An integrated air control device and a vehicle-mounted fuel cell engine

Abstract

The present invention provides an integrated air control device, belonging to the technical field of fuel cell engines, which solves the problems that the control logic of the existing air control device is complex and the bypass valve is not opened in time, which is likely to cause the compressor to surge. The device includes a compressor, an electronically controlled three-way valve and a controller. The outlet of the compressor is integrally connected to the inlet of the electronically controlled three-way valve, that is, both the main path outlet and the bypass outlet of the electronically controlled three-way valve serve as the outlet of the compressor; the controller is used to determine the rotational speed of the compressor and the bypass outlet opening degree that meet the required flow rate after receiving the required flow rate sent by the vehicle, and control the compressor to operate at the above-mentioned rotational speed and bypass outlet opening degree; and, respectively monitor the air flow rate and pressure at the inlet and the main path outlet of the compressor in real time, input them into a preset flow rate-pressure ratio-efficiency model, and judge whether the compressor is likely to surge and whether the efficiency is too low. If it is likely to surge or the efficiency is too low, adjust the compressor to stay away from surging and improve the efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cell engines, and particularly to an integrated air control device and a vehicle-mounted fuel cell engine. Background Art

[0002] An air compressor is a very important component in a vehicle-mounted fuel cell engine, mainly providing the required air flow rate and air inlet pressure for the fuel cell. The vehicle-mounted fuel cell engine has relatively high requirements for both the air flow rate and pressure, and requires the air compressor to have a relatively high rotational speed and a relatively small power.

[0003] In existing vehicle-mounted fuel cell engines, there are many components, the integration degree is relatively low, and the system integration is relatively cumbersome. It is necessary to simultaneously control the air compressor, the intake throttle valve, and the bypass valve to control the inlet flow rate and pressure of the air path, making the control logic relatively complex. Moreover, it is easy to cause the air compressor to surge, and even cause damage to the air compressor.

[0004] In the prior art, the problem of air compressor surge is generally solved by connecting the outlet of the air compressor to a three-way valve, but the bypass outlet of the three-way valve not being opened in time will still cause the air compressor to surge. Summary of the Invention

[0005] An embodiment of the present invention aims to provide an integrated air control device to solve the problems that the control logic of the existing air control device is complex and the bypass valve not being opened in time is likely to cause the air compressor to surge.

[0006] On the one hand, an embodiment of the present invention provides an integrated air control device, including an air compressor, an electronically controlled three-way valve, and a controller; wherein,

[0007] The outlet of the air compressor is integrally connected to the inlet of the electronically controlled three-way valve, so that both the main path outlet and the bypass outlet of the electronically controlled three-way valve serve as the outlet of the air compressor;

[0008] The controller is configured to, after receiving the required flow rate sent by the whole vehicle, determine the rotational speed of the air compressor and the bypass outlet opening degree that meet the required flow rate, and control the air compressor to operate at the above rotational speed and bypass outlet opening degree; and respectively and real-time monitor the air flow rate and pressure at the inlet and the main path outlet of the air compressor, input them into a preset flow rate-pressure ratio-efficiency model, judge whether the air compressor is likely to surge and whether the efficiency is too low, and if it is likely to surge or the efficiency is too low, adjust the rotational speed of the air compressor and the bypass outlet opening degree to make it away from surge and improve the efficiency.

[0009] The beneficial effects of the above technical solution are as follows: The air compressor and the three-way valve are integrated, and only one controller is needed to control the air compressor and the three-way valve, improving the overall integration of the entire fuel cell engine. Through the bypass function of the air compressor, the air compressor surge can be effectively avoided. When the operating state of the air compressor (i.e., the air flow rate and pressure at the inlet and the main path outlet of the air compressor) is close to the air compressor surge protection limit or the efficiency is too low, the rotational speed and the bypass outlet opening degree of the air compressor are automatically adjusted through the integrated control logic, enabling the air compressor to stay away from surge and improve efficiency.

[0010] Based on the further improvement of the above device, the controller is further configured to, after receiving the shutdown command sent by the vehicle, by controlling the opening degrees of the main path outlet and the bypass outlet of the air compressor, make the air flow rate at the main path outlet reach a preset purge flow rate into the stack, and continuously supply purge air into the stack for a preset time, and then close the main path outlet.

[0011] The beneficial effect of the above further improvement solution is that during the shutdown process of the fuel cell engine, purging is required. By controlling the opening degrees of the main path and the bypass path, the flow rate of the purge gas into the stack is controlled.

[0012] The controller is further configured to, after receiving the shutdown command sent by the vehicle, close the main path outlet of the air compressor and open the bypass outlet, so that the main path is sealed.

[0013] The beneficial effect of the above further improvement solution is that after the fuel cell engine shuts down, the outlet of the air compressor is automatically controlled to completely switch to the bypass path, thereby closing the main path, achieving the sealing effect, and avoiding air leakage into the stack and causing damage to the fuel cell stack.

[0014] The controller is further configured to identify whether the vehicle is temporarily parked; and if it is temporarily parked, increase the rotational speed of the air compressor and the opening degree of the bypass outlet, so that the net output power of the fuel cell engine on the vehicle remains zero.

[0015] The beneficial effect of the above further improvement solution is that when operating at a specific working condition point of temporary parking, by increasing the power of the air compressor to consume the net output power of the system, the net output of the fuel cell engine is kept zero, which is beneficial to reducing losses.

[0016] The controller includes:

[0017] A data acquisition unit, arranged at the inlet and the main path outlet of the air compressor, for real-time monitoring of the air flow rate and pressure at the arranged positions and sending them to the data processing and control unit;

[0018] A data processing and control unit, which is configured to determine the rotational speed and bypass outlet opening degree of an air compressor that meet the required flow rate after receiving the required flow rate sent by the whole vehicle, control the operation of the air compressor through an execution unit; and input the air flow rate and pressure at the inlet and main path outlet of the air compressor into a preset flow rate - pressure ratio - efficiency model to determine whether the air compressor may surge and whether the efficiency is too low. If surging may occur or the efficiency is too low, control the air compressor through the execution unit to keep it away from surging and improve the efficiency.

[0019] An execution unit, which is configured to adjust the rotational speed of the air compressor and the opening degrees of the main path outlet and bypass outlet according to the control of the data processing and control unit.

[0020] The beneficial effect of the above further improvement scheme is that: based on the air flow rate and pressure at the inlet and main path outlet of the air compressor, the position of the air compressor operating in the map (pre - calibrated flow rate - pressure ratio - efficiency model or curve) can be obtained. If it is close to the surge limit of the air compressor (the highest pressure ratio at the same air flow rate) or the working efficiency is low, the rotational speed of the air compressor and the opening degree of the bypass outlet can be adjusted to make the air compressor operate in a region farther from the surge limit and more efficiently.

[0021] The integrated air control device further includes an air filter;

[0022] The outlet of the air filter is integrally connected to the inlet of the air compressor, so that the outlet of the air filter serves as the inlet of the air compressor.

[0023] The beneficial effect of the above further improvement scheme is that: adding an air filter can filter impurities in the air, effectively improving the service life of the air compressor and even the service life of the entire integrated air control device and even the fuel cell engine.

[0024] The data processing and control unit executes the following program to control the air compressor to stay away from surging and improve the efficiency:

[0025] After receiving the required flow rate q1 sent by the whole vehicle, determine the minimum rotational speed and bypass outlet opening degree of the air compressor that meet the required flow rate;

[0026] Control the air compressor to operate at the above - mentioned minimum rotational speed and bypass outlet opening degree through the execution unit, so that the flow rate at the main path outlet of the air compressor is equal to q1;

[0027] Obtain the air pressure P1 at the inlet of the air compressor and the air pressure P2 at the main path outlet, and determine the pressure ratio ε through the following formula

[0028] ε = P2 / P1

[0029] Obtain the air flow rate q at the inlet of the air compressor, input the flow rate q and the pressure ratio ε into a preset flow rate - pressure ratio - efficiency model to obtain the efficiency of the air compressor at the current moment and the surge limit; the surge limit is the highest pressure ratio at the flow rate q.

[0030] Obtain the difference between the pressure ratio ε and the above-mentioned surge limit, compare the difference with a first threshold to determine whether the air compressor may surge. If the difference is less than the first threshold, it is determined that the air compressor may surge, and the execution unit is used to control the air compressor to increase the bypass outlet opening degree so that the air compressor operates in a region farther from the surge limit.

[0031] Compare the efficiency of the air compressor with a second threshold to determine whether the efficiency of the air compressor is too low. If it is less than the second threshold, the execution unit is used to control the air compressor to increase the rotational speed so that the air compressor operates in a more efficient region, and then perform the above determination of whether it may surge again until the air compressor operates in a region farther from the surge limit and the efficiency of the air compressor is greater than or equal to the second threshold.

[0032] The beneficial effect of the above further improvement solution is that when the operating state is close to the surge protection line of the air compressor, the bypass path is automatically opened through the integrated control logic to avoid the air compressor from surging.

[0033] Further, the controller executes the following program to identify whether the vehicle is temporarily parked and complete the regulation of temporary parking:

[0034] Monitor the vehicle speed, determine whether the vehicle speed within a preset time period before the current moment is all zero. If so, determine that the vehicle is temporarily parked and execute the next step; otherwise, determine that the vehicle is not temporarily parked and continue to monitor the vehicle speed.

[0035] Obtain the power consumption A of the air compressor, the power consumption B of other components except the air compressor in the vehicle-mounted fuel cell engine, and the total output power of the fuel cell stack is C.

[0036] Determine the net output power D of the vehicle-mounted fuel cell engine through the following formula

[0037] D = C - A - B

[0038] Conduct the regulation of temporary parking according to the above net output power D. If D > 0, increase the rotational speed of the air compressor and the bypass outlet opening degree; if D < 0, decrease the rotational speed of the air compressor and the bypass outlet opening degree, and judge again until D = 0, and keep the rotational speed of the air compressor and the bypass outlet opening degree unchanged to complete the regulation of temporary parking.

[0039] The beneficial effects of the above further improvement solution are as follows: The control logic for specific working conditions (temporary parking) is added. During temporary parking, the net output power of the fuel cell engine is consumed by increasing the power of the air compressor, so that the net output of the system remains zero. At this time, the fuel cell engine does not generate electricity, but the air compressor still consumes less power at a low speed. The purpose is that when parking, the air compressor and other components are still in the working state, and the vehicle can respond more quickly when it starts moving again. If the air compressor and other components are shut down during temporary parking, it will take a long time to meet the system requirements when running again.

[0040] On the other hand, an embodiment of the present invention provides a vehicle-mounted fuel cell engine including the above integrated air control device, further including a stack, a hydrogen injection device, and a mixing exhaust pipe; wherein,

[0041] The air inlet of the stack is connected to the main path outlet of the integrated air control device, and the hydrogen inlet is connected to the output end of the hydrogen injection device; the gas outlet of the stack and the bypass outlet of the integrated air control device are respectively connected to the output end of the mixing exhaust pipe.

[0042] The beneficial effects of adopting the above technical solution are as follows: Using fewer components can increase the integration of the system. When the operating state of the air compressor is close to the surge protection line (also called the surge protection limit, surge limit), the controller can avoid the air compressor from surging by opening the bypass path for pressure relief, achieving the purpose of protecting the air compressor.

[0043] Based on the further improvement of the above system, the system further includes an intercooler, a humidifier, and an engine controller;

[0044] The intercooler and the humidifier are sequentially arranged between the main path outlet of the air compressor and the air inlet of the stack, and the control ends are respectively connected to the output end of the engine controller;

[0045] The engine controller is configured to determine the required output power of the stack according to the control instruction of the vehicle, the real-time vehicle speed of the vehicle, and the power of all the electrical devices started in the vehicle; and, determine the required flow rate of the air that the integrated air control device should output according to the output power of the stack; and send the required flow rate to the controller of the integrated air control device.

[0046] The beneficial effects of adopting the above further improvement solution are as follows: The intercooler, the humidifier, and the control logic are added, which can automatically control the operating state of the air compressor away from surge and improve the efficiency.

[0047] The purpose of providing the Summary of the Invention section is to introduce the selection of concepts in a simplified form, which will be further described in the following Detailed Description section. The Summary of the Invention section is not intended to identify the key features or essential features of the present disclosure, nor is it intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The above and other objects, features, and advantages of the present disclosure will become more apparent by describing the exemplary embodiments of the present disclosure in more detail with reference to the accompanying drawings, in which, in the exemplary embodiments of the present disclosure, the same reference numerals generally represent the same components.

[0049] Figure 1 Fig. 6 shows a schematic diagram of the composition of the integrated air control device in Embodiment 1;

[0050] Figure 2 Fig. 10 shows a schematic diagram of the composition of the integrated air control device in Embodiment 2;

[0051] Figure 3 Fig. 14 shows a schematic diagram of the control principle for avoiding compressor surge in Embodiment 2;

[0052] Figure 4 Fig. 18 shows a schematic diagram of the control logic for temporary parking in Embodiment 2.

[0053] Reference numerals:

[0054] 1 - Air filter; 2 - Flowmeter; 3 - Compressor motor, providing power to the compressor; 4 - Compressor with bypass function; 5 - Controller; 6 - Intercooler; 7 - Flowmeter at the bypass outlet; 8 - Humidifier; 9 - Stack; 10 - Hydrogen injection device; 11 - Hydrogen source; 12 - Mixed exhaust pipe. Detailed implementation manners

[0055] Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the embodiments of the present disclosure are shown in the 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.

[0056] As used herein, the term "including" and its variants mean open inclusion, that is, "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "at least partially based on". The terms "an exemplary embodiment" and "an embodiment" mean "at least one exemplary embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc. may refer to different or the same objects. There may also be other explicit and implicit definitions below.

[0057] Embodiment 1

[0058] An embodiment of the present invention discloses an integrated air control device, including a compressor, an electronically controlled three-way valve, and a controller.

[0059] The air compressor is a centrifugal air compressor used in a fuel cell engine, and is used to provide the inlet gas that meets the air flow and pressure requirements.

[0060] The electronically controlled three-way valve is a valve controlled by voltage or current and has one inlet and two outlets (the main path outlet and the bypass outlet).

[0061] The outlet of the air compressor is integrally connected to the inlet of the electronically controlled three-way valve, so that both the main path outlet and the bypass outlet of the electronically controlled three-way valve serve as the outlet of the air compressor.

[0062] The controller is used to determine the rotational speed of the air compressor and the opening degree of the bypass outlet that meet the required flow rate after receiving the required flow rate sent by the vehicle, and control the air compressor to operate at the above rotational speed and bypass outlet opening degree; and, respectively, monitor the air flow rate and pressure at the inlet and the main path outlet of the air compressor in real time, input them into a preset flow rate-pressure ratio-efficiency model, and judge whether the air compressor is likely to surge and whether the efficiency is too low. If the air compressor is likely to surge or the efficiency is too low, adjust the rotational speed of the air compressor and the opening degree of the bypass outlet to keep it away from surging and improve the efficiency.

[0063] Specifically, the preset flow rate-pressure ratio-efficiency model may be the preset flow rate-pressure ratio-efficiency model described in Embodiment 2 (that is, first calculate the pressure ratio ε, input the inlet flow rate q and the pressure ratio ε into the calibrated flow rate-pressure ratio-efficiency curve to obtain the surge limit and the efficiency of the air compressor at the current moment), or may be a pre-trained deep neural network (for example, the input is the air flow rate and pressure at the inlet and the main path outlet of the air compressor, and the output is the result of whether the air compressor is likely to surge and whether the efficiency is too low). Those skilled in the art can understand and will not be elaborated here.

[0064] Compared with the prior art, the integrated air control device provided in this embodiment integrates the air compressor and the three-way valve, and at the same time only one controller is needed to control the air compressor and the three-way valve, improving the overall integration of the entire fuel cell engine. Through the bypass function of the air compressor, the surge of the air compressor can be effectively avoided. When the operating state of the air compressor (that is, the air flow rate and pressure at the inlet and the main path outlet of the air compressor) is close to the surge protection limit of the air compressor or the efficiency is too low, the rotational speed of the air compressor and the opening degree of the bypass outlet are automatically adjusted through the integrated control logic, so that the air compressor can be kept away from surging and the efficiency can be improved.

[0065] Embodiment 2

[0066] On the basis of Embodiment 1, for optimization, the controller is further used to, after receiving the shutdown instruction sent by the vehicle, control the opening degrees of the main path outlet and the bypass outlet of the air compressor, so that the air flow rate at the main path outlet reaches the preset inlet stack purge flow rate, and continuously provide the inlet stack purge air for a preset time, and then close the main path outlet.

[0067] Preferably, after receiving the startup instruction sent by the whole vehicle, the controller is further configured to control the opening degrees of the main road outlet and the bypass outlet of the air compressor, so that the air flow rate at the main road outlet reaches the preset in-pile purging flow rate, and continuously supply the in-pile purging air for a preset time.

[0068] Preferably, after receiving the shutdown instruction sent by the whole vehicle, the controller is further configured to close the main road outlet of the air compressor and open the bypass outlet, so that the main road is sealed. That is, after closing the main road outlet, the bypass outlet can be opened to seal the main road.

[0069] Preferably, the controller further includes a data acquisition unit, a data processing and control unit, and an execution unit that are connected in sequence.

[0070] The data acquisition unit is arranged at the inlet and the main road outlet of the air compressor, and is used for real-time monitoring of the air flow rate and pressure at the arranged positions and sending them to the data processing and control unit.

[0071] Preferably, the data acquisition unit further includes pressure sensors and flow meters arranged at the inlet and the main road outlet of the air compressor, as Figure 2 shown.

[0072] The data processing and control unit is configured to determine the rotation speed of the air compressor and the opening degree of the bypass outlet that meet the required flow rate after receiving the required flow rate sent by the whole vehicle, and control the operation of the air compressor through the execution unit; and input the air flow rate and pressure at the inlet and the main road outlet of the air compressor into a preset flow rate-pressure ratio-efficiency model to judge whether the air compressor may surge and whether the efficiency is too low. If surging may occur or the efficiency is too low, control the air compressor through the execution unit to keep it away from surging and improve the efficiency.

[0073] The execution unit is configured to adjust the rotation speed of the air compressor and the opening degrees of the main road outlet and the bypass outlet according to the control of the data processing and control unit.

[0074] Preferably, the integrated air control device further includes an air filter for filtering impurities in the air.

[0075] The outlet of the air filter is integrally connected to the inlet of the air compressor, so that the outlet of the air filter serves as the inlet of the air compressor.

[0076] Preferably, as Figure 3 shown, the data processing and control unit executes the following program to control the air compressor to keep away from surging and improve the efficiency:

[0077] S1. After receiving the required flow rate q1 sent by the whole vehicle, determine the minimum rotation speed of the air compressor and the opening degree of the bypass outlet that meet the required flow rate;

[0078] S2. Control the air compressor to operate at the above-mentioned minimum speed and bypass outlet opening through the execution unit, so that the flow rate at the main path outlet of the air compressor is equal to the q1;

[0079] S3. Obtain the air pressure P1 at the inlet of the air compressor and the air pressure P2 at the main path outlet, and determine the pressure ratio ε through the following formula

[0080] ε = P2 / P1 (1)

[0081] S4. Obtain the air flow rate q at the inlet of the air compressor, input the flow rate q and the pressure ratio ε into the preset flow rate - pressure ratio - efficiency model to obtain the efficiency of the air compressor at the current moment and the surge limit; the surge limit is the highest pressure ratio at the flow rate q;

[0082] S5. Obtain the difference between the pressure ratio ε and the above-mentioned surge limit, compare the difference with the first threshold to judge whether the air compressor may surge. If the difference is less than the first threshold, it is determined that the air compressor may surge, and the execution unit is used to control the air compressor to increase the bypass outlet opening, so that the air compressor works in an area farther from the surge limit;

[0083] S6. Compare the efficiency of the air compressor with the second threshold to judge whether the efficiency of the air compressor is too low. If it is less than the second threshold, the execution unit is used to control the air compressor to increase the speed, so that the air compressor works in a more efficient area, and then execute the above judgment of whether it may surge again until the air compressor works in an area farther from the surge limit and the efficiency of the air compressor is greater than or equal to the second threshold.

[0084] Preferably, the controller is further configured to identify whether the vehicle is temporarily parked; and if it is temporarily parked, increase the speed of the air compressor and the bypass outlet opening, so that the net output power of the fuel cell engine on the vehicle remains zero.

[0085] Preferably, as Figure 4 shown, the controller executes the following program to identify whether the vehicle is temporarily parked and complete the regulation of temporary parking:

[0086] S7. Monitor the vehicle speed, and determine whether the vehicle speeds within a preset time period before the current moment are all zero. If so, determine that the vehicle is temporarily parked and execute the next step. Otherwise, determine that the vehicle is not temporarily parked and continue to monitor the vehicle speed;

[0087] S8. Obtain the power consumption A of the air compressor, the power consumption B of other components except the air compressor in the vehicle-mounted fuel cell engine, and the total output power of the fuel cell stack is C;

[0088] S9. Determine the net output power D of the vehicle-mounted fuel cell engine through the following formula

[0089] D = C - A - B (2)

[0090] S10. Adjust the temporary parking according to the above net output power D. If D>0, increase the rotational speed of the air compressor and the opening degree of the bypass outlet. If D<0, decrease the rotational speed of the air compressor and the opening degree of the bypass outlet. Then judge again until D = 0, and keep the rotational speed of the air compressor and the opening degree of the bypass outlet unchanged to complete the adjustment of the temporary parking.

[0091] Compared with Embodiment 1, the integrated air control device provided in this embodiment has the following beneficial effects:

[0092] 1. When the air compressor stops running, the outlet of the air compressor automatically switches to the bypass path. At this time, the main path is in a sealed state, which can realize the sealing of the fuel cell air path and avoid the loss of the fuel cell stack caused by the leakage of the main path and the formation of a hydrogen-oxygen interface due to air entering the stack.

[0093] 2. When the fuel cell system shuts down, by controlling the opening degree of the three-way valve, the air compressor can be used to purge the fuel cell stack or reduce the tailpipe hydrogen concentration.

[0094] 3. The integrated controller can avoid the air compressor from surging by opening the bypass path to release pressure when the operating state of the air compressor is close to the surge protection line, achieving the purpose of protecting the air compressor.

[0095] 4. Achieve zero power output (similar to the standby state). During vehicle driving, in order to achieve temporary parking without stopping the operation of the fuel cell system, by controlling the opening degree of the main path and increasing the rotational speed of the air compressor, the inlet flow rate into the stack can be kept unchanged until the power generated by the fuel cell stack is equal to the power consumed by the components. At this time, the output of the fuel cell stack is all used to supply the consumption of the components, and the net output is zero, enabling the vehicle to start quickly when it hits the road again, and at the same time avoiding the loss of the fuel cell engine caused by frequent switching on and off.

[0096] 5. Using fewer components can increase the integration degree of the system.

[0097] Embodiment 3

[0098] Another embodiment of the present invention discloses a vehicle-mounted fuel cell engine including the integrated air control device described in Embodiment 1 or 2. The system further includes a fuel cell stack, a hydrogen injection device, and a mixing and exhaust pipe.

[0099] Among them, the air inlet of the fuel cell stack is connected to the outlet of the main path of the integrated air control device, and the hydrogen inlet is connected to the output end of the hydrogen injection device; the gas outlet of the fuel cell stack and the bypass outlet of the integrated air control device are respectively connected to the output end of the mixing and exhaust pipe.

[0100] The fuel cell stack, as the most core component of the fuel cell engine, is used to provide electrical energy.

[0101] The mixing and exhaust pipe serves as a gas mixing and exhaust pipeline.

[0102] Compared with the prior art, the fuel cell engine provided in this embodiment uses fewer components, which can increase the system integration. When the operating state of the air compressor is close to the surge protection line (surge limit), the controller can avoid the air compressor from surging by opening the bypass passage to relieve pressure, achieving the purpose of protecting the air compressor.

[0103] Embodiment 4

[0104] Based on the optimization of Embodiment 3, the on-vehicle fuel cell engine further includes an intercooler, a humidifier, and an engine controller.

[0105] The intercooler and the humidifier are sequentially arranged between the main road outlet of the air compressor and the air inlet of the fuel cell stack, and their control ends are respectively connected to the output end of the engine controller.

[0106] The engine controller is configured to determine the required output power of the fuel cell stack according to the control instruction of the vehicle, the real-time vehicle speed, and the power of all the electrical devices started inside the vehicle; and determine the required air flow rate that the integrated air control device should output according to the output power of the fuel cell stack; and send the required flow rate to the controller of the integrated air control device.

[0107] The embodiments of the present disclosure have been described above. The above description is exemplary and not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art in the technical field without departing from the scope and spirit of the described embodiments. The selection of the terms used herein is intended to best explain the principles of the embodiments, the practical application, or the improvement of the prior art, or to enable other ordinary skill in the art in the technical field to understand the disclosed embodiments.

Claims

1. An integrated air control device, characterized in that, It includes an air compressor, an electronically controlled three-way valve, and a controller; among them, The outlet of the air compressor is integrally connected to the inlet of the electronically controlled three-way valve, so that both the main path outlet and the bypass outlet of the electronically controlled three-way valve serve as the outlet of the air compressor; The controller is used to determine the rotational speed of the air compressor and the bypass outlet opening degree that meet the required flow rate after receiving the required flow rate sent by the whole vehicle, and control the air compressor to operate at the above rotational speed and bypass outlet opening degree; and, respectively, monitor the air flow rate and pressure at the inlet and the main path outlet of the air compressor in real time, input them into a preset flow rate - pressure ratio - efficiency model, obtain the surge limit and the efficiency of the air compressor, and judge whether the air compressor may surge and whether the efficiency is too low. If it may surge or the efficiency is too low, adjust the rotational speed of the air compressor and the bypass outlet opening degree to keep it away from surge and improve the efficiency. The controller is further used to, after receiving the shutdown instruction sent by the whole vehicle, control the opening degrees of the main path outlet and the bypass outlet of the air compressor, so that the air flow rate at the main path outlet reaches a preset in-pile purging flow rate, and continuously provide in-pile purging air for a preset time and then close the main path outlet; the controller is further used to, after receiving the shutdown instruction sent by the whole vehicle, close the main path outlet of the air compressor and open the bypass outlet to make the main path sealed. The controller is further used to identify whether the vehicle is temporarily parked; and if it is temporarily parked, increase the rotational speed of the air compressor and the bypass outlet opening degree so that the net output power of the fuel cell engine on the whole vehicle remains zero. The controller further includes: A data acquisition unit, arranged at the inlet and the main path outlet of the air compressor, used to monitor the air flow rate and pressure at the arranged positions in real time and send them to the data processing and control unit; The data processing and control unit is used to determine the rotational speed of the air compressor and the bypass outlet opening degree that meet the required flow rate after receiving the required flow rate sent by the whole vehicle, and control the operation of the air compressor through the execution unit; and input the air flow rate and pressure at the inlet and the main path outlet of the air compressor into a preset flow rate - pressure ratio - efficiency model, judge whether the air compressor may surge and whether the efficiency is too low. If it may surge or the efficiency is too low, control the air compressor through the execution unit to keep it away from surge and improve the efficiency; The execution unit is used to adjust the rotational speed of the air compressor and the opening degrees of the main path outlet and the bypass outlet according to the control of the data processing and control unit. It further includes an air filter; The outlet of the air filter is integrally connected to the inlet of the air compressor, so that the outlet of the air filter serves as the inlet of the air compressor; The data processing and control unit executes the following program to control the air compressor to keep away from surge and improve the efficiency: After receiving the required flow rate q1 sent by the whole vehicle, determine the minimum rotational speed of the air compressor and the bypass outlet opening degree that meet the required flow rate; Control the air compressor to operate at the above minimum rotational speed and bypass outlet opening degree through the execution unit, so that the flow rate at the main path outlet of the air compressor is equal to the q1; Obtain the air pressure P1 at the inlet of the air compressor and the air pressure P2 at the main path outlet, and determine the pressure ratio ε through the following formula ε = P2 / P1 Obtain the air flow rate q at the inlet of the air compressor, input the flow rate q and the pressure ratio ε into a preset flow rate - pressure ratio - efficiency model to obtain the efficiency of the air compressor at the current moment and the surge limit; the surge limit is the highest pressure ratio at the flow rate q. Obtain the difference between the pressure ratio ε and the above-mentioned surge limit, compare the difference with a first threshold to determine whether the air compressor may surge. If the difference is less than the first threshold, it is determined that the air compressor may surge, and the execution unit is used to control the air compressor to increase the bypass outlet opening degree, so that the air compressor operates in a region far from the surge limit. Compare the efficiency of the air compressor with a second threshold to determine whether the efficiency of the air compressor is too low. If it is less than the second threshold, the execution unit is used to control the air compressor to increase the rotational speed, so that the air compressor operates in a more efficient region, and then execute the above determination of whether it may surge again until the air compressor operates in a region far from the surge limit and the efficiency of the air compressor is greater than or equal to the second threshold. The controller executes the following program to identify whether the vehicle is temporarily parked and complete the regulation of temporary parking: Monitor the vehicle speed, and determine whether the vehicle speeds within a preset time period before the current moment are all zero. If so, it is determined that the vehicle is temporarily parked and the next step is executed. Otherwise, it is determined that the vehicle is not temporarily parked, and continue to monitor the vehicle speed. Obtain the power consumption A of the air compressor, the power consumption B of other components except the air compressor in the on-vehicle fuel cell engine, and the total output power of the fuel cell stack is C. Determine the net output power D of the on-vehicle fuel cell engine through the following formula D = C - A - B Conduct the regulation of temporary parking according to the above net output power D. If D > 0, increase the rotational speed of the air compressor and the bypass outlet opening degree. If D < 0, decrease the rotational speed of the air compressor and the bypass outlet opening degree, and judge again until D = 0, and keep the rotational speed of the air compressor and the bypass outlet opening degree unchanged to complete the regulation of temporary parking.

2. A vehicle-mounted fuel cell engine comprising the integrated air control device according to claim 1, characterized in that, It also includes a fuel cell stack, a hydrogen injection device, and a mixing exhaust pipe; among them, The air inlet of the fuel cell stack is connected to the main road outlet of the integrated air control device, and the hydrogen inlet is connected to the output end of the hydrogen injection device; the gas outlet of the fuel cell stack and the bypass outlet of the integrated air control device are respectively connected to the output end of the mixing exhaust pipe.

3. The on-vehicle fuel cell engine according to claim 2, characterized in that, It also includes an intercooler, a humidifier, and an engine controller; The intercooler and the humidifier are sequentially arranged between the main road outlet of the air compressor and the air inlet of the fuel cell stack, and the control ends are respectively connected to the output end of the engine controller; The engine controller is used to determine the required output power of the fuel cell stack according to the control instruction of the vehicle, the real-time vehicle speed of the vehicle, and the power of all electrical equipment started in the vehicle; And determine the required flow rate of the air that the integrated air control device should output according to the output power of the fuel cell stack; And send the required flow rate to the controller of the integrated air control device.

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