Generated power distribution method based on fuel cell system, controller and fuel cell system

Abstract

The invention relates to the technical field of fuel cells, and particularly provides a generation power distribution method based on a fuel cell system, a controller and the fuel cell system. The fuel cell system comprises a secondary cell and N fuel cells connected in parallel. The method comprises the following steps: determining the external required power of the fuel cell system, the internal consumed power of the system and the actual charging and discharging power of the secondary cell; determining the total required power of the fuel cell system according to the external required power, the internal consumed power of the system and the actual charging and discharging power; determining the number M of fuel cells needing to be called according to the total required power and the target power interval; m fuel cells are selected from the N fuel cells connected in parallel, the M fuel cells supply power to the outside with the generated power P, the value of P is determined according to the total demand power and M, and therefore distribution of the generated power between the fuel cells connected in parallel in the fuel cell system can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a power distribution method based on a fuel cell system, a controller and a fuel cell system. Background Art

[0002] Fuel cells, especially proton exchange membrane fuel cells (PEMFC), have been widely used in scenarios such as fuel cell electric vehicles and fuel cell backup power supplies due to their advantages such as no pollution, high specific energy, low noise and high energy conversion rate.

[0003] With the continuous development of science and technology, the requirements for power sources are becoming more and more diversified. For example, in some scenarios, the power source needs to be able to provide high power to the outside. At this time, when a single fuel cell provides electricity to the outside, it may be difficult to meet the high power requirements. Therefore, connecting multiple fuel cells in parallel as a fuel cell system to supply power to the outside is an important direction of technological development in the fuel cell field.

[0004] In a fuel cell system, how to distribute the generated power among the parallel fuel cells is a crucial issue. Summary of the invention

[0005] In view of the defects existing in the prior art, the purpose of the present invention is to provide a power distribution method, a controller and a fuel cell system based on a fuel cell system, aiming to solve the problems in the prior art to a certain extent.

[0006] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0007] The embodiment of the present application provides a method for distributing power generated by a fuel cell system, wherein the fuel cell system includes a secondary battery and N fuel cells connected in parallel, wherein N is a positive integer greater than 1, and the method includes:

[0008] Determining the external power demand of the fuel cell system, the internal power consumption of the system, and the actual charge and discharge power of the secondary battery;

[0009] Determining the total required power of the fuel cell system according to the external required power, the internal power consumed by the system and the actual charging and discharging power;

[0010] Determine the number M of fuel cells to be called according to the total required power and the target power range, wherein the target power range is associated with the optimal power range corresponding to each fuel cell, M is a positive integer greater than or equal to 1, and M is less than or equal to N;

[0011] M fuel cells are selected from the N parallel-connected fuel cells, and each of them supplies power to the outside with a generated power P, wherein the value of P is determined according to the total required power and M.

[0012] Preferably, the internal power consumption of the fuel cell system is determined in the following manner:

[0013] Obtaining the power consumption of the fuel cell system, the power consumption of the energy storage converter and the power consumption of other core components in the fuel cell system;

[0014] The internal power consumption of the system is calculated according to the power consumption of the fuel-electric system, the power consumption of the energy storage converter and the power consumption of other core components.

[0015] Preferably, the actual charge and discharge power of the secondary battery is determined in the following manner:

[0016] P SOC =(SOC 实际 -SOC Base )×P 额定 ×ɑ;

[0017] Among them, P SOC is the actual charge and discharge power of the secondary battery; SOC 实际 is the actual power of the secondary battery; SOC Base is the reference power of the secondary battery; 额定 is the rated power of the secondary battery; ɑ is a weight factor, wherein ɑ is greater than 0.

[0018] Preferably, each of the parallel-connected fuel cells has a corresponding optimal power range; and,

[0019] The method further comprises:

[0020] The intersection between the optimal power intervals corresponding to the fuel cells connected in parallel is determined, and the intersection is determined as the target power interval.

[0021] Preferably, each of the fuel cells connected in parallel has a corresponding optimal power range; and,

[0022] The method further comprises:

[0023] The optimal power interval corresponding to any fuel cell is determined as the target power interval.

[0024] Preferably, the target power range is greater than or equal to Pmin and less than or equal to Pmax; and,

[0025] According to the total required power and the target power range, the number of fuel cells M to be called is determined, specifically including:

[0026] According to the total required power, Pmin and Pmax, the evaluation parameters Nmin, Nmax, Lmin and Lmax are calculated; wherein Nmin is the integer ratio of the total required power to Pmin, Nmax is the integer ratio of the total required power to Pmax, Lmin is the remainder of the ratio of the total required power to Pmin, and Lmax is the remainder of the ratio of the total required power to Pmin;

[0027] If Nmin is equal to 0, the value of M is 1;

[0028] When Nmin is not equal to 0, if Nmax is greater than N, the value of M is N;

[0029] When Nmin is greater than 0 and Nmax is less than or equal to N, if Lmin is equal to 0, the value of M can be Nmin;

[0030] When Nmin is greater than 0, Nmax is less than or equal to N, and Lmin is not equal to 0, if Lmax is equal to 0, the value of M can be Nmax;

[0031] When Nmin is greater than 0, Nmax is less than or equal to N, Lmin is not equal to 0, and Lmax is not equal to 0, the value of M can be Nmin.

[0032] Preferably, in the process where the selected M fuel cells each supply power to the outside with the generated power P, if it is monitored that the M fuel cells include a faulty fuel cell, the method further includes: restarting the faulty fuel cell.

[0033] Preferably, if the faulty fuel cell still has the fault after restarting, the method further comprises:

[0034] The power generation power P of the fuel cell that is still faulty after restarting is evenly distributed to the other fuel cells in the M fuel cells.

[0035] The present application also provides a controller, which uses the method provided in an embodiment of the present application to distribute the power generation of N parallel fuel cells in a fuel cell system, wherein the fuel cell system includes a secondary battery and N parallel fuel cells.

[0036] The present application also provides a fuel cell system, which includes a secondary battery, N fuel cells connected in parallel, and a controller provided in an embodiment of the present application.

[0037] On the basis of the above technical solution, compared with the prior art, the advantages of the present invention are:

[0038] The power distribution method based on the fuel cell system provided by the embodiment of the present application is adopted. The fuel cell system includes a secondary battery and N parallel fuel cells. The method includes determining the external power demand of the fuel cell system, the internal power consumption of the system and the actual charge and discharge power of the secondary battery, and then determining the total power demand of the fuel cell system according to the external power demand, the internal power consumption of the system and the actual charge and discharge power, and then determining the number of fuel cells M to be called according to the total power demand and the target power interval, wherein the target power interval is associated with the optimal power interval corresponding to each fuel cell, and then selecting M fuel cells from the N parallel fuel cells, and each of them supplies power to the outside with the power generation power P, and the value of P is the ratio of the total power demand to M. Therefore, through the method provided by the embodiment of the present application, it is possible to realize the distribution of power generation between each parallel fuel cell in the fuel cell system, thereby solving the problems in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic diagram of the specific structure of the fuel cell system provided in this application.

[0040] Figure 2 A schematic diagram of a specific flow chart of a power distribution method based on a fuel cell system provided in this application. DETAILED DESCRIPTION

[0041] The embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0042] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0043] In the description of the present application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device including a series of elements includes not only those elements, but also other elements that are not explicitly listed, or also includes elements inherent to such a process, method, article, or device. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the process, method, article, or device including the elements.

[0044] As mentioned above, in some scenarios, the power supply needs to be able to provide high power to the outside. At this time, when a single fuel cell provides electricity to the outside, it may be difficult to meet the high power requirement. Therefore, connecting multiple fuel cells in parallel to provide power to the outside as a fuel cell system is an important direction for the development of fuel cell technology. In a fuel cell system, how to distribute the generated power between the parallel fuel cells is a crucial issue.

[0045] In view of this, an embodiment of the present application provides a power distribution method based on a fuel cell system, which can be used to distribute power to fuel cells in the fuel cell system, thereby solving the problems in the prior art.

[0046] For ease of understanding, the structure of the fuel cell system provided in the embodiment of the present application may be briefly described here. Figure 1 The figure shows a schematic diagram of the specific structure of the fuel cell system 10, which includes a secondary battery 11 and N parallel fuel cells 12. The N fuel cells 12 are connected in parallel to each other and are all connected to the secondary battery 11, so as to facilitate the supply of power to the secondary battery 11. For example, when the power of the secondary battery 11 is insufficient, the secondary battery 11 can be supplied with power through the fuel cell 12, so that the secondary battery 11 can be charged. N is a positive integer greater than 1, for example, N can be 2, 3, 4, 5 or other positive integers.

[0047] In addition, the fuel cell system 10 may further include an energy storage inverter 13, and each fuel cell 12 and secondary battery 11 are connected to the energy storage inverter 13, so that electric energy can be output to external equipment through the energy storage inverter 13. That is to say, the energy storage inverter 13 can output the electric energy generated by the fuel cell 12 to the outside, and can also output the electric energy stored in the secondary battery 11 to the outside.

[0048] Of course, the fuel cell system 10 may also include a fuel-electric system, other core components, and other auxiliary components, etc. The fuel-electric system includes an air compressor, a humidifier, a hydrogen circulation pump, etc. in the fuel cell, and other core components may include components such as a fuel cell stack in the fuel cell. Of course, other auxiliary components may include, for example, a fuel cell housing, etc. Among them, during the operation of the fuel cell in the fuel cell system 10, the fuel-electric system and other core components may cause internal power loss, while other auxiliary components are not likely to cause internal power loss.

[0049] It should be noted that the structure of the fuel cell 12 in the embodiment of the present application can also be described here. The fuel cell 12 may include a stack, and the stack may include multiple fuel cell monomers connected in series. Each fuel cell monomer may include a proton exchange membrane, a catalyst, a gas diffusion layer, a bipolar plate, an end plate, etc. For example, multiple fuel cell monomers are connected in series to obtain the stack, and then combined with a protective shell to form the fuel cell 12. In this way, multiple fuel cells 12 are connected in parallel, and further combined with a secondary battery 11, etc., to obtain the fuel cell system 10 in the embodiment of the present application.

[0050] It should be further explained that for each fuel cell 12, due to limitations such as its own structure, such as the number of fuel cell monomers connected in series, the water content of the proton exchange membrane, the efficiency of the air compressor, etc., there will be a corresponding optimal power range. Within this optimal power range, the power generation efficiency and energy conversion rate of the fuel cell are relatively high. When the optimal power range is exceeded (for example, greater than the maximum value of the range, or less than the minimum value of the range), the power generation efficiency and energy conversion rate of the fuel cell may decrease.

[0051] In the embodiment of the present application, since there are multiple fuel cells 12 connected in parallel in the fuel cell system 10, the optimal power intervals corresponding to each of the parallel fuel cells 12 may be the same or different. In addition, the fuel cell system is also provided with a target power interval, which is associated with the optimal power interval corresponding to each fuel cell 12. In practical applications, the target power interval can be determined by the optimal power interval corresponding to each fuel cell 12.

[0052] For example, in one method, when these parallel fuel cells 12 are the same fuel cells (for example, the rated parameters are not much different), the optimal power ranges corresponding to each of them are usually not much different. Therefore, the optimal power range corresponding to any fuel cell can be used as the target power range, and the actual working power of each fuel cell 12 can be controlled within the target power range.

[0053] Of course, in another way, when these parallel fuel cells 12 are different fuel cells (for example, the rated parameters of some fuel cells differ greatly), there may be a situation where the optimal power ranges of some fuel cells 12 differ greatly. In this embodiment of the present application, the intersection of the optimal power ranges of each parallel fuel cell 12 can be determined, and the intersection can be determined as the target power range, thereby controlling the actual operating power of each fuel cell 12 within the target power range.

[0054] like Figure 2 The figure shows a specific flow chart of a method for distributing power generated by a fuel cell system provided by an embodiment of the present application. The method includes the following steps:

[0055] Step S21: Determine the external power demand of the fuel cell system, the internal power consumption of the system, and the actual charge and discharge power of the secondary battery.

[0056] Specifically, the external required power refers to the power that the fuel cell system needs to output to the external device. For example, the fuel cell system is connected to an electrical device (i.e., the external device). At this time, the electrical device needs to operate at a target power. At this time, the power that the fuel cell system needs to output is the target power. In other words, the target power is the external required power.

[0057] The internal power consumption of the system specifically refers to the internal power consumption caused by resistance and other reasons inside the fuel cell system. In the structure of the fuel cell system mentioned above, the fuel-electric system, the energy storage inverter and other core components may cause internal power consumption. Therefore, the internal power consumption of the fuel cell system can be determined in the following way. The power consumption of the fuel-electric system, the power consumption of the energy storage inverter and the power consumption of other core components in the fuel cell system can be obtained first, and then the internal power consumption of the system can be calculated based on the power consumption of the fuel-electric system, the power consumption of the energy storage inverter and the power consumption of other core components.

[0058] For example, the internal power consumption of the system can be calculated by the following formula 1:

[0059] Bop=Bop1+Bop2+Bop3 Formula 1

[0060] In Formula 1, Bop is the calculated internal power consumption of the system; Bop1 is the power consumption of the fuel-fired power system; Bop2 is the power consumption of the energy storage converter; and Bop3 is the power consumption of other core components.

[0061] In this way, after obtaining the power consumption Bop1 of the fuel cell system, the power consumption Bop2 of the energy storage converter and the power consumption Bop3 of other core components in the fuel cell system, they can be substituted into Formula 1 to calculate the internal power consumption Bop of the system.

[0062] In the fuel cell system provided in the embodiment of the present application, the secondary battery may be used as a power supply device to supply power to the outside. For example, when the secondary battery has a large amount of power, it may supply power to the outside. Of course, when the actual power of the secondary battery is low, the fuel cell may also need to be charged to increase its power.

[0063] Therefore, since the secondary battery has these two states, when determining the total required power of the fuel cell system, it is necessary to determine the actual charge and discharge power of the secondary battery. In practical applications, the actual charge and discharge power of the secondary battery can be determined by the following formula 2:

[0064] P SOC =(SOC 实际 -SOC Base )×P 额定 ×ɑ Formula 2

[0065] In Formula 2, P SOC is the actual charge and discharge power of the secondary battery; SOC 实际 is the actual power of the secondary battery; SOC Base is the reference power of the secondary battery; P 额定 is the rated power of the secondary battery; ɑ is the weight factor, where ɑ is greater than 0.

[0066] Among them, the rated power P of the secondary battery 额定 is the rated parameter of the secondary battery, which can be directly obtained; the weight factor ɑ can be set in advance, for example, a certain value can be set in advance as the weight factor ɑ according to actual needs, or the weight factor ɑ can be adjusted dynamically; the actual power SOC of the secondary battery 实际 , which can be obtained by actual measurement or read from the parameter panel of the secondary battery; for the reference power SOC of the secondary battery Base, can be set in advance in practical applications, and its physical meaning is that when the actual power of the secondary battery is greater than the reference power, the secondary battery is mainly discharged, and when the actual power of the secondary battery is less than the reference power, the secondary battery is mainly charged.

[0067] In practical applications, for example, a certain amount of power between 30% and 50% of the total power of the secondary battery can be set as the reference power SOC according to actual needs. Base .

[0068] Step S22: Determine the total required power of the fuel cell system according to the external required power, the internal power consumption of the system and the actual charging and discharging power.

[0069] The total power demand of the fuel cell system comprehensively reflects the demands of the fuel cell system for external power generation, internal consumption of the system, and actual charging and discharging of secondary batteries, and therefore reflects the total power demanded by each aspect.

[0070] In the embodiment of the present application, the total required power of the fuel cell system can be calculated by the following formula 3:

[0071] PSFC = PTG + P SOC + Bop Formula 3

[0072] In Formula 3, PSFC is the total required power of the fuel cell system; P SOC is the actual charge and discharge power of the secondary battery; Bop is the internal power consumption of the system; PTG is the external demand power. In other words, the actual charge and discharge power P of the secondary battery can be calculated SOC , the sum of the system's internal power consumption Bop and the external required power PTG, and the sum is used as the total required power PSFC of the fuel cell system.

[0073] Step S23: Determine the number M of fuel cells that need to be called according to the total required power and the target power range.

[0074] Wherein, M is a positive integer greater than or equal to 1, and M is less than or equal to N. In addition, as mentioned above, the target power range is associated with the optimal power range corresponding to each fuel cell.

[0075] Here, the specific implementation method of step S23 can be described in detail, wherein the target power interval is specifically greater than or equal to Pmin and less than or equal to Pmax, that is, the target power interval belongs to the interval of [Pmin, Pmax]. At this time, step S23 can calculate four evaluation parameters Nmin, Nmax, Lmin and Lmax according to the total required power PSFC, Pmin and Pmax. Specifically, the four evaluation parameters Nmin, Nmax, Lmin and Lmax can be calculated by formulas 4 to 7 as shown below:

[0076] Nmin=[PSFC / Pmin] Formula 4

[0077] Nmax=[PSFC / Pmax] Formula 5

[0078] Lmin=PSFC%Pmin Formula 6

[0079] Lmax=PSFC%Pmax Formula 7

[0080] In Formula 4 to Formula 7, [] is a rounding symbol; % is a remainder symbol; PSFC is the total required power of the fuel cell system. That is, Nmin is the integer ratio of PSFC to Pmin, Nmax is the integer ratio of PSFC to Pmax, Lmin is the remainder of the ratio of PSFC to Pmin, and Lmax is the remainder of the ratio of PSFC to Pmin. In this way, the four evaluation parameters Nmin, Nmax, Lmin and Lmax can be calculated through the above Formula 4 to Formula 7.

[0081] After obtaining the four evaluation parameters Nmin, Nmax, Lmin and Lmax, it can be determined whether Nmin is equal to 0. If Nmin is equal to 0, the value of M is 1. At this time, the number of fuel cells selected is 1, and the power generation power PFCN of the fuel cell can be PSFC, that is, the fuel cell can generate electricity with the power generation power PFCN.

[0082] When Nmin is not equal to 0, it can also be determined whether Nmax is greater than N. If Nmax is greater than N, the value of M is N. At this time, the number of fuel cells selected is N, that is, all fuel cells, and the power generation power PFCN of each fuel cell can be Pmax, that is, PFCN=Pmax.

[0083] In addition, when Nmin is greater than 0 and Nmax is less than or equal to N, if Lmin is equal to 0, the value of M can be Nmin, and the power generation power PFCN of the fuel cell can be Pmin, that is, PFCN=Pmin.

[0084] When Nmin is greater than 0, Nmax is less than or equal to N, and Lmin is not equal to 0, if Lmax is equal to 0, the value of M can be Nmax. At this time, the power generation power PFCN of the fuel cell can be Pmax, that is, PFCN=Pmax.

[0085] When Nmin is greater than 0, Nmax is less than or equal to N, Lmin is not equal to 0, and Lmax is not equal to 0, the value of M can be Nmin. At this time, the power generation power PFCN of the fuel cell can be the ratio of PSFC to M.

[0086] Step S24: M fuel cells are selected from the N parallel-connected fuel cells, and each of them supplies power to the outside with a generated power P.

[0087] The value of the generated power P needs to be determined based on the total required power of the fuel cell system and M. For example, the value of P can be the ratio of the total required power of the fuel cell system to M, that is, the generated power P=PSFC / M, wherein PSFC is the total required power of the fuel cell system, and in this power allocation method, the total required power PSFC is evenly distributed among the M fuel cells selected; of course, other power allocation methods can refer to the description of determining the value of M in the above step S23, which will not be repeated here.

[0088] In addition, there are many ways to select M fuel cells from N parallel fuel cells. For example, one way may be to randomly select M fuel cells from N parallel fuel cells; another way may be to first number the N parallel fuel cells, and then select M fuel cells from the N parallel fuel cells in the order of the numbers; another way may be to select M fuel cells from the N parallel fuel cells in combination with the health status of each fuel cell. For example, data such as the working time, stability, and water content of the proton exchange membrane of each fuel cell may be collected to determine the health status of each fuel cell, and then select M fuel cells with better health status from the N parallel fuel cells in combination with the health status of each fuel cell. Of course, in practical applications, other ways may be used to select M fuel cells from N parallel fuel cells, which are not limited here.

[0089] After M fuel cells are selected from the N parallel-connected fuel cells, each of the selected fuel cells supplies power to the outside at a power generation power P, thereby achieving distribution of the power generation power.

[0090] The power distribution method based on the fuel cell system provided by the embodiment of the present application is adopted. The fuel cell system includes a secondary battery and N parallel fuel cells. The method includes determining the external power demand of the fuel cell system, the internal power consumption of the system and the actual charge and discharge power of the secondary battery, and then determining the total power demand of the fuel cell system according to the external power demand, the internal power consumption of the system and the actual charge and discharge power, and then determining the number of fuel cells M to be called according to the total power demand and the target power interval, wherein the target power interval is associated with the optimal power interval corresponding to each fuel cell, and then selecting M fuel cells from the N parallel fuel cells, and each of them supplies power to the outside with the power generation power P, and the value of P is the ratio of the total power demand to M. Therefore, through the method provided by the embodiment of the present application, it is possible to realize the distribution of power generation between each parallel fuel cell in the fuel cell system, thereby solving the problems in the prior art.

[0091] It should be noted that in practical applications, the following power allocation method can usually be used. For example, when the fuel cell system supplies power to the outside, the external power demand (i.e., the PTG mentioned above) is directly divided by the number of parallel fuel cells (i.e., the N mentioned above) to determine the power generation of each fuel cell. However, this method does not take into account that in addition to the external power demand, there is also the internal power consumption of the system (i.e., the Bop mentioned above) and the actual charging and discharging of the secondary battery (the actual charging and discharging power is the PTG mentioned above). SOC ), so the calculated power generation power of the fuel cell is obviously not accurate; on the other hand, the external demand power is divided by the number of parallel fuel cells to calculate the power generation power of each fuel cell. Therefore, its essence is to directly supply power to the outside with all the parallel fuel cells, which makes it easy for the fuel cell to work in a non-optimal power range. For example, when the external demand power is relatively low, it is easy for the power supplied by the fuel cell to the outside to exceed its optimal power range, thereby affecting the power generation efficiency and energy conversion rate of the fuel cell system.

[0092] After the above step S24, M fuel cells are selected from the N parallel fuel cells, and each of them supplies power to the outside with the power generation power P. At this time, the M fuel cells in the fuel cell system can each continuously supply power to the outside with the power generation power P. However, in actual applications, fuel cells may fail, such as hydrogen leakage failure and water flooding fault light. These failures may be formed in the process of the fuel cell continuously supplying power to the outside with the power generation power P, or may exist before power generation. Therefore, in actual applications, it is usually necessary to monitor each fuel cell in the fuel cell system (including the M fuel cells) to determine whether these fuel cells have failures.

[0093] At this time, in the process of the selected M fuel cells each supplying power to the outside with the generated power P, if it is monitored that the M fuel cells include a faulty fuel cell, the embodiment of the present application may further provide measures.

[0094] Therefore, the method may also include restarting the faulty fuel cell. In practical applications, part of the fuel cell failure can be overcome by restarting. Therefore, for a faulty fuel cell, the method provided in the embodiment of the present application can first restart the faulty fuel cell.

[0095] Of course, after restarting the faulty fuel cell, there are two possibilities. One is that the fuel cell overcomes the fault by restarting, that is, the fault no longer exists after the fuel cell is restarted. This method does not require further adjustment of the power generation power of each of the M fuel cells, and the M fuel cells still supply power to the outside with the power generation power P; the other possibility is that the faulty fuel cell still exists after restarting, for example, the fault of the fuel cell is caused by flooding of the proton exchange membrane. At this time, restarting cannot overcome the fault. At this time, the faulty fuel cell is difficult to continue working, so it is necessary to redistribute the power generation power. In an embodiment of the present application, the redistribution method can be to evenly distribute the power generation power P of the fuel cell that still has a fault after restarting to other fuel cells among the M fuel cells.

[0096] Of course, after the reallocation, if the power generation power of other fuel cells among the M fuel cells exceeds their rated power, in order to avoid causing serious damage to the fuel cell, one processing method may be to re-execute the method provided in the present application, i.e., the above-mentioned steps S21 to S24, to redistribute the power generation power. Another processing method may be to start a non-working (in standby state) fuel cell from the N parallel fuel cells and issue a fault report.

[0097] As for the method of redistributing the generated power, that is, for the fuel cell that still has a fault after restarting, its generated power P is evenly distributed to the other fuel cells among the M fuel cells, that is, the fuel cells without faults among the M fuel cells, or the fuel cells that have overcome the faults after restarting. In this way, through this simple method, when there is a fault in the fuel cell and the fault is difficult to overcome by restarting, the distribution of generated power is further achieved.

[0098] Based on the power distribution method of the fuel cell system provided in the embodiment of the present application, the embodiment of the present application can also provide a controller, which uses the method provided in the embodiment of the present application to distribute the power of N parallel fuel cells in the fuel cell system. In practical applications, the controller can be, for example, an energy management unit (EMU) in the fuel cell system.

[0099] Of course, the embodiment of the present application can also provide a fuel cell system, which, in addition to processing a secondary battery and N parallel fuel cells, can also include the controller, and can then use the controller to distribute the power generation of the N parallel fuel cells.

[0100] The present invention is not limited to the above-mentioned embodiments. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention. The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

Claims

1. A method for distributing power generation based on a fuel cell system, characterized in that: The fuel cell system comprises a secondary battery and N fuel cells connected in parallel, wherein N is a positive integer greater than 1, and the method comprises: Determining the external power demand of the fuel cell system, the internal power consumption of the system, and the actual charge and discharge power of the secondary battery; Determining the total required power of the fuel cell system according to the external required power, the internal power consumed by the system and the actual charging and discharging power; Determine the number M of fuel cells to be called according to the total required power and the target power range, wherein the target power range is associated with the optimal power range corresponding to each fuel cell, M is a positive integer greater than or equal to 1, and M is less than or equal to N; M fuel cells are selected from the N parallel-connected fuel cells, and each of them supplies power to the outside with a generated power P, wherein the value of P is determined according to the total required power and M.

2. The method according to claim 1, characterized in that The internal power consumption of the fuel cell system is determined by: Obtaining the power consumption of the fuel cell system, the power consumption of the energy storage converter and the power consumption of other core components in the fuel cell system; The internal power consumption of the system is calculated according to the power consumption of the fuel-electric system, the power consumption of the energy storage converter and the power consumption of other core components.

3. The method according to claim 1, characterized in that The actual charge and discharge power of the secondary battery is determined by: P SOC =(SOC 实际 - SOC Base )×P 额定 ×ɑ; Among them, P SOC is the actual charge and discharge power of the secondary battery; SOC 实际 is the actual power of the secondary battery; SOC Base is the reference power of the secondary battery; 额定 is the rated power of the secondary battery; ɑ is a weight factor, wherein ɑ is greater than 0.

4. The method according to claim 1, characterized in that: Each parallel-connected fuel cell has a corresponding optimal power range; as well as, The method further comprises: The intersection between the optimal power intervals corresponding to the fuel cells connected in parallel is determined, and the intersection is determined as the target power interval.

5. The method according to claim 1, characterized in that: Each parallel-connected fuel cell has a corresponding optimal power range; as well as, The method further comprises: The optimal power interval corresponding to any fuel cell is determined as the target power interval.

6. The method according to claim 1, characterized in that The target power range is specifically greater than or equal to Pmin and less than or equal to Pmax; and, According to the total required power and the target power range, the number of fuel cells M to be called is determined, specifically including: According to the total required power, Pmin and Pmax, the evaluation parameters Nmin, Nmax, Lmin and Lmax are calculated; wherein Nmin is the integer ratio of the total required power to Pmin, Nmax is the integer ratio of the total required power to Pmax, Lmin is the remainder of the ratio of the total required power to Pmin, and Lmax is the remainder of the ratio of the total required power to Pmin; If Nmin is equal to 0, the value of M is 1; When Nmin is not equal to 0, if Nmax is greater than N, the value of M is N; When Nmin is greater than 0 and Nmax is less than or equal to N, if Lmin is equal to 0, the value of M can be Nmin; When Nmin is greater than 0, Nmax is less than or equal to N, and Lmin is not equal to 0, if Lmax is equal to 0, the value of M can be Nmax; When Nmin is greater than 0, Nmax is less than or equal to N, Lmin is not equal to 0, and Lmax is not equal to 0, the value of M can be Nmin.

7. The method according to claim 1, characterized in that In the process where the selected M fuel cells each supply power to the outside with the power generation power P, if it is monitored that the M fuel cells include a faulty fuel cell, the method further includes: restarting the faulty fuel cell.

8. The method according to claim 7, characterized in that If the faulty fuel cell still has a fault after restarting, the method further includes: The power generation power P of the fuel cell that is still faulty after restarting is evenly distributed to the other fuel cells in the M fuel cells.

9. A controller, characterized in that: The controller distributes the power generation of N parallel-connected fuel cells in the fuel cell system using the method described in any one of claims 1 to 8, wherein the fuel cell system includes a secondary battery and N parallel-connected fuel cells.

10. A fuel cell system, characterized in that: The fuel cell system comprises a secondary battery, N fuel cells connected in parallel, and the controller as claimed in claim 9.

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