Power assist control method, device, medium and electronic equipment for hybrid vehicle

Abstract

The present disclosure relates to a power assist control method, device, medium and electronic device for a hybrid vehicle. The method comprises: when the motor of the hybrid vehicle is in a power assist state, determining the target continuous power assist correction torque and the required original power assist torque in real time; determining the minimum value between the target continuous power assist correction torque and the original power assist torque as the target power assist torque of the motor; and controlling the motor output torque according to the target power assist torque. In this way, the calculation accuracy of the target power assist torque can be improved, ensuring that the motor accurately compensates the power assist torque, meeting the power demand of the entire vehicle during the acceleration phase, and improving the user's driving experience. In addition, when determining the target power assist torque, the target continuous power assist correction torque related to the power assist sustainability capability of the hybrid vehicle is taken into consideration, which can ensure the stability and consistency of the single power assist torque when continuous power assist conditions occur, bringing better power improvement to the user, while avoiding the problem of power assist being weak in the second half of the power assist when the accelerator is continuously pressed.

Description

Technical Field

[0001] The present disclosure relates to the technical field of hybrid vehicles, and in particular to a power assist control method, device, medium, and electronic equipment for a hybrid vehicle. Background Art

[0002] Currently, energy shortages are becoming increasingly apparent, and countries around the world are calling for the development of new energy sources. China is vigorously supporting the development of the new energy vehicle industry through various policies. Hybrid vehicles can achieve the goal of reducing fuel consumption and improving drivability by adding a hybrid system to the original traditional vehicle platform. For hybrid vehicles (for example, the 48VBSG_P0 (BSG motor + traditional engine) model), when the torque provided by the engine is less than the torque required by the pedals, the power assist function needs to be activated, and the motor needs to compensate for the engine torque to ensure the power requirements of the entire vehicle. Among them, how to ensure that the motor accurately compensates for the power assist torque is the key to ensuring the power requirements of the entire vehicle and improving the user's driving experience. Summary of the Invention

[0003] In order to overcome the problems existing in the related art, the present disclosure provides a power assistance control method, device, medium and electronic equipment for a hybrid vehicle.

[0004] To achieve the above objectives, in a first aspect, the present disclosure provides a power assist control method for a hybrid vehicle, the method comprising:

[0005] When the motor of the hybrid vehicle is in a power-assisting state, determining in real time a target continuous power-assisting correction torque and a required original power-assisting torque, wherein the target continuous power-assisting correction torque is related to the power-assisting sustainability capability of the hybrid vehicle;

[0006] determining a minimum value between the target continuous assist correction torque and the original assist torque as the target assist torque of the motor;

[0007] The motor output torque is controlled according to the target assist torque.

[0008] Optionally, the real-time determination of the target continuous power-assistance correction torque includes:

[0009] acquiring in real time the actual torque, actual speed, electromechanical conversion efficiency, voltage, current, and actual temperature of the motor, the high-voltage side voltage, high-voltage side current, and conversion efficiency of a DC-DC converter connected to the motor, the voltage, actual current, actual temperature, and actual remaining charge of a power battery connected to the motor and the DC-DC converter, respectively, a first power-assistance activation duration, and a power-assistance inactivation duration, wherein the first power-assistance activation duration is the total duration of the motor in the power-assistance state from the start of the hybrid vehicle to the current moment, and the power-assistance inactivation duration is equal to the difference between the duration of the period and the first power-assistance activation duration;

[0010] determining, based on the first power-assistance activation duration, the actual torque, actual speed, electromechanical conversion efficiency, voltage, and current of the motor, the energy consumed by the motor during a power-assistance phase, wherein the power-assistance phase is the period from when the hybrid vehicle is started to the current moment, during which the motor is in the power-assistance state;

[0011] determining the energy consumed by the DC-DC converter during the power-assistance phase based on the first power-assistance activation duration, and the high-side voltage, high-side current, and conversion efficiency of the DC-DC converter;

[0012] determining the energy consumed by the power battery during the power assist phase according to the first power assist activation duration, and the voltage and actual current of the power battery;

[0013] determining a correction amount of power-assistance consumption energy based on the power-assistance inactivation time, the actual temperature and the actual remaining charge of the power battery, and the actual temperature of the motor;

[0014] determining a target energy consumed by the hybrid vehicle during the power-assistance phase according to the energy consumed by the motor during the power-assistance phase, the energy consumed by the DC-DC converter during the power-assistance phase, the energy consumed by the power battery during the power-assistance phase, and the corrected energy;

[0015] According to a preset correspondence between energy and continuous power-assistance correction torque, a continuous power-assistance correction torque corresponding to the target energy is determined as the target continuous power-assistance correction torque.

[0016] Optionally, the real-time determination of the required original assist torque includes:

[0017] Real-time acquisition of a wheel-end pedal torque demand that is limited by an automatic transmission control unit or a vehicle electronic stability system and filtered by drivability, a filtered transmission speed ratio, a speed ratio from the motor to the crankshaft end of the engine, a maximum torque of the crankshaft end, and an actual torque of the crankshaft end;

[0018] The required raw assist torque is determined based on the wheel-end pedal torque requirement after the drivability filter, the filtered gearbox speed ratio, the speed ratio from the motor to the crankshaft end of the engine, the maximum torque of the fire circuit, and the actual torque at the crankshaft end.

[0019] Optionally, the real-time determination of the required original assist torque further includes:

[0020] The original assist torque is corrected using at least one of a first correction coefficient, a second correction coefficient and a third correction coefficient, wherein the first correction coefficient is determined based on the engine speed, the actual remaining power of the power battery and the current atmospheric pressure, the second correction coefficient is inversely proportional to the second assist activation duration, and the third correction coefficient is inversely proportional to the assist rise duration. The second assist activation duration is the duration from the moment the motor last entered the assist state to the current moment, and the assist rise duration is the duration during which the assist torque is in an ascending state from the moment the motor last entered the assist state to the current moment.

[0021] Optionally, before the step of determining the minimum value of the target continuous assist correction torque and the original assist torque as the target assist torque of the motor, the method further comprises:

[0022] determining a component protection limit torque in real time, wherein the component protection limit torque is related to hardware capabilities of the motor, the DC-DC converter, and the power battery, the DC-DC converter being connected to the motor and the power battery being connected to the motor;

[0023] The step of determining the minimum value between the target continuous assist correction torque and the original assist torque as the target assist torque of the motor includes:

[0024] A minimum value among the target continuous assist correction torque, the original assist torque, and the component protection limit torque is determined as the target assist torque of the motor.

[0025] Optionally, the real-time determination of the component protection limit torque includes:

[0026] Acquire in real time the short-term maximum torque, electromechanical conversion efficiency, actual speed, and actual torque of the motor, the voltage, maximum discharge current, short-term maximum available power, actual temperature, actual current, and actual remaining capacity of the power battery, and the high-voltage side voltage and high-voltage side current of the DC-DC converter;

[0027] determining a reserved power for the power battery according to an actual speed and actual torque of the motor, a difference between the maximum discharge current and an actual current of the power battery, and an actual temperature of the power battery;

[0028] determining a first torque limit according to the electromechanical conversion efficiency and actual speed of the motor, the voltage, maximum discharge current, and short-term maximum available power of the power battery, the reserved power, and the high-voltage side voltage and high-voltage side current of the DC-DC converter;

[0029] determining a second limited torque according to an actual rotation speed of the motor, and an actual temperature and an actual remaining power of the power battery;

[0030] A minimum value among the short-term maximum torque of the motor, the first limit torque, and the second limit torque is determined as the component protection limit torque.

[0031] Optionally, before the step of controlling the motor output torque according to the target assist torque, the method further includes:

[0032] performing gradient limiting and filtering processing on the target assist torque to obtain a new target assist torque;

[0033] The step of controlling the motor output torque according to the target assist torque includes:

[0034] The motor output torque is controlled according to the new target assist torque.

[0035] In a second aspect, the present disclosure provides a power assist control device for a hybrid vehicle, comprising:

[0036] a first determining module configured to determine, in real time when the motor of the hybrid vehicle is in a power-assisting state, a target continuous power-assisting correction torque and a required original power-assisting torque, wherein the target continuous power-assisting correction torque is related to the power-assisting sustainability capability of the hybrid vehicle;

[0037] a second determining module, configured to determine a minimum value between the target continuous assist correction torque determined by the first determining module and the original assist torque as a target assist torque of the motor;

[0038] A control module is configured to control the output torque of the motor according to the target assist torque determined by the second determination module.

[0039] In a third aspect, the present disclosure provides a non-temporary computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method provided in the first aspect of the present disclosure.

[0040] In a fourth aspect, the present disclosure provides an electronic device, comprising:

[0041] a memory having a computer program stored thereon;

[0042] A processor is used to execute the computer program in the memory to implement the steps of the method provided in the first aspect of the present disclosure.

[0043] In the above technical solution, when the hybrid vehicle's motor is in a power-assist mode, a target continuous power-assistance correction torque and a required original power-assistance torque are determined in real time; the minimum of the target continuous power-assistance correction torque and the original power-assistance torque is determined as the target power-assistance torque for the motor; and the motor output torque is controlled based on the target power-assistance torque. This improves the calculation accuracy of the target power-assistance torque, ensuring that the motor can accurately compensate for the power-assistance torque, thereby meeting the vehicle's power requirements during acceleration and enhancing the user's driving experience. Furthermore, when determining the target power-assistance torque, not only the required original power-assistance torque is considered, but also the target continuous power-assistance correction torque, which is related to the hybrid vehicle's power-assistance sustainability. The target continuous power-assistance correction torque is a correction torque designed to ensure the hybrid vehicle's power-assistance performance during frequent throttle acceleration conditions and when the single-shot power-assistance function is activated. It is used to limit the original power-assistance torque, thereby ensuring the stability and consistency of the single-shot power-assistance torque during continuous power-assist conditions. This provides users with improved power performance while avoiding the issue of power-assistance weakness in the second half of a continuous throttle-on phase, improving the vehicle's overall drivability.

[0044] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following detailed description, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings:

[0046] Figure 1 The figure is a flow chart showing a power assist control method for a hybrid vehicle according to an exemplary embodiment.

[0047] Figure 2 is a schematic structural diagram of a hybrid vehicle according to an exemplary embodiment.

[0048] Figure 3 is a flowchart showing a power assistance control method for a hybrid vehicle according to another exemplary embodiment.

[0049] Figure 4 is a flowchart showing a power assistance control method for a hybrid vehicle according to another exemplary embodiment.

[0050] Figure 5 The figure is a block diagram of a power assist control device for a hybrid vehicle according to an exemplary embodiment.

[0051] Figure 6 It is a block diagram of an electronic device according to an exemplary embodiment.

[0052] Description of Reference Numerals

[0053] 1 Engine 2 DC-DC converter

[0054] 3 batteries 4 gearbox

[0055] 5 Gearbox 6 Motor

[0056] 7 Power Battery DETAILED DESCRIPTION

[0057] The following describes the specific embodiments of the present disclosure in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present disclosure and are not intended to limit the present disclosure.

[0058] Figure 1 This is a flow chart showing a power assist control method for a hybrid vehicle according to an exemplary embodiment, wherein the method can be applied to a vehicle controller. Figure 1 As shown, the method includes S101 to S103.

[0059] In S101 , when the motor of the hybrid vehicle is in the power-assisting state, a target continuous power-assisting correction torque and a required original power-assisting torque are determined in real time.

[0060] In this disclosure, the target continuous power-assistance correction torque is related to the hybrid vehicle's power-assistance sustainability capability, which refers to the hybrid vehicle's power-assistance performance under frequent accelerator pedal acceleration conditions and its power-assistance sustainability when the power-assistance function is activated once.

[0061] like Figure 2 As shown, the hybrid vehicle is primarily composed of an engine 1, a DC-DC converter 2, a battery 3, a gearbox 4, wheels 5, a motor 6, and a power battery 7. One end of the engine 1 is connected to the motor 6, and the other end is connected to one end of the gearbox 4. The DC-DC converter 2 is connected to the battery 3, the motor 6, and the power battery 7, respectively. The other end of the gearbox 4 is connected to the wheel 5. The motor 6 is connected to the power battery 7.

[0062] In addition, motor 6 can function as either a generator or a motor. When motor 6 functions as a generator, it directly charges power battery 7 and simultaneously charges battery 3 via DC-DC converter 2. When motor 6 functions as a motor, it utilizes power battery 7 to provide electrical energy for driving, while power battery 7 also supplies power to other accessories and the engine via DC-DC converter 2. Specifically, when the torque provided by engine 1 is less than the torque required by the pedals, for example, when the user accelerates by pedaling, the power assist function needs to be activated, i.e., motor 6 enters the torque assist state. Thereafter, motor 6 is used to provide torque compensation (i.e., assist) to engine 1 to ensure the power requirements of the vehicle. When motor 6 is in the torque assist state, a portion of the electrical energy output by power battery 7 is consumed by battery 3 via DC-DC converter 2, while the remaining portion is consumed by motor 6 for assisting. Battery 3 can be connected to low-voltage loads to provide power to them. For example, low-voltage loads may include non-driving electrical devices such as instruments, lights, audio-visual equipment, and air conditioners.

[0063] For example, the motor 6 may be a BSG motor, an ISG motor, etc., the voltage of the battery 3 is 12V, and the voltage of the power battery is 48V.

[0064] In S102 , the minimum value between the target continuous assist correction torque and the original assist torque is determined as the target assist torque of the motor;

[0065] In S103 , the motor output torque is controlled according to the target assist torque.

[0066] In the above technical solution, when the hybrid vehicle's motor is in a power-assist mode, a target continuous power-assistance correction torque and a required original power-assistance torque are determined in real time; the minimum of the target continuous power-assistance correction torque and the original power-assistance torque is determined as the target power-assistance torque for the motor; and the motor output torque is controlled based on the target power-assistance torque. This improves the calculation accuracy of the target power-assistance torque, ensuring that the motor can accurately compensate for the power-assistance torque, thereby meeting the vehicle's power requirements during acceleration and enhancing the user's driving experience. Furthermore, when determining the target power-assistance torque, not only the required original power-assistance torque is considered, but also the target continuous power-assistance correction torque, which is related to the hybrid vehicle's power-assistance sustainability. The target continuous power-assistance correction torque is a correction torque designed to ensure the hybrid vehicle's power-assistance performance during frequent throttle acceleration conditions and when the single-shot power-assistance function is activated. It is used to limit the original power-assistance torque, thereby ensuring the stability and consistency of the single-shot power-assistance torque during continuous power-assist conditions. This provides users with improved power performance while avoiding the issue of power-assistance weakness in the second half of a continuous throttle-on phase, improving the vehicle's overall drivability.

[0067] The following is a detailed description of the specific implementation method for determining the target continuous power-assisted correction torque in real time in the above S101. Specifically, it can be achieved through the following steps (1) to (7):

[0068] (1) Real-time acquisition of the actual torque, actual speed, electromechanical conversion efficiency, voltage, current and actual temperature of the motor, the high-voltage side voltage, high-voltage side current and conversion efficiency of the DC-DC converter connected to the motor, the voltage, actual current, actual temperature and actual remaining capacity (State Of Charge, SOC) of the power battery connected to the motor and the DC-DC converter respectively, the first power assist activation time and the power assist inactivation time.

[0069] Among them, the first power-assistance activation time is the total time that the motor is in the power-assistance state from the start of the hybrid vehicle to the current moment, and the power-assistance inactivation time is equal to the difference between the time period and the first power-assistance activation time.

[0070] (2) Determine the energy consumed by the motor during the assist phase based on the first assist activation duration, the actual torque, actual speed, electromechanical conversion efficiency, voltage, and current of the motor.

[0071] The power-assist phase is the period from when the hybrid vehicle is started to the current moment, when the motor is in the power-assist state.

[0072] For example, the energy E(B) consumed by the motor during the assist phase can be determined by the following equation (1) based on the first assist activation duration, the actual torque, the actual speed, the electromechanical conversion efficiency, the voltage, and the current of the motor:

[0073]

[0074] Among them, T(B_Act) is the actual torque of the motor; n(B_rpm) is the actual speed of the motor; η(B) is the electromechanical conversion efficiency of the motor; U(B) is the voltage of the motor; I(B) is the current of the motor; t1 is the activation time of the first power assist.

[0075] (3) Determine the energy consumed by the DC-DC converter during the assist phase based on the first assist activation duration, the high-voltage side voltage, the high-voltage side current, and the conversion efficiency of the DC-DC converter.

[0076] For example, the energy consumed by the DC-DC converter in the power-assistance phase, E(DCDC), can be determined by the following equation (2) based on the first power-assistance activation duration, the high-side voltage, the high-side current, and the conversion efficiency of the DC-DC converter:

[0077] E(DCDC)=∫U(DC_Hv)*I(DC_Hv)*η(DCDC)dt1 (2)

[0078] Wherein, U(DC_Hv) is the high-voltage side voltage of the DC-DC converter; I(DC_Hv) is the high-voltage side current of the DC-DC converter; and η(DCDC) is the conversion efficiency of the DC-DC converter.

[0079] (4) Determine the energy consumed by the power battery during the power assist phase based on the first power assist activation duration, as well as the voltage and actual current of the power battery.

[0080] For example, the energy E(BMS) consumed by the power battery during the power assist phase can be determined according to the first power assist activation duration, the voltage and actual current of the power battery using the following equation (3):

[0081] E(BMS)=∫U(BMS)*I(BMS)dt1 (3)

[0082] Among them, U(BMS) is the voltage of the power battery; I(BMS) is the actual current of the power battery.

[0083] (5) Determine the correction energy of the power assist energy consumption based on the power assist inactivation time, the actual temperature and actual SOC of the power battery, and the actual temperature of the motor.

[0084] Because hybrid vehicles may enter the power-assisted state again within a short period of time after the power-assisted function ends, the power-assisted energy consumption cannot be reset to zero immediately after the power-assisted function ends, but needs to decrease slowly over time. To this end, a correction value for the power-assisted energy consumption after the power-assisted function ends is set.

[0085] (6) Determine the target energy consumed by the hybrid vehicle during the power-assistance phase based on the energy consumed by the motor during the power-assistance phase, the energy consumed by the DC-DC converter during the power-assistance phase, the energy consumed by the power battery during the power-assistance phase, and the correction energy of the power-assistance consumed energy.

[0086] For example, the target energy E(sum) consumed by the hybrid vehicle during the power-assistance phase can be determined by the following equation (4) based on the energy consumed by the motor during the power-assistance phase, the energy consumed by the DC-DC converter during the power-assistance phase, the energy consumed by the power battery during the power-assistance phase, and the correction energy of the power-assistance consumed energy:

[0087] E(sum)=Max[E(B)+E(DCDC)-E(dec),E(BMS)-E(dec)] (4)

[0088] Wherein, E(dec) is the correction energy of the power assist consumption energy.

[0089] (7) According to the preset correspondence between the energy and the continuous power-assistance correction torque, the continuous power-assistance correction torque corresponding to the target energy is determined as the target continuous power-assistance correction torque.

[0090] Among them, in the above preset corresponding relationship between energy and continuous power-assistance correction torque, energy and continuous power-assistance correction torque are in inverse proportional relationship.

[0091] The following describes in detail the specific implementation method for determining the correction energy of the power assist consumption based on the power assist inactivation time, the actual temperature and actual SOC of the power battery, and the actual temperature of the motor in step (5). Specifically, it can be achieved by:

[0092] First, based on the pre-constructed correspondence between the temperature of the power battery, the SOC of the power battery, the temperature of the motor and the correction power of the power-assisted energy consumption, the target correction power of the power-assisted energy consumption corresponding to the actual temperature of the power battery, the actual SOC of the power battery and the actual temperature of the motor is determined; then, based on the target correction power and the length of time the power assist is not activated, the correction energy of the power-assisted energy consumption is determined.

[0093] For example, the corrected energy E(dec) of the assist consumption energy can be determined according to the target corrected power and the assist inactive time by the following equation (5):

[0094] E(dec)=∫P(dec)dt2 (5)

[0095] Where P(dec) is the target corrected power; t2 is the duration for which the power assist is not activated.

[0096] It should be noted that during the aforementioned power-assist phase, the motor's actual torque, speed, voltage, current, and temperature; the DC-DC converter's high-side voltage and current; and the battery's voltage, current, temperature, and SOC all change dynamically over time. The subsequent determination of the original power-assist torque and component protection limit torque uses the current parameter values ​​of each component.

[0097] The following describes in detail the specific implementation of the real-time determination of the required original assist torque in S101. Specifically, it can be achieved by:

[0098] First, the wheel-end pedal torque demand, which is limited by the automatic transmission control unit or the vehicle electronic stability system and filtered by drivability, the filtered transmission speed ratio, the speed ratio from the motor to the crankshaft end of the engine, the maximum torque of the fire circuit at the crankshaft end, and the actual torque at the crankshaft end are obtained in real time; then, the required original assist torque is determined based on the wheel-end pedal torque demand, which is filtered by the drivability, the filtered transmission speed ratio, the speed ratio from the motor to the crankshaft end of the engine, the maximum torque of the fire circuit, and the actual torque at the crankshaft end.

[0099] For example, the required raw assist torque T (BSG_Assist_Raw) can be determined by the following equation (6) based on the wheel-end pedal torque requirement after drivability filtering, the filtered gearbox speed ratio, the speed ratio from the motor to the crankshaft end of the engine, the maximum torque of the fire circuit, and the actual torque at the crankshaft end:

[0100] T(BSG_Assist_Raw)=[T(Tgt_Filter)-T(Eng_max)]*Rat(BSG_Eng) (6)

[0101] Among them, T(Tgt_Filter) is the crankshaft end pedal torque demand limited by the automatic transmission control unit or the vehicle electronic stability system and after drivability filtering, and T(Tgt_Filter) = T(Whl_Filter) / Rat(Trsm_Filter), T(Whl_Filter) is the wheel end pedal torque demand after drivability filtering, Rat(Trsm_Filter) is the transmission speed ratio after filtering; T(Eng_max) is the maximum torque that the current engine can provide, and T(Eng_max) = Min[T(Eng_set_max), T(Eng_Act)], T(Eng_set_max) is the above-mentioned maximum torque of the fire circuit, T(Eng_Act) is the above-mentioned actual torque of the crankshaft end; Rat(BSG_Eng) is the speed ratio from the motor to the crankshaft end of the engine.

[0102] In the above embodiment, the wheel-end pedal torque demand after driving filtering is used to determine the required original assist torque, taking into account the slow rise characteristic of the torque, thereby improving the accuracy of the original assist torque calculation, making the calculated required original assist torque closer to the torque actually required by the vehicle, and avoiding over-compensation or under-compensation of the engine by the motor.

[0103] In addition, to improve the accuracy of the original assist torque and further enhance the precision of the target assist torque, the required original assist torque calculated based on the filtered wheel-end pedal torque demand, the filtered transmission speed ratio, the motor-to-engine crankshaft speed ratio, the maximum torque of the power circuit, and the actual torque at the crankshaft can be corrected. Specifically, the step of determining the required original assist torque in real time in S101 further includes the following steps:

[0104] The original assist torque is corrected using at least one of the first correction coefficient, the second correction coefficient, and the third correction coefficient.

[0105] Among them, the first correction coefficient is determined according to the engine speed, the actual SOC of the power battery and the current atmospheric pressure. The second correction coefficient is inversely proportional to the second power-assistance activation time. The third correction coefficient is inversely proportional to the power-assistance increase time. The second power-assistance activation time is the time from the last time the motor entered the power-assistance state to the current moment. The power-assistance increase time is the time when the power-assistance torque is in the increasing state during the period from the last time the motor entered the power-assistance state to the current moment.

[0106] In one implementation, the original assist torque may be corrected using any one of the first correction coefficient, the second correction coefficient, and the third correction coefficient.

[0107] For example, the first correction coefficient may be used to correct the original assist torque to avoid the influence of atmospheric pressure, SOC of the power battery, and engine speed on the accuracy of the original assist torque, thereby improving the calculation accuracy of the target assist torque.

[0108] As another example, the original power assist torque can be corrected using a second correction coefficient, where the second correction coefficient is inversely proportional to the second power assist activation duration. During continuous discharge of the power battery, the discharge capacity decreases as the discharge duration increases. The electric motor, using the power battery, provides power to the engine to compensate for the torque. Therefore, as the second power assist activation duration increases, the motor's compensation torque decreases. In other words, the original power assist torque decreases as the second activation duration increases, thereby ensuring power assist stability and consistent vehicle driving experience.

[0109] As another example, the original assist torque can be corrected using a third correction coefficient, wherein the third correction coefficient is inversely proportional to the assist rise time. In this way, the rising gradient of the original assist torque can be guaranteed, so that the torque provided by the motor matches the required assist torque.

[0110] Specifically, any one of the first correction coefficient, the second correction coefficient, and the third correction coefficient may be multiplied by the original assist torque to correct the original assist torque.

[0111] For example, the original assist torque can be corrected using the first correction coefficient by the following equation (7):

[0112] T(BSG_Assist_Raw1)=T(BSG_Assist_Raw)*K1 (7)

[0113] Wherein, T(BSG_Assist_Raw1) is the original assist torque obtained after correction; K1 is the first correction coefficient.

[0114] In another embodiment, the original assist torque may be corrected using any two of the first correction coefficient, the second correction coefficient, and the third correction coefficient.

[0115] Specifically, any two of the first correction coefficient, the second correction coefficient, and the third correction coefficient may be multiplied by the original assist torque to correct the original assist torque.

[0116] For example, the second correction coefficient and the third correction coefficient may be used to correct the original assist torque using the following equation (8):

[0117] T(BSG_Assist_Raw1)=T(BSG_Assist_Raw)*K2*K3 (8)

[0118] Among them, K2 is the second correction coefficient; K3 is the third correction coefficient.

[0119] In yet another embodiment, the original assist torque may be corrected using the first correction coefficient, the second correction coefficient, and the third correction coefficient.

[0120] Specifically, the first correction coefficient, the second correction coefficient, and the third correction coefficient can be multiplied by the original power-assist torque to correct the original power-assist torque. That is, the original power-assist torque can be corrected by the following equation (9):

[0121] T(BSG_Assist_Raw1)=T(BSG_Assist_Raw)*K1*K2*K3 (9)

[0122] In addition, in order to ensure that components such as power batteries, motors, and DC-DC converters can operate within their normal capacity range, the capacity limitations of components such as power batteries, motors, and DC-DC converters must also be considered when determining the target assist torque to avoid problems such as over-discharge of the power battery. Specifically, Figure 3 As shown, before the above S102, the above method also includes S104.

[0123] In S104 , the component protection limit torque is determined in real time.

[0124] In this disclosure, the component protection limit torque is related to the hardware capabilities of the motor, DC-DC converter, and power battery. Thus, S102 can determine the minimum of the target continuous power assist correction torque, the original power assist torque, and the component protection limit torque as the target power assist torque for the motor.

[0125] The following describes in detail the specific implementation of the above-mentioned S104 for determining the component protection limit torque in real time. Specifically, it can be achieved by following the steps ① to ⑤:

[0126] ① Obtain in real time the short-term maximum torque, electromechanical conversion efficiency, actual speed and actual torque of the motor, the voltage, maximum discharge current, short-term maximum available power, actual temperature, actual current and actual SOC of the power battery, as well as the high-voltage side voltage and high-voltage side current of the DC-DC converter.

[0127] Among them, the short-time maximum torque of the motor can be, for example, the maximum torque of the motor within the current 2 seconds, which can be calculated by the motor; the short-time maximum available power of the power battery can be, for example, the maximum available power of the power battery within the current 2 seconds, which can be calculated by the battery management system.

[0128] ② Determine the reserved power for the power battery based on the actual speed and actual torque of the motor, the difference between the maximum discharge current and the actual current of the power battery, and the actual temperature of the power battery.

[0129] When the motor is in torque-assist mode, part of the power battery's output energy is consumed by the DC-DC converter and then used by the motor for assist. Therefore, to prevent over-discharge of the power battery during the assist phase, it's necessary to reserve the battery's available power, i.e., determine the reserved power.

[0130] ③ Determine the first limiting torque based on the electromechanical conversion efficiency and actual speed of the motor, the voltage, maximum discharge current and short-time maximum available power of the power battery, the reserved power, and the high-voltage side voltage and high-voltage side current of the DC-DC converter.

[0131] For example, the first limit torque T(BMS_DC_s) can be determined by the following equation (10) based on the electromechanical conversion efficiency and actual speed of the motor, the voltage, maximum discharge current and short-time maximum available power of the power battery, the reserved power, and the high-voltage side voltage and high-voltage side current of the DC-DC converter:

[0132]

[0133] Among them, P(BMS_s) is the short-term maximum available power of the power battery; P(BMS_Lim) is the maximum discharge power of the power battery, and P(BMS_Lim) = U(BMS)*I(BMS_Lim), I(BMS_Lim) is the maximum discharge current of the power battery; P(Offset) is the reserved power; P(DC_Act) is the actual power consumption on the high-voltage side of the DC-DC converter, and P(DC_Act) = U(DC_Hv)*I(DC_Hv).

[0134] ④ Determine the second torque limit based on the actual speed of the motor, the actual temperature of the power battery, and the actual SOC.

[0135] ⑤ The minimum value among the short-time maximum torque of the motor, the first limit torque and the second limit torque is determined as the component protection limit torque.

[0136] Since the discharge capacity of power batteries at different temperatures and different SOCs varies greatly, especially under conditions where the motor speed and torque change drastically, even with a torque limit based on the capabilities of the power battery and DC-DC converter, for component safety considerations, we still need to further limit the target assist torque based on the actual motor speed, the actual SOC of the power battery, and the actual temperature, that is, determine the target assist torque based on the second torque limit.

[0137] The following describes in detail the specific implementation method for determining the second torque limit in step ④ based on the actual speed of the motor, the actual temperature and the actual SOC of the power battery. Specifically, it can be achieved by:

[0138] First, based on the preset correspondence between the motor speed and the limit torque, the target limit torque corresponding to the actual motor speed is determined; then, based on the preset correspondence between the power battery SOC, the power battery temperature and the correction coefficient, the target correction coefficient corresponding to the actual power battery SOC and the actual power battery temperature is determined; finally, the product of the target limit torque and the target correction coefficient is determined as the second limit torque.

[0139] In addition, in order to ensure the stability and smoothness of the vehicle, Figure 4 As shown, before the above S103, the above method further includes S105:

[0140] In S105 , the target assist torque is subjected to gradient limiting and filtering to obtain a new target assist torque.

[0141] In this way, the above S103 can control the motor output torque according to the new target assist torque.

[0142] Based on the same inventive concept, the present disclosure also provides a power assist control device for a hybrid vehicle. Figure 5 As shown, the device 500 includes: a first determination module 501, which is used to determine the target continuous power-assistance correction torque and the required original power-assistance torque in real time when the motor of the hybrid vehicle is in a power-assistance state, wherein the target continuous power-assistance correction torque is related to the power-assistance sustainability capability of the hybrid vehicle; a second determination module 502, which is used to determine the minimum value between the target continuous power-assistance correction torque and the original power-assistance torque determined by the first determination module 501 as the target power-assistance torque of the motor; and a control module 503, which is used to control the output torque of the motor according to the target power-assistance torque determined by the second determination module 502.

[0143] In the above technical solution, when the hybrid vehicle's motor is in a power-assist mode, a target continuous power-assistance correction torque and a required original power-assistance torque are determined in real time; the minimum of the target continuous power-assistance correction torque and the original power-assistance torque is determined as the target power-assistance torque for the motor; and the motor output torque is controlled based on the target power-assistance torque. This improves the calculation accuracy of the target power-assistance torque, ensuring that the motor can accurately compensate for the power-assistance torque, thereby meeting the vehicle's power requirements during acceleration and enhancing the user's driving experience. Furthermore, when determining the target power-assistance torque, not only the required original power-assistance torque is considered, but also the target continuous power-assistance correction torque, which is related to the hybrid vehicle's power-assistance sustainability. The target continuous power-assistance correction torque is a correction torque designed to ensure the hybrid vehicle's power-assistance performance during frequent throttle acceleration conditions and when the single-shot power-assistance function is activated. It is used to limit the original power-assistance torque, thereby ensuring the stability and consistency of the single-shot power-assistance torque during continuous power-assist conditions. This provides users with improved power performance while avoiding the issue of power-assistance weakness in the second half of a continuous throttle-on phase, improving the vehicle's overall drivability.

[0144] Optionally, the first determining module 501 includes:

[0145] a first acquisition submodule, for acquiring in real time the actual torque, actual speed, electromechanical conversion efficiency, voltage, current, and actual temperature of the motor, the high-voltage side voltage, high-voltage side current, and conversion efficiency of a DC-DC converter connected to the motor, the voltage, actual current, actual temperature, and actual remaining charge of a power battery connected to the motor and the DC-DC converter, respectively, a first power-assistance activation duration, and a power-assistance inactivation duration, wherein the first power-assistance activation duration is the total duration of the motor in the power-assistance state from the start of the hybrid vehicle to the current moment, and the power-assistance inactivation duration is equal to the difference between the duration of the period and the first power-assistance activation duration;

[0146] a motor energy consumption determination submodule, configured to determine energy consumed by the motor during a power-assistance phase based on the first power-assistance activation duration, as well as the actual torque, actual speed, electromechanical conversion efficiency, voltage, and current of the motor, wherein the power-assistance phase is the period from when the hybrid vehicle is started to the current moment, during which the motor is in the power-assistance state;

[0147] a converter energy consumption determination submodule, configured to determine the energy consumed by the DC-DC converter during the power-assistance phase based on the first power-assistance activation duration, and the high-side voltage, high-side current, and conversion efficiency of the DC-DC converter;

[0148] a battery energy consumption determination submodule, configured to determine the energy consumed by the power battery during the power assist phase based on the first power assist activation duration, and the voltage and actual current of the power battery;

[0149] a correction energy determination submodule, configured to determine a correction energy for the power-assistance consumption based on the power-assistance inactivation time, the actual temperature and the actual remaining power of the power battery, and the actual temperature of the motor;

[0150] a target energy determination submodule, configured to determine a target energy consumed by the hybrid vehicle during the power-assistance phase based on the energy consumed by the motor during the power-assistance phase, the energy consumed by the DC-DC converter during the power-assistance phase, the energy consumed by the power battery during the power-assistance phase, and the corrected energy;

[0151] The correction torque determination submodule is configured to determine the continuous power-assistance correction torque corresponding to the target energy according to a preset correspondence between the energy and the continuous power-assistance correction torque, as the target continuous power-assistance correction torque.

[0152] Optionally, the first determining module 501 includes:

[0153] a second acquisition submodule, for acquiring in real time a wheel-end pedal torque demand that is limited by an automatic transmission control unit or a vehicle electronic stability system and filtered by drivability, a filtered transmission speed ratio, a speed ratio from the motor to the crankshaft end of the engine, a maximum torque of the crankshaft end, and an actual torque of the crankshaft end;

[0154] The original assist torque determination submodule is used to determine the required original assist torque based on the wheel-end pedal torque requirement after the drivability filter, the filtered gearbox speed ratio, the speed ratio from the motor to the crankshaft end of the engine, the maximum torque of the fire circuit and the actual torque at the crankshaft end.

[0155] Optionally, the first determining module 501 further includes:

[0156] A correction submodule is used to correct the original power-assisting torque using at least one of a first correction coefficient, a second correction coefficient and a third correction coefficient, wherein the first correction coefficient is determined based on the engine speed, the actual remaining power of the power battery and the current atmospheric pressure, the second correction coefficient is inversely proportional to the second power-assisting activation duration, and the third correction coefficient is inversely proportional to the power-assisting increase duration. The second power-assisting activation duration is the duration from the moment the motor last entered the power-assisting state to the current moment, and the power-assisting increase duration is the duration during which the power-assisting torque is in an increasing state from the moment the motor last entered the power-assisting state to the current moment.

[0157] Optionally, the apparatus 500 further includes:

[0158] a third determining module, configured to determine, in real time, a component protection limit torque before the second determining module 502 determines the minimum of the target continuous power-assistance correction torque and the original power-assistance torque as the target power-assistance torque of the motor, wherein the component protection limit torque is related to hardware capabilities of the motor, the DC-DC converter, and the power battery, the DC-DC converter being connected to the motor and the power battery, respectively, and the power battery being connected to the motor;

[0159] The second determining module 502 is configured to determine a minimum value among the target continuous assist correction torque, the original assist torque, and the component protection limit torque as the target assist torque of the motor.

[0160] Optionally, the third determining module includes:

[0161] A third acquisition submodule is used to obtain in real time the short-term maximum torque, electromechanical conversion efficiency, actual speed and actual torque of the motor, the voltage, maximum discharge current, short-term maximum available power, actual temperature, actual current and actual remaining power of the power battery, and the high-voltage side voltage and high-voltage side current of the DC-DC converter;

[0162] a reserved power determination submodule, configured to determine the reserved power for the power battery based on the actual speed and actual torque of the motor, the difference between the maximum discharge current and the actual current of the power battery, and the actual temperature of the power battery;

[0163] a first torque limit determination submodule, configured to determine a first torque limit based on the electromechanical conversion efficiency and actual speed of the motor, the voltage, maximum discharge current, and short-term maximum available power of the power battery, the reserved power, and the high-voltage side voltage and high-voltage side current of the DC-DC converter;

[0164] a second torque limit determination submodule, configured to determine a second torque limit according to an actual rotational speed of the motor, and an actual temperature and an actual remaining capacity of the power battery;

[0165] The component protection limit torque determination submodule is configured to determine the minimum value among the short-term maximum torque of the motor, the first limit torque, and the second limit torque as the component protection limit torque.

[0166] Optionally, the apparatus 500 further includes:

[0167] a processing module configured to perform gradient limiting and filtering processing on the target assist torque to obtain a new target assist torque before the control module 503 controls the motor output torque according to the target assist torque;

[0168] The control module 503 is configured to control the motor output torque according to the new target assist torque.

[0169] Regarding the apparatus in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0170] Figure 6 FIG. 7 is a block diagram of an electronic device 700 according to an exemplary embodiment. Figure 6 As shown, the electronic device 700 may include: a processor 701 , a memory 702 , and may further include one or more of a multimedia component 703 , an input / output (I / O) interface 704 , and a communication component 705 .

[0171] The processor 701 is used to control the overall operation of the electronic device 700 to complete all or part of the steps in the aforementioned power assist control method for a hybrid vehicle. The memory 702 is used to store various types of data to support the operation of the electronic device 700. This data may include, for example, instructions for any application or method operating on the electronic device 700, as well as application-related data, such as contact information, sent and received messages, images, audio, video, etc. The memory 702 can be implemented by any type of volatile or non-volatile storage device, or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The multimedia component 703 may include a screen and an audio component. The screen may be, for example, a touch screen, and the audio component is used to output and / or input audio signals. For example, the audio component may include a microphone for receiving external audio signals. The received audio signal may be further stored in the memory 702 or sent via the communication component 705. The audio component also includes at least one speaker for outputting audio signals. The I / O interface 704 provides an interface between the processor 701 and other interface modules. The above-mentioned other interface modules may be a keyboard, a mouse, buttons, etc. These buttons may be virtual buttons or physical buttons. The communication component 705 is used for wired or wireless communication between the electronic device 700 and other devices. Wireless communication, such as Wi-Fi, Bluetooth, Near Field Communication (NFC), 2G, 3G, 4G, NB-IOT, eMTC, or other 5G, etc., or a combination of one or more thereof, is not limited here. Therefore, the corresponding communication component 705 may include: a Wi-Fi module, a Bluetooth module, an NFC module, etc.

[0172] In an exemplary embodiment, the electronic device 700 may be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components to execute the aforementioned power assist control method for a hybrid vehicle.

[0173] In another exemplary embodiment, a computer-readable storage medium including program instructions is also provided. When executed by a processor, the program instructions implement the steps of the aforementioned power assist control method for a hybrid vehicle. For example, the computer-readable storage medium may be the aforementioned memory 702 including the program instructions. The program instructions may be executed by the processor 701 of the electronic device 700 to implement the aforementioned power assist control method for a hybrid vehicle.

[0174] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings. However, the present disclosure is not limited to the specific details of the above embodiments. Within the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the scope of protection of the present disclosure.

[0175] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0176] In addition, the various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A power assist control method for a hybrid vehicle, characterized in that: Methods include: When the motor of the hybrid vehicle is in a power-assisting state, determining in real time a target continuous power-assisting correction torque and a required original power-assisting torque, wherein the target continuous power-assisting correction torque is related to the power-assisting sustainability capability of the hybrid vehicle; determining a component protection limit torque in real time, wherein the component protection limit torque is related to hardware capabilities of the motor, the DC-DC converter, and the power battery, the DC-DC converter being connected to the motor and the power battery being connected to the motor; determining a minimum value between the target continuous assist correction torque and the original assist torque as the target assist torque of the motor; controlling the motor output torque according to the target assist torque; The step of determining the minimum value between the target continuous assist correction torque and the original assist torque as the target assist torque of the motor includes: A minimum value among the target continuous assist correction torque, the original assist torque, and the component protection limit torque is determined as the target assist torque of the motor.

2. The method according to claim 1, characterized in that The real-time determination of the target continuous power-assistance correction torque includes: acquiring in real time the actual torque, actual speed, electromechanical conversion efficiency, voltage, current, and actual temperature of the motor, the high-voltage side voltage, high-voltage side current, and conversion efficiency of a DC-DC converter connected to the motor, the voltage, actual current, actual temperature, and actual remaining charge of a power battery connected to the motor and the DC-DC converter, respectively, a first power-assistance activation duration, and a power-assistance inactivation duration, wherein the first power-assistance activation duration is the total duration of the motor in the power-assistance state from the start of the hybrid vehicle to the current moment, and the power-assistance inactivation duration is equal to the difference between the duration of the period and the first power-assistance activation duration; determining, based on the first power-assistance activation duration, the actual torque, actual speed, electromechanical conversion efficiency, voltage, and current of the motor, the energy consumed by the motor during a power-assistance phase, wherein the power-assistance phase is the period from when the hybrid vehicle is started to the current moment, during which the motor is in the power-assistance state; determining the energy consumed by the DC-DC converter during the power-assistance phase based on the first power-assistance activation duration, and the high-side voltage, high-side current, and conversion efficiency of the DC-DC converter; determining the energy consumed by the power battery during the power assist phase according to the first power assist activation duration, and the voltage and actual current of the power battery; determining a correction amount of power-assistance consumption energy based on the power-assistance inactivation time, the actual temperature and the actual remaining charge of the power battery, and the actual temperature of the motor; determining a target energy consumed by the hybrid vehicle during the power-assistance phase according to the energy consumed by the motor during the power-assistance phase, the energy consumed by the DC-DC converter during the power-assistance phase, the energy consumed by the power battery during the power-assistance phase, and the corrected energy; According to a preset correspondence between energy and continuous power-assistance correction torque, a continuous power-assistance correction torque corresponding to the target energy is determined as the target continuous power-assistance correction torque.

3. The method according to claim 1, characterized in that The real-time determination of the required raw assist torque includes: Real-time acquisition of a wheel-end pedal torque demand that is limited by an automatic transmission control unit or a vehicle electronic stability system and filtered by drivability, a filtered transmission speed ratio, a speed ratio from the motor to the crankshaft end of the engine, a maximum torque of the crankshaft end, and an actual torque at the crankshaft end; The required raw assist torque is determined based on the wheel-end pedal torque requirement after the drivability filter, the filtered gearbox speed ratio, the speed ratio from the motor to the crankshaft end of the engine, the maximum torque of the fire circuit, and the actual torque at the crankshaft end.

4. The method according to claim 3, characterized in that The real-time determination of the required original assist torque further includes: The original assist torque is corrected using at least one of a first correction coefficient, a second correction coefficient and a third correction coefficient, wherein the first correction coefficient is determined based on the engine speed, the actual remaining power of the power battery and the current atmospheric pressure, the second correction coefficient is inversely proportional to the second assist activation duration, and the third correction coefficient is inversely proportional to the assist rise duration. The second assist activation duration is the duration from the moment the motor last entered the assist state to the current moment, and the assist rise duration is the duration during which the assist torque is in an ascending state from the moment the motor last entered the assist state to the current moment.

5. The method according to claim 1, wherein The real-time determination of the component protection limit torque includes: Acquire in real time the short-term maximum torque, electromechanical conversion efficiency, actual speed, and actual torque of the motor, the voltage, maximum discharge current, short-term maximum available power, actual temperature, actual current, and actual remaining capacity of the power battery, and the high-voltage side voltage and high-voltage side current of the DC-DC converter; determining a reserved power for the power battery according to an actual speed and actual torque of the motor, a difference between the maximum discharge current and an actual current of the power battery, and an actual temperature of the power battery; determining a first torque limit according to the electromechanical conversion efficiency and actual speed of the motor, the voltage, maximum discharge current, and short-term maximum available power of the power battery, the reserved power, and the high-voltage side voltage and high-voltage side current of the DC-DC converter; determining a second torque limit according to an actual rotation speed of the motor, and an actual temperature and an actual remaining power of the power battery; A minimum value among the short-term maximum torque of the motor, the first limit torque, and the second limit torque is determined as the component protection limit torque.

6. The method according to any one of claims 1 to 5, characterized in that Before the step of controlling the motor output torque according to the target assist torque, the method further includes: performing gradient limiting and filtering processing on the target assist torque to obtain a new target assist torque; The controlling the motor output torque according to the target assist torque includes: The motor output torque is controlled according to the new target assist torque.

7. A power assist control device for a hybrid vehicle, characterized in that: include: a first determining module configured to determine, in real time when the motor of the hybrid vehicle is in a power-assisting state, a target continuous power-assisting correction torque and a required original power-assisting torque, wherein the target continuous power-assisting correction torque is related to the power-assisting sustainability capability of the hybrid vehicle; a third determination module, configured to determine in real time a component protection limit torque, wherein the component protection limit torque is related to hardware capabilities of the motor, the DC-DC converter, and the power battery, the DC-DC converter being connected to the motor and the power battery being connected to the motor; a second determining module, configured to determine a minimum value between the target continuous assist correction torque determined by the first determining module and the original assist torque as a target assist torque of the motor; a control module, configured to control the output torque of the motor according to the target assist torque determined by the second determination module; The second determination module is configured to determine a minimum value among the target continuous assist correction torque, the original assist torque, and the component protection limit torque as the target assist torque of the motor.

8. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

9. An electronic device, characterized in that: include: a memory having a computer program stored thereon; A processor, configured to execute the computer program in the memory to implement the steps of the method according to any one of claims 1 to 6.

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