An energy distribution control method for a hydrogen fuel vehicle based on operation data

Abstract

The present invention discloses an energy distribution control method for a hydrogen fuel vehicle based on operation data. The power parameters of the vehicle's fuel cell and power battery are obtained based on the operation data of the vehicle, the SOC of the power battery is detected in real time, and the net output power of the fuel cell is determined based on the SOC of the power battery and the power parameters. According to the vehicle configuration, the present invention reduces the change in the output power of the fuel cell on the premise of ensuring the regenerative braking energy recovery of the whole vehicle, can operate in the high-efficiency area of the fuel cell to the greatest extent, not only ensures the economy of the whole vehicle, but also reduces the impact on the service life of the fuel cell due to frequent load changes; at the same time, it can prevent the occurrence of overcharging or over-discharging of the power battery and ensure the service life of the power battery system.

Description

Technical Field

[0001] The present invention belongs to the technical field of fuel cell vehicles, and in particular relates to an energy distribution control method for a hydrogen fuel vehicle based on operation data. Background Art

[0002] In recent years, the number of fuel cell vehicles has continued to increase, but due to the infrastructure limitations of hydrogen refueling stations, hydrogen fuel vehicles are currently only used in some typical working conditions or typical scenarios with relatively fixed routes, such as sanitation vehicles, buses, urban construction waste, municipal engineering, short-distance transportation in sites, short-distance transportation in mining areas, sand and gravel, short-distance transportation in logistics, steel mills, ports and other short-distance transportation.

[0003] At present, there are many factors that affect the performance of domestic hydrogen fuel cell system products, such as loading and unloading rates, lifespan, etc. In order to compensate for the slow power response of fuel cells, fuel cell vehicles with power batteries as auxiliary energy sources are designed. During operation, several typical power points of the fuel cell are selected to operate, and the corresponding fuel cell power output points are set according to the changes in the power battery SOC, thereby reducing the loading and unloading time and ensuring the service life of the fuel cell.

[0004] In order to ensure the optimal hydrogen consumption of the whole vehicle, the fuel cell power and the power of the power battery are reasonably allocated under the premise of ensuring the power demand of the whole vehicle, ensuring that the fuel cell operates in a high efficiency area and does not change load frequently, while maximizing the utilization rate of the vehicle's braking energy recovery.

[0005] The prior art (application publication number CN 114506250 A) discloses a fuel cell vehicle operating condition adaptive control method based on operating data, which divides the output power of the fuel cell into four power points based on the vehicle demand power, the power battery SOC, the average power demand of the vehicle under typical operating conditions in the operating data, and the power at the optimal point of the stack efficiency. The four power points are calibrated according to the actual operating data to avoid the shortcomings of frequent load changes in the output power of the fuel cell and operation in the low efficiency area.

[0006] This method does not take into account the load-changing effects of vehicle braking energy recovery and peak charging power limit of the power battery on the output power of the fuel cell; it does not take into account that at low SOC, frequent changes in the power demand of the vehicle will lead to frequent load changes in the output power of the fuel cell, thereby affecting the service life of the fuel cell. Summary of the invention

[0007] The purpose of the present invention is to address the deficiencies of the above-mentioned background technology and to provide an energy distribution control method for hydrogen fuel vehicles based on operating data, which can operate in the fuel cell high efficiency area to the maximum extent, thereby ensuring the economy of the entire vehicle and reducing the impact of frequent load changes on the life of the fuel cell.

[0008] The technical solution adopted by the present invention is: an energy distribution control method for a hydrogen fuel vehicle based on operation data, obtaining the power parameters of the vehicle's fuel cell and power battery based on the operation data of the vehicle,

[0009] real-time detecting the SOC of the power battery, and determining the net output power of the fuel cell based on the SOC of the power battery and the power parameters.

[0010] Further, when the SOC of the power battery is SOC≥SOC max , determining that the net output power P FC of the fuel cell is zero, and the SOC max is the upper limit value of the remaining power allowed for charging.

[0011] Further, when the SOC of the power battery is SOC<SOC min , determining that the net output power P FC of the fuel cell is P FC =P FC_rat , the SOC min is the lower limit value of the remaining power allowed for discharging, and PFC_rat is the rated power of the fuel cell.

[0012] Further, calibrating the first threshold SOC0, the second threshold SOC1, and the third threshold SOC2 of the remaining power of the power battery, and determining the net output power of the fuel cell according to the magnitude relationship between the SOC of the power battery and the first threshold, the second threshold, and the third threshold of the remaining power.

[0013] Further, the first threshold SOC0 of the remaining power is determined by the following formula:

[0014] SOC0=SOC min +(P veh_max *(T FC_min +T FC_rat )*100 / 60 / Q bat )

[0015] wherein, P veh_max is the maximum net output power of the fuel cell allowed for the whole vehicle, T FC_min is the shortest continuous operation time of the fuel cell power point, T FC_rat is the cold start time of the fuel cell at normal temperature rated power; Q bat is the rated capacity of the power battery, and SOC min is the lower limit value of the remaining power allowed for discharging.

[0016] Further, the second threshold SOC1 of the remaining power is determined by the following formula:

[0017] P bat_charge_max =P FC_eff +PFC_add +P mot_charge_max -P veh_FC_min

[0018] SOC1 = (P FC_eff +P FC_add -P veh_FC_min ) * (T FC_min +T FC_rat * (P FC_eff +P FC_add ) * 100 / 60 / Q bat )

[0019] Wherein, P bat_charge_max is the peak charging power of the power battery, P mot_charge_max is the maximum charging power of the vehicle's braking energy recovery, P FC_eff is the net output power point of the highest efficiency of the fuel cell, P FC_add is the fuel cell power compensation value; P veh_FC_min is the minimum power consumption of the vehicle when the fuel cell idles; T FC_min is the shortest continuous operation time of the fuel cell power point, T FC_rat is the cold start time of the fuel cell's normal rated power at room temperature; Q bat is the rated capacity of the power battery.

[0020] Furthermore, the third threshold SOC2 of the remaining power is determined by the following formula:

[0021] P bat_charge_max = P mot_charge_max +P FC_min -P veh_FC_min

[0022] Wherein, P bat_charge_max is the peak charging power of the power battery, P mot_charge_max is the maximum charging power of the vehicle's braking energy recovery, P FC_min is the idling power of the fuel cell, P veh_FC_min is the minimum power consumption of the vehicle when the fuel cell idles.

[0023] Furthermore, when the SOC of the power battery is SOC min ≤ SOC < SOC0, the net output power P FC of the fuel cell is determined to be P FC = P veh_max , and the P veh_max is the maximum net output power of the fuel cell allowed by the vehicle, and P veh_max takes the minimum value between the rated power P mot_rat of the main drive motor and the rated power P FC_rat of the fuel cell.

[0024] Further, when the SOC of the power battery satisfies SOC0 ≤ SOC < SOC1, determine the net output power P of the fuel cell FC as P FC =P FC_eff +P FC_add , where P FC_eff is the net output power point at the highest efficiency of the fuel cell, and P FC_add is the fuel cell power compensation value.

[0025] Further, when the SOC of the power battery satisfies SOC1 ≤ SOC < SOC2, determine the net output power P of the fuel cell FC as P FC =P FC_eff , where P FC_eff is the net output power point at the highest efficiency of the fuel cell.

[0026] Furthermore, when the SOC of the power battery satisfies SOC2 ≤ SOC < SOC max , determine the net output power P of the fuel cell FC as P FC =P veh_min ;

[0027] P veh_min =P FC_min -P veh_FC_min

[0028] where P veh_min is the minimum net output power of the fuel cell allowed for the vehicle, P FC_min is the idling power of the fuel cell, and P veh_FC_min is the minimum power consumption of the vehicle when the fuel cell outputs idling power. If P veh_min is less than the idling power P FC_min of the fuel cell, the net output power P FC of the fuel cell is P FC =0.

[0029] According to the vehicle configuration, the present invention reduces the change in the output power of the fuel cell on the premise of ensuring the regenerative braking energy recovery of the vehicle, can operate in the high-efficiency area of the fuel cell to the greatest extent, not only ensures the vehicle economy, but also reduces the impact on the fuel cell life due to frequent load changes; at the same time, it can prevent overcharging or over-discharging of the power battery and ensure the life of the power battery system. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is the control flow chart of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0031] The following further describes the specific embodiments of the present invention in conjunction with the accompanying drawings. It should be noted here that the description of these embodiments is used to help understand the present invention, but does not limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0032] As Figure 1 shown, the present invention provides an energy distribution control method for a hydrogen fuel cell vehicle based on operation data, obtains the power parameters of the vehicle's fuel cell and power battery based on the operation data of the vehicle, real-time detects the SOC of the power battery, and determines the net output power of the fuel cell based on the SOC of the power battery and the power parameters.

[0033] The above power parameters include the peak charging power P bat_charge_max of the power battery, the maximum charging power P mot_charge_max of the vehicle's regenerative braking energy recovery, the minimum allowable net output power P veh_min of the vehicle's fuel cell, the idle power P FC_min of the fuel cell, the net output power point P FC_eff at the highest efficiency of the fuel cell, the power compensation value P FC_add of the fuel cell, the rated power P FC_rat of the fuel cell, the shortest continuous operation time T FC_min of the fuel cell power point, the rated power Q bat of the power battery, and the rated power P mot_rat of the main drive motor.

[0034] The specific steps to determine the net output power of the fuel cell are as follows:

[0035] Step 1: When the SOC of the power battery is SOC ≥ SOC max , the fuel cell shuts down, that is, the net output power P FC of the fuel cell is zero.

[0036] Step 2: When the SOC of the power battery is SOC < SOC min , determine that the net output power P FC of the fuel cell is P FC = P FC_rat , where the SOC min is the lower limit value of the allowable discharge of the remaining power, and PFC_rat is the rated power of the fuel cell.

[0037] Step 3: Calibrate the first threshold SOC0, the second threshold SOC1, and the third threshold SOC2 of the remaining power of the power battery according to the above power parameters, where SOC0 < SOC1 < SOC2. When the SOC of the power battery min ≤ SOC < SOC0, determine the net output power P of the fuel cellFC is P FC = P veh_max , where the P veh_max is the maximum net output power of the fuel cell allowed for the whole vehicle, and P veh_max is between the rated power P mot_rat of the main drive motor and the rated power P FC_rat of the fuel cell, taking the minimum value between the two.

[0038] Step 4: When the SOC of the power battery is SOC0 ≤ SOC < SOC1, determine the net output power P FC of the fuel cell as P FC = P FC_eff + P FC_add , where the P FC_eff is the net output power point at the highest efficiency of the fuel cell, and P FC_add is the fuel cell power compensation value.

[0039] Step 5: When the SOC of the power battery is SOC1 ≤ SOC < SOC2, determine the net output power P FC of the fuel cell as P FC = P FC_eff , where the P FC_eff is the net output power point at the highest efficiency of the fuel cell.

[0040] Step 6: When the SOC of the power battery is SOC2 ≤ SOC < SOC max , determine the net output power P FC of the fuel cell as P FC = P veh_min ;

[0041] P veh_min = P FC_min - P veh_FC_min ;

[0042] The P veh_min is the minimum net output power of the fuel cell allowed for the whole vehicle, P FC_min is the idle power of the fuel cell, P veh_FC_min is the minimum power consumption of the whole vehicle when the fuel cell outputs idle power. If P veh_min is less than the idle power P FC_min of the fuel cell, the net output power P FC of the fuel cell is P FC = 0.

[0043] In the above Step 3, the first threshold SOC0 of the remaining power is determined by the following formula:

[0044] SOC0 = SOC min + (P veh_max * (T FC_min + TFC_rat ) * 100 / 60 / Q bat )。

[0045] Determine the second threshold of remaining battery capacity SOC1 through the following formula:

[0046] P bat_charge_max = P FC_eff + P FC_add + P mot_charge_max - P veh_FC_min

[0047] SOC1 = (P FC_eff + P FC_add - P veh_FC_min ) * (T FC_min + T FC_rat * (P FC_eff + P FC_add ) * 100 / 60 / Q bat )。

[0048] Calculate P bat_charge_max through the following formula, and then look up the third threshold of remaining battery capacity SOC2 in the calibrated [ambient temperature - power battery SOC - P bat_charge_max table,

[0049] P bat_charge_max = P mot_charge_max + P FC_min - P veh_FC_min 。

[0050] Calibrate the fuel cell power compensation value P FC_add according to the time proportion of each SOC interval in the actual operating conditions, to achieve the following effects: 1. Maximize the time proportion in the interval of SOC0 ≤ SOC < SOC2 under a typical operating condition cycle. 2. Maximize the time proportion of operation in the high-efficiency area of P FC_eff 。

[0051] Embodiment

[0052] Based on a developed hydrogen fuel vehicle, adjust the fuel cell output power point by testing the following data through actual operating conditions. Include the rated capacity Q bat of the power battery = 50 kwh, the operating range of the power battery SOC is 30% - 85%, where the power battery SOC min = 30%, the power battery SOC max = 85%, and the peak charging power P bat_charge_max of the power battery at 30% - 85% is shown in Table 1; the maximum charging power P mot_charge_max of the vehicle's regenerative braking energy recovery = 160 kW, and the minimum power consumption P veh_FC_min= 5kW, the idle power of the fuel cell P FC_min = 10kW, the net output power point at the highest efficiency of the fuel cell P FC_eff = 10kW, the rated power of the fuel cell P FC_rat = 95kW, the shortest continuous operation time T at the power point of the fuel cell FC_min = 1min, the cold start time T of the fuel cell at normal temperature and rated power FC_rat = 2min, the rated power of the main drive motor is 80kW.

[0053] Table 1 Peak output power of the power battery

[0054] SOC Charging peak power / kW @ 10 s, 25 °C 30％ 210.3 35％ 213.4 40％ 215.4 45％ 214.3 50％ 213.1 55％ 198.0 60％ 180.6 65％ 169.0 70％ 144.0 75％ 130.2 80％ 113.4 85％ 106.8

[0055] Step 1: When the SOC of the power battery ≥ 85%, the fuel cell shuts down.

[0056] Step 2: When the SOC of the power battery < 30%, P FC = 95kW.

[0057] Step 3: According to the rated power P of the main drive motor mot_rat = 80kW, the rated power P of the fuel cell FC_rat = 95kW, the shortest continuous operation time T at the power point of the fuel cell FC_min = 1min, the cold start time T of the fuel cell at normal temperature and rated power TFC_rat = 2min, the power battery capacity Q bat = 50kWh, the minimum allowable SOC of the power battery is 30%, calculate SOC0 = 30% + (80 * 3 * 100 / 60 / 50)% = 38%, confirm that when 30% ≤ SOC < 38% of the power battery, P FC = 80kW. At this power point P FC When the braking energy recovery is completed, the fuel cell needs to limit the power output.

[0058] Step 4: According to the relationship between the SOC of the power battery and the peak charging power P of the power battery bat_charge_max as shown in Table 1, the net output power point at the highest efficiency of the fuel cell P FC_eff = 10kW, the minimum power consumption of the whole vehicle when the fuel cell outputs idle power P veh_FC_min = 5kW, the maximum charging power of the whole vehicle during braking energy recovery P mot_charge_max = 160kW, the shortest continuous operation time T at the power point of the fuel cell FC_min = 1min, the cold start time T of the fuel cell at normal temperature and rated power TFC_rat = 2min, the rated power P of the fuel cell FC_rat = 95kW, calculate

[0059] SOC1 = 38% + (10 + P FC_add-5)*(1 + 2*(10 + P FC_add ) / 95)*100 / 60 / 50

[0060] P bat_charge_max = 10 + P FC_add + 160 - 5

[0061] According to Table 1, for the relationship between the SOC of the power battery and the peak charging power P of the power battery bat_charge_max calculate SOC1 = 46%, P FC_add = 48 kW. When 38% ≤ SOC < 46% for the power battery, P FC = 58 kW. At this power point P FC When the vehicle performs regenerative braking energy, there is no need to limit the regenerative braking energy recovery power.

[0062] Step 5: According to the relationship between the SOC of the power battery and the peak charging power P of the power battery bat_charge_max as shown in Table 1, the maximum efficiency net output power point P of the fuel cell FC_eff = 10 kW, the minimum power consumption of the vehicle when the fuel cell outputs idle power P veh_FC_min = 5 kW, the maximum charging power of the vehicle during regenerative braking energy recovery P mot_charge_max = 160 kW.

[0063] According to the formula: P bat_charge_max = 160 + 10 - 5

[0064] Calculate SOC2 = 66%. When 46% ≤ SOC < 66% for the power battery,

[0065] P FC = 10 kW. At this power point P FC When the vehicle performs regenerative braking energy, there is no need to limit the regenerative braking energy recovery power.

[0066] Step 6: The maximum efficiency net output power point P of the fuel cell FC_eff = 10 kW, the minimum power consumption of the vehicle when the fuel cell outputs idle power P veh_FC_min = 5 kW.

[0067] According to the formula P veh_min = 10 - 5

[0068] When 66% ≤ SOC < 85% for the power battery, since P veh_min is less than the idle power of the fuel cell, the fuel cell shuts down.

[0069] Step 7: According to the time proportion of each SOC interval in the actual operating conditions, continuously calibrate P FC_add , to achieve the following effects: 1. The time proportion of 38% ≤ SOC < 66% is not less than 95% under a typical operating condition cycle; 2. PFC_eff The operating time ratio in the high-efficiency area is not less than 65%.

[0070] It should be understood that the specific order or hierarchy of steps in the disclosure process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of the present disclosure. The appended method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0071] To make the description of the present disclosure more detailed and complete, the above provides an illustrative description of the embodiments and specific examples of the present invention; however, this is not the only form for implementing or using the specific examples of the present invention. The embodiments cover the features of multiple specific examples and the method steps and their sequences for constructing and operating these specific examples. However, other specific examples can also be used to achieve the same or equivalent functions and step sequences.

[0072] In the above detailed description, various features are combined in a single embodiment to simplify the present disclosure. This method of disclosure should not be construed as reflecting an intention that the embodiments of the claimed subject matter require more features than are clearly stated in each claim. On the contrary, as reflected in the appended claims, the present invention is in a state with fewer features than all the features of the disclosed single embodiment. Therefore, the appended claims are hereby clearly incorporated into the detailed description, where each claim stands alone as a separate preferred embodiment of the present invention.

[0073] To enable any person skilled in the art to implement or use the present invention, the above-described disclosed embodiments are described. For those skilled in the art; various modifications of these embodiments are obvious, and the general principles defined herein can also be applied to other embodiments without departing from the spirit and scope of the present disclosure. Therefore, the present disclosure is not limited to the embodiments given herein, but is consistent with the broadest scope of the principles and novel features disclosed in this application.

[0074] The above is only the specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed by the present invention should be covered within the scope of protection of the present invention. The content not described in detail in this specification belongs to the prior art well-known to those skilled in the art.

Claims

1. An energy distribution control method for a hydrogen fuel vehicle based on operation data, characterized in that: Obtain the power parameters of the vehicle's fuel cell and power battery based on the vehicle's operation data, Real-time detect the power battery SOC, and determine the net output power of the fuel cell based on the power battery SOC and power parameters; Calibrate the first threshold SOC0 of the remaining power of the power battery, the second threshold SOC1 of the remaining power, and the third threshold SOC2 of the remaining power. According to the magnitude relationship between the power battery SOC and the first threshold, the second threshold, and the third threshold of the remaining power, determine the net output power of the fuel cell; Determine the first threshold SOC0 of the remaining power through the following formula SOC0 = SOC min +(P veh_max *(T FC_min +T FC_rat )*100 / 60 / Q bat ), Calculate the second threshold SOC1 of the remaining power through the following formula and the relationship table between the SOC of the power battery and the peak charging power P of the power battery bat_charge_max : P bat_charge_max = P FC_eff + P FC_add + P mot_charge_max - P veh_FC_min , SOC1 = SOC0 + (P FC_eff + P FC_add - P veh_FC_min ) * (T FC_min + T FC_rat * ((P FC_eff + P FC_add ) / P FC_rat )) * 100 / 60 / Q bat , P is calculated by the following formula bat_charge_max , and then the third threshold SOC2 of the remaining power is obtained by looking up the calibrated [ambient temperature - power battery SOC - P bat_charge_max table: P bat_charge_max = P mot_charge_max + P FC_min - P veh_FC_min ; Among them, P veh_max is the maximum net output power allowed for the fuel cell of the whole vehicle, T FC_min is the shortest continuous operation time of the fuel cell power point, T FC_rat is the cold start time of the fuel cell at normal temperature rated power; Q bat is the rated capacity of the power battery, SOC min is the lower limit value of the allowable discharge of the remaining power; P bat_charge_max is the peak charging power of the power battery, P mot_charge_max is the maximum charging power of the whole vehicle for braking energy recovery, P FC_eff is the net output power point of the highest efficiency of the fuel cell, P FC_add Fuel cell power compensation value; P veh_FC_min is the minimum power consumption of the whole vehicle when the fuel cell outputs idle power; P FC_min is the idle power of the fuel cell; P FC_rat is the rated power of the fuel cell.

2. The energy distribution control method of a hydrogen fuel vehicle based on operation data according to claim 1, characterized in that: When the state of charge (SOC) of the power battery satisfies SOC ≥ SOC max , determine that the net output power P FC of the fuel cell is zero, and the SOC max is the upper limit value of the remaining charge allowed for charging.

3. The energy distribution control method of a hydrogen fuel vehicle based on operation data according to claim 1, wherein: When the state of charge (SOC) of the power battery is SOC < SOC min , determine the net output power P FC of the fuel cell as P FC = P FC_rat , where the SOC min is the lower limit of the allowable discharge of the remaining power, and P FC_rat is the rated power of the fuel cell.

4. The energy distribution control method for a hydrogen fuel vehicle based on operation data according to claim 1, characterized in that: When the state of charge (SOC) of the power battery is SOC min ≤SOC < SOC0, determine the net output power P of the fuel cell FC to be P FC = P veh_max , where the P veh_max is the maximum allowable net output power of the fuel cell for the whole vehicle.

5. The energy distribution control method of a hydrogen fuel vehicle based on operation data according to claim 1, wherein: When the state of charge (SOC) of the power battery satisfies SOC0 ≤ SOC < SOC1, determine the net output power P of the fuel cell FC to be P FC = P FC_eff + P FC_add , where the P FC_eff is the net output power point at the highest efficiency of the fuel cell, and P FC_add is the power compensation value of the fuel cell 6. The energy distribution control method for a hydrogen fuel vehicle based on operation data according to claim 1, wherein: When the state of charge (SOC) of the power battery satisfies SOC1 ≤ SOC < SOC2, determine the net output power P of the fuel cell FC to be P FC = P FC_eff , where the P FC_eff is the net output power point at the highest efficiency of the fuel cell.

7. The energy distribution control method for a hydrogen fuel vehicle based on operation data according to claim 1, wherein: When the state of charge (SOC) of the power battery satisfies SOC2 ≤ SOC < SOC max , determine the net output power P FC of the fuel cell as P FC = P veh_min ; P veh_min = P FC_min -P veh_FC_min The P veh_min is the minimum net output power of the fuel cell allowed for the whole vehicle, and P FC_min is the idling power of the fuel cell, and P veh_FC_min is the minimum power consumption of the whole vehicle when the fuel cell outputs idling power.

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