outlet temperature value of the second heat exchange device 7 and the reference temperature value, and transmitting the operation result to the iterative learning controller ILC₂Proportional-integral-derivative controller PID₂. And dynamically setting the PID parameters through an ILC algorithm, adjusting the reference refrigerant flow adjustment input signal through the PID algorithm, and correcting the outlet temperature value of the actual second heat exchange device 7 on the inflatable subsystem pipeline to enable the outlet temperature signal of the second heat exchange device 7 on the inflatable subsystem pipeline to gradually approach the expected reference input signal.

The basic control formula is as follows:

subtractor S for k-th operation of system₂Outputting the deviation e between the actual value and the reference value of the outlet temperature of the second heat exchange device 7_2(k)(t)：

e_2(k)(t)＝T_d(k)-T_2(k)(t)

Wherein, T_d(k)Is a reference value of the outlet temperature of the second heat exchange device 7 when the system runs for the kth time, namely the target temperature T of the detected gas cylinder_2(k)(t) is the actual value of the outlet temperature of the second heat exchange device 7 on the charging subsystem pipeline when the system operates at the kth time. Requiring the system to operate at time T e 0, T]T of the real time temperature transmitted by the inner third temperature sensor 8_2(k)(T) tracking the desired output T_d(k)。T_2(k)(T) using T in FIG. 2₂And (4) showing.

By iterative learning controller ILC₂And (3) dynamically setting PID parameters:

K_2(k+1)(t)＝L₂[K_2(k)(t),e_2(k)(t)]

I_2(k+1)(t)＝L₂[I_2(k)(t),e_2(k)(t)]

D_2(k+1)(t)＝L₂[D_2(k)(t),e_2(k)(t)]

wherein L is₂To learn law, K₂、I₂And D₂The second heat exchange control unit is respectively used for proportional amplification factor, integral time and differential time.

Adjusting the refrigerant flow through a PID algorithm to adjust an input signal:

wherein v is_2(k)(t) is a refrigerant flow regulation input signal at the Kth operation, v_2(k+1)And (t) is a refrigerant flow regulating input signal when the K +1 th operation is performed.

The automatic control subsystem comprises an industrial personal computer, and the industrial personal computer controls the opening and closing of the pneumatic control valve to automatically control through feedback signals of the temperature sensor and the pressure sensor in each system. Iterative learning controller ILC₀Input terminal and subtracter S₂Output end, target temperature T in test gas cylinder_dConnected, iterative learning controller ILC₀Output terminal and subtracter S₁Is connected to the input terminal of the controller. By iterative learning controller ILC₀And dynamically distributing the reference temperature value of the outlet of the water cooling device. The basic control formula is as follows:

subtractor S₂Outputting the deviation between the actual value of the outlet temperature of the second heat exchange device and the reference value:

e_2(k)(t)＝T_d(k)-T_2(k)(t)

wherein, T_d(k)For testing the reference value of the temperature, T, in the cylinder_2(k)(t) is the actual value of the second heat exchange means outlet temperature and subscript k indicates the kth operating value. Requiring the system to operate at time T e 0, T]T of the real time temperature transmitted by the inner third temperature sensor 8_2(k)(T) tracking the desired output T_d(k)。T_2(k)Using T in FIG. 2₂And (4) showing.

By iterative learning controller ILC₀Dynamically distributing the outlet reference temperature value of the water cooling device:

T_d1(k)＝L₀[T_d(k),e_2(k)(t)]

wherein L is₀To learn law, T_d1(k)Is a reference value, T, of the outlet temperature of the first heat exchange means 5_d(k)To test the temperature reference value in the gas cylinder.

The valve group in the air charging subsystem comprises a first manual stop valve 3, a gas flow control valve 1, a second manual stop valve 10 and a first one-way valve 11, wherein the first manual stop valve 3, the gas flow control valve 1 and the second manual stop valve 10 are arranged on a pipeline at the front end of the first heat exchange device 5, and the first one-way valve 11 is used for preventing gas from flowing back.

And gas in the high-pressure tank enters the test gas cylinder for charging by opening the gas flow control valve 1, the first heat exchange device 5 and the second heat exchange device 7 in sequence. The duration and the pressure boosting rate of the hydrogen charging process are controlled by a flow control valve, a flow meter, a control subsystem 27 and a safe emptying subsystem; the temperature of the inlet of the second heat exchange device 7 is kept constant under the action of the first temperature control subsystem through the first heat exchange device 5; the temperature of the inlet of the test gas cylinder is rapidly reduced to-40 ℃ through the second heat exchange device 7 and is kept stable.

Example 2

A method of using the rapid aeration pre-cooling system of example 1, comprising the steps of:

s1, before the experiment, the control subsystem 27 controls the vacuum pump 22 and the vacuum control valve 23 to perform circulating gas replacement on the air charging subsystem and the safety emptying subsystem until the requirement of gas purity is met.

And S2, opening a valve group in the inflation subsystem, filling gas into the test gas cylinder, and obtaining corresponding output electric signals of the first flowmeter 2, the first temperature sensor 4, the plurality of second temperature sensors 6 and the pressure sensor 9 which are arranged on a pipeline of the inflation subsystem by the control subsystem 27.

S3, selecting different refrigeration effects, controlling different working devices to work, and performing iterative learning on the controller ILC₀Outputting a temperature reference signal to a corresponding onIn the subtracter S of the working device, the iteration learning controller IIC in the corresponding heat exchange control unit is used for realizing the expected temperature value in the corresponding temperature control subsystem, and all the heat exchange control units calculate the opening degree of the corresponding working control valve through a PID algorithm so as to control the flow in the corresponding temperature control subsystem.

And S4, after the experiment is finished, actively relieving pressure by the control subsystem 27 through the air release control valve 25, and releasing high-pressure gas to the gas storage tank.

In step S3, when the refrigeration effect is selected to be normal temperature refrigeration, the gas flow control valve 1, the first manual stop valve 3, and the second manual stop valve 10 are opened, and the high-pressure gas source in the high-pressure tank is used to fill hydrogen into the test gas cylinder; meanwhile, the control subsystem 27 monitors the inlet flow, the inlet temperature and the outlet temperature of the second heat exchange device 7 on the pipeline of the inflation subsystem, the inlet temperature and the outlet temperature of the test gas cylinder, the inlet temperature and the pressure of the test gas cylinder and the outlet flow of the constant temperature water device 15 through the first flow 2, the first temperature sensor 4, the second temperature sensor 6, the third temperature sensor 8, the pressure sensor 9 and the second flowmeter 13 respectively; the control subsystem 27 controls the hydrogen charge flow and pressure by adjusting the gas flow control valve 1 according to the measurements of the first flow meter 2 and the pressure sensor 9; the control subsystem 27 transmits the measured values of the first temperature sensor 4, the second temperature sensor 6 and the second flow meter 13 to the subtractor S₁In, subtracter S₁The outlet temperature value of the second heat exchange device 7 on the pipeline of the air charging subsystem is subjected to difference operation with the reference temperature value, and the operation result is transmitted to the iterative learning controller ILC₁Proportional-integral-derivative controller PID₁. Dynamically setting PID parameters through an ILC algorithm, adjusting a constant-temperature water flow adjusting input signal through the PID algorithm, correcting an actual outlet temperature value of the first heat exchange device 5, adjusting the first working control valve 14 to control the flow of constant-temperature water, and enabling an outlet temperature signal of the second heat exchange device 7 on a pipeline of the inflatable subsystem to gradually approach an expected reference input signal so as to achieve stable outlet temperature of the first heat exchange device 5 and keep the outlet temperature at 15-25 ℃.

When the refrigeration effect is selected to be low-temperature refrigeration, the gas flow control valve 1 and the first valve are openedThe manual stop valve 3 and the second manual stop valve 10 are used for filling hydrogen into the test gas cylinder by utilizing a high-pressure gas source in the high-pressure tank; meanwhile, the control subsystem 27 monitors the inlet flow and temperature of the second heat exchange device 7, the outlet temperature and pressure, the outlet flow of the constant temperature water device 15 and the inlet refrigerant flow of the second heat exchange device 7 respectively through the first flowmeter 2, the first temperature sensor 4, the second temperature sensor 6, the third temperature sensor 8, the pressure sensor 9, the second flowmeter 13 and the third flowmeter 17; by iterative learning controller ILC₀And dynamically distributing the reference temperature value of the outlet of the first heat exchange device 5 and the reference temperature value of the outlet of the second heat exchange device 7. The control subsystem 27 controls the hydrogen charge flow and pressure by adjusting the gas flow control valve 1 according to the measurements of the first flow meter 2 and the pressure sensor 9; the control subsystem 27 controls the flow rate of the thermostatic water by adjusting the first work control valve 14 to reach a stable outlet temperature of the first heat exchange means 5 and maintain it at about 15 ℃ (± 2 ℃); the control subsystem 27 transmits the measured values of the second temperature sensor 6, the third temperature sensor 8 and the third flow meter 17 to the subtractor S2, and the control subsystem 27 adjusts the second working control valve 18 to control the storage amount of the refrigerant in the buffer tank 19 and the flow rate of the refrigerant entering the second heat exchanging device 7, so that the output temperature signal of the second heat exchanging device 7 gradually approaches the expected reference input signal, and the outlet temperature of the second heat exchanging device 7 is rapidly reduced to about-40 ℃ (± 2 ℃) and is kept stable.

The invention adopts a grading precooling mode of water cooling (front stage) and refrigerant precooling (rear stage) aiming at the condition that the pressure, the temperature and the flow of the outlet of the high-pressure storage tank are constantly changed. The first heat exchange device 5 and the first temperature control subsystem keep the inlet temperature of the second heat exchange device 7 stable or realize the test process of normal-temperature precooling by adjusting the flow of the constant-temperature water. The second temperature control subsystem enables the temperature of the outlet of the second heat exchange device 7 to be rapidly reduced to be near-40 ℃ in a mode of storing refrigerants and adjusting flow, and the temperature is kept stable; while reducing the power, volume and cost of the chiller 20. The invention solves the bottleneck problem of precooling requirements under variable working conditions in a vehicle-mounted gas cylinder hydrogen circulation fatigue test, and provides a graded precooling control method in a rapid hydrogen charging process.

Aiming at the working conditions of variable temperature and variable flow at the outlet of the high-pressure tank, the circulation interval (the circulation period of the hydrogen charging and discharging process of the whole system is more than 30min, wherein the hydrogen charging process is 3-5 min, and the hydrogen discharging process is more than 30min) is fully utilized, a buffer tank 19 is additionally arranged between a refrigerator and a second heat exchange device 7 to pre-store a refrigerant, and the flow of the refrigerant is controlled by utilizing a regulating valve, so that the inlet temperature of a tested gas cylinder can be quickly reduced to be near-40 ℃ and kept stable; and reduces the power, volume and cost of the chiller 20.

The invention is not to be considered as limited to the specific embodiments shown and described, but is to be understood to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

Claims

1. A pre-cooling method for a fast-inflating pre-cooling system, characterized in that, the fast-inflating pre-cooling system comprises an inflatable subsystem and two temperature control subsystems, and the pipeline of the inflatable subsystem is provided with two temperature control subsystems. The temperature subsystem is one-to-one corresponding to two heat exchange devices. The front end of the gas charging subsystem is connected to the high-pressure tank. The pipeline of the gas charging subsystem is also provided with a valve group, a first flow meter (2), and a sensor. At the end of the pipeline A test gas cylinder is also connected;

The two temperature control subsystems are respectively a first temperature control subsystem and a second temperature control subsystem, and the two heat exchange devices are respectively a first heat exchange device (5) and a second heat exchange device (7); The temperature subsystem includes a first working device forming a loop with the corresponding first heat exchange device (5), a first working control valve (14), a second flow meter (13), a third manual control valve (14) arranged on the loop A stop valve (12), the second temperature control subsystem further includes a second working device forming a loop with the second heat exchange device (7), a second working control valve (18), a third flow rate and a second working control valve (18) arranged on the loop meter (17), a fourth manual shut-off valve (16); the rapid charge pre-cooling system further includes a valve group, a first flow meter (2), a sensor, a first working device, a first working control valve (14), The second flowmeter (13), the second working device, the second working control valve (18) and the control subsystem (27) connected to the controlled end of the third flowmeter (17), along the gas flow direction, the first The heat exchange device (5) and the second heat exchange device (7) are arranged in sequence on the gas-filled subsystem pipeline, and along the gas flow direction, the temperature control subsystems corresponding to the two heat-exchange devices on the gas-filled subsystem pipeline The cooling capacity is gradually increased;

The valve group in the inflatable subsystem includes a gas flow control valve (1), a first manual shut-off valve (3), and a gas flow control valve (3) sequentially arranged on the front-end pipeline of the first heat exchange device (5), and a second heat exchange device in sequence. A second manual shut-off valve (10) on the rear pipeline of the device (7) and a first one-way valve (11) for preventing gas backflow;

The first flow meter (2) is arranged between the gas flow control valve (1) and the first manual stop valve (3);

The rapid charging and pre-cooling system further includes a vacuum pumping subsystem, which is arranged on a branch of the end pipeline of the gas charging subsystem. a control valve (23), the control subsystem (27) is also connected with the vacuum pump (22) and the controlled end of the vacuum control valve (23);

The rapid charge pre-cooling system further includes a safety venting subsystem, the safety venting subsystem is arranged on a branch of the end pipeline of the charging subsystem, and the branch includes a venting control valve (25) connected in series on the pipeline and a vent control valve (25) that only allows A third one-way valve (26) output from the inflation subsystem, a safety valve (24) connected in parallel at both ends of the venting control valve (25), and a gas storage tank is sealed and connected to the pipeline at the output end of the third one-way valve (26). The control subsystem (27) is also connected with the controlled end of the venting control valve (25);

The sensor includes a temperature sensor group and a pressure sensor (9), the temperature sensor group includes a first temperature sensor (4) and a second temperature sensor respectively arranged on the input end and the output end pipeline of the first heat exchange device (5) Sensor (6), a third temperature sensor (8) arranged on the pipeline of the output end of the second heat exchange device (7), the detection end of the pressure sensor (9) is arranged at the output end of the second heat exchange device (7) inside the tube;

The control subsystem (27) includes a first heat exchange control unit and a second heat exchange control unit corresponding to the first temperature control subsystem and the second temperature control subsystem, and an iterative learning controller ILC ₀ ;

The first heat exchange control unit includes a subtractor S ₁ , an iterative learning controller ILC ₁ , and a proportional-integral-derivative controller PID ₁ ; the second heat exchange control unit includes a subtractor S ₂ , an iterative learning controller ILC _2. Proportional-integral-derivative controller PID ₂ ;

The iterative learning controller ILC ₀ includes two input terminals and one output terminal, wherein the first input terminal is input with a reference value, this reference value is the target temperature T _d of the test gas cylinder, and the second input terminal is connected with the subtractor S ₂ . The output end is connected, and the output end is connected with the subtrahend end _of the subtractor S1 in the _first heat exchange control unit; _The minuend end of the device S2 is connected with the signal end of the third temperature sensor (8);

The output end of the subtractor S ₁ is divided into two paths, one is connected to the input end of the iterative learning controller ILC ₁ , and the other is connected to the proportional-integral-derivative controller PID ₁ , and the output end of the iterative learning controller ILC ₁ is connected to the proportional- The integral-derivative controller PID ₁ is connected, and the proportional-integral-derivative controller PID ₁ in the first heat exchange control unit is connected with the controlled end of the first work control valve (14); the second temperature sensor (6) detects the first The temperature value at the outlet of a heat exchange device (5) is transmitted to the subtractor S1, and the subtractor S1 makes _a difference between the outlet temperature value of the _first heat exchange device (5) on the gas-filled subsystem pipeline and the reference temperature value operation, and transmit the operation result to iterative learning controller ILC ₁ , proportional-integral-derivative controller PID ₁ ;

The working device in the first temperature control subsystem is a constant temperature water device (15);

The working device in the second temperature control subsystem includes a refrigerator (20) forming a loop and a buffer tank (19), the buffer tank (19) and the second heat exchange device (7) forming a loop, the refrigeration The controlled end of the machine (20) is connected with the control subsystem (27);

The method for using the rapid charging pre-cooling system includes the following steps:

S1. Before the experiment, use the control subsystem (27) to control the vacuum pump (22) and the vacuum control valve (23) to perform circulating gas replacement for the inflation subsystem and the safety venting subsystem until the gas purity requirements are met;

S2. Open the valve group in the inflation subsystem, fill the test gas cylinder with gas, and control the subsystem (27) to obtain the first flow meter (2), the first temperature sensor (4), The corresponding output electrical signals of the second temperature sensor (6) and the pressure sensor (9);

S3. Select different cooling effects, control different working devices to work, the iterative learning controller ILC ₀ outputs a temperature reference signal to the subtractor S in the corresponding open working device, and through the iterative learning controller in the corresponding heat exchange control unit The IIC realizes the desired temperature value in the corresponding temperature control subsystem, and all heat exchange control units calculate the opening of the corresponding working control valve through the PID algorithm to control the flow rate in the corresponding temperature control subsystem;

S4. After the experiment is completed, the control subsystem (27) actively releases the pressure through the venting control valve (25), and releases the high-pressure gas to the gas storage tank;

In step S3, when the cooling effect is selected to be room temperature refrigeration, the gas flow control valve (1), the first manual cut-off valve (3), and the second manual cut-off valve (10) are opened, and the high-pressure gas source in the high-pressure tank is used to The test gas cylinder is filled with hydrogen; at the same time, the control subsystem (27) passes through the first flow rate (2), the first temperature sensor (4), the second temperature sensor (6), the third temperature sensor (8), the pressure sensor ( 9) and the second flow meter (13) respectively monitor the inlet flow, inlet temperature, outlet temperature, inlet temperature and pressure of the test gas cylinder, and the outlet of the constant temperature water device (15) on the pipeline of the inflation subsystem of the first heat exchange device (5). Flow; the control subsystem (27) controls the hydrogen charging flow and pressure by adjusting the gas flow control valve (1) according to the measured values of the first flow meter (2) and the pressure sensor (9); the control subsystem (27) will The measured values of the first temperature sensor (4), the second temperature sensor (6) and the second flowmeter (13) are transmitted to the subtractor S1, and the subtractor S1 converts the _first heat exchange device ( ₅ ) into the gas The difference operation is performed between the outlet temperature value and the reference temperature value on the subsystem pipeline, and the operation result is transmitted to the iterative learning controller ILC ₁ and the proportional-integral-derivative controller PID ₁ ; the PID parameters are dynamically adjusted by the ILC algorithm, and the The PID algorithm adjusts the constant temperature water flow to adjust the input signal, corrects the actual first heat exchange device (5) outlet temperature value, and adjusts the first work control valve (14) to control the constant temperature water flow, so that the first heat exchange device (5) is in the The outlet temperature signal on the gas charging subsystem pipeline gradually approaches the desired reference input signal, so as to achieve a stable outlet temperature of the first heat exchange device (5), and keep it between 15 and 25°C;

When the cooling effect is selected as low-temperature refrigeration, open the gas flow control valve (1), the first manual stop valve (3), and the second manual stop valve (10), and use the high-pressure gas source in the high-pressure tank to charge the test gas cylinder. Hydrogen injection; at the same time, the control subsystem (27) passes the first flow meter (2), the first temperature sensor (4), the second temperature sensor (6), the third temperature sensor (8), the pressure sensor (9), the The second flowmeter (13) and the third flowmeter (17) monitor the inlet flow and temperature, outlet temperature and pressure of the second heat exchange device (7), the outlet flow of the constant temperature water device (15) and the second heat exchange device (7) respectively. ) inlet refrigerant flow; the reference temperature value at the outlet of the first heat exchange device (5) and the reference temperature value at the outlet of the second heat exchange device (7) are dynamically allocated through the iterative learning controller ILC ₀ ; the control subsystem (27) According to the measured values of the first flow meter (2) and the pressure sensor (9), the hydrogen charging flow and pressure are controlled by adjusting the gas flow control valve (1); the control subsystem (27) adjusts the first work control valve (14) by adjusting ) to control the flow rate of constant temperature water to achieve a stable outlet temperature of the first heat exchange device (5) and keep it at 15±2°C; the control subsystem (27) connects the second temperature sensor (6), the third temperature sensor (8) and the measured values of the third flow meter (17) are transmitted to the subtractor S2, and the control subsystem (27) adjusts the _second work control valve (18) to control the amount of refrigerant in the buffer tank (19) and The flow of refrigerant entering the second heat exchange device (7) makes the output temperature signal of the second heat exchange device (7) gradually approach the desired reference input signal, so that the outlet temperature of the second heat exchange device (7) is rapidly reduced to -40± 2°C and remained stable.

2 . The pre-cooling method of the rapid charge pre-cooling system according to claim 1 , wherein the heat exchange device is in the form of a sleeve. 3 .