A thermostat control method, system, fuel cell, and storage medium

Abstract

The present application relates to the technical field of fuel cell, in particular to a thermostat control method, system, fuel cell and storage medium, the method comprises judging whether the water temperature of fuel cell reaches preset temperature, if not, closing the thermostat, if yes, obtaining the time of expected inlet exceeding target temperature and the difference between inlet temperature and inlet target value according to the heat production power of fuel cell and the change rate of inlet temperature, and the thermostat is adjusted according to the time of expected inlet exceeding target temperature and the difference between inlet temperature and inlet target value, through the mixing process of large and small circulation loops, when the inlet temperature approaches the target value, the inlet temperature is controlled by adjusting the thermostat, so that the system inlet temperature is not over temperature, the fuel cell can continue to run, and the mixing process is stable; automatically adapt to the adjustment speed, reduce the temperature fluctuation amplitude, the temperature control is more gentle, the temperature is stable and fast, the adjustment range of the thermostat is reduced, and the service life is prolonged.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, and more specifically to a thermostat control method, system, fuel cell, and storage medium. Background Technology

[0002] In order to reduce environmental pollution and alleviate energy pressure, a wave of research on new energy vehicles has swept the world since the last century. Currently, the mainstream types are battery-powered pure electric vehicles, hybrid electric vehicles, and fuel cell vehicles.

[0003] Hydrogen fuel cells typically consist of a proton exchange membrane and dual electrodes. They are devices that produce water and electricity through the reaction of hydrogen and oxygen. The reaction process does not involve intermediate devices, resulting in high energy efficiency. Furthermore, the only reaction product is water, which does not pollute the environment, making them truly pollution-free and zero-emission vehicles. Proton exchange membrane fuel cells are the ideal energy source for future automobiles.

[0004] Fuel cell engines require a suitable operating temperature; excessively high or low temperatures can negatively impact engine efficiency and lifespan. To ensure the fuel cell reaches its optimal operating temperature as quickly as possible and achieves best performance, the cooling system needs to be designed as a switchable large and small circulation system. This allows for rapid temperature rise when the fuel cell is low and cooling through an external heat dissipation system when the temperature is high.

[0005] When the temperature is low, in order to ensure that the fuel cell can start up quickly at low temperatures, it is necessary to adjust to a small circulation mode through the thermostat;

[0006] Once the fuel cell reaches its optimal temperature, the thermostat angle is adjusted to mix the coolant in the main circulation loop with the coolant in the secondary circulation loop for cooling.

[0007] When the final large-cycle temperature matches the small-cycle temperature, the thermostat opens fully, and the cooling system controls the coolant temperature to ensure the stability of the fuel cell's operating temperature.

[0008] In existing technologies, the thermostat does not have a temperature sensor at the front end and can only be controlled by the inlet temperature of the fuel cell stack. If the adjustment speed is slow, the system is prone to overheating, large fluctuations, and oscillations that are difficult to converge. If the adjustment speed is fast, the thermostat is prone to shutting down, resulting in large flow changes, uneven temperature distribution, and seriously affecting the thermostat's lifespan. Due to the differences in the flow resistance of the pipelines in the whole vehicle, the thermostat adjustment parameters of different models are inconsistent and difficult to be compatible. Summary of the Invention

[0009] The technical problem to be solved by this invention is to provide a thermostat control method, system, fuel cell, and storage medium that calculates the rate of temperature increase based on the difference between the fuel cell inlet temperature and the target value of the fuel cell inlet, predicts the input parameters required for the fuel cell temperature to exceed the target value based on the response time of the temperature increase under different power levels of the system, and controls the thermostat opening degree based on the predicted parameters.

[0010] To solve the above-mentioned technical problems, the first technical solution adopted by the present invention is as follows:

[0011] A thermostat control method, including

[0012] The thermostat is adjusted based on whether the fuel cell water temperature has reached the preset temperature. If not, the thermostat is closed. If so, the expected time for the inlet temperature to exceed the target temperature and the difference between the inlet temperature and the target inlet temperature are obtained based on the fuel cell's heat output and the rate of change of the inlet temperature.

[0013] Preferably, if the expected inlet temperature is greater than the target temperature for more than a preset value, the response adjustment speed parameter of the thermostat is reduced; if the expected inlet temperature is less than the target temperature for more than a preset value, the response adjustment speed parameter of the thermostat is increased.

[0014] Preferably, the thermostat is adjusted in conjunction with the response adjustment speed parameter and the difference between the inlet temperature and the inlet target value.

[0015] To solve the above-mentioned technical problems, the second technical solution adopted by the present invention is as follows:

[0016] A thermostat control system, including

[0017] The thermostat is adjusted to determine whether the fuel cell water temperature has reached the preset temperature. If not, the thermostat is turned off. If so, the expected time for the inlet temperature to exceed the target temperature and the difference between the inlet temperature and the target inlet temperature are obtained based on the fuel cell's heat output and the rate of change of the inlet temperature. The thermostat is then adjusted using PI control based on the expected time for the inlet temperature to exceed the target temperature and the difference between the inlet temperature and the target inlet temperature.

[0018] Preferably, if the expected inlet temperature is greater than the target temperature for more than a preset value, the PI response adjustment speed parameter is lowered; if the expected inlet temperature is less than the target temperature for more than a preset value, the PI response adjustment speed parameter is raised.

[0019] Preferably, the thermostat is adjusted based on the PI response adjustment speed parameter and the difference between the inlet temperature and the inlet target value.

[0020] To solve the above-mentioned technical problems, the third technical solution adopted by the present invention is as follows:

[0021] A fuel cell includes a PI controller, a stack, and a cooling system connected to the stack. The cooling system includes a large cooling loop, a small cooling loop, and a thermostat that controls the mixing of the large and small cooling loops. The PI controller controls the thermostat by performing the above-described thermostat control method.

[0022] Preferably, if the expected inlet temperature is greater than the target temperature for more than a preset value, the PI response adjustment speed parameter is lowered; if the expected inlet temperature is less than the target temperature for more than a preset value, the PI response adjustment speed parameter is raised.

[0023] Preferably, the PI controller adjusts the angle of the thermostat based on the PI response adjustment speed parameter and the difference between the inlet temperature and the inlet target value.

[0024] To solve the above-mentioned technical problems, the fourth technical solution adopted by the present invention is as follows:

[0025] A computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the above-described thermostat control method.

[0026] The beneficial effects of this invention are as follows: During the mixing process of the large and small circulation loops, when the thermostat adjusts the inlet water temperature of the fuel cell stack, it controls the inlet temperature when the inlet temperature approaches the target value, ensuring that the system inlet temperature does not exceed the limit. If the expected inlet temperature is higher than the target temperature for more than a preset value, the response adjustment speed parameter of the thermostat is reduced; if the expected inlet temperature is lower than the target temperature for more than a preset value, the response adjustment speed parameter of the thermostat is increased. This method ensures that the inlet water temperature does not exceed the limit, allowing the fuel cell to continue operating stably through the mixing process. It can automatically adapt the adjustment speed, reduce temperature fluctuations, provide smoother temperature control, achieve rapid temperature stabilization, reduce the adjustment range of the thermostat, and extend its service life. Attached Figure Description

[0027] Figure 1 This is a flowchart illustrating a thermostat control method according to a specific embodiment of the present invention. Detailed Implementation

[0028] To explain in detail the technical content, objectives, and effects of the present invention, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0029] Example 1

[0030] Reference Figure 1 A thermostat control method, including

[0031] S1. Determine if the water temperature has reached the preset temperature. If not, proceed to S8.

[0032] S2. After the preset temperature is reached, calculate the rate of change of the actual inlet temperature;

[0033] S3. Calculate the heat output power of the fuel cell;

[0034] S4. Based on the heat generation and the actual rate of change of the inlet temperature, predict the time required for the inlet temperature to exceed the preset temperature.

[0035] S5. Calculate the adjustment rate of the PI parameter based on the predicted time before the target temperature is exceeded:

[0036] If the over-temperature time is long, the PI parameter should be lowered for slow adjustment; if the over-temperature time is short, the PI parameter should be raised for rapid response adjustment.

[0037] S6. Calculate the difference between the actual inlet temperature and the target inlet temperature;

[0038] S7. Using the PI parameters obtained in 4 and the temperature difference obtained in 5, perform PI calculation and adjust the angle of the thermostat.

[0039] S8. When the water temperature is lower than the preset temperature, the thermostat will be turned off.

[0040] Example 2

[0041] A thermostat control system, including

[0042] The thermostat is adjusted to determine whether the fuel cell water temperature has reached the preset temperature. If not, the thermostat is turned off. If so, the expected time for the inlet temperature to exceed the target temperature and the difference between the inlet temperature and the target inlet temperature are obtained based on the fuel cell's heat output and the rate of change of the inlet temperature. The thermostat is then adjusted using PI control based on the expected time for the inlet temperature to exceed the target temperature and the difference between the inlet temperature and the target inlet temperature.

[0043] If the expected inlet temperature exceeds the target temperature for a longer period than a preset value, the PI response adjustment speed parameter is lowered; if the expected inlet temperature falls below the target temperature for a longer period than a preset value, the PI response adjustment speed parameter is raised. The thermostat adjusts based on the PI response adjustment speed parameter and the difference between the inlet temperature and the target inlet temperature.

[0044] Example 3

[0045] A fuel cell includes a PI controller, a stack, and a cooling system connected to the stack. The cooling system includes a large cooling loop, a small cooling loop, and a thermostat that controls the mixing of the large and small cooling loops. The PI controller controls the thermostat by executing the thermostat control method described in Embodiment 1.

[0046] If the expected inlet temperature exceeds the target temperature for more than a preset time, the PI response adjustment speed parameter is lowered; if the expected inlet temperature falls below the target temperature for more than a preset time, the PI response adjustment speed parameter is raised. The PI controller adjusts the angle of the thermostat based on the PI response adjustment speed parameter and the difference between the inlet temperature and the target inlet temperature.

[0047] Example 4

[0048] A computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the thermostat control method described in Embodiment 1.

[0049] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A thermostat control method, characterized in that, S1, judging whether the water temperature reaches the preset temperature, if not, entering S8; S2, after reaching the preset temperature, calculating the change rate of the actual inlet temperature; S3, calculating the heat generation power of the fuel cell; S4, according to the heat generation and the change rate of the actual inlet temperature, predicting the time required for the inlet temperature to exceed the preset temperature; S5, according to the predicted time when the target temperature is about to be exceeded, calculating the adjustment speed of the PI parameter: if the time when the preset temperature is exceeded is long, the PI parameter is adjusted downward for slow adjustment, if the time when the preset temperature is exceeded is short, the PI parameter is adjusted upward for fast response adjustment; S6, calculating the difference between the actual inlet temperature and the target inlet temperature; S7, performing PI calculation by using the PI parameter obtained from S5 and the temperature difference obtained from S6 to adjust the angle of the thermostat; S8, when the water temperature is lower than the preset temperature, closing the thermostat.

2. A fuel cell characterized by A PI controller, a stack and a cooling system connected to the stack, the cooling system comprising a large circulation loop, a small cooling circulation loop and a thermostat for mixing the large circulation loop and the small cooling circulation loop, the PI controller performing the thermostat control method of claim 1 to control the thermostat.

3. A computer-readable storage medium having stored thereon a computer program, characterized in that, The program is executed by the processor to realize the thermostat control method of claim 1.

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