A low temperature cold start test device for fuel cell

Abstract

The present invention provides a low-temperature cold start test device for a fuel cell, which belongs to the technical field of low-temperature test of fuel cells, and solves the problem that the refrigeration effect of the prior art fuel cell is not ideal and the cost is too high when performing low-temperature tests. The device includes an environmental chamber; the environment chamber is provided with a test stack, an air compressor, a hydrogen spray device, a boost DC-DC device, and a water pump 1, and the outside is provided with a plate heat exchanger, a three-way valve, a refrigerator, a cooling tower and a controller; the air inlet of the stack is respectively connected to the air compressor and the hydrogen spray device, the output end is connected to the input end of the controller through the boost DC-DC device, and the coolant outlet is connected to the coolant inlet through the water pump 1 and the plate heat exchanger in turn; the left side of the plate heat exchanger is connected to the port 1 of the three-way valve 1, and the right side is connected to the port 1 of the three-way valve 2; the ports 2 and 3 of the three-way valve 1 are respectively connected to the three-way valve 2 through the refrigerator and the cooling tower; the controller controls the three-way valves 1, 2, the refrigerator, and the plate radiator. A hybrid cooling control strategy is realized.

Description

Technical Field

[0001] The invention relates to the technical field of low-temperature testing of fuel cells, and in particular to a low-temperature cold start testing device for fuel cells. Background Art

[0002] Fuel cell stacks generate a lot of heat while generating electricity. At present, the power demand of fuel cell systems is getting higher and higher, and the heat dissipated has reached more than 120 kW. When the fuel cell system is doing a cold start test, the power required by the environmental chamber is also increasing. In order to save test costs, the heat can be distributed outside the cabin in the form of water cooling or air cooling.

[0003] At present, a water cooling system is used and a plate radiator is used for temperature control. When performing low-temperature tests, the coolant on both sides of the plate exchanger needs to ensure that the freezing point is lower than the test temperature, otherwise the pipeline will be blocked due to ice formation. If a low-freezing-point coolant is used on both sides of the plate exchanger, the cost is very expensive. The low-temperature cold start test platform for hydrogen fuel cell engines disclosed in CN 213425026 U uses a cooling tower to directly cool down. For laboratories, it is necessary to buy a separate low-temperature cooling tower, which is costly and requires a large experimental site. The rapid cooling device for low-temperature tests of fuel cells disclosed in CN 210296515 U uses two water tanks to achieve rapid cooling, but it is impossible to achieve temperature control during operation at the same time, and there is no mention of matching with the environmental chamber. The high and low temperature start test system for fuel cells disclosed in CN210296515 U uses an air-cooled radiator, which requires a high refrigeration capacity for the environmental chamber. Summary of the invention

[0004] The embodiment of the present invention aims to provide a low-temperature cold start test device for a fuel cell, so as to solve the problem that the refrigeration effect is not ideal and the cost is too high when the fuel cell is subjected to a low-temperature test in the prior art.

[0005] On the one hand, an embodiment of the present invention provides a low-temperature cold start test device for a fuel cell, characterized in that it includes an environmental chamber; the environmental chamber is a hollow structure, and a fuel cell stack to be tested, an air compressor, a hydrogen injection device, a boost DC-DC device, and a water pump are arranged inside, and a plate heat exchanger, two three-way valves, a refrigerator, a cooling tower, and a controller are arranged outside; wherein,

[0006] The air inlet of the fuel cell stack to be tested is connected to the air compressor, the hydrogen inlet is connected to the hydrogen injection device, and its output end is connected to the input end of the controller via the boost DC-DC device; the coolant output end of the stack is connected to its coolant input end via the water pump 1 and the plate heat exchanger in sequence;

[0007] The left side of the plate heat exchanger is connected to port 1 of three-way valve 1, and the right side is connected to port 1 of three-way valve 2; port 2 of three-way valve 1 is connected to port 2 of three-way valve 2 via a refrigerator, and port 3 is connected to port 3 of three-way valve 2 via a cooling water tower; the output end of the controller is respectively connected to the control ends of three-way valves 1 and 2, the refrigerator, and the plate radiator.

[0008] The beneficial effects of the above technical solution are as follows: there is no need to replace all the liquids circulating in the cooling tower with low-freezing-point antifreeze, which reduces costs; the control strategy when mixing large and small cycles can be verified, and the temperature can be quickly reduced after the cold start, shortening the soaking time. The plate radiator can be used to remove the waste heat generated by the fuel cell system to avoid dissipating the waste heat in the environmental chamber, which will increase the power demand of the environmental chamber and increase the equipment cost, thereby reducing the equipment cost of the environmental chamber itself. At the same time, the plate radiator is placed outside the environmental chamber, and the sensors related to the coolant need to be used in a sub-zero environment, which can reduce the cost of the plate radiator.

[0009] Based on the further improvement of the above device, a water tank for providing coolant for the fuel cell stack is further provided inside the environmental chamber; the water tank is filled with a preset dose of water, and a compensation water tank and a deionization tank are arranged on the outer wall;

[0010] The water inlet of the water tank is connected to the output end of the plate radiator via the compensation water tank and the deionization tank in sequence, and the water outlet is connected to the coolant output end of the battery stack.

[0011] The beneficial effect of the above further improvement scheme is: the water tank is arranged in the environmental chamber, and the temperature difference between the water tank and the low-temperature environment is utilized to achieve rapid cooling.

[0012] Furthermore, a compressor unit and a condenser are also provided inside the environmental chamber;

[0013] The condenser 1 is used to cool the environmental chamber, and its input end is connected to the output end of the compressor unit.

[0014] The beneficial effect of the above further improvement scheme is that the temperature control of the environmental chamber body is achieved by setting up a compressor unit and a condenser.

[0015] Furthermore, the refrigerator further comprises a refrigerant water tank, a refrigeration water pump, and a condenser 2; wherein,

[0016] The input end of the refrigeration water pump is respectively connected to the output end of the refrigerant water tank and the port two of the three-way valve one, and its output end is respectively connected to the input end of the refrigerant water tank and the water inlet of the condenser two; the air inlet of the condenser two is connected to the output end of the environmental chamber compressor unit, and the output end is connected to the port two of the three-way valve two.

[0017] The beneficial effect of the above further improvement scheme is that the cooling capacity of the environmental chamber compressor unit can be used to quickly cool the coolant on the outer cold side of the plate radiator, and the freezing point of the coolant in the entire cooling tower does not need to reach a very low freezing point, which effectively reduces the cost of the coolant.

[0018] Furthermore, a water pump 2 is provided outside the environmental chamber; wherein,

[0019] The input end of the water pump 2 is connected to the output end of the cooling tower, the output end is connected to the port 3 of the three-way valve 2, and the control end is connected to the output end of the controller.

[0020] The beneficial effect of the above further improvement scheme is that by providing a second water pump, the waste heat generated by the fuel cell system can be quickly dissipated by using a cooling tower.

[0021] Further, the controller includes:

[0022] Data acquisition unit, used to obtain the ambient temperature of the fuel cell stack to be tested T 1 , Coolant water temperature at the stack inlet T 2 , output current of the battery stack I , and the liquid level in the water tank L , sent to the data processing and control unit;

[0023] The data processing and control unit is used to preset the time before the low temperature test starts, control the three-way valves 1 and 2 to close, start the compressor unit of the environmental chamber to cool the environmental chamber until the ambient temperature reaches T 1 Reduce to the target temperature for vehicle operation in winter; at the beginning of the low-temperature test, control the fuel cell to start until the output current of the stack I When the preset value is reached, the opening of the three-way valves 1 and 2 is controlled to open the coolant transmission channel on the cooling tower side, the refrigerator is controlled to be closed, the fuel cell is cooled by the cooling tower, and the liquid level in the water tank is monitored in real time. L Once the L Below the threshold, the compensation water tank is controlled to open until L After the cold start experiment is over, the opening of three-way valves 1 and 2 is controlled to make the coolant transmission channel on the refrigerator side conductive, start the refrigerator, and cool the fuel cell and the liquid in the water tank through the environmental chamber compressor unit until the coolant water temperature at the inlet of the fuel cell stack is T 2 Lower the vehicle's operating temperature to the target temperature for winter, close three-way valves 1 and 2, and the fuel cell;

[0024] The execution unit is used to move the fuel cell to be tested, start the refrigerator and the plate radiator, and adjust the opening of the first and second three-way valves according to the control of the data processing and control unit.

[0025] The beneficial effects of the above further improved solution are: the structure and function of the controller are limited. Before low-temperature startup, the temperature of the fuel cell system can be consistent with the target temperature, and rapid cooling can be achieved.

[0026] Furthermore, the data acquisition unit further comprises:

[0027] Temperature sensor 1 is installed on the lower inner wall of the water tank to collect the temperature of the liquid in the water tank in real time as the ambient temperature. T 1 ;

[0028] Temperature sensor 2 is installed on the inner wall of the water coolant input pipe of the fuel cell stack to collect the coolant water temperature at the fuel cell stack inlet in real time. T 2 ;

[0029] Temperature sensor 3 is installed on the coolant outlet pipe of the plate radiator to collect the coolant temperature output by the plate radiator. T 3 ;

[0030] The liquid level sensor is installed on the inner wall of the water tank. Its output end is connected to the input end of the controller to measure the liquid level in the water tank. L ;

[0031] The current sensor is set at the output end of the boost DC-DC device to collect the output current of the battery stack in real time. I .

[0032] The beneficial effect of the above further improvement scheme is that the various data collected by the above data acquisition unit ensure the normal operation of the fuel cell system and lay the foundation for the precise control of the low-temperature cold start test of the fuel cell.

[0033] Furthermore, the execution unit further comprises:

[0034] A robot arm is arranged at one side of the fuel cell stack to be tested, and is used to move the fuel cell stack to be tested to a designated test position or a designated standby position according to a control signal of a data processing and control unit;

[0035] MOS switch 1, whose output end is connected to the control end of three-way valve 1, is used to transmit an opening signal to the three-way valve 1 after it is turned on;

[0036] MOS switch 2, whose output end is connected to the control end of three-way valve 2, is used to transmit an opening signal to the three-way valve 2 after it is turned on;

[0037] MOS switch 3, whose output end is connected to the control end of the refrigerator, is used to control the start-up of the refrigerator;

[0038] The output end of the MOS switch 4 is connected to the control end of the plate type radiator and is used for controlling the start-up of the plate type radiator.

[0039] The beneficial effect of the above further improvement scheme is that, through the setting of the above execution unit, it is possible to avoid the need for the freezing point of the coolant in the cooling tower to be very low.

[0040] Furthermore, before the low temperature test is started, the data processing and control unit executes the following procedures:

[0041] After the fuel cell to be tested is moved to the designated test position at a preset time before the low-temperature test is started, the low-temperature cold start test device of the fuel cell is started;

[0042] Detect whether the opening of three-way valves 1 and 2 is 0, and control the corresponding three-way valves whose opening is not 0 to close;

[0043] Periodically start the compressor unit of the environmental chamber to cool the environmental chamber until the ambient temperature reaches T 1 , Coolant water temperature at the stack inlet T 2 Lower the vehicle's operating temperature to the target temperature for winter and turn off the compressor unit in the environmental chamber.

[0044] The beneficial effect of the above further improvement scheme is that the execution program of the controller is limited before the low-temperature test is started, so that the temperature of the entire fuel cell system can be consistent with the target temperature.

[0045] Further, at the beginning of the low temperature test, the data processing and control unit executes the following procedures;

[0046] Power on the fuel cell, control the air compressor and hydrogen injection equipment to start respectively, and deliver hydrogen and oxygen to the fuel cell stack;

[0047] Controlling the water pump to run at a preset speed, starting the plate radiator, and delivering coolant to the fuel cell stack;

[0048] Monitor the output current of the battery stack I Once the I When the preset value is reached, the opening of the three-way valve 1 and 2 is controlled to make the coolant transmission channel on the refrigerator side conductive;

[0049] Monitor the coolant temperature at the output of the plate radiator T3 Once the T 3 When the target temperature is reached, the refrigerator is controlled to be closed, and the opening of the first and second three-way valves is adjusted to control the refrigerator to be closed, so that the coolant transmission channel on the cooling tower side is open;

[0050] Real-time monitoring of the liquid level in the water tank L Once the L Below the threshold, the compensation water tank is controlled to open until L Close after being greater than or equal to the threshold;

[0051] After the cold start experiment is completed, the data processing and control unit executes the following procedures:

[0052] Controlling the opening of three-way valves 1 and 2 to make the coolant transmission channel on the fuel cell side conductive;

[0053] Start the environmental chamber compressor and refrigerator in sequence to cool down the fuel cell and the liquid in the water tank until the coolant water temperature at the stack inlet is T 2 Lower the vehicle's operating temperature to the target temperature for winter, close three-way valves 1 and 2, and the fuel cell;

[0054] Transfer the fuel cell stack to be tested from the designated test position to the designated backup position.

[0055] The beneficial effect of the above further improvement scheme is that the execution program of the controller during and after the low temperature test is limited respectively, so that the temperature of the entire fuel cell system can be consistent with the target temperature.

[0056] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the disclosure, nor is it intended to limit the scope of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The above and other objects, features and advantages of the present disclosure will become more apparent through a more detailed description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present disclosure.

[0058] Figure 1 A schematic structural diagram of a low-temperature cold start test device for a fuel cell according to Embodiment 1 of the present invention is shown;

[0059] Figure 2 A schematic structural diagram of a low-temperature cold start test device for a fuel cell according to Embodiment 2 of the present invention is shown.

[0060] Reference numerals:

[0061] L - Changes in liquid level; T 1 - ambient temperature; T 2 - Coolant water temperature at the stack inlet; T 3 - Coolant temperature at the plate radiator output. DETAILED DESCRIPTION

[0062] Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0063] As used herein, the term "including" and its variations mean open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "based at least in part on". The terms "an example embodiment" and "an embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc. may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0064] Example 1

[0065] One embodiment of the present invention discloses a low-temperature cold start test device for a fuel cell, including an environmental chamber. The environmental chamber is a hollow structure, and is provided with a fuel cell stack to be tested, an air compressor, a hydrogen injection device, a boost DC-DC device, and a water pump. The exterior of the chamber is provided with a plate heat exchanger, two three-way valves, a refrigerator, a cooling tower, and a controller. Figure 1 As shown, the dotted line is the internal area of ​​the environmental chamber.

[0066] In the environmental chamber, the air inlet of the fuel cell stack to be tested is connected to the air compressor, the hydrogen inlet is connected to the hydrogen injection equipment, and its output end is connected to the input end of the controller via a boost DC-DC device; the coolant output end of the stack is connected to its coolant input end via a water pump and an external plate heat exchanger in sequence.

[0067] Outside the environmental chamber, the left side of the plate heat exchanger is connected to port 1 of three-way valve 1, and the right side is connected to port 1 of three-way valve 2; port 2 of three-way valve 1 is connected to port 2 of three-way valve 2 via a refrigerator, and port 3 is connected to port 3 of three-way valve 2 via a cooling water tower; the output end of the controller is respectively connected to the control ends of three-way valves 1 and 2, the refrigerator, and the plate radiator.

[0068] Plate heat exchanger is a new type of high-efficiency heat exchanger made of a series of metal sheets with a certain corrugated shape. Thin rectangular channels are formed between various plates, and heat is exchanged through the plates. Plate heat exchanger is an ideal equipment for liquid-liquid and liquid-steam heat exchange. It has the characteristics of high heat exchange efficiency, small heat loss, compact and light structure, small footprint, easy installation and cleaning, wide application, and long service life. Under the same pressure loss, its heat transfer coefficient is 3-5 times higher than that of shell and tube heat exchanger, and the footprint is one-third of that of tube heat exchanger, and the heat recovery rate can be as high as 90% or more.

[0069] Compared with the prior art, the device provided in this embodiment does not need to replace all the liquids circulating in the cooling tower with antifreeze with a low freezing point, thereby reducing costs; the control strategy when mixing large and small cycles can be verified, and the temperature can be quickly reduced after the cold start, thereby shortening the soaking time. The plate radiator can be used to carry away the waste heat generated by the fuel cell system to avoid dissipating the waste heat in the environmental chamber, which increases the power demand of the environmental chamber and increases the equipment cost, thereby reducing the equipment cost of the environmental chamber itself. At the same time, the plate radiator is placed outside the environmental chamber, and the sensors related to the coolant need to be used in a sub-zero environment, which can reduce the cost of the plate radiator.

[0070] Example 2

[0071] Based on the optimization of Example 1, a water tank for providing coolant for the fuel cell stack is further provided inside the environmental chamber; the water tank is filled with a preset dose of water, and a compensation water tank and a deionization tank are arranged on the outer wall.

[0072] The water inlet of the water tank is connected to the output end of the plate radiator through the compensation water tank, the deionization tank, and the water outlet is connected to the coolant output end of the battery stack, such as Figure 2 shown.

[0073] Preferably, a compressor unit and a condenser 1 are also provided inside the environmental chamber. The condenser 1 is used to cool the environmental chamber, and its input end is connected to the output end of the compressor unit. The environmental chamber has its own compressor unit, which can be used for cooling inside the environmental chamber, as well as cooling the fuel cell and the water tank.

[0074] Preferably, the refrigerator further comprises a refrigerant water tank, a refrigeration water pump, and a second condenser. The input end of the refrigeration water pump is respectively connected to the output end of the refrigerant water tank and the second port of the three-way valve, and the output end thereof is respectively connected to the input end of the refrigerant water tank and the water inlet of the second condenser; the air inlet of the second condenser is connected to the output end of the environmental chamber compressor unit, and the output end is connected to the second port of the second three-way valve.

[0075] Preferably, a water pump 2 is further provided outside the environmental chamber, wherein the input end of the water pump 2 is connected to the output end of the cooling tower, the output end is connected to the port 3 of the three-way valve 2, and the control end is connected to the output end of the controller.

[0076] Preferably, the controller includes a data acquisition unit, a data processing and control unit, and an execution unit which are connected in sequence.

[0077] Data acquisition unit, used to obtain the ambient temperature of the fuel cell stack to be tested T 1 , Coolant water temperature at the stack inlet T 2 , output current of the battery stack I , and the liquid level in the water tank L , sent to the data processing and control unit.

[0078] The data processing and control unit is used to preset the time before the low temperature test starts, control the three-way valves 1 and 2 to close, and start the compressor unit of the environmental chamber to cool the environmental chamber until the ambient temperature reaches T 1 Reduce to the target temperature for vehicle operation in winter; at the beginning of the low-temperature test, control the fuel cell to start until the output current of the stack I When the preset value is reached, the opening of the three-way valves 1 and 2 is controlled to open the coolant transmission channel on the cooling tower side, the refrigerator is controlled to be closed, the fuel cell is cooled by the cooling tower, and the liquid level in the water tank is monitored in real time. L ,once L Below the threshold, the compensation water tank is controlled to open until L After the cold start experiment is over, the opening of three-way valves 1 and 2 is controlled to make the coolant transmission channel on the refrigerator side conductive, start the refrigerator, and cool the fuel cell and the liquid in the water tank through the environmental chamber compressor unit until the coolant water temperature at the inlet of the fuel cell stack is T 2 Lower the vehicle's operating temperature to the target temperature for winter, and close three-way valves one and two, as well as the fuel cell.

[0079] The execution unit is used to move the fuel cell to be tested, start the refrigerator and the plate radiator, and adjust the opening of the first and second three-way valves according to the control of the data processing and control unit.

[0080] Preferably, the data acquisition unit further includes temperature sensors 1 and 2, and a liquid level sensor.

[0081] Temperature sensor 1 is installed on the lower inner wall of the water tank to collect the temperature of the liquid in the water tank in real time as the ambient temperature. T 1 .

[0082] Temperature sensor 2 is installed on the inner wall of the water coolant input pipe of the fuel cell stack to collect the coolant water temperature at the fuel cell stack inlet in real time. T 2 .

[0083] Temperature sensor 3 is installed on the coolant outlet pipe of the plate radiator to collect the coolant temperature output by the plate radiator. T 3 .

[0084] The liquid level sensor is installed on the inner wall of the water tank. Its output end is connected to the input end of the controller to measure the liquid level in the water tank. L .

[0085] The current sensor is set at the output end of the boost DC-DC device to collect the output current of the battery stack in real time. I .

[0086] Preferably, the execution unit further includes a robot arm and MOS switch 1 to MOS switch 4.

[0087] The robot arm is arranged at one side of the fuel cell stack to be tested, and is used to move the fuel cell stack to be tested to a designated test position or a designated standby position according to a control signal of a data processing and control unit.

[0088] The MOS switch 1 has an output end connected to the control end of the three-way valve 1 and is used to transmit an opening signal to the three-way valve 1 after being turned on.

[0089] The output end of the MOS switch 2 is connected to the control end of the three-way valve 2, and is used to transmit an opening signal to the three-way valve 2 after being turned on.

[0090] The output end of the MOS switch three is connected to the control end of the refrigerator and is used to control the start-up of the refrigerator.

[0091] The output end of the MOS switch 4 is connected to the control end of the plate type radiator and is used for controlling the start-up of the plate type radiator.

[0092] Preferably, before the low temperature test is started, the data processing and control unit executes the following procedures:

[0093] S1. Before the low-temperature test is started, the fuel cell to be tested is controlled to move to the designated test position at a preset time, the target temperature of the environmental chamber is set, and the low-temperature cold start test device of the fuel cell is started (the environmental chamber is started);

[0094] S2. Detect whether the opening of three-way valves 1 and 2 is 0, and control the corresponding three-way valves whose opening is not 0 to close;

[0095] S3. Periodically start the compressor unit of the environmental chamber to cool down the environmental chamber until the ambient temperature reachesT 1 , Coolant water temperature at the stack inlet T 2 The temperature is lowered to the target temperature for the whole vehicle operation in winter, maintaining a constant temperature or shutting down the compressor unit of the environmental chamber.

[0096] Preferably, at the beginning of the low temperature test, the data processing and control unit executes the following procedure;

[0097] S4. Power on the fuel cell, control the air compressor and the hydrogen injection device to start respectively, and deliver hydrogen and oxygen to the fuel cell stack;

[0098] S5. Controlling the water pump to run at a preset speed, starting the plate radiator, and delivering coolant to the inside of the fuel cell stack;

[0099] S6. Monitor the output current of the battery stack I Once the I When the preset value is reached, the three-way valves 1 and 2 are controlled to open, and the opening degree makes the coolant transmission channel on the refrigerator side (i.e., the refrigerator-plate heat exchanger branch) conductive, the fuel cell system is temperature-controlled through the plate radiator, and the waste heat generated by the fuel cell is taken away through the refrigerator;

[0100] S7. Monitor the coolant temperature output from the plate radiator T 3 Once the T 3 When the target temperature is reached, the refrigerator is controlled to be closed, and the opening of three-way valves 1 and 2 is adjusted to open the cooling tower side coolant transmission channel (i.e., cooling tower-plate heat exchanger branch), so that the fuel cell stack is cooled through the cooling tower;

[0101] S8. Real-time monitoring of the liquid level in the water tank L Once the L Below the threshold, the compensation water tank is controlled to open until L Close after it is greater than or equal to the threshold.

[0102] Preferably, step S8 also needs to be performed before step S4, and the liquid level of the fuel cell needs to be ensured before operation after the fuel cell is filled with water and exhausted.

[0103] After the cold start experiment is completed, the data processing and control unit executes the following procedures:

[0104] S9. Control the opening of three-way valves 1 and 2 to open the coolant transmission channel (cooling water pump-condenser-plate radiator) on the fuel cell side until the coolant temperature output by the plate radiator reaches T 3 Equal to ambient temperature T 1 ;

[0105] S10. Start the environmental chamber compressor and refrigerator in sequence to cool down the fuel cell and the liquid in the water tank until the coolant water temperature at the stack inlet is T 2 and the coolant temperature output by the plate radiator T 3 All are lowered to the target temperature for vehicle operation in winter, and three-way valves 1 and 2, as well as the fuel cell, are closed;

[0106] S10. Move the fuel cell stack to be tested from the designated test location to the designated standby location.

[0107] Compared with Example 1, the device provided in this embodiment can reduce the temperature of the large cycle (i.e., the entire environmental chamber, including the cooling of the intake process and the cooling of the fuel cell stack itself) and the small cycle (the cycle of the fuel cell stack's own cooling, including the fuel cell stack-water pump-plate heat exchanger-fuel cell stack) to the required temperature before the cold start test, thereby simulating the low temperature environment in winter to the greatest extent.

[0108] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terms used herein are selected to best explain the principles of the embodiments, practical applications, or improvements over the prior art, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A low temperature cold start test device for a fuel cell, characterized in that: It includes an environmental chamber; the environmental chamber is a hollow structure, and is provided with a fuel cell stack to be tested, an air compressor, a hydrogen injection device, a boost DC-DC device, and a water pump, and is provided with a plate heat exchanger, two three-way valves, a refrigerator, a cooling tower, and a controller on the outside; wherein, The air inlet of the fuel cell stack to be tested is connected to the air compressor, the hydrogen inlet is connected to the hydrogen injection device, and its output end is connected to the input end of the controller via the boost DC-DC device; the coolant output end of the stack is connected to its coolant input end via the water pump 1 and the plate heat exchanger in sequence; The left side of the plate heat exchanger is connected to port 1 of three-way valve 1, and the right side is connected to port 1 of three-way valve 2; port 2 of three-way valve 1 is connected to port 2 of three-way valve 2 via a refrigerator, and port 3 is connected to port 3 of three-way valve 2 via a cooling water tower; the output end of the controller is respectively connected to the control ends of three-way valves 1 and 2, the refrigerator, and the plate radiator.

2. The low temperature cold start test device for a fuel cell according to claim 1, characterized in that: The interior of the environmental chamber is also provided with a water tank for providing coolant for the fuel cell stack; the water tank is filled with a preset dose of water, and a compensation water tank and a deionization tank are arranged on the outer wall; The water inlet of the water tank is connected to the output end of the plate radiator via the compensation water tank and the deionization tank in sequence, and the water outlet is connected to the coolant output end of the battery stack.

3. The low temperature cold start test device for a fuel cell according to claim 2, characterized in that: The interior of the environmental chamber is also provided with a compressor unit and a condenser; The condenser 1 is used to cool the environmental chamber, and its input end is connected to the output end of the compressor unit.

4. The low temperature cold start test device for a fuel cell according to claim 3, characterized in that: The refrigerator further includes a refrigerant water tank, a refrigeration water pump, and a condenser 2; wherein, The input end of the refrigeration water pump is respectively connected to the output end of the refrigerant water tank and the port two of the three-way valve one, and its output end is respectively connected to the input end of the refrigerant water tank and the water inlet of the condenser two; the air inlet of the condenser two is connected to the output end of the environmental chamber compressor unit, and the output end is connected to the port two of the three-way valve two.

5. The low temperature cold start test device for a fuel cell according to any one of claims 1 to 4, characterized in that: A water pump 2 is also provided outside the environmental chamber; wherein, The input end of the water pump 2 is connected to the output end of the cooling tower, the output end is connected to the port 3 of the three-way valve 2, and the control end is connected to the output end of the controller.

6. The low temperature cold start test device for a fuel cell according to any one of claims 2 to 4, characterized in that: The controller includes: Data acquisition unit, used to obtain the ambient temperature of the fuel cell stack to be tested T 1. Coolant water temperature at the stack inlet T 2. Output current of the battery stack I , and the liquid level in the water tank L , sent to the data processing and control unit; The data processing and control unit is used to preset the time before the low temperature test starts, control the three-way valves 1 and 2 to close, start the compressor unit of the environmental chamber to cool the environmental chamber until the ambient temperature reaches T 1 Reduce to the target temperature of the vehicle in winter; at the beginning of the low temperature test, control the fuel cell to start until the output current of the stack I When the preset value is reached, the opening of the three-way valves 1 and 2 is controlled to open the coolant transmission channel on the cooling tower side, the refrigerator is controlled to be closed, the fuel cell is cooled by the cooling tower, and the liquid level in the water tank is monitored in real time. L Once the L Below the threshold, the compensation water tank is controlled to open until L After the cold start experiment is over, the opening of three-way valves 1 and 2 is controlled to make the coolant transmission channel on the refrigerator side conductive, start the refrigerator, and cool the fuel cell and the liquid in the water tank through the environmental chamber compressor unit until the coolant water temperature at the inlet of the fuel cell stack is T 2. Lower the vehicle's operating temperature to the target temperature for winter, close three-way valves 1 and 2, and the fuel cell; The execution unit is used to move the fuel cell to be tested according to the control of the data processing and control unit, and start the compressor unit, the refrigerator, the plate radiator, and adjust the opening of the first and second three-way valves.

7. The low temperature cold start test device for a fuel cell according to claim 6, characterized in that: The data acquisition unit further comprises: Temperature sensor 1 is installed on the lower inner wall of the water tank to collect the temperature of the liquid in the water tank in real time as the ambient temperature. T 1; Temperature sensor 2 is installed on the inner wall of the water coolant input pipe of the fuel cell stack to collect the coolant water temperature at the entrance of the fuel cell stack in real time. T 2; Temperature sensor 3 is installed on the coolant outlet pipe of the plate radiator to collect the coolant temperature output by the plate radiator. T 3; The liquid level sensor is installed on the inner wall of the water tank. Its output end is connected to the input end of the controller to measure the liquid level in the water tank. L ; The current sensor is set at the output end of the boost DC-DC device to collect the output current of the battery stack in real time. I .

8. The low temperature cold start test device for a fuel cell according to claim 7, characterized in that: The execution unit further comprises: A robot arm is arranged at one side of the fuel cell stack to be tested, and is used to move the fuel cell stack to be tested to a designated test position or a designated standby position according to a control signal of a data processing and control unit; MOS switch 1, whose output end is connected to the control end of three-way valve 1, is used to transmit an opening signal to the three-way valve 1 after it is turned on; MOS switch 2, whose output end is connected to the control end of three-way valve 2, is used to transmit an opening signal to the three-way valve 2 after it is turned on; MOS switch 3, whose output end is connected to the control end of the refrigerator, is used to control the start-up of the refrigerator; The output end of the MOS switch 4 is connected to the control end of the plate type radiator and is used for controlling the start-up of the plate type radiator.

9. The low temperature cold start test device for a fuel cell according to claim 7 or 8, characterized in that: Before the low temperature test is started, the data processing and control unit executes the following procedures: After the fuel cell to be tested is moved to the designated test position at a preset time before the low-temperature test is started, the low-temperature cold start test device of the fuel cell is started; Detect whether the opening of three-way valves 1 and 2 is 0, and control the corresponding three-way valves whose opening is not 0 to close; Periodically start the compressor unit of the environmental chamber to cool the environmental chamber until the ambient temperature reaches T 1. Coolant water temperature at the stack inlet T 2. Reduce the temperature to the target temperature for vehicle operation in winter and turn off the compressor unit of the environmental chamber.

10. The low temperature cold start test device for a fuel cell according to claim 9, characterized in that: At the beginning of the low temperature test, the data processing and control unit executes the following procedures: Power on the fuel cell, control the air compressor and hydrogen injection equipment to start respectively, and deliver hydrogen and oxygen to the fuel cell stack; Controlling the water pump to run at a preset speed, starting the plate radiator, and delivering coolant to the fuel cell stack; Monitor the output current of the battery stack I Once the I When the preset value is reached, the opening of the three-way valves 1 and 2 is controlled to make the coolant transmission channel on the refrigerator side conductive; Monitor the coolant temperature at the output of the plate radiator T 3. Once the T 3. When the target temperature is reached, the refrigerator is controlled to be turned off, and the opening of the three-way valves 1 and 2 is adjusted to make the coolant transmission channel on the cooling tower side conductive; Real-time monitoring of the liquid level in the water tank L Once the L Below the threshold, the compensation water tank is controlled to open until L Close after being greater than or equal to the threshold; After the cold start experiment is completed, the data processing and control unit executes the following procedures: Control the opening of three-way valves 1 and 2 to make the coolant transmission channel on the fuel cell side conductive until the coolant temperature output by the plate radiator reaches T 3 is equal to the ambient temperature T 1; Start the environmental chamber compressor and refrigerator in sequence to cool down the fuel cell and the liquid in the water tank until the coolant water temperature at the stack inlet is T 2. Lower the vehicle's operating temperature to the target temperature for winter, close three-way valves 1 and 2, and the fuel cell; Transfer the fuel cell stack to be tested from the designated test position to the designated backup position.

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