A fuel cell engine stack water field static pressure elimination system and method

Abstract

The present application relates to a kind of fuel cell engine stack water field static pressure elimination system and method, including purging mechanism;Fuel cell unit, which includes fuel cell engine, and water pump connected with the fuel cell engine, the fuel cell engine is provided with purging air inlet, cooling liquid inlet and cooling liquid outlet, the purging mechanism is connected with purging air inlet;Heat dissipation unit is connected with the fuel cell engine by the cooling liquid inlet and cooling liquid outlet;Pressure relief unit, including ball valve assembly and pressure relief tank, the ball valve assembly includes first ball valve, second ball valve and third ball valve, the first ball valve is arranged between heat dissipation unit and water pump inlet, the second ball valve is arranged between cooling liquid outlet and heat dissipation unit.The present application can realize when fuel cell engine stops, the quick elimination to fuel stack water field static pressure, to effectively improve engine performance, increase the life of engine.

Description

Technical Field

[0001] This invention relates to the field of static pressure elimination technology in fuel cell stack water field, and in particular to a system and method for eliminating static pressure in the water field of a fuel cell engine stack. Background Technology

[0002] Hydrogen fuel has advantages such as being pollution-free, highly efficient, and recyclable, making it the future direction of new energy fuel development and the main power source for fuel cell vehicles. The working principle of a fuel cell vehicle is that hydrogen and air, as fuel, undergo a chemical reaction in the fuel cell stack to generate electricity, which drives the electric motor. The electric motor then drives the mechanical transmission structure in the vehicle, which in turn drives the front or rear axle and other walking mechanisms, thus propelling the fuel cell vehicle forward.

[0003] However, when the fuel cell engine is shut down, the static pressure of the fuel cell engine stack water field coolant causes the coolant to slowly seep through the graphite bipolar plate to the fuel cell membrane electrode side, contaminating the fuel cell membrane electrode and causing a decrease in engine performance and a shortened lifespan. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a static pressure elimination system and method for the water field of a fuel cell engine stack, which can quickly eliminate the static pressure in the water field of the fuel cell engine stack after the fuel cell engine is shut down, thereby effectively improving engine performance and increasing engine life.

[0005] To address the aforementioned technical problems, this invention provides a hydrostatic pressure elimination system for a fuel cell engine stack water field, comprising:

[0006] Purging mechanism;

[0007] A fuel cell unit includes a fuel cell engine and a water pump connected to the fuel cell engine. The fuel cell engine has a purge inlet, a coolant inlet, and a coolant outlet. The purge mechanism is connected to the purge inlet. The fuel cell unit also includes a monitoring unit for monitoring the water pressure and air pressure of the engine.

[0008] A heat dissipation unit is connected to the fuel cell engine through the coolant inlet and coolant outlet;

[0009] The pressure relief unit includes a ball valve assembly and a pressure relief box. The ball valve assembly includes a first ball valve, a second ball valve, and a third ball valve. The first ball valve is disposed between the heat dissipation unit and the water pump inlet. The second ball valve is disposed between the coolant outlet and the heat dissipation unit. The purging mechanism is connected to the water pump inlet through the pressure relief box and the third ball valve. The third ball valve is disposed between the water pump inlet and the purging mechanism.

[0010] Preferably, the pressure relief box is provided with an elastic element, which is movably connected to the inner wall of the pressure relief box, and the elastic element moves along the pressure direction.

[0011] Preferably, the elastic element is an elastic film or a piston.

[0012] Preferably, the heat dissipation unit includes a main radiator and an expansion tank connected to each other, the liquid outlet of the main radiator is connected to a first ball valve, and the liquid inlet of the main radiator is connected to a second ball valve.

[0013] Preferably, the monitoring unit includes a first temperature and pressure sensor and a temperature and humidity pressure sensor, wherein the first temperature and pressure sensor is disposed at the coolant inlet and the temperature and humidity pressure sensor is disposed at the air inlet of the fuel cell engine.

[0014] Preferably, the purging mechanism includes an air compressor and an intercooler arranged sequentially along the air intake direction, the intercooler outlet is connected to the purging air inlet, and the intercooler outlet is also connected to the pressure relief box.

[0015] This invention also provides a method for eliminating static pressure in the water field of a fuel cell engine stack. The method employs the static pressure elimination system described above to eliminate static pressure in the water field of the fuel cell engine stack. The method includes...

[0016] Step S1: The fuel cell engine is shut down, and the connection between the fuel cell engine and the heat dissipation unit is disconnected;

[0017] Step S2: Connect the fuel cell engine and the pressure relief box to release the static pressure of the fuel cell engine stack water field;

[0018] Step S3: Collect the pressure value of the water field of the fuel cell engine and determine whether the pressure value is zero;

[0019] Step S4: When the pressure value is zero, disconnect the fuel cell engine from the pressure relief box;

[0020] Step S5: Before restarting the fuel cell engine, connect the fuel cell engine and the cooling unit, and keep the connection between the fuel cell engine and the pressure relief box disconnected.

[0021] Step S6: Collect the air pressure value of the fuel cell engine and determine whether the air pressure value reaches the specified value P1. If the air pressure value reaches the specified value P1, connect the fuel cell engine and the pressure relief box to discharge the coolant in the pressure relief box.

[0022] Step S7: Disconnect the connection between the fuel cell engine and the pressure relief box.

[0023] Preferably, in step S6, the coolant in the pressure relief tank is discharged to the cooling system of the fuel cell engine and the heat dissipation unit.

[0024] Preferably, in step S2, the fuel cell engine and the pressure relief tank are connected, allowing some of the coolant to be discharged into the pressure relief tank.

[0025] Preferably, in step S4, when the pressure value is not zero, a manual inspection is performed.

[0026] The technical solution of the present invention has the following advantages compared with the prior art:

[0027] This invention discloses a static pressure relief system for the water field of a fuel cell engine stack. Based on a fuel cell unit, it includes a heat dissipation unit, a purging mechanism, and a pressure relief unit. The pressure relief unit comprises a first ball valve located between the heat dissipation unit and the water pump inlet, a second ball valve located between the coolant outlet and the heat dissipation unit, and a third ball valve and a pressure relief tank located between the purging mechanism and the water pump inlet. The system operates as follows: When the fuel cell engine stops, the first and second ball valves are closed, isolating the fuel cell engine from the heat dissipation unit and preventing coolant from flowing from the heat dissipation unit to the fuel cell engine. Then, the third ball valve is opened, releasing the static pressure in the fuel cell stack water field into the pressure relief tank via the third ball valve and pipeline. Simultaneously, some coolant is discharged into the pressure relief tank. The pressure value of the fuel cell engine stack water field is monitored by a monitoring unit. When the pressure value is zero, the third ball valve is closed, and the engine stops, effectively protecting the fuel cell membrane electrode assembly (MEA). Furthermore, before starting the fuel cell engine, the first and second ball valves are opened while the third ball valve remains closed. At this time, the fuel cell engine and the cooling unit are normally connected. After the fuel cell engine starts, the air pressure value of the fuel cell engine is monitored by the monitoring unit. When the air pressure value reaches the set pressure, the third ball valve is opened, and the gas pressure from the purging mechanism is applied to the pressure relief box, which re-pressurizes the coolant in the pressure relief box into the cooling system. Then the third ball valve is closed, and the engine runs normally. In this way, the static pressure of the fuel cell stack water field can be quickly eliminated after the fuel cell engine stops, thereby effectively improving engine performance and increasing engine life. Attached Figure Description

[0028] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein...

[0029] Figure 1 This is a schematic diagram of the structure of the preferred embodiment of the present invention.

[0030] Figure 2 This is a schematic diagram of the workflow of the preferred embodiment of the present invention.

[0031] Explanation of reference numerals in the accompanying drawings: 1. Water pump; 2. Heat dissipation unit; 21. Liquid inlet pipe; 3. Pressure relief tank; 31. Elastic element; 41. First ball valve; 42. Second ball valve; 43. Third ball valve; 5. Purge pipe; 6. Liquid outlet pipe; 71. First temperature and pressure sensor; 72. Temperature, humidity, and pressure sensor; 81. PTC heater; 82. Thermostat. Detailed Implementation

[0032] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0033] Example 1

[0034] Reference Figures 1 to 2 As shown, this invention discloses a hydrostatic pressure elimination system for a fuel cell engine stack water field, comprising,

[0035] Purging mechanism;

[0036] A fuel cell unit includes a fuel cell engine and a water pump 1 connected to the fuel cell engine. The fuel cell engine is provided with a purge air inlet, a coolant inlet and a coolant outlet. The purge mechanism is connected to the purge air inlet. The fuel cell unit also includes a monitoring unit for monitoring the water pressure and air pressure of the engine.

[0037] The heat dissipation unit 2 is connected to the fuel cell engine through the coolant inlet and coolant outlet. It should be noted that the water pump 1 is located between the coolant inlet and the heat dissipation unit 2.

[0038] The pressure relief unit includes a ball valve assembly and a pressure relief box 3. The ball valve assembly includes a first ball valve 41, a second ball valve 42, and a third ball valve 43. The first ball valve 41 is located between the heat dissipation unit 2 and the inlet of the water pump 1. The second ball valve 42 is located between the coolant outlet and the heat dissipation unit 2. The purging mechanism is connected to the inlet of the water pump 1 through the pressure relief box 3 and the third ball valve 43. The third ball valve 43 is located between the inlet of the water pump 1 and the purging mechanism. It should be noted that a first tee joint is provided between the first ball valve 41 and the inlet of the water pump 1. The third ball valve 43 and the pressure relief box 3 are located on a branch of the first tee joint. A second tee joint is provided on the purging pipe 5 of the purging mechanism. The pressure relief box 3 is also located on a branch of the second tee joint. One end of the pressure relief box 3 is connected to the purging pipe 5 of the purging mechanism, and the other end is connected to the third ball valve 43.

[0039] Therefore, it can be understood that the static pressure elimination system for the water field of a fuel cell engine stack protected by this invention is based on a fuel cell unit and includes a heat dissipation unit, a purging mechanism, and a pressure relief unit. The pressure relief unit includes a first ball valve located between the heat dissipation unit and the water pump inlet, a second ball valve located between the coolant outlet and the heat dissipation unit, and a third ball valve and a pressure relief tank located between the purging mechanism and the water pump inlet. Using the cooperation of the above structures, the system of this invention operates as follows: When the fuel cell engine stops, the first and second ball valves are closed, thereby isolating the fuel cell engine and the heat dissipation unit and preventing coolant in the heat dissipation unit from flowing into the fuel cell engine. Then, the third ball valve is opened. At this time, the static pressure of the fuel cell stack water field is released into the pressure relief tank through the third ball valve and pipeline, while some coolant is discharged. The discharged coolant enters the pressure relief tank. The pressure value of the fuel cell engine water field is monitored by a monitoring unit. When the pressure value is zero, the third ball valve is closed, the engine stops, and thus the fuel cell membrane electrode assembly is effectively protected. Furthermore, before starting the fuel cell engine, the first and second ball valves are opened while the third ball valve remains closed. At this time, the fuel cell engine and the cooling unit are normally connected. After the fuel cell engine starts, the air pressure value of the fuel cell engine is monitored by the monitoring unit. When the air pressure value reaches the set pressure, the third ball valve is opened, and the gas pressure from the purging mechanism is applied to the pressure relief box, which re-pressurizes the coolant in the pressure relief box into the cooling system. Then the third ball valve is closed, and the engine runs normally. In this way, the static pressure of the fuel cell stack water field can be quickly eliminated after the fuel cell engine stops, thereby effectively improving engine performance and increasing engine life.

[0040] Furthermore, the pressure relief box 3 is provided with an elastic element 31, which is movably connected to the inner wall of the pressure relief box. When the elastic element 31 is subjected to a force from air or liquid, the elastic element 31 can move in the direction of airflow or liquid flow.

[0041] Furthermore, the elastic element 31 is an elastic diaphragm or piston, wherein the elastic diaphragm includes a silicone pad and elastic rubber. With this configuration, when the third ball valve 43 is opened, the static pressure of the fuel cell stack water field is released into the pressure relief tank 3 via the third ball valve 43 and pipelines, while simultaneously discharging some coolant. The discharged coolant presses the elastic diaphragm or piston in the middle of the pressure relief tank 3 to one side.

[0042] In detail, the heat dissipation unit 2 includes a main radiator and an expansion tank connected to each other. The expansion tank is provided with a water inlet, an exhaust outlet, and a liquid inlet pipe 21. The liquid inlet pipe 21 is connected to a first ball valve 41. The main radiator includes a liquid inlet, which is connected to an outlet pipe 6. The liquid inlet of the main radiator is connected to a second ball valve 42 through the outlet pipe 6.

[0043] Specifically, the monitoring unit includes a first temperature and pressure sensor 71 and a temperature and humidity pressure sensor 72. The first temperature and pressure sensor 71 is located at the coolant inlet of the fuel cell engine and is used to monitor the pressure value of the water field in the fuel cell engine. The temperature and humidity pressure sensor 72 is located at the air inlet of the fuel cell engine and is used to monitor the air pressure value of the fuel cell engine. It should be noted that the fuel cell unit also includes an engine controller. Both the first temperature and pressure sensor 71 and the temperature and humidity pressure sensor 72 are connected to the engine controller and can transmit the monitored water field pressure value and air pressure value to the engine controller.

[0044] In detail, the purging mechanism includes an air compressor and an intercooler arranged sequentially along the air intake direction. The outlet of the intercooler is connected to the air intake, and the outlet of the intercooler is also connected to the pressure relief box 3.

[0045] In this embodiment, the first ball valve 41, the second ball valve 42, and the third ball valve 43 are all electric ball valves and are all connected to the engine controller.

[0046] It should be noted that a heating component is also provided between the coolant inlet and coolant outlet of the fuel cell engine. The heating unit includes a PTC heater 81 and a thermostat 82. In this way, the system of the present invention can heat the coolant at low temperatures.

[0047] Example 2

[0048] This invention also discloses a method for eliminating static pressure in the water field of a fuel cell engine stack. The method employs the static pressure elimination system described above to eliminate static pressure in the water field of the fuel cell engine stack. The method includes...

[0049] Step S1: First, the fuel cell engine is shut down, and the connection between the fuel cell engine and the heat dissipation unit is disconnected. Specifically, by controlling the closing of the first ball valve 41 and the second ball valve 42, the fuel cell engine and the heat dissipation unit 2 can be isolated, so that the coolant of the heat dissipation unit 2 no longer flows to the fuel cell engine.

[0050] Step S2: By opening the third ball valve 43, the fuel cell engine and the pressure relief tank 3 are connected, the static pressure of the fuel cell engine stack water field is released, and part of the coolant is discharged into the pressure relief tank 3. The discharged coolant presses the elastic film or piston in the middle of the pressure relief tank 3 to one side.

[0051] Step S3: Collect the water field pressure value of the fuel cell engine system and determine whether the pressure value is zero;

[0052] Step S4: When the pressure value is zero, close the third ball valve 43 to disconnect the fuel cell engine from the pressure relief box 3, and the fuel cell engine continues to stop, thereby protecting the fuel cell membrane electrode assembly.

[0053] Step S5: Before restarting the fuel cell engine, open the first ball valve 41 and the second ball valve 42, and keep the third ball valve 43 closed. At this time, the fuel cell engine and the heat dissipation unit 2 are connected.

[0054] Step S6: Collect the air pressure value of the fuel cell engine. If the air pressure value reaches the specified value P1, open the third ball valve 43 to connect the fuel cell engine and the pressure relief box 3, thereby discharging the coolant in the pressure relief box 3. At this time, the gas pressure will press the elastic diaphragm or piston in the pressure relief box 3 to the opposite side.

[0055] Step S7: Disconnect the connection between the fuel cell engine and the pressure relief box 3, and the fuel cell engine will operate normally.

[0056] Specifically, in step S6, the coolant in the pressure relief tank 3 is forced out by the gas pressure from the purging mechanism into the cooling system of the fuel cell engine and the heat dissipation unit 2.

[0057] It should be noted that in step S4, when the pressure value is not zero, a manual inspection is performed to determine whether there is any abnormality in the device and pipeline.

[0058] In summary, the static pressure relief system for the fuel cell engine stack water field protected by this invention is based on a fuel cell unit and includes a heat dissipation unit, a purging mechanism, and a pressure relief unit. The pressure relief unit comprises a first ball valve located between the heat dissipation unit and the water pump inlet, a second ball valve located between the fuel cell engine coolant outlet and the heat dissipation unit, and a third ball valve and a pressure relief tank located between the purging mechanism and the water pump inlet. Using the cooperation of these structures, the system operates as follows: When the fuel cell engine stops, the first and second ball valves are closed, thereby isolating the fuel cell engine and the heat dissipation unit and preventing coolant from flowing from the heat dissipation unit to the fuel cell engine. Then, the third ball valve is opened, and the static pressure in the fuel cell stack water field is released into the pressure relief tank through the third ball valve and pipeline, while some coolant is discharged. The discharged coolant enters the pressure relief tank. The pressure value of the fuel cell engine water field is monitored by a monitoring unit. When the pressure value is zero, the third ball valve is closed, and the engine stops, thereby effectively protecting the fuel cell membrane electrode assembly (MEA). Furthermore, before starting the fuel cell engine, the first and second ball valves are opened while the third ball valve remains closed. At this time, the fuel cell engine and the cooling unit are normally connected. After the fuel cell engine starts, the air pressure value of the fuel cell engine is monitored by the monitoring unit. When the air pressure value reaches the set pressure, the third ball valve is opened, and the gas pressure from the purging mechanism is applied to the pressure relief box, which re-pressurizes the coolant in the pressure relief box into the cooling system. Then the third ball valve is closed, and the engine runs normally. In this way, the static pressure of the fuel cell stack water field can be quickly eliminated after the fuel cell engine stops, thereby effectively improving engine performance and increasing engine life.

[0059] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A hydrostatic pressure elimination system for a fuel cell engine stack water field, characterized in that: include, Purging mechanism; A fuel cell unit includes a fuel cell engine and a water pump connected to the fuel cell engine. The fuel cell engine has a purge inlet, a coolant inlet, and a coolant outlet. The purge mechanism is connected to the purge inlet. The fuel cell unit also includes a monitoring unit for monitoring the water pressure and air pressure of the engine. A heat dissipation unit is connected to the fuel cell engine via the coolant inlet and coolant outlet; The pressure relief unit includes a ball valve assembly and a pressure relief box. The ball valve assembly includes a first ball valve, a second ball valve, and a third ball valve. The first ball valve is disposed between the heat dissipation unit and the water pump inlet. The second ball valve is disposed between the coolant outlet and the heat dissipation unit. The purging mechanism is connected to the water pump inlet through the pressure relief box and the third ball valve. The third ball valve is disposed between the water pump inlet and the purging mechanism. The pressure relief box is equipped with an elastic element, which is movably connected to the inner wall of the pressure relief box and moves along the pressure direction.

2. The hydrostatic pressure elimination system for a fuel cell engine stack according to claim 1, characterized in that: The elastic element is an elastic film or a piston.

3. The hydrostatic pressure elimination system for a fuel cell engine stack according to claim 1, characterized in that: The heat dissipation unit includes a main radiator and an expansion tank connected to each other. The liquid outlet of the main radiator is connected to a first ball valve, and the liquid inlet of the main radiator is connected to a second ball valve.

4. The hydrostatic pressure elimination system for a fuel cell engine stack according to claim 1, characterized in that: The monitoring unit includes a first temperature and pressure sensor and a temperature and humidity pressure sensor. The first temperature and pressure sensor is located at the coolant inlet, and the temperature and humidity pressure sensor is located at the air inlet of the fuel cell engine.

5. The hydrostatic pressure elimination system for a fuel cell engine stack according to claim 1, characterized in that: The purging mechanism includes an air compressor and an intercooler arranged sequentially along the air intake direction. The outlet of the intercooler is connected to the purging air inlet, and the outlet of the intercooler is also connected to the pressure relief box.

6. A method for eliminating static pressure in the water field of a fuel cell engine stack, characterized in that: The static pressure in the water field of the fuel cell engine stack is eliminated using the static pressure elimination system as described in any one of claims 1-5, the method comprising: Step S1: The fuel cell engine is shut down, and the connection between the fuel cell engine and the heat dissipation unit is disconnected; Step S2: Connect the fuel cell engine and the pressure relief box to release the static pressure of the fuel cell engine stack water field; Step S3: Collect the pressure value of the water field of the fuel cell engine stack and determine whether the pressure value is zero; Step S4: When the pressure value is zero, disconnect the fuel cell engine from the pressure relief box; Step S5: Before restarting the fuel cell engine, connect the fuel cell engine and the cooling unit, and keep the connection between the fuel cell engine and the pressure relief box disconnected. Step S6: Collect the air pressure value of the fuel cell engine and determine whether the air pressure value reaches the specified value P1. If the air pressure value reaches the specified value P1, connect the fuel cell engine and the pressure relief box to discharge the coolant in the pressure relief box. Step S7: Disconnect the connection between the fuel cell engine and the pressure relief box.

7. The method for eliminating static pressure in the water field of a fuel cell engine stack according to claim 6, characterized in that: In step S6, the coolant in the pressure relief tank is discharged to the cooling system of the fuel cell engine and the heat dissipation unit.

8. The method for eliminating static pressure in the water field of a fuel cell engine stack according to claim 6, characterized in that: In step S2, the fuel cell engine and the pressure relief tank are connected, allowing some of the coolant to be discharged into the pressure relief tank.

9. A method for eliminating static pressure in the water field of a fuel cell engine stack according to claim 6, characterized in that: In step S4, when the pressure value is not zero, a manual inspection is performed.

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