An improved fuel cell system insulation device and method

Abstract

The application discloses a kind of to promote fuel cell system insulation device and method, including S1, fuel cell system electric pile c is powered on, into standby state, wait for start-up instruction, if receiving start-up instruction, then enter step S2;S2, carry out pre-start safety state monitoring, if monitoring passes through, then enter step S3;S3, in turn execute high-pressure water jet instruction, cathode three-way valve t is switched to tail position, execute air purge instruction, complete after entering step S4;S4, complete fuel cell normal start-up procedure, enter operating state;By rotating air jet head g and rotating water jet head h use clean air of fuel cell air circuit and pure water generated by fuel cell work, regularly to group valve body are purged, maintain, avoid long time use dust, water accumulation after caused insulation resistance reduction and material aging problem.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, and in particular to a device and method for improving the insulation of a fuel cell system. Background Technology

[0002] As fuel cell systems become increasingly powerful, the demand for integration also grows, and the volumetric power ratio requirement becomes higher. This is accompanied by increasingly higher requirements for system integration. At this point, the three-chamber combined valve of the fuel cell system can save space to the maximum extent and replace the original silicone tubing solution. However, because the three-chamber combined valve body integrates the fuel cell cooling circuit, it needs to ensure a sufficiently high insulation resistance value, which requires the selection of insulating materials with high dielectric constant.

[0003] After the combined valve body was completely replaced with insulating material, the insulation problem was solved in the short term. However, the metal sensors installed on the combined valve body were directly connected to the coolant. As the insulating material surface accumulated over time, the dust and other dirt that accumulated on the surface of the insulating material came into contact with rainwater or tap water sprayed on it during car washes. This connected the metal joints, sensors and other metal components on the combined valve body to the fuel cell housing (ground), causing a serious insulation failure in the system. Summary of the Invention

[0004] The purpose of this invention is to provide a device and method for improving the insulation of a fuel cell system, so as to solve the problem of serious insulation failure in the system mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: An insulation enhancement device for a fuel cell system includes a fuel cell system stack, a tailpipe water distributor silencer, and a water storage tank. The fuel cell system stack is provided with port one and port two; The tail drain silencer is equipped with port three, port four and port five; The water storage tank is equipped with port six, port seven and port eight; The port 1 is connected in series via pipelines to a cathode three-way valve, an intercooler, a two-stage booster air compressor, an air filter, and an air inlet. Port 2 is connected in series with back pressure valve e and port 3 via pipelines; Port 4 is connected to the exhaust port via a pipeline; The cathode three-way valve and the intercooler are connected in series via pipelines, including a jet solenoid valve and a rotary jet head. Port 5 and port 6 are connected by a pipeline; The seventh port is connected in series via a pipeline to a water spray solenoid valve and a rotary spray head.

[0006] Preferably, the eight ports are connected in series via pipes to a drain solenoid valve and a drain outlet. Port 8 is connected to one end of the water pump via the drain solenoid valve, and the other end of the water pump is connected to port 7 via the spray solenoid valve.

[0007] Preferably, the system also includes a combined valve body, on which the rotary water nozzle and the rotary air nozzle are integrated, and the two are positioned at different heights on the combined valve body, forming a preset spray angle with the mounting surface of the combined valve body.

[0008] Preferably, the water storage tank is equipped with a liquid level sensor 1 and a liquid level sensor 2.

[0009] Preferably, the fuel cell system stack is equipped with an online insulation monitoring device.

[0010] Preferably, the combined valve body includes a cooling circuit combined valve body, the upper part of which is provided with a metal component for external connection, and the cooling circuit combined valve body is provided with a plurality of mounting holes.

[0011] A method for improving the insulation of a fuel cell system includes the following steps: S1. The fuel cell system stack is powered on and enters standby mode, waiting for the power-on command. If the power-on command is received, proceed to step S2. S2. Perform a pre-power-on safety status monitoring. If the monitoring passes, proceed to step S3. S3. Execute the high-pressure water spray command in sequence, switch the cathode three-way valve to the tail position, execute the air purging command, and proceed to step S4 after completion; S4. Complete the normal startup procedure for the fuel cell and enter the running state; S5. During operation, determine whether an external shutdown command has been received. If so, proceed to the shutdown process; otherwise, proceed to step S6. S6. Check if the water level in the storage tank is above the first liquid level threshold. If the level is greater than the first liquid level threshold, the drain solenoid valve is opened to drain the water until the level drops to less than or equal to the first liquid level threshold, then proceed to step S7. S7. If either of the following conditions is met: the fuel cell system stack running time is greater than or equal to time 1, or the combined valve body insulation resistance is less than resistance 1, then execute the high-pressure water spray command, switch the cathode three-way valve to the tail position, and execute the air purging command in sequence. After execution, return to step S4. Otherwise, return directly to step S4.

[0012] Preferably, the pre-power-on safety status monitoring in step S2 specifically includes: S21. If the insulation resistance of the combined valve body is detected to be less than that of resistor two, proceed to step S22; if the insulation resistance is not less than that of resistor two, otherwise switch the cathode three-way valve to the tail position and execute the air purging command, then proceed to step S4. S22. Determine whether the liquid level in the detection tank is greater than the second liquid level threshold. If it is greater than the second liquid level threshold, proceed to step S3. If it is not greater than the second liquid level threshold, switch the cathode three-way valve to the tail position and execute the air purging command, then proceed to step S4.

[0013] Preferably, the shutdown process in step S5 includes the following steps: S51. Upon receiving the shutdown command, check whether the water level in the storage tank is greater than the second water level threshold. If it is greater than the second water level threshold, proceed to step S52; if it is not greater than the second water level threshold, proceed to step S53. S52. Execute the high-pressure water spray command in sequence, switch the cathode three-way valve to the tail position, execute the air purging command, and then return to step S1; S53. Execute the air purging command, and then return to step S1.

[0014] Preferably, the high-pressure water spraying command is: start the water pump, then open the water spraying solenoid valve, continuously spray for a first preset time, and repeat the execution once every two time intervals, for a total of at least one preset number of times; The air purging command is as follows: start the two-stage booster air compressor, then open the jet solenoid valve, and continue purging for a second preset time, repeating the process once every three time intervals, for a total of at least two preset number of times.

[0015] The beneficial effects of this invention are: 1. By using the clean air from the fuel cell air circuit and the pure water generated by the fuel cell operation through the rotating jet head g and the rotating water spray head h, the combined valve body is regularly purged and maintained to avoid the problems of reduced insulation resistance and material aging caused by dust and water accumulation after long-term use.

[0016] 2. By refining the air purging command scheme and purging strategy, purging maintenance can be carried out for fuel cells during startup, operation, shutdown, and long-term storage. Attached Figure Description

[0017] Fig. 1 This is a schematic diagram of the system structure according to an embodiment of the present invention; Fig. 2 This is a schematic diagram of the method flow according to an embodiment of the present invention; Fig. 3 This is a schematic diagram of the combined valve body according to an embodiment of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Please see Figs. 1-3 The present invention provides an insulation improvement device for a fuel cell system, including a fuel cell system stack c, a tailpipe water distributor d, and a water storage tank q; The fuel cell system stack c is provided with port one and port two; The tail drain silencer d is equipped with port three, port four and port five; The water storage tank q is equipped with port six, port seven and port eight; The port 1 is connected in series via pipelines to a cathode three-way valve t, an intercooler s, a two-stage booster air compressor b, an air filter a, and an air inlet. Port 2 is connected in series with back pressure valve e and port 3 via pipelines; Port 4 is connected to the exhaust port via a pipeline; The cathode three-way valve t and the intercooler s are connected in series via pipelines, and a jet solenoid valve f and a rotary jet head g are connected in series. Port 5 and port 6 are connected by a pipeline; The port seven is connected in series via a pipeline to a water spray solenoid valve j and a rotary spray head h.

[0020] Specifically, the port eight is connected in series with a drain solenoid valve m and a drain outlet via a pipeline; The port eight is connected to one end of the water pump k between the drain solenoid valve m and the drain solenoid valve m, and the other end of the water pump k is connected to the port seven between the water spray solenoid valve j.

[0021] Specifically, it also includes a combined valve body r, on which the rotating water spray head h and the rotating air jet head g are integrated, and the two are set at different heights on the combined valve body r, and respectively form a preset spray angle with the mounting surface of the combined valve body r.

[0022] The jet nozzle and water spray nozzle are installed 30cm above the combination valve, with a spray angle of 45 degrees.

[0023] Specifically, the water storage tank q is equipped with a liquid level sensor n and a liquid level sensor P.

[0024] Specifically, the fuel cell system stack c is equipped with an online insulation monitoring instrument u.

[0025] Specifically, the combined valve body r includes a cooling circuit combined valve body 3, the upper part of which is provided with a metal part 1 for external connection, and the cooling circuit combined valve body 3 is provided with a plurality of mounting holes 2.

[0026] Among them, 1 and 2: metal-cased sensors or other metal connectors in the cooling circuit are directly connected to the power generation unit through the coolant; the metal component can be directly equivalent to a charged unit. 3: The cooling circuit combined valve body is not limited to the three-chamber insulated combined valve body, and the dielectric constant meets the insulation requirements; 4. The insulating valve body has mounting bolt holes. The bolts are metal parts that are directly fixed to the fuel cell shell, directly connected to the ground, and can be directly touched by hand. Operating principle: The above connector is the fuel cell cooling circuit connector, and the connector material is PPS. The fuel cell cooling fluid collects the temperature and pressure of the fuel cell cooling fluid through the sensor 1 / 2 integrated in the above connector. Since the fuel cell cooling fluid is directly connected to the power generation unit, the insulation purpose is achieved only by controlling the conductivity of the cooling fluid. The 1 / 2 sensor is a metal component that is directly connected to the cooling fluid. If the surface of the above insulating material fails to be clean, it will cause 4 and 1 / 2 to become connected through the material surface, causing the insulation of the system to fail.

[0027] The specific operation process based on the above embodiments is as follows: Function 1 – Hot Air Purging: During the operation of the fuel cell system, ambient air is filtered through an air filter and then compressed by an air compressor to a working gas pressure of up to 200 kPa, with the air temperature rising to about 180°C. After being cooled by an intercooler, the temperature drops to about 80°C. The air from this location is led out through a bypass pipeline to the top of the insulating valve body, and the combined valve body is purged by controlling the opening and closing of the jet solenoid valve. This purging method uses a high jet temperature, which can not only remove dust from the valve body surface, but also quickly evaporate water stains on the valve body surface if it is wet, keeping the valve body dry. At the same time, if the valve body surface is frozen due to water accumulation, hot air purging can quickly melt the ice and snow on the valve body surface. Function 2 - Deionized Water Flushing: The water generated by the fuel cell system is separated by a water silencer, and some of the water will accumulate in the water storage tank. The water in the storage tank has extremely low conductivity. When the combined valve body needs to be cleaned, first turn on the water pump to circulate, and then turn on the water spray valve. The deionized water from the spray head will evenly clean the surface of the valve body and wash away the stubborn impurities attached to the surface. Function 3 - Combined Cleaning: First, use deionized water to rinse the surface, and then use hot air to dry it after rinsing. Function 1 is suitable for daily intermittent purging, rainy day purging, and low-temperature purging; Function 2 is suitable for cleaning in specific scenarios, such as purging during malfunctions, or before and after the system has been parked for a long time. Function 3 is applicable to system shutdown purging.

[0028] A method for improving the insulation of a fuel cell system includes the following steps: S1. The fuel cell system stack c is powered on and enters standby mode, waiting for the power-on command. If the power-on command is received, proceed to step S2. S2. Perform a pre-power-on safety status monitoring. If the monitoring passes, proceed to step S3. S3. Execute the high-pressure water spray command in sequence, switch the cathode three-way valve t to the tail position, execute the air purging command, and proceed to step S4 after completion; S4. Complete the normal startup procedure for the fuel cell and enter the running state; S5. During operation, determine whether an external shutdown command has been received. If so, proceed to the shutdown process; otherwise, proceed to step S6. S6. Check if the water level q in the storage tank is greater than the first liquid level threshold. If the level is greater than the first liquid level threshold, the drain solenoid valve m is opened to drain the water until the level drops to less than or equal to the first liquid level threshold, then proceed to step S7. S7. If the fuel cell system stack operating time is greater than or equal to 30 minutes, or the insulation resistance of the combined valve body is less than 1 MΩ, If either of these two conditions is met, the high-pressure water spray command, the cathode three-way valve t being switched to the tail position, and the air purging command will be executed sequentially. After execution, the process will return to step S4. Otherwise, the process will directly return to step S4.

[0029] Wherein, the first liquid level threshold is a level signal from the liquid level sensor at point n. If the water level is higher than this liquid level value, the sensor will output a high-level signal; n=1.

[0030] Specifically, the pre-power-on safety status monitoring in step S2 includes: S21. If the insulation resistance of the combined valve body r is detected to be less than 1... Then proceed to step S22; if the insulation resistance is not less than 1 Otherwise, switch the cathode three-way valve t to the tail position and execute the air purging command, then proceed to step S4; S22. Determine whether the liquid level in the detection water tank q is greater than the second liquid level threshold. If it is greater than the second liquid level threshold, proceed to step S3. If it is not greater than the second liquid level threshold, switch the cathode three-way valve t to the tail position and execute the air purging command, then proceed to step S4.

[0031] Specifically, the shutdown procedure in step S5 includes the following steps: S51. Upon receiving the shutdown command, check if the water level in the storage tank q is greater than the second water level threshold. If it is greater than the second water level threshold, proceed to step S52; otherwise, proceed to step S53. S52. Execute the high-pressure water spray command sequentially, switch the cathode three-way valve t to the tail position, execute the air purging command, and then return to step S1; S53. Execute the air purging command, and then return to step S1.

[0032] Specifically, the high-pressure water spraying command is as follows: start the water pump k, then open the water spraying solenoid valve j, continuously spray for a first preset time, and repeat the execution once every 2 seconds, for a total of at least 10 times; The air purging command is as follows: start the two-stage booster air compressor b, then open the jet solenoid valve f, and continue purging for a second preset time, repeating the process once every 1 second, for a total of at least 20 times.

[0033] Wherein, the second liquid level threshold is a level signal from the liquid level sensor at point p. If the water level is higher than this value, the sensor will output a high-level signal; if it is lower than this value, the sensor will output a low-level signal. Below the second liquid level: p=0, n=0; Above the second liquid level, below the first liquid level: p=1, n=0; Greater than the first liquid level: p=1, n=1.

[0034] The first preset time is 2 seconds, and the second preset time is 1 second.

[0035] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A device for improving the insulation of a fuel cell system, characterized in that: Includes fuel cell system stack (c), tailpipe water separator (d) and water storage tank (q); The fuel cell system stack (c) is provided with port one and port two; The tail drain silencer (d) is equipped with port three, port four and port five; The water storage tank (q) is equipped with port six, port seven and port eight; The port 1 is connected in series via pipelines to a cathode three-way valve (t), an intercooler (s), a two-stage booster air compressor (b), an air filter (a), and an air inlet; Port 2 is connected in series with a back pressure valve (e) and port 3 via pipelines; Port 4 is connected to the exhaust port via a pipeline; The cathode three-way valve (t) and the intercooler (s) are connected in series via pipelines, with a jet solenoid valve (f) and a rotary jet head (g) connected in series. Port 5 and port 6 are connected by a pipeline; The port seven is connected in series via a pipeline to a water spray solenoid valve (j) and a rotary water spray head (h).

2. The device for improving the insulation of a fuel cell system according to claim 1, characterized in that: The port eight is connected in series via pipes to a drain solenoid valve (m) and a drain outlet. The port eight is connected to one end of the water pump (k) between the drain solenoid valve (m) and the other end of the water pump (k), and the port seven is connected to the water spray solenoid valve (j).

3. The device for improving insulation in a fuel cell system according to claim 1, characterized in that: It also includes a combined valve body (r), on which the rotating water spray head (h) and the rotating jet head (g) are integrated, and the two are set at different heights on the combined valve body (r), and respectively form a preset spray angle with the mounting surface of the combined valve body (r).

4. The device for improving the insulation of a fuel cell system according to claim 1, characterized in that: The water storage tank (q) is equipped with a liquid level sensor (n) and a liquid level sensor (P).

5. The device for improving the insulation of a fuel cell system according to claim 3, characterized in that: An online insulation monitoring instrument (u) is installed on the fuel cell system stack (c).

6. The device for improving the insulation of a fuel cell system according to claim 3, characterized in that: The combined valve body (r) includes a cooling circuit combined valve body (3), the upper part of which is provided with a metal part (1) for external connection, and the cooling circuit combined valve body (3) is provided with a plurality of mounting holes (2).

7. A method for implementing the insulation device of a fuel cell system according to any one of claims 1 to 6, characterized in that, Includes the following steps: Step S1: The fuel cell system stack (c) is powered on and enters standby mode, waiting for the power-on command. If the power-on command is received, proceed to step S2. Step S2: Perform a pre-power-on safety status monitoring. If the monitoring passes, proceed to step S3. Step S3: Execute the high-pressure water spray command in sequence, switch the cathode three-way valve (t) to the tail position, execute the air purging command, and proceed to step S4 after completion; Step S4: Complete the normal startup procedure for the fuel cell and enter the running state; Step S5: During operation, determine whether an external shutdown command has been received. If so, proceed to the shutdown process; otherwise, proceed to step S6. Step S6: Detect whether the water storage tank (q) is greater than the first liquid level threshold; If the level is greater than the first liquid level threshold, the drain solenoid valve (m) is opened to drain the water until the level drops to less than or equal to the first liquid level threshold, then proceed to step S7. S7. If either of the following conditions is met: the operating time of the fuel cell system stack (c) is greater than or equal to time 1, or the insulation resistance of the combined valve body (r) is less than resistance 1, then execute the high-pressure water spray command, switch the cathode three-way valve (t) to the tail position, and execute the air purging command in sequence. After execution, return to step S4. Otherwise, return directly to step S4.

8. A method for improving the insulation device of a fuel cell system according to claim 7, characterized in that: The pre-power-on safety status monitoring in step S2 specifically includes: S21. If the insulation resistance of the combined valve body (r) is detected to be less than that of resistor two, proceed to step S22; if the insulation resistance is not less than that of resistor two, otherwise switch the cathode three-way valve (t) to the tail position and execute the air purging command, then proceed to step S4. S22. Determine whether the liquid level of the detection water tank (q) is greater than the second liquid level threshold. If it is greater than the second liquid level threshold, proceed to step S3. If it is not greater than the second liquid level threshold, switch the cathode three-way valve (t) to the tail position and execute the air purging command, then proceed to step S4.

9. A method for improving the insulation device of a fuel cell system according to claim 7, characterized in that: The shutdown procedure in step S5 includes the following steps: S51. Upon receiving the shutdown command, check whether the liquid level in the water storage tank (q) is greater than the second liquid level threshold. If it is greater than the second liquid level threshold, proceed to step S52; if it is not greater than the second liquid level threshold, proceed to step S53. S52. Execute the high-pressure water spray command in sequence, switch the cathode three-way valve (t) to the tail position, execute the air purging command, and then return to step S1; S53. Execute the air purging command, and then return to step S1.

10. A method for improving the insulation device of a fuel cell system according to claim 7, characterized in that: The high-pressure water spraying command is as follows: start the water pump (k), then open the water spraying solenoid valve (j), continuously spray for a first preset time, and repeat the execution once every two time intervals, for a total of at least one preset number of times; The air purging command is as follows: start the two-stage booster air compressor (b), then open the jet solenoid valve (f), and continue purging for a second preset time, repeating the operation once every three time intervals, for a total of at least two preset number of times.

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