A power distribution method and device for a fuel cell hybrid power system

Abstract

This application provides a power distribution method and apparatus for a fuel cell hybrid power system. At the start time of the i-th maintenance duration, the i-th initial target power of the fuel cell is obtained. The i-th initial target power is determined based on the vehicle's total power demand before the start time and the first charge state of the high-voltage battery before the start time. If the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is greater than or equal to the power step size, then the i-th actual target power of the fuel cell is determined based on the historical target power within the (i-1)-th maintenance duration and the power step size. If the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is less than the power step size, the historical target power within the (i-1)-th maintenance duration is determined as the i-th actual target power of the fuel cell. Controlling the stepwise change of the actual target power can match the power consumption response rate of the fuel cell.

Description

Technical Field

[0001] This application relates to the field of vehicles, and in particular to a power distribution method and apparatus for a fuel cell hybrid power system. Background Technology

[0002] Because fuel cell hybrid vehicles are in the early stages of industrialization, the energy management strategies for them either follow the mature strategies of internal combustion engine hybrid systems or adopt ideal strategies based on energy-optimal calculations. The former has the advantage of being proven in mature products and having low application risk; however, the power response rate of fuel cell systems is generally 30kW / s, far lower than that of internal combustion engines. Therefore, directly adopting traditional hybrid strategies will cause the fuel cell system to fail to follow the target power curve and cannot meet control precision requirements. The latter ensures optimal system efficiency, but often cannot be applied to real-time embedded systems due to chip computing power or storage limitations, making productization difficult. Therefore, providing a suitable power distribution method for fuel cell hybrid systems has become an urgent technical problem to be solved. Summary of the Invention

[0003] In view of this, the purpose of this application is to provide a power distribution method and apparatus for a fuel cell hybrid power system, which controls the stepwise change of the actual target power of the fuel cell, matches the power consumption response rate of the fuel cell, and enables the actual output power of the fuel cell hybrid power system to follow the actual target power change, thereby improving system efficiency and operational stability. The specific scheme is as follows:

[0004] In a first aspect, this application provides a power distribution method for a fuel cell hybrid power system, including:

[0005] At the start time node of the i-th maintenance duration, the i-th initial target power of the fuel cell is obtained; the i-th initial target power is determined based on the vehicle's total power demand before the start time node and the first charge state of the high-voltage battery before the start time node.

[0006] If the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is greater than or equal to the power step size, then the i-th actual target power of the fuel cell is determined based on the historical target power within the (i-1)-th maintenance duration and the power step size; where i is a positive integer, and when i is 1, the historical target power within the (i-1)-th maintenance duration is equal to the i-th initial target power;

[0007] If the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is less than the power step size, the historical target power within the (i-1)-th maintenance duration is determined as the i-th actual target power of the fuel cell;

[0008] Using the i-th actual target power, the actual output power of the fuel cell is controlled within the i-th maintenance duration.

[0009] Optionally, if the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is greater than or equal to the power step size, then determining the i-th actual target power of the fuel cell based on the historical target power within the (i-1)-th maintenance duration and the power step size includes:

[0010] If the i-th initial target power is greater than or equal to the sum of the historical target power and the power step size within the (i-1)-th maintenance duration, then the sum of the historical target power and the power step size within the (i-1)-th maintenance duration is determined as the i-th actual target power;

[0011] If the i-th initial target power is less than or equal to the difference between the historical target power and the power step size within the (i-1)-th maintenance duration, then the difference between the historical target power and the power step size within the (i-1)-th maintenance duration is determined as the i-th actual target power.

[0012] Optionally, the method further includes:

[0013] Obtain the switching time of the fuel cell from the historical target power during the (i-1)th maintenance period to the ith actual target power;

[0014] The duration of the i-th maintenance period is adjusted according to the switching duration.

[0015] Optionally, obtaining the i-th initial target power of the fuel cell includes:

[0016] At the start time of the (i-1)th maintenance duration, obtain the vehicle's total power demand and the first state of charge of the high-voltage battery;

[0017] Determine multiple operating points within the (i-1)th maintenance duration;

[0018] At each operating point, the first instantaneous output power of the fuel cell is obtained, and the second instantaneous output power of the high-voltage battery is calculated based on the first instantaneous output power and the power demand of the vehicle.

[0019] Determine the equivalent factor corresponding to the (i-1)th maintenance duration based on the first charge state;

[0020] At each operating point, the equivalent hydrogen consumption at each operating point is obtained based on the equivalent factor, the second instantaneous output power, and the equivalent fuel consumption minimization strategy.

[0021] The minimum value among the equivalent hydrogen consumption at each operating point is determined as the target equivalent hydrogen consumption, and the first instantaneous output power corresponding to the operating point where the target equivalent hydrogen consumption is located is determined as the i-th initial target power of the fuel cell.

[0022] Optionally, determining the equivalent factor corresponding to the (i-1)th maintenance duration based on the first charge state includes:

[0023] Based on the highest and lowest permissible charge of the high-voltage battery, the first charge state is normalized to obtain the second charge state;

[0024] The third charge state is obtained by summing the second charge state and the normalized charge states within each maintenance duration before the (i-1)th maintenance duration.

[0025] The equivalent factor corresponding to the (i-1)th maintenance duration is determined based on the second charge state and the third charge state.

[0026] Optionally, the second charge state is determined using the following formula:

[0027]

[0028] Wherein, the SOC i-1 For the first charge state during the (i-1)th maintenance duration, the X i-1 For the second charge state during the (i-1)th maintenance period, SOCH is the highest permissible charge, and SOCL is the lowest permissible charge;

[0029] The equivalent factor is determined by the following formula:

[0030]

[0031] Wherein, the s i-1 X is the equivalent factor corresponding to the (i-1)th maintenance duration. i-1 For the second charge state during the (i-1)th maintenance duration, the I i-1 The sum of the second charge state and the normalized charge states within each maintenance duration preceding the (i-1)th maintenance duration, wherein I i-1 The value range is [-25, 25].

[0032] Secondly, embodiments of this application also provide a power distribution device for a fuel cell hybrid power system, comprising:

[0033] The first acquisition unit is used to acquire the i-th initial target power of the fuel cell at the start time node of the i-th maintenance duration; the i-th initial target power is determined based on the vehicle's total power demand before the start time node and the first charge state of the high-voltage battery before the start time node.

[0034] The first determining unit is configured to determine the i-th actual target power of the fuel cell based on the historical target power within the (i-1)-th maintenance duration and the power step size if the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is greater than or equal to the power step size; where i is a positive integer, and when i is 1, the historical target power within the (i-1)-th maintenance duration is equal to the i-th initial target power;

[0035] The second determining unit is used to determine the historical target power within the (i-1)th maintenance time as the i-th actual target power of the fuel cell if the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)th maintenance time is less than the power step size.

[0036] A control unit is configured to control the actual output power of the fuel cell during the i-th maintenance duration using the i-th actual target power.

[0037] Optionally, the first determining unit is configured to determine the sum of the historical target power and the power step size within the (i-1)th maintenance duration as the i-th actual target power if the i-th initial target power is greater than or equal to the sum of the historical target power and the power step size within the (i-1)th maintenance duration.

[0038] If the i-th initial target power is less than or equal to the difference between the historical target power and the power step size within the (i-1)-th maintenance duration, then the difference between the historical target power and the power step size within the (i-1)-th maintenance duration is determined as the i-th actual target power.

[0039] Optionally, the device further includes:

[0040] The second acquisition unit is used to acquire the switching time of the fuel cell from the historical target power within the (i-1)th maintenance duration to the i-th actual target power;

[0041] An adjustment unit is used to adjust the i-th maintenance duration according to the switching duration.

[0042] Optionally, the first acquisition unit is used to acquire the vehicle's total power demand and the first state of charge of the high-voltage battery at the start time node of the (i-1)th maintenance duration.

[0043] Determine multiple operating points within the (i-1)th maintenance duration;

[0044] At each operating point, the first instantaneous output power of the fuel cell is obtained, and the second instantaneous output power of the high-voltage battery is calculated based on the first instantaneous output power and the power demand of the vehicle.

[0045] Determine the equivalent factor corresponding to the (i-1)th maintenance duration based on the first charge state;

[0046] At each operating point, the equivalent hydrogen consumption at each operating point is obtained based on the equivalent factor, the second instantaneous output power, and the equivalent fuel consumption minimization strategy.

[0047] The minimum value among the equivalent hydrogen consumption at each operating point is determined as the target equivalent hydrogen consumption, and the first instantaneous output power corresponding to the operating point where the target equivalent hydrogen consumption is located is determined as the i-th initial target power of the fuel cell.

[0048] This application provides a power distribution method and apparatus for a fuel cell hybrid power system. At the start time of the i-th maintenance duration, the i-th initial target power of the fuel cell is obtained. The i-th initial target power is determined based on the vehicle's total power demand before the start time and the first charge state of the high-voltage battery before the start time. If the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is greater than or equal to the power step size, then the i-th actual target power of the fuel cell is determined based on the historical target power within the (i-1)-th maintenance duration and the power step size. i is a positive integer; when i is 1, the historical target power within the (i-1)-th maintenance duration is equal to the i-th initial target power. If the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is less than the power step size, the historical target power within the (i-1)-th maintenance duration is determined as the i-th actual target power of the fuel cell. Using the i-th actual target power, the actual output power of the fuel cell is controlled within the i-th maintenance duration.

[0049] As can be seen, in this embodiment, the initial target power of the fuel cell for the current maintenance duration can be determined based on the charge state of the high-voltage battery. This improves the accuracy of the initial target power. Then, the difference between the initial target power for the current maintenance duration and the historical target power for the previous maintenance duration is compared with the power step size to determine the actual target power for the current maintenance duration, thereby controlling the actual output power of the fuel cell. In this way, the actual target power of the fuel cell can be controlled to change in a stepwise manner, matching the power consumption response rate of the fuel cell, so that the actual output power of the fuel cell hybrid power system can follow the changes in the actual target power, improving system efficiency and operational stability. Attached Figure Description

[0050] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0051] Figure 1 A schematic diagram of a fuel cell hybrid power system provided in an embodiment of this application is shown;

[0052] Figure 2 A schematic flowchart of a power distribution method for a fuel cell hybrid power system provided in an embodiment of this application is shown;

[0053] Figure 3 A schematic flowchart illustrating the process of determining the initial target power of a fuel cell, as provided in an embodiment of this application;

[0054] Figure 4 This is a structural block diagram of a power distribution device for a fuel cell hybrid power system provided in an embodiment of this application. Detailed Implementation

[0055] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0056] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0057] Based on the above technical problems, this application provides a power distribution method and apparatus for a fuel cell hybrid power system. At the start time of the i-th maintenance duration, the i-th initial target power of the fuel cell is obtained. The i-th initial target power is determined based on the vehicle's total power demand before the start time and the first charge state of the high-voltage battery before the start time. If the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is greater than or equal to the power step size, then the i-th actual target power of the fuel cell is determined based on the historical target power within the (i-1)-th maintenance duration and the power step size. i is a positive integer; when i is 1, the historical target power within the (i-1)-th maintenance duration is equal to the i-th initial target power. If the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is less than the power step size, the historical target power within the (i-1)-th maintenance duration is determined as the i-th actual target power of the fuel cell. Using the i-th actual target power, the actual output power of the fuel cell is controlled within the i-th maintenance duration.

[0058] As can be seen, in this embodiment, the initial target power of the fuel cell for the current maintenance duration can be determined based on the charge state of the high-voltage battery. This improves the accuracy of the initial target power. Then, the difference between the initial target power for the current maintenance duration and the historical target power for the previous maintenance duration is compared with the power step size to determine the actual target power for the current maintenance duration, thereby controlling the actual output power of the fuel cell. In this way, the actual target power of the fuel cell can be controlled to change in a stepwise manner, matching the power consumption response rate of the fuel cell, so that the actual output power of the fuel cell hybrid power system can follow the changes in the actual target power, improving system efficiency and operational stability.

[0059] For ease of understanding, the following detailed description, in conjunction with the accompanying drawings, provides a power distribution method and apparatus for a fuel cell hybrid power system according to an embodiment of this application.

[0060] refer to Figure 1The diagram shown is a structural schematic of a fuel cell hybrid power system provided in an embodiment of this application. It includes a fuel cell (Stack), a high-voltage battery, a motor, a front air conditioning compressor, a rear air conditioning compressor, a high-voltage inverter, a charging module, a high-to-low voltage conversion module, a low-voltage battery, low-voltage loads, and an electric heating module. The fuel cell serves as the energy output unit, the high-voltage battery as the energy storage unit, and the motor, high-voltage electrical appliances, and other low-voltage loads as energy consumption units. Energy is generated from the fuel cell, stored or released by the high-voltage battery, and consumed by the motor and other electrical appliances. The total demand of all energy consumption units can be defined as the vehicle's required power (PVeh, in kW). The state of charge (SOC, in %), maximum allowable charge (SOCH, in %), and minimum allowable charge (SOCL, in %) of the high-voltage battery are used as the system state and constraints of the energy storage unit. PVeh, SOC, SOCH, and SOCL are used as inputs to the control strategy, and the outputs are the target power of the fuel cell (PFcsTar, in kW) and the target power of the high-voltage battery (PBatTar, in kW).

[0061] refer to Figure 2 The diagram shown is a flowchart illustrating a power distribution method for a fuel cell hybrid power system provided in an embodiment of this application. The method may include the following steps.

[0062] S101, at the start time node of the i-th maintenance duration, obtain the i-th initial target power of the fuel cell.

[0063] In this embodiment of the application, the maintenance duration is the duration during which the fuel cell maintains a set power. The i-th initial target power of the fuel cell can be obtained at the start time node of the i-th maintenance duration. The i-th initial target power is determined based on the vehicle's total power demand before the start time node and the first charge state of the high-voltage battery before the start time node, where i is a positive integer.

[0064] For example, at the start of the second maintenance period, the second initial target power of the fuel cell is acquired. This second initial target power is determined based on the vehicle's overall power demand and the first state of charge of the high-voltage battery. The vehicle's overall power demand and the first state of charge are collected before the start of the second maintenance period, with the first state of charge being the collected state of charge of the high-voltage battery. In this way, determining the initial target power of the fuel cell based on the state of charge of the high-voltage battery improves the accuracy of the initial target power, thereby improving the accuracy of the actual target power. This allows the actual output power of the fuel cell hybrid system to follow changes in the actual target power, improving system efficiency and operational stability.

[0065] In this embodiment of the application, obtaining the i-th initial target power of the fuel cell may include: at the start time node of the (i-1)-th maintenance duration, obtaining the vehicle's total power demand and the first charge state of the high-voltage battery. Specifically, at the start time node of the (i-1)-th maintenance duration, i.e. the previous stable duration, the vehicle's total power demand and the charge state of the high-voltage battery may be obtained; and determining multiple operating points within the (i-1)-th maintenance duration, which may be denoted as j, for example, 10.

[0066] Next, at each operating point, the first instantaneous output power of the fuel cell is obtained, and the second instantaneous output power of the high-voltage battery is calculated based on the first instantaneous output power and the power demand of the vehicle. The power demand of the vehicle is jointly provided by the output power of the high-voltage battery and the output power of the fuel cell. Therefore, the instantaneous output power of the high-voltage battery can be the difference between the power demand of the vehicle and the instantaneous output power of the fuel cell.

[0067] Then, the equivalent factor corresponding to the (i-1)th maintenance duration is determined based on the first charge state. In this way, the equivalent factor is determined based on the charge state of the high-voltage battery. Compared with the prior art, where the equivalent factor is a fixed value, which can only meet the control requirements under specific operating conditions, in this application, the equivalent factor is variable in different decision cycles, which can meet the requirements of various operating conditions.

[0068] In this embodiment of the application, determining the equivalent factor corresponding to the (i-1)th maintenance duration based on the first charge state includes: normalizing the first charge state based on the highest and lowest allowable charge of the high-voltage battery to obtain a second charge state; summing the second charge state and the normalized charge states within each maintenance duration before the (i-1)th maintenance duration to obtain a third charge state; and determining the equivalent factor corresponding to the (i-1)th maintenance duration based on the second charge state and the third charge state.

[0069] Specifically, penalty factors related to SOC, namely SOC, SOCH, and SOCL, can be added to the equivalent factor to enable it to cope with more random vehicle operating conditions and improve the accuracy of the initial target power. The specific implementation involves normalizing the SOC to obtain the second charge state, which is determined using the following formula:

[0070]

[0071] Wherein, the SOC i-1 For the first charge state during the (i-1)th maintenance duration, the X i-1 For the second charge state during the (i-1)th maintenance period, SOCH is the highest permissible charge and SOCL is the lowest permissible charge.

[0072] Then, the second charge state and the normalized charge states for all durations prior to the (i-1)th duration are integrated and summed, i.e., X is defined as follows: i-1 The cumulative value is the third charge state I i-1 The I i-1 The value range is [-25, 25], and the third charge state I i-1 It can be expressed as follows:

[0073]

[0074] Next, the equivalence factor is determined using the following formula:

[0075]

[0076] Wherein, the s i-1 X is the equivalent factor corresponding to the (i-1)th maintenance duration. i-1 For the second charge state during the (i-1)th maintenance duration, the I i-1 The third charge state is the sum of the normalized charge states of the second charge state and the various maintenance durations preceding the (i-1)th maintenance duration.

[0077] At each operating point, the equivalent hydrogen consumption for each operating point is obtained based on the equivalent factor, the second instantaneous output power, and the strategy of minimizing equivalent fuel consumption.

[0078] Specifically, the Equivalent Fuel Consumption Minimum Strategy (ECMS) is an instantaneous optimal energy management strategy proposed by Paganelli et al. This method is derived from the Pontryagin Minimum Principle (PMP), which calculates and minimizes the total equivalent fuel consumption of the hybrid vehicle to solve for the instantaneous optimal control strategy. The expression for the ECMS energy management strategy is as follows:

[0079]

[0080] in, For equivalent hydrogen consumption, For actual hydrogen consumption, Q lhv The low calorific value (Q) of hydrogen fuel lhv (≈113kJ / g), where s is called the equivalence factor, representing the conversion relationship between the electrical energy consumed / replenished by the battery and the hydrogen consumption.

[0081] Specifically, the larger s is, the closer the SOC is to SOCL, and the higher the instantaneous output power P of the high-voltage battery. batt right The greater the influence of s, the more the strategy favors fuel cell output; conversely, the smaller s is, the closer the SOC is to SOCH, and the more P batt right The smaller the impact, the more the strategy favors high-voltage battery output.

[0082] The minimum value among the equivalent hydrogen consumption at each operating point is determined as the target equivalent hydrogen consumption, and the first instantaneous output power corresponding to the operating point where the target equivalent hydrogen consumption is located is determined as the i-th initial target power of the fuel cell. Specifically, the equivalent hydrogen consumption of j operating points is compared, and the minimum value among them is taken as the target equivalent hydrogen consumption, and the instantaneous output power of the fuel cell corresponding to the operating point is taken as the initial target power of the fuel cell.

[0083] Specifically, refer to Figure 3 The diagram illustrates a process for determining the initial target power of a fuel cell according to an embodiment of this application. Within a decision cycle, the vehicle's total power demand (PVeh) and the state of charge (SOC) of the high-voltage battery are first obtained. Then, at each operating point, the first instantaneous output power PFcs(j) of the fuel cell is obtained, and the corresponding second instantaneous power PBatt(j) of the high-voltage battery is calculated. Next, the second state of charge Xsoc(i) and the third state of charge Isoc(i) are determined, and the equivalent factor s(i) is determined. The equivalent factor is the same for multiple operating points within a decision cycle. Finally, the equivalent hydrogen consumption is determined. The loop terminates when j ≥ N(PFcs), for example, when N is 10. The equivalent hydrogen consumption at j operating points is compared, and the minimum value is taken as the target equivalent hydrogen consumption. Then the initial target power PFcsIni of the fuel cell was determined.

[0084] S102, if the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is greater than or equal to the power step size, then the i-th actual target power of the fuel cell is determined based on the historical target power within the (i-1)-th maintenance duration and the power step size.

[0085] In this embodiment, a stepped target power variation strategy can be formulated to address the slow power response of fuel cells. This involves two important parameters: power step size and settling time. The power step size represents the amount of change in target power at each step, which is a calibrated value adjusted based on the dynamic response capability of the fuel cell. The settling time represents the time (T) maintained at the target power. stab ).

[0086] The stabilization time includes the intake response time (T). re System power change time (T) diff ) and default settling time (T) def ), and T stab =T re +T diff +Tdef Among them, T re Determined by the physical characteristics of the system; T def The power difference before and after the load change is 18.3. Within a decision cycle, if the cumulative time T... accu ≥T stab If the stable duration ends, then the condition is considered to have ended.

[0087] T diff The power difference before and after the load change is divided by the system response rate. The power difference before and after the load change is the difference between the i-th actual target power and the (i-1)-th actual target power. If it is determined that the output power of the fuel cell has reached the set actual target power ahead of schedule, this part of the time ends early. Therefore, the method also includes: obtaining the switching time of the fuel cell from the historical target power within the (i-1)-th maintenance duration to the i-th actual target power, and adjusting the i-th maintenance duration according to the switching time. The switching time is the system power change time T. diff For example, if the set switching time is 0.25s, but the actual switching time during operation is 0.2s, then the switching time is determined to be 0.2s, thereby shortening the stabilization time.

[0088] In this embodiment, if the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is greater than or equal to the power step size, then the i-th actual target power of the fuel cell is determined based on the historical target power within the (i-1)-th maintenance duration and the power step size. The difference between the initial target power of this maintenance duration and the historical target power of the previous maintenance duration is compared with the power step size to determine the actual target power of this maintenance duration, thereby controlling the actual output power of the fuel cell.

[0089] This allows for controlled, step-wise changes in the actual target power of the fuel cell, matching the fuel cell's power consumption response rate. This ensures the actual output power of the fuel cell hybrid power system follows the changes in the actual target power, improving system efficiency and operational stability. It is understood that when i is 1, the historical target power within the (i-1)th maintenance duration is equal to the i-th initial target power.

[0090] Specifically, the step of determining the i-th actual target power of the fuel cell based on the historical target power within the (i-1)-th maintenance duration and the power step if the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is greater than or equal to the power step size includes: if the i-th initial target power is greater than or equal to the sum of the historical target power within the (i-1)-th maintenance duration and the power step size, then the sum of the historical target power within the (i-1)-th maintenance duration and the power step size is determined as the i-th actual target power; if the i-th initial target power is less than or equal to the difference between the historical target power within the (i-1)-th maintenance duration and the power step size, then the difference between the historical target power within the (i-1)-th maintenance duration and the power step size is determined as the i-th actual target power.

[0091] S103, if the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is less than the power step size, the historical target power within the (i-1)-th maintenance duration is determined as the i-th actual target power of the fuel cell.

[0092] Specifically, if the i-th initial target power is less than the sum of the historical target power and the power step size within the (i-1)-th maintenance duration, and less than the difference between the historical target power and the power step size within the (i-1)-th maintenance duration, then the historical target power within the (i-1)-th maintenance duration is determined as the i-th actual target power.

[0093] Specifically, after the (i-1)th maintenance period ends, if the i-th initial target power PFcsIni is greater than or equal to the sum of the (i-1)th historical target power and the power step size, then PFcsTar is determined to be equal to the sum of the (i-1)th historical target power and the power step size. If the i-th initial target power PFcsIni is less than or equal to the difference between the (i-1)th historical target power and the power step size, then PFcsTar is determined to be equal to the difference between the (i-1)th historical target power and the power step size. Otherwise, PFcsTar is determined to be equal to the (i-1)th historical target power.

[0094] S104, using the i-th actual target power, control the actual output power of the fuel cell during the i-th maintenance duration.

[0095] In the embodiments of this application, the actual target power of the fuel cell can be controlled to change in a stepwise manner, and the power consumption response rate of the fuel cell can be matched, so that the actual output power of the fuel cell hybrid power system can follow the actual target power change, thereby improving system efficiency and operational stability.

[0096] This application provides a power allocation method for a fuel cell hybrid power system. At the start time of the i-th maintenance duration, the i-th initial target power of the fuel cell is obtained. The i-th initial target power is determined based on the vehicle's total power demand before the start time and the first charge state of the high-voltage battery before the start time. If the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is greater than or equal to the power step size, then the i-th actual target power of the fuel cell is determined based on the historical target power within the (i-1)-th maintenance duration and the power step size. Here, i is a positive integer; when i is 1, the historical target power within the (i-1)-th maintenance duration is equal to the i-th initial target power. If the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is less than the power step size, the historical target power within the (i-1)-th maintenance duration is determined as the i-th actual target power of the fuel cell. Using the i-th actual target power, the actual output power of the fuel cell is controlled within the i-th maintenance duration.

[0097] As can be seen, in this embodiment, the initial target power of the fuel cell for the current maintenance duration can be determined based on the charge state of the high-voltage battery. This improves the accuracy of the initial target power. Then, the difference between the initial target power for the current maintenance duration and the historical target power for the previous maintenance duration is compared with the power step size to determine the actual target power for the current maintenance duration, thereby controlling the actual output power of the fuel cell. In this way, the actual target power of the fuel cell can be controlled to change in a stepwise manner, matching the power consumption response rate of the fuel cell, so that the actual output power of the fuel cell hybrid power system can follow the changes in the actual target power, improving system efficiency and operational stability.

[0098] Based on the above power distribution method for fuel cell hybrid power systems, this application also provides a power distribution device for fuel cell hybrid power systems, referencing... Figure 4 The diagram shown is a structural block diagram of a power distribution device for a fuel cell hybrid power system according to an embodiment of this application. The device may include:

[0099] The first acquisition unit 100 is used to acquire the i-th initial target power of the fuel cell at the start time node of the i-th maintenance duration; the i-th initial target power is determined based on the vehicle's total power demand before the start time node and the first charge state of the high-voltage battery before the start time node.

[0100] The first determining unit 200 is configured to determine the i-th actual target power of the fuel cell based on the historical target power within the (i-1)-th maintenance duration and the power step size if the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is greater than or equal to the power step size; where i is a positive integer, and when i is 1, the historical target power within the (i-1)-th maintenance duration is equal to the i-th initial target power;

[0101] The second determining unit 300 is used to determine the historical target power within the (i-1)th maintenance time as the i-th actual target power of the fuel cell if the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)th maintenance time is less than the power step size.

[0102] Control unit 400 is used to control the actual output power of the fuel cell during the i-th maintenance duration using the i-th actual target power.

[0103] Optionally, the first determining unit is configured to determine the sum of the historical target power and the power step size within the (i-1)th maintenance duration as the i-th actual target power if the i-th initial target power is greater than or equal to the sum of the historical target power and the power step size within the (i-1)th maintenance duration.

[0104] If the i-th initial target power is less than or equal to the difference between the historical target power and the power step size within the (i-1)-th maintenance duration, then the difference between the historical target power and the power step size within the (i-1)-th maintenance duration is determined as the i-th actual target power.

[0105] Optionally, the device further includes:

[0106] The second acquisition unit is used to acquire the switching time of the fuel cell from the historical target power within the (i-1)th maintenance duration to the i-th actual target power;

[0107] An adjustment unit is used to adjust the i-th maintenance duration according to the switching duration.

[0108] Optionally, the first acquisition unit is used to acquire the vehicle's total power demand and the first state of charge of the high-voltage battery at the start time node of the (i-1)th maintenance duration.

[0109] Determine multiple operating points within the (i-1)th maintenance duration;

[0110] At each operating point, the first instantaneous output power of the fuel cell is obtained, and the second instantaneous output power of the high-voltage battery is calculated based on the first instantaneous output power and the power demand of the vehicle.

[0111] Determine the equivalent factor corresponding to the (i-1)th maintenance duration based on the first charge state;

[0112] At each operating point, the equivalent hydrogen consumption at each operating point is obtained based on the equivalent factor, the second instantaneous output power, and the equivalent fuel consumption minimization strategy.

[0113] The minimum value among the equivalent hydrogen consumption at each operating point is determined as the target equivalent hydrogen consumption, and the first instantaneous output power corresponding to the operating point where the target equivalent hydrogen consumption is located is determined as the i-th initial target power of the fuel cell.

[0114] This application provides a power distribution device for a fuel cell hybrid power system. A first acquisition unit is configured to acquire the i-th initial target power of the fuel cell at the start time node of the i-th maintenance duration. The i-th initial target power is determined based on the vehicle's total power demand before the start time node and the first charge state of the high-voltage battery before the start time node. A first determination unit is configured to, if the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is greater than or equal to the power step size, then determine the power distribution based on the historical target power within the (i-1)-th maintenance duration and the... The power step size determines the i-th actual target power of the fuel cell; i is a positive integer, and when i is 1, the historical target power within the (i-1)-th maintenance duration is equal to the i-th initial target power; the second determining unit is used to determine the historical target power within the (i-1)-th maintenance duration as the i-th actual target power of the fuel cell if the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is less than the power step size; the control unit is used to control the actual output power of the fuel cell within the i-th maintenance duration using the i-th actual target power.

[0115] As can be seen, in this embodiment, the initial target power of the fuel cell for the current maintenance duration can be determined based on the charge state of the high-voltage battery. This improves the accuracy of the initial target power. Then, the difference between the initial target power for the current maintenance duration and the historical target power for the previous maintenance duration is compared with the power step size to determine the actual target power for the current maintenance duration, thereby controlling the actual output power of the fuel cell. In this way, the actual target power of the fuel cell can be controlled to change in a stepwise manner, matching the power consumption response rate of the fuel cell, so that the actual output power of the fuel cell hybrid power system can follow the changes in the actual target power, improving system efficiency and operational stability.

[0116] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on its differences from other embodiments. In particular, the apparatus embodiments are basically similar to the method embodiments, so they are described more simply; relevant parts can be referred to the descriptions of the method embodiments.

[0117] The above description is merely a preferred embodiment of this application. Although this application has disclosed preferred embodiments above, it is not intended to limit this application. Any person skilled in the art can make many possible variations and modifications to the technical solutions of this application using the methods and techniques disclosed above, or modify them into equivalent embodiments with equivalent changes, without departing from the scope of the technical solutions of this application. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this application without departing from the content of the technical solutions of this application shall still fall within the protection scope of the technical solutions of this application.

Claims

1. A power distribution method for a fuel cell hybrid power system, characterized in that, include: At the start time of the i-th maintenance duration, obtain the i-th initial target power of the fuel cell; The i-th initial target power is determined based on the vehicle's total power requirement before the start time node and the first charge state of the high-voltage battery before the start time node. If the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is greater than or equal to the power step size, then the i-th actual target power of the fuel cell is determined based on the historical target power within the (i-1)-th maintenance duration and the power step size; where i is a positive integer, and when i is 1, the historical target power within the (i-1)-th maintenance duration is equal to the i-th initial target power; If the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is less than the power step size, the historical target power within the (i-1)-th maintenance duration is determined as the i-th actual target power of the fuel cell; Using the i-th actual target power, the actual output power of the fuel cell is controlled within the i-th maintenance duration.

2. The method according to claim 1, characterized in that, If the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is greater than or equal to the power step size, then determining the i-th actual target power of the fuel cell based on the historical target power within the (i-1)-th maintenance duration and the power step size includes: If the i-th initial target power is greater than or equal to the sum of the historical target power and the power step size within the (i-1)-th maintenance duration, then the sum of the historical target power and the power step size within the (i-1)-th maintenance duration is determined as the i-th actual target power; If the i-th initial target power is less than or equal to the difference between the historical target power and the power step size within the (i-1)-th maintenance duration, then the difference between the historical target power and the power step size within the (i-1)-th maintenance duration is determined as the i-th actual target power.

3. The method according to claim 1, characterized in that, The method further includes: Obtain the switching time of the fuel cell from the historical target power during the (i-1)th maintenance period to the ith actual target power; The duration of the i-th maintenance period is adjusted according to the switching duration.

4. The method according to claim 1, characterized in that, Obtaining the i-th initial target power of the fuel cell includes: At the start time of the (i-1)th maintenance duration, obtain the vehicle's total power demand and the first state of charge of the high-voltage battery; Determine multiple operating points within the (i-1)th maintenance duration; At each operating point, the first instantaneous output power of the fuel cell is obtained, and the second instantaneous output power of the high-voltage battery is calculated based on the first instantaneous output power and the power demand of the vehicle. Determine the equivalent factor corresponding to the (i-1)th maintenance duration based on the first charge state; At each operating point, the equivalent hydrogen consumption at each operating point is obtained based on the equivalent factor, the second instantaneous output power, and the equivalent fuel consumption minimization strategy. The minimum value among the equivalent hydrogen consumption at each operating point is determined as the target equivalent hydrogen consumption, and the first instantaneous output power corresponding to the operating point where the target equivalent hydrogen consumption is located is determined as the i-th initial target power of the fuel cell.

5. The method according to claim 4, characterized in that, The step of determining the equivalent factor corresponding to the (i-1)th maintenance duration based on the first charge state includes: Based on the highest and lowest permissible charge of the high-voltage battery, the first charge state is normalized to obtain the second charge state; The third charge state is obtained by summing the second charge state and the normalized charge states within each maintenance duration before the (i-1)th maintenance duration. The equivalent factor corresponding to the (i-1)th maintenance duration is determined based on the second charge state and the third charge state.

6. The method according to claim 5, characterized in that, The second charge state is determined using the following formula: Wherein, the SOC i-1 For the first charge state during the (i-1)th maintenance duration, the X i-1 For the second charge state during the (i-1)th maintenance period, SOCH is the highest permissible charge, and SOCL is the lowest permissible charge; The equivalent factor is determined by the following formula: Wherein, the s i-1 X is the equivalent factor corresponding to the (i-1)th maintenance duration. i-1 For the second charge state during the (i-1)th maintenance duration, the I i-1 The sum of the second charge state and the normalized charge states within each maintenance duration preceding the (i-1)th maintenance duration, wherein I i-1 The value range is [-25, 25].

7. A power distribution device for a fuel cell hybrid power system, characterized in that, include: The first acquisition unit is used to acquire the i-th initial target power of the fuel cell at the start time node of the i-th maintenance duration; The i-th initial target power is determined based on the vehicle's total power requirement before the start time node and the first charge state of the high-voltage battery before the start time node. The first determining unit is configured to determine the i-th actual target power of the fuel cell based on the historical target power within the (i-1)-th maintenance duration and the power step size if the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)-th maintenance duration is greater than or equal to the power step size; where i is a positive integer, and when i is 1, the historical target power within the (i-1)-th maintenance duration is equal to the i-th initial target power; The second determining unit is used to determine the historical target power within the (i-1)th maintenance time as the i-th actual target power of the fuel cell if the absolute value of the difference between the i-th initial target power and the historical target power within the (i-1)th maintenance time is less than the power step size. A control unit is configured to control the actual output power of the fuel cell during the i-th maintenance duration using the i-th actual target power.

8. The apparatus according to claim 7, characterized in that, The first determining unit is configured to determine the sum of the historical target power and the power step size within the (i-1)th maintenance duration as the i-th actual target power if the i-th initial target power is greater than or equal to the sum of the historical target power and the power step size within the (i-1)th maintenance duration. If the i-th initial target power is less than or equal to the difference between the historical target power and the power step size within the (i-1)-th maintenance duration, then the difference between the historical target power and the power step size within the (i-1)-th maintenance duration is determined as the i-th actual target power.

9. The apparatus according to claim 7, characterized in that, The device further includes: The second acquisition unit is used to acquire the switching time of the fuel cell from the historical target power within the (i-1)th maintenance duration to the i-th actual target power; An adjustment unit is used to adjust the i-th maintenance duration according to the switching duration.

10. The apparatus according to claim 7, characterized in that, The first acquisition unit is used to acquire the vehicle's total power demand and the first state of charge of the high-voltage battery at the start time node of the (i-1)th maintenance duration. Determine multiple operating points within the (i-1)th maintenance duration; At each operating point, the first instantaneous output power of the fuel cell is obtained, and the second instantaneous output power of the high-voltage battery is calculated based on the first instantaneous output power and the power demand of the vehicle. Determine the equivalent factor corresponding to the (i-1)th maintenance duration based on the first charge state; At each operating point, the equivalent hydrogen consumption at each operating point is obtained based on the equivalent factor, the second instantaneous output power, and the equivalent fuel consumption minimization strategy. The minimum value among the equivalent hydrogen consumption at each operating point is determined as the target equivalent hydrogen consumption, and the first instantaneous output power corresponding to the operating point where the target equivalent hydrogen consumption is located is determined as the i-th initial target power of the fuel cell.

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