Fuel cell test platform power consumption reduction control system and control method

Abstract

The present invention belongs to the technical field of fuel cell testing, and discloses a fuel cell testing platform power consumption reduction control system and control method. The system includes a heat recovery heat exchange part and a temperature control heat exchange implementation part. The high-power heating module of the heat recovery heat exchange part is respectively connected to a water mixing module and a liquid circulation device. The liquid circulation device is connected to a heat exchange module A, and the heat exchange module A is connected to a cold water unit A and a switch valve A, and is connected to the water mixing module; the water mixing module of the temperature control heat exchange implementation part is connected to a heat exchange module C, and the heat exchange module C is connected to a circulating liquid container, and the circulating liquid container is connected to a liquid circulation device, and the liquid circulation device is connected to a heat exchange module B, and the heat exchange module B is connected to a fuel cell stack to be tested; the upper computer control system is connected in series with the lower computer control system, and is linked to the above-mentioned structures. The present invention achieves the purpose of reducing power consumption of the fuel cell testing platform, and the energy control is accurate, convenient, and more efficient.

Description

Technical Field

[0001] The invention belongs to the technical field of fuel cell testing, and relates to a power consumption reduction control system and a control method for a fuel cell testing platform. Background Art

[0002] As a new type of clean energy that can directly convert chemical energy into electrical energy, hydrogen fuel cells have become an important part of new energy. With the rapid development of the hydrogen energy industry today, not only a large amount of manpower and material resources must be invested in the research and development and production of high-stability fuel cell stacks, but also a scientific research and development layout is needed for the corresponding detection systems and supporting equipment. With the increase in the application of hydrogen fuel cells in ships and other scenarios, the matching of high-power fuel cell stack test benches has become imperative. Due to the power constraints on many customer sites, it is impossible to provide the stable or instantaneous high-power output required by the high-power test bench, which to a certain extent limits the production of high-power fuel cell modules.

[0003] The high power of the fuel cell test bench is mainly used for heating and humidification. The fuel cell stack test bench is the main equipment used to calibrate the performance of the fuel cell stack. It has very high requirements on the test capability. Generally, during the operation of the fuel cell stack, the gases in the hydrogen and air paths need to be heated and humidified. The fuel cell stack test bench needs to ensure the temperature rise rate and dew point capability. For dry air of about 10,000L / MIN, under the premise of ensuring the rate and dew point, the air humidification power is more than 140 kilowatts, and it fluctuates instantaneously. If the hydrogen is also humidified, it should be more than 60 kilowatts. Under general factory conditions, the power supply capacity is up to 500A. When a factory with a small power capacity runs a high-power test bench, the electrical system at the upper end of the factory will be abnormal or trip, resulting in power accidents.

[0004] The fuel cell stack test bench usually adopts the bubbling + spraying method of the humidification tank. The gas is humidified by water heated by the heater for primary humidification, and then humidified by the spray system for secondary humidification to achieve the state before the gas enters the reaction. The core part is that hydrogen and air must be equipped with independent high-power heaters. The electric heater is controlled by the relay controlled by the lower computer temperature control system for heating. When the temperature difference is large, the high-power heater is heated at full power, and the electric power is very large; when the temperature is similar, due to the PID setting of the temperature and the temperature fluctuation caused by gas circulation or water replenishment, the relay will generate a large instantaneous power, resulting in the instantaneous power exceeding the electrical load, or the overall power supply capacity. The conventional solution is to group the heaters from the electrical control to reduce the instantaneous power consumption, but because the test sometimes involves a substantial increase, the grouping cannot meet the heating time requirements.

[0005] The temperature of the circulating water circuit of a conventional fuel cell test platform is controlled by peripheral chilled water through a heat exchanger unit, and is not recycled as comprehensive heat energy of the test bench.

[0006] For example, CN113078334A is a fuel cell temperature control system compatible with different power stacks, including a PLC lower computer temperature control unit, an upper computer monitoring control unit, a circulating water loop and an electronic load; the circulating water loop includes circulating water, a stack inlet temperature sensor, a stack outlet temperature sensor, a water tank, a water pump, a flow sensor, a heater, a ring-fin radiator, a high-power cooling fan and a low-power cooling fan; it describes the temperature control mode of the hydrogen fuel cell engine system, which enables a small cycle at low temperatures, and dissipates heat through a high-power radiator at high temperatures, and controls the temperature through a thermostat. The present invention uses a high-power fuel cell stack test platform, which recovers the heat energy generated by the fuel cell under high-power test conditions to meet the gas warming requirements. The purpose of the fuel cell test platform is to calibrate the corresponding parameters with high precision. The function of the engine system is to output electrical energy to ensure the corresponding requirements of the fuel cell. Summary of the invention

[0007] With the development of the fuel cell industry, the production of high-power fuel cell stacks has increased, and the research and development testing and performance testing of high-power fuel cell stacks have become more important. In order to reduce the power consumption of the high-power fuel cell stack test bench, to make more reasonable use of electrical energy and thermal energy, and to make the fuel cell stack test bench more competitive, this high-power fuel cell stack test bench power consumption reduction system with simple structure, high precision and low cost was invented.

[0008] The above object of the present invention is achieved through the following technical solutions:

[0009] The power consumption reduction control system of the fuel cell test platform includes a heat recovery and heat exchange part and a temperature control and heat exchange implementation part. The high-power heating module of the heat recovery and heat exchange part is respectively connected to the water mixing module and the liquid circulation device A, the liquid circulation device A is connected to the heat exchange module A, the heat exchange module A is connected to the cold water unit A and the switch valve A, and is connected to the water mixing module; the water mixing module of the temperature control and heat exchange implementation part is connected to the heat exchange module C, the heat exchange module C is connected to the circulating liquid container, the circulating liquid container is connected to the liquid circulation device B, the liquid circulation device B is connected to the heat exchange module B, and the heat exchange module B is connected to the fuel cell stack under test; the upper computer control system is connected in series with the lower computer control system and linked to the above-mentioned structures.

[0010] Furthermore, the switch valve A controls the heat exchange module A to perform cold-heat exchange, and the switch valve B controls the heat exchange module B to perform cold-heat exchange.

[0011] Furthermore, a temperature feedback unit T01 is provided between the lower computer control system and the high-power heating module.

[0012] Furthermore, the heat recovery and heat exchange part determines whether to perform heat recovery based on the difference between the temperature feedback unit T02 and the temperature feedback unit T03, and controls the opening of the mixing water module according to the algorithm to perform the cold and heat exchange ratio to achieve heat recovery. When the temperature cannot be increased through heat recovery or there is no heat to be recovered, the upper computer control system executes the lower computer control system to use the high-power heating module for heating.

[0013] Furthermore, when the difference between the temperature feedback unit T02 and the temperature feedback unit T03 exceeds 2° C., the liquid circulation device A is started.

[0014] Furthermore, the algorithm is a PID control algorithm.

[0015] Furthermore, the expected temperature settings of the temperature feedback unit T01, the water mixing module, the heat exchange module C, and the liquid circulation device A constitute a thermal power recovery PID closed-loop control loop.

[0016] A fuel cell test platform power consumption reduction control method, a fuel cell test platform power consumption reduction control system controls the power of a liquid circulation device A, circulates the circulating liquid in the circulating liquid container, and reaches the set value of the temperature feedback unit T03 by controlling the switch valve B of the heat exchange module B. When the difference between the temperature feedback unit T02 and the temperature feedback unit T03 exceeds the set value, the liquid circulation device A is started, and the circulating liquid in the high-power heating module enters the heat exchange module A and the mixing valve flows back to the high-power heating module. The temperature feedback unit T01 on the high-power heating module provides real-time feedback, and the lower computer control system adjusts the heating power and frequency according to the difference between the demand value and the feedback value; when the high-power heating module needs to be cooled, the temperature controller of the lower computer control system does not work, and the upper computer control system starts the cooling logic, reduces the opening of the hot water side of the mixing module, increases the opening at the heat exchange module A, and opens the switch valve A to achieve rapid cooling.

[0017] The beneficial effects of the present invention compared with the prior art are:

[0018] The fuel cell test bench power consumption reduction system and control method of the present invention achieve the purpose of reducing power consumption of the fuel cell test bench. The fuel cell test bench of the present invention achieves a 90% power reduction during high-load testing. Combined with the group control of high-power heating, the upper limit of the power of the high-power test bench can be reduced by more than 60%. The test bench equipped with this system can perform high-power testing in factories with insufficient power or low capacity, and the energy control is accurate, convenient, and more efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0020] Figure 1 It is a schematic diagram of the control system structure;

[0021] Figure 2 It is a flow chart of the algorithm of the system of the present invention;

[0022] Figure 3 It is the heating power distribution diagram without heat recovery enabled;

[0023] Figure 4 It is the power distribution diagram of heating with heat recovery enabled.

[0024] In the figure: 1. high-power heating module; 2. liquid circulation device A; 3. heat exchange module A; 4. water mixing module; 5. heat exchange module C; 6. circulating liquid container; 7. liquid circulation device B; 8. heat exchange module B; 9. temperature feedback unit T01; 10. temperature feedback unit T02; 11. temperature feedback unit T03; 12. upper computer control system; 13. switch valve A; 14. switch valve B; 15. lower computer control system. DETAILED DESCRIPTION

[0025] The present invention is described in detail below by specific examples, but the protection scope of the present invention is not limited. Unless otherwise specified, the experimental methods used in the present invention are all conventional methods, and the experimental equipment, materials, reagents, etc. used can be obtained from commercial channels.

[0026] The high-power heating module 1 in this solution is the heating part of the humidification module of the fuel cell stack test bench. The temperature control system is mainly composed of two groups of heat exchange modules. The heat exchange module B8 is the temperature control and heat exchange implementation part, and the heat exchange module A5 is the heat recovery and heat exchange part. The heat recovery part is composed of the high-power heating module 1 and the liquid circulation device B7. Both components have a heat dissipation system for heat exchange with cold water.

[0027] During the test of the fuel cell stack test bench of this scheme, the temperature increase of the high-power heating module 1 is divided into two ways. One is that the upper computer control system 12 transmits the set temperature, and the output is executed through the temperature control system of the lower computer control system 15, and the high-power heating module 1 performs heating and temperature increase. The second is to heat up by recovering the heat energy of the circulating water of the fuel cell stack. The heat recovery of the original fuel cell circulating cooling water meets the power consumption reduction and instantaneous high power demand of the equipment. Through experimental testing, except for preheating, the high-power heating module 1 needs to be started when the load reduction temperature difference is insufficient, and the original heating power consumption of humidification is changed from the original instantaneous high power to 0.

[0028] The power consumption reduction system of the fuel cell stack test bench is composed of a host computer control system 12, a slave computer control system 15, a high-power heating module 1, a liquid circulation device A2, three heat exchange modules, a water mixing module 4, three temperature feedback units, two switch valves, etc. The host computer control system 12 is the brain of the entire test platform, and can control the functions and actions of the slave computer control system 15 and related actuators through input instructions and corresponding parameters of the temperature feedback unit.

[0029] When the fuel cell stack test platform tests the stack, the power consumption reduction control system of the fuel cell test platform controls the power of the liquid circulation device A2 to circulate the circulating liquid in the circulating liquid container 6, and controls the switch valve B14 of the heat exchange module B8 to realize the corresponding temperature demand of the temperature feedback unit T03 11. The difference between the temperature feedback unit T02 10 and the temperature feedback unit T03 11 is used to determine whether to perform heat recovery. When the temperature difference exceeds 2°C, the heat recovery logic is started, that is, the liquid circulation device A2 is started. After the liquid circulation device A2 is started, the circulating liquid in the high-power heating module 1 enters the heat exchange module A3 and the mixing valve flows back to the high-power heating module 1. The temperature feedback unit T01 9 on the high-power heating module 1 provides real-time feedback, and the lower computer control system 15 adjusts the heating power and frequency according to the difference between the demand value and the feedback value. When there is no heat recovery cycle, the power is always under the control of the lower computer temperature control system 15, resulting in high power and instantaneous consumption. When heat recovery is started, the high-power heating module 1 under the control of the temperature controller of the lower computer control system 15 basically does not work, mainly because the heat recovered from the heat energy is sufficient to meet the heat energy demand. When the high-power heating module 1 needs to be cooled down, the temperature controller of the lower computer control system 15 does not work, and the upper computer control system 12 starts the cooling logic, reduces the opening of the hot water side of the water mixing module 4, increases the opening at the heat exchange module A3, and opens the switch valve A13 to achieve rapid cooling.

[0030] Figure 1 The dotted line in the middle refers to the electrical signal communication, i.e. the control signal. The solid line is the pipeline connection, which is connected to the thread, chuck, ferrule, etc. of the stainless steel pipe.

[0031] The join order is:

[0032] (1) Heat recovery and heat exchange part: The high-power heating module 1 is connected to the water mixing module 4 and the liquid circulation device A2, the liquid circulation device A2 is connected to the heat exchange module 3A, the heat exchange module 3A is connected to the cold water unit A15 and the switch valve A13, and is connected to the water mixing module 4.

[0033] (2) Temperature control and heat exchange implementation part: the water mixing module 4 is connected to the heat exchange module C5, the heat exchange module C5 is connected to the circulating liquid container 6, the circulating liquid container 6 is connected to the liquid circulation device B7, the liquid circulation device B7 is connected to the heat exchange module B8, and the heat exchange module B8 is connected to the fuel cell stack under test. Example 1

[0034] Fuel cell test platform power consumption reduction control system combined with attached Figure 1-2 Further specific implementation instructions:

[0035] The present embodiment is a fuel cell test platform power consumption reduction control system, wherein the temperature feedback unit T019, the temperature feedback unit T0210, and the temperature feedback unit T0311 are AI signals. The fuel cell test platform power consumption reduction control system performs program control by reading the input AI signal and controlling the target logic. When the target value is greater than the set value of the temperature feedback unit T019, the fuel cell test platform power consumption reduction control system receives a temperature increase instruction, and the temperature increase path is performed by the lower computer control system 15 to perform heating and heat recovery. The control of the heat recovery and heat exchange part takes precedence over the high-power heating module 1. The heat recovery and heat exchange part is determined by the fuel cell test platform power consumption reduction control system according to the difference between the temperature feedback unit T0210 and the temperature feedback unit T0311, and the opening of the mixing water module 4 is controlled according to the scientific control logic and algorithm to perform the cold and heat exchange ratio to achieve heat recovery. When the temperature increase cannot be achieved through heat recovery or there is no heat to be recovered, the upper computer control system 12 executes the lower computer control system 15 to heat the high-power heating module 1.

[0036] The specific algorithm is as follows Figure 2 shown.

[0037] 1) PID control algorithm: u(t) = Kp * e(t) + Ki * ∫e(t) dt + Kd * de(t) / dt

[0038] u(t): output of the controller;

[0039] e(t): system deviation (difference between set value and actual value);

[0040] Kp: proportionality coefficient;

[0041] Ki: integration coefficient;

[0042] Kd: differential coefficient.

[0043] 2) The temperature difference parameter between the temperature feedback unit T02 10 and the temperature feedback unit T03 11 is used as a precondition for starting the heat recovery system.

[0044] 3) The expected temperature setting of the temperature feedback unit T01 9, the water mixing module 4, the heat exchange module C5 and the liquid circulation device A2 constitutes a thermal power recovery PID closed-loop control loop.

[0045] ① Liquid circulation device A2 provides the internal circulation water power source for the heat recovery and heat exchange part.

[0046] ② The water mixing module 4 serves as the main control valve for adjusting the heat recovery power. The valve body functions to divide the circulating water into two controllable circulating water streams through the adjustable opening ratio in the valve, and exchanges heat between the required water stream and the heat exchange module C5 to collect controllable thermal power. The circulating water after heat exchange is mixed with the other circulating water without heat recovery after the valve to supply heat for heat recovery and heat exchange part consumption.

[0047] In this embodiment, the high-power heating module 1 performs grouping processing of the high-power heating module based on experimental data experience, so that the heating modules of the hundred-kilowatt level in the common scheme are grouped to form a group of 50-kilowatt low-power actuators. The upper computer control system 12 selects groups for heating according to the gas volume and temperature rise value, so that the electric power impact can be reduced, and reasonable adjustments can be made according to the timeliness required by the user and the power supply capacity in the factory during equipment debugging.

[0048] The power consumption reduction of this embodiment is also reflected in the power consumption during the cooling process of the high-power test bench. Specifically, the heat generated by the fuel cell stack in the circulating water circuit of the conventional test bench needs to be exchanged by the heat exchange module B8 and then dissipated by a high-power chiller or cooling tower. In this embodiment, humidification and heating are performed through heat recovery, which not only reduces the electricity demand for humidification, but also reduces the power of the cooling water system.

[0049] The implementation scheme for reducing humidity in this embodiment is that the cooling process refers to the temperature point of the control being reduced during the gas supply and humidification process, that is, the incoming gas still needs to be humidified and heated, but the temperature inside the tank needs to be reduced. At this time, the high-power heater is completely turned off, and while the heat recovery reduces the recovery amount, the switch valve A13 is opened, and the heat exchange module A3 performs cold and heat exchange to reduce the temperature. The temperature control and heat exchange of the fuel cell is partially realized by performing cold and heat exchange through the heat exchange module B8, and the switch valve B14 is opened to control the temperature inside the fuel cell system. Example 2

[0050] like Figure 3-4 As shown in the figure, the heating power distribution diagram without heat recovery and with heat recovery during the conventional test bench test is obviously different in terms of heating power activation frequency and heating energy consumption.

[0051] When heat recovery is not enabled, the power of high-power heating module 1 is about 100KW for instantaneous heating. This heating mode has a great impact on the power system. The power supply capacity of a general factory is within a certain current limit, such as 300A, 500A. When the instantaneous power consumption exceeds the limit, it will exceed the fuse or current limit at the upper end of the power supply system, causing a trip and power outage. More seriously, it will impact the upper transformer and cause a power outage in the area. During the test process, the high-power test bench needs to humidify the atmospheric volume. In order to ensure the humidification effect and response time, the heating power will be very large. Figure 3 The pulse power is about 140KW. If the test plant uses large equipment such as air conditioners, air compressors, and chillers at the same time, the power consumption is likely to exceed 300KW, and the instantaneous current will exceed the limit, causing danger.

[0052] After enabling heat recovery, under the same loading mode and humidity conditions, the equipment's power consumption is very small, and the instantaneous power of grouped post-heating is also very small.

[0053] The above-described embodiments are only preferred embodiments of the present invention, but not all feasible embodiments of the present invention. For those skilled in the art, any obvious changes made thereto without departing from the principles and spirit of the present invention should be considered to be included in the scope of protection of the claims of the present invention.

Claims

1. A fuel cell test platform power consumption reduction control system, characterized in that: The invention comprises a heat recovery heat exchange part and a temperature control heat exchange implementation part. The high-power heating module (1) of the heat recovery heat exchange part is respectively connected to a water mixing module (4) and a liquid circulation device A (2). The liquid circulation device A (2) is connected to a heat exchange module A (3). The heat exchange module A (3) is connected to a cold water unit A and a switch valve A (13) and is connected to the water mixing module (4). The water mixing module (4) of the temperature control heat exchange implementation part is connected to a heat exchange module C (5). The heat exchange module C (5) is connected to a circulating liquid container (6). The circulating liquid container (6) The liquid circulation device B (7) is connected, the liquid circulation device B (7) is connected to the heat exchange module B (8), and the heat exchange module B (8) is connected to the fuel cell stack under test; the upper computer control system (12) is connected in series with the lower computer control system (15), and the upper computer control system (12) is respectively connected to the high-power heating module (1), the liquid circulation device A (2), the heat exchange module A (3), the water mixing module (4), the heat exchange module C (5), the circulating liquid container (6), the liquid circulation device B (7), and the heat exchange module B (8).

2. The fuel cell test platform power consumption reduction control system according to claim 1, characterized in that: The switch valve A (13) controls the heat exchange module A (3) to perform cold-heat exchange, and the switch valve B (14) controls the heat exchange module B (8) to perform cold-heat exchange.

3. The fuel cell test platform power consumption reduction control system according to claim 1, characterized in that: A temperature feedback unit T01 (9) is provided between the lower computer control system (15) and the high-power heating module (1).

4. The fuel cell test platform power consumption reduction control system according to claim 1, characterized in that: The heat recovery and heat exchange part determines whether to perform heat recovery based on the difference between the temperature feedback unit T02 (10) and the temperature feedback unit T03 (11), and controls the opening of the water mixing module (4) according to the algorithm to perform the cold and heat exchange ratio to achieve heat recovery. When the temperature cannot be increased through heat recovery or there is no heat to be recovered, the upper computer control system (12) executes the lower computer control system (15) to use the high-power heating module (1) for heating.

5. The fuel cell test platform power consumption reduction control system according to claim 4, characterized in that: When the difference between the temperature feedback unit T02 (10) and the temperature feedback unit T03 (11) exceeds 2°C, the liquid circulation device A (2) is started.

6. The fuel cell test platform power consumption reduction control system according to claim 4, characterized in that: The algorithm is PID control algorithm.

7. The fuel cell test platform power consumption reduction control system according to claim 6, characterized in that: A thermal power recovery PID closed-loop control loop is formed by setting the expected temperatures of the temperature feedback unit T01 (9), the water mixing module (4), the heat exchange module C (5) and the liquid circulation device A (2).

8. The control method of the fuel cell test platform power consumption reduction control system according to claim 1, characterized in that: The power consumption reduction control system of the fuel cell test platform controls the power of the liquid circulation device A (2), circulates the circulating liquid in the circulating liquid container (6), and reaches the set value of the temperature feedback unit T03 (11) by controlling the switch valve B (14) of the heat exchange module B (8). When the difference between the temperature feedback unit T02 (10) and the temperature feedback unit T03 (11) exceeds the set value, the liquid circulation device A (2) is started, and the circulating liquid in the high-power heating module (1) enters the heat exchange module A (3) and the mixing valve flows back to the high-power heating module (1). module (1), the temperature feedback unit T01 (9) on the high-power heating module (1) provides real-time feedback, and the lower computer control system (15) adjusts the heating power and frequency according to the difference between the demand value and the feedback value; when the high-power heating module (1) needs to be cooled, the temperature controller of the lower computer control system (15) does not work, and the upper computer control system (12) starts the cooling logic, reduces the opening of the hot water side of the mixing water module (4), increases the opening at the heat exchange module A (3), and opens the switch valve A (13), thereby achieving rapid cooling.

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