Engine idle speed control method for hybrid vehicle, storage medium and vehicle

Abstract

This application provides an engine idling speed control method, storage medium, and vehicle for a hybrid vehicle, belonging to the field of vehicle control technology. The embodiments of this application identify the triggering mode of the engine idling condition, enabling the matching of a corresponding target proportional-integral (PI) control strategy based on the triggering mode. Based on the target PI control strategy, the PI adjustment torque of the electric motor is determined, effectively meeting the engine idling speed control requirements under various idling conditions. Simultaneously, based on the PI adjustment and combined with the current engine speed difference, torque compensation for the electric motor can be achieved. Then, based on the PI adjustment torque and the compensation torque, the first motor execution torque is determined, and the motor is controlled to output torque according to the first motor execution torque. Utilizing the rapid response characteristics of the electric motor, rapid and stable control of the engine idling speed is achieved.

Description

Technical Field

[0001] This application relates to the field of vehicle control technology, and in particular to an engine idling speed control method, storage medium, and vehicle for a hybrid vehicle. Background Technology

[0002] Currently, when a vehicle's engine enters idling mode, the engine speed is usually adjusted using PID control (proportional-integral-derivative control).

[0003] However, traditional PID control only has one calibration map in real vehicles, while the idling conditions in real vehicle control are more complex, and a single set of control parameters is difficult to meet all the conditions of engine idling control. At the same time, as the vehicle runs for a long time, the vehicle performance parameters will change irreversibly, and different vehicle states are inconsistent. It is difficult to meet the precise control of the target idling speed of real vehicles by relying solely on PID control. Summary of the Invention

[0004] This application provides a method, device, storage medium, and vehicle for controlling engine idling speed in hybrid vehicles, in order to solve the problem that current methods for controlling engine idling speed in hybrid vehicles are limited and make it difficult to achieve rapid and stable control of engine idling speed under different idling conditions.

[0005] To solve the above problems, this application adopts the following technical solution:

[0006] In a first aspect, embodiments of this application provide an engine idling speed control method for a hybrid vehicle, the method comprising:

[0007] Based on the triggering method of the engine idling condition, the target proportional-integral control strategy corresponding to the triggering method is determined; wherein, different triggering methods correspond to different proportional-integral control strategies.

[0008] Based on the target proportional-integral control strategy, the proportional-integral adjustment torque of the motor is determined;

[0009] The compensation torque of the motor is determined based on the current speed difference between the current speed of the engine and the target idle speed.

[0010] Based on the proportional-integral adjustment torque and the compensation torque, the first motor execution torque of the motor is determined, and the motor is controlled to output torque according to the first motor execution torque to adjust the current speed of the engine.

[0011] In one embodiment of this application, the step of determining the target proportional-integral control strategy corresponding to the triggering mode based on the engine's idling condition includes:

[0012] When the triggering method is detected as the driver releasing the accelerator pedal, the target proportional-integral control strategy is determined to be a first proportional-integral control strategy; the first proportional-integral control strategy is a strategy that limits the rate of change of the current speed.

[0013] If the triggering method is not the driver releasing the accelerator pedal, the target proportional-integral control strategy is determined to be the second proportional-integral control strategy; the second proportional-integral control strategy is a strategy that does not limit the rate of change of the current speed.

[0014] In one embodiment of this application, the step of determining the proportional-integral (PI) regulating torque of the motor based on the target PI control strategy includes:

[0015] When the target proportional-integral control strategy is the second proportional-integral control strategy, the current speed of the engine and the current speed difference between the current speed and the target idle speed are determined;

[0016] The proportional-integral adjustment torque is determined based on the current rotational speed and the current rotational speed difference.

[0017] In one embodiment of this application, the step of determining the proportional-integral (PI) regulating torque of the motor based on the target PI control strategy includes:

[0018] When the target proportional-integral control strategy is the first proportional-integral control strategy, the current speed of the engine and the current speed difference between the current speed and the target idle speed are determined.

[0019] If the current speed difference exceeds the preset speed difference range, the boundary value closest to the current speed difference in the preset speed difference range shall be determined as the current speed difference;

[0020] The proportional-integral adjustment torque is determined based on the current rotational speed and the current rotational speed difference.

[0021] In one embodiment of this application, the step of determining the proportional-integral adjustment torque based on the current rotational speed and the current rotational speed difference includes:

[0022] Based on the current rotational speed and the current rotational speed difference, determine the proportional control coefficient and the integral control coefficient;

[0023] Based on the current speed difference and the proportional adjustment coefficient, the proportional adjustment torque is determined; based on the current speed difference and the integral adjustment coefficient, the integral adjustment torque is determined.

[0024] The proportional-integral adjustment torque is determined based on the proportional adjustment torque and the integral adjustment torque.

[0025] In one embodiment of this application, the step of determining the compensation torque of the motor based on the current speed difference between the current engine speed and the target idle speed includes:

[0026] Based on the latest compensation torque lookup table, the compensation torque corresponding to the current speed difference is determined; the latest compensation torque lookup table is obtained based on the self-learning algorithm triggered last time, and the compensation torque lookup table is used to characterize different compensation torques under different speed differences.

[0027] In one embodiment of this application, before the step of determining the compensation torque corresponding to the current speed difference based on the latest compensation torque lookup table, the method further includes:

[0028] When the engine is detected to have entered a stable idling state, a first maximum speed difference between the first maximum speed of the engine and the target idling speed is determined;

[0029] If the first maximum speed difference is greater than the self-learning adjustment threshold, the self-learning algorithm is triggered, and the first compensation torque corresponding to the first maximum speed is determined based on the initial compensation torque lookup table.

[0030] Based on the current motor execution torque of the motor and the first compensation torque, the target motor execution torque is determined; and after controlling the motor to output torque according to the target motor execution torque, the second maximum speed difference between the second maximum speed of the engine and the target idle speed is determined;

[0031] If the second maximum speed difference is still greater than the self-learning adjustment threshold, a second maximum speed difference between the second maximum speed and the self-learning adjustment threshold is determined;

[0032] Based on the initial compensation torque lookup table, determine the second compensation torque corresponding to the second maximum speed difference;

[0033] The compensation torque corresponding to the first maximum speed is updated from the first compensation torque to the sum of the second compensation torque and the first compensation torque, so as to update the initial compensation torque lookup table to the latest compensation torque lookup table.

[0034] In one embodiment of this application, the method further includes:

[0035] When the power battery has a charging requirement, determine the charging torque of the motor;

[0036] Based on the proportional-integral adjustment torque, the compensation torque, and the charging torque, the second motor execution torque of the motor is determined, and the motor is controlled to output torque according to the second motor execution torque;

[0037] Based on the charging torque, a first engine execution torque is determined for the engine, and the engine is controlled to output torque according to the first engine execution torque.

[0038] In one embodiment of this application, after determining the charging torque of the motor when the power battery has a charging demand, the method further includes:

[0039] When the vehicle is in crawl mode, determine the crawl drive torque of the engine;

[0040] Based on the charging torque and the creep drive torque, the second engine execution torque of the engine is determined, and the engine is controlled to output torque according to the second engine execution torque.

[0041] Secondly, based on the same inventive concept, embodiments of this application provide an engine idle speed control device for a hybrid vehicle, the device comprising:

[0042] The control strategy determination module is used to determine the target proportional-integral control strategy corresponding to the triggering mode based on the triggering mode of the engine's idling condition; wherein, different triggering modes correspond to different proportional-integral control strategies.

[0043] The torque adjustment determination module is used to determine the proportional-integral adjustment torque of the motor based on the target proportional-integral control strategy.

[0044] The compensation torque determination module is used to determine the compensation torque of the motor based on the current speed difference between the current speed of the engine and the target idle speed.

[0045] The motor torque control module is used to determine the first motor execution torque of the motor based on the proportional-integral adjustment torque and the compensation torque, and control the motor to output torque according to the first motor execution torque to adjust the current speed of the engine.

[0046] In one embodiment of this application, the control strategy determination module includes:

[0047] The first strategy determination submodule is used to determine the target proportional-integral control strategy as a first proportional-integral control strategy when the triggering method is detected as the driver releasing the accelerator pedal; the first proportional-integral control strategy is a strategy that limits the rate of change of the current speed.

[0048] The second strategy determination submodule is used to determine the target proportional-integral control strategy as the second proportional-integral control strategy when the triggering method is not the driver releasing the accelerator pedal; the second proportional-integral control strategy is a strategy that does not limit the rate of change of the current speed.

[0049] In one embodiment of this application, the adjusting torque determining module includes:

[0050] The first speed information determination submodule is used to determine the current speed of the engine and the current speed difference between the current speed and the target idle speed when the target proportional-integral control strategy is the second proportional-integral control strategy.

[0051] The first regulating torque determination submodule is used to determine the proportional-integral regulating torque based on the current speed and the current speed difference.

[0052] In one embodiment of this application, the adjusting torque determining module further includes:

[0053] The second speed information determination submodule is used to determine the current speed of the engine and the current speed difference between the current speed and the target idle speed when the target proportional-integral control strategy is the first proportional-integral control strategy.

[0054] The speed difference limiting submodule is used to determine the current speed difference as the boundary value closest to the current speed difference in the preset speed difference range when the current speed difference exceeds the preset speed difference range;

[0055] The second regulating torque determination submodule is used to determine the proportional-integral regulating torque based on the current speed and the current speed difference.

[0056] In one embodiment of this application, both the first adjustment torque determining submodule and the second adjustment torque determining submodule include:

[0057] The coefficient determination unit is used to determine the proportional adjustment coefficient and the integral adjustment coefficient based on the current rotational speed and the current rotational speed difference.

[0058] The first torque determination unit is used to determine the proportional adjustment torque based on the current speed difference and the proportional adjustment coefficient; and to determine the integral adjustment torque based on the current speed difference and the integral adjustment coefficient.

[0059] The second torque determination unit is used to determine the proportional-integral adjustment torque based on the proportional adjustment torque and the integral adjustment torque.

[0060] In one embodiment of this application, the compensation torque determination module includes:

[0061] The compensation torque comparison submodule is used to determine the compensation torque corresponding to the current speed difference based on the latest compensation torque comparison table; the latest compensation torque comparison table is obtained based on the self-learning algorithm triggered last time, and the compensation torque comparison table is used to characterize different compensation torques under different speed differences.

[0062] In one embodiment of this application, the engine idle speed control device for the hybrid vehicle further includes:

[0063] The first maximum speed difference determination module is used to determine the first maximum speed difference between the first maximum speed of the engine and the target idle speed when the engine is detected to have entered a stable idling state.

[0064] The first compensation torque determination module is used to trigger the self-learning algorithm when the first maximum speed difference is greater than the self-learning adjustment threshold, and determine the first compensation torque corresponding to the first maximum speed based on the initial compensation torque lookup table.

[0065] The second maximum speed difference determination module is used to determine the second maximum speed difference between the second maximum speed and the self-learning adjustment threshold when the second maximum speed difference is detected to still be greater than the self-learning adjustment threshold.

[0066] The second compensation torque determination module is used to determine the second compensation torque corresponding to the second maximum speed difference based on the initial compensation torque lookup table.

[0067] The compensation torque lookup table update module is used to update the compensation torque corresponding to the first maximum speed from the first compensation torque to the sum of the second compensation torque and the first compensation torque, so as to update the initial compensation torque lookup table to the latest compensation torque lookup table.

[0068] In one embodiment of this application, the engine idle speed control device for the hybrid vehicle further includes:

[0069] A charging torque determination module is used to determine the charging torque of the motor when the power battery has a charging demand.

[0070] The second motor torque control module is used to determine the second motor execution torque of the motor based on the proportional-integral adjustment torque, the compensation torque and the charging torque, and control the motor to output torque according to the second motor execution torque;

[0071] The first engine torque control module is used to determine the first engine execution torque of the engine based on the charging torque, and control the engine to output torque according to the first engine execution torque.

[0072] In one embodiment of this application, the engine idle speed control device for the hybrid vehicle further includes:

[0073] A creep drive torque determination module is used to determine the creep drive torque of the engine when the vehicle is in creep mode.

[0074] The second engine torque control module is used to determine the second engine execution torque of the engine based on the charging torque and the creep drive torque, and control the engine to output torque according to the second engine execution torque.

[0075] Thirdly, based on the same inventive concept, embodiments of this application provide a storage medium storing machine-executable instructions, which, when executed by a processor, implement the engine idling speed control method for hybrid vehicles proposed in the first aspect of this application.

[0076] Fourthly, based on the same inventive concept, embodiments of this application provide a vehicle including a processor and a memory, wherein the memory stores machine-executable instructions that can be executed by the processor, and the processor is used to execute the machine-executable instructions to implement the engine idling speed control method for a hybrid vehicle proposed in the first aspect of this application.

[0077] Compared with the prior art, this application has the following advantages:

[0078] This application provides an engine idling speed control method for a hybrid vehicle. Based on the triggering mode of the engine's idling condition, it determines the target proportional-integral (PI) control strategy corresponding to the triggering mode, and determines the proportional-integral (PI) adjustment torque of the electric motor based on the target PI control strategy. Simultaneously, based on the current speed difference between the engine's current speed and the target idling speed, it determines the compensation torque of the electric motor. Furthermore, based on the PI adjustment torque and the compensation torque, it determines the first motor execution torque of the electric motor and controls the motor to output torque according to the first motor execution torque to adjust the engine's current speed. This application, by identifying the triggering mode of the engine's idling condition and matching corresponding PI control strategies to different triggering modes, can effectively meet the engine idling speed control requirements under various idling conditions. Moreover, based on PI adjustment and combined with the current speed difference of the engine, it can achieve torque compensation for the electric motor, thereby utilizing the electric motor's rapid response characteristics to achieve rapid and stable control of the engine's idling speed. Attached Figure Description

[0079] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0080] Figure 1 This is a flowchart of the steps of an engine idling speed control method for a hybrid vehicle according to an embodiment of this application.

[0081] Figure 2 This is a functional module diagram of an engine idle speed control device for a hybrid vehicle according to one embodiment of this application.

[0082] Figure 3 This is a structural schematic diagram of a vehicle according to one embodiment of this application. Detailed Implementation

[0083] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0084] It should be noted that hybrid vehicles are those powered by both an engine and a drive motor. The ratio of these two power sources is adjusted according to the vehicle's operating conditions to achieve energy savings and emission reductions. The powertrain systems of hybrid vehicles are complex, and their performance parameters undergo irreversible changes over time. Furthermore, the inconsistent states of different vehicles mean that a single PID control strategy will have significantly different effects at different times or under different idling conditions, making it difficult to achieve rapid and stable control of the engine idle speed under real-world vehicle conditions.

[0085] To address the problems existing in the background technology, this application aims to provide an engine idling speed control method for hybrid vehicles. By identifying the triggering mode of the engine idling condition and matching the corresponding proportional-integral control strategy for idling conditions with different triggering modes, the method can effectively meet the engine idling speed control requirements under various idling conditions. At the same time, based on the proportional-integral adjustment and combined with the current speed difference of the engine, torque compensation of the motor can be achieved, thereby utilizing the fast response characteristics of the motor to achieve fast and stable control of the engine idling speed.

[0086] Reference Figure 1This application illustrates an engine idling speed control method for a hybrid vehicle, which may include the following steps:

[0087] S101: Based on the triggering method of the engine idling condition, determine the target proportional-integral control strategy corresponding to the triggering method.

[0088] It should be noted that the executing entity in this embodiment can be a computing service device with data processing, network communication, and program execution functions, or an electronic device with the above functions, such as a vehicle computer or in-vehicle computer. This embodiment will use a VCU (Vehicle Controller Unit) as the executing entity for description. It should also be noted that this embodiment does not impose specific restrictions on the executing entity of the vehicle.

[0089] In this embodiment, considering the complex operating conditions of vehicles, there are multiple operating conditions that require the vehicle to enter an idling state. For example, the VCU can respond to the driver's accelerator pedal operation to control the vehicle to enter an idling state; it can also control the engine to automatically enter an idling state according to a preset vehicle control strategy, such as when the vehicle starts or in intelligent start-stop mode, where there are situations where it is necessary to control the engine to temporarily enter an idling state. Therefore, to effectively meet the engine idling control requirements under various idling conditions, corresponding proportional-integral (PI) control strategies will be matched for idling conditions with different triggering methods. In other words, different triggering methods correspond to different PPI control strategies.

[0090] S102: Determine the proportional-integral adjustment torque of the motor based on the target proportional-integral control strategy.

[0091] In this embodiment, the target proportional-integral control strategy belongs to PI control (proportional-integral control). By executing the target proportional-integral control strategy, the target proportional-integral control strategy can calculate in real time the proportional-integral adjustment torque required by the motor output. This proportional-integral adjustment torque is used to control the engine speed to maintain the target idle speed.

[0092] S103: Determine the motor's compensation torque based on the current speed difference between the engine's current speed and the target idle speed.

[0093] In this embodiment, by monitoring the current speed difference, the engine speed fluctuation can be understood in real time, and when the engine speed fluctuation is large, the output torque of the motor can be compensated in a timely manner.

[0094] It should be noted that the compensation torque can be positive or negative. For example, when the proportional-integral regulating torque output by the motor is positive, if the current engine speed fluctuates above the target idle speed, the corresponding compensation torque can be negative to reduce the torque applied by the motor to the engine, thereby reducing the engine speed. Conversely, if the current engine speed fluctuates below the target idle speed, the corresponding compensation torque can be positive to increase the torque applied by the motor to the engine, thereby increasing the engine speed.

[0095] S104: Based on the proportional-integral adjustment torque and the compensation torque, determine the first motor execution torque of the motor, and control the motor to output torque according to the first motor execution torque to adjust the current speed of the engine.

[0096] In a specific implementation, after calculating the proportional-integral (PI) regulating torque and the compensation torque, the VCU determines the sum of the PI regulating torque and the compensation torque as the first motor execution torque, and sends a motor control command containing the first motor execution torque to the motor controller, so that the motor controller responds to the motor control command and outputs torque according to the first motor execution torque.

[0097] In this embodiment, the motor and engine are connected and located on the same side of the vehicle, such as the front or rear axle. Specifically, the motor can be a drive motor or an integrated starter-generator (ISG) motor. When the motor is a drive motor, it is connected to one end of the input shaft, and the other end of the input shaft is connected to the engine via a clutch. Therefore, the first motor torque output by the drive motor can be transmitted to the engine through the input shaft and the clutch to regulate the engine speed. When the motor is an ISG motor, it is located at the crankshaft end of the engine and integrated with the crankshaft. Therefore, the ISG motor can directly drive the crankshaft to rotate, thereby regulating the engine speed.

[0098] In this embodiment, by identifying the triggering method of the engine's idling condition and matching the corresponding proportional-integral control strategy for the idling condition with different triggering methods, the engine idling control requirements under various idling conditions can be effectively met. At the same time, based on the proportional-integral adjustment and combined with the current speed difference of the engine, torque compensation of the motor can be achieved, and by utilizing the fast response characteristics of the motor, fast and stable control of the engine idling speed can be achieved.

[0099] In one feasible implementation, S101 may specifically include the following sub-steps:

[0100] S101-1: When the triggering method is detected as the driver releasing the accelerator pedal, the target proportional-integral control strategy is determined to be the first proportional-integral control strategy.

[0101] In this embodiment, the first proportional-integral control strategy is a strategy that limits the rate of change of the current rotational speed.

[0102] In this embodiment, considering that when the driver releases the accelerator pedal at high engine speed, the current engine speed will drop to the target idle speed at a large rate of change, which does not meet the requirement of normal engine speed drop when the vehicle releases the accelerator pedal, and may easily bring a bad driving experience to the user, when it is detected that the engine idle condition is triggered by the driver releasing the accelerator pedal, in order to prevent the engine speed from dropping too quickly, the engine speed will be controlled according to the first proportional integral control strategy.

[0103] S101-2: If the triggering method is not the driver releasing the accelerator pedal, determine the target proportional-integral control strategy as the second proportional-integral control strategy.

[0104] In this embodiment, the second proportional-integral control strategy is a strategy that does not limit the rate of change of the current rotational speed.

[0105] In this embodiment, if the engine idling condition is not triggered by the driver releasing the accelerator pedal, it indicates that this is a normal speed regulation process and there is no need to limit the rate of change of the current speed. Therefore, the engine speed is controlled according to the second proportional-integral control strategy.

[0106] In one feasible implementation, S102 may specifically include the following sub-steps:

[0107] S102-A1: When the target proportional-integral control strategy is the second proportional-integral control strategy, determine the current engine speed and the current speed difference between the current speed and the target idle speed.

[0108] In this embodiment, after determining that the target proportional-integral control strategy is the second proportional-integral control strategy, the VCU will collect the current engine speed and the current speed difference between the current speed and the target idle speed in real time, and perform PI control according to the second proportional-integral control strategy.

[0109] S102-A2: Determine the proportional-integral adjustment torque based on the current speed and the current speed difference.

[0110] In this embodiment, the VCU is equipped with a proportional controller and an integral controller. By inputting the current speed and the current speed difference into the proportional controller, a proportional regulating torque can be output. By inputting the current speed and the current speed difference into the integral controller, an integral regulating torque can be output. Then, based on the proportional regulating torque and the integral regulating torque, the proportional-integral regulating torque is determined.

[0111] In a specific implementation, S102-A2 may include the following sub-steps:

[0112] S102-A2-1: Determine the proportional control coefficient and integral control coefficient based on the current speed and the current speed difference.

[0113] In this embodiment, the VCU pre-stores a proportional calibration MAP and a differential calibration MAP. The proportional calibration MAP represents different proportional adjustment coefficients corresponding to different speeds and different current speed differences, while the differential calibration MAP represents different integral adjustment coefficients corresponding to different speeds and different current speed differences. These proportional and differential calibration MAPs can be obtained through calibration experiments.

[0114] In the specific implementation, after the VCU obtains the current speed and the current speed difference, it can query the proportional adjustment coefficient corresponding to the current speed and the current speed difference through the proportional calibration MAP; and query the integral adjustment coefficient corresponding to the current speed and the current speed difference through the differential calibration MAP.

[0115] S102-A2-2: Determine the proportional adjustment torque based on the current speed difference and the proportional adjustment coefficient; determine the integral adjustment torque based on the current speed difference and the integral adjustment coefficient.

[0116] In practice, the proportional torque is obtained by multiplying the current speed difference by the proportional adjustment coefficient; the integral torque is obtained by multiplying the current speed difference by the integral adjustment coefficient.

[0117] S102-A2-3: Determine the proportional-integral regulating torque based on the proportional regulating torque and the integral regulating torque.

[0118] In practice, the proportional adjustment torque and the integral adjustment torque are added together, and the sum is the required proportional-integral adjustment torque.

[0119] In one feasible implementation, S102 may further include the following sub-steps:

[0120] S102-B1: When the target proportional-integral control strategy is the first proportional-integral control strategy, determine the current engine speed and the current speed difference between the current speed and the target idle speed.

[0121] In this embodiment, after the VCU determines that the target proportional-integral control strategy is the first proportional-integral control strategy, it will also collect the current engine speed and the current speed difference between the current speed and the target idle speed in real time, and perform PI control according to the first proportional-integral control strategy.

[0122] S102-B2: When the current speed difference exceeds the preset speed difference range, the boundary value closest to the current speed difference in the preset speed difference range is determined as the current speed difference.

[0123] In this embodiment, considering that the current speed difference is large when the engine is at high speed, PI control based on this large speed difference would result in a large adjustment torque, causing the engine speed to drop rapidly. Therefore, by presetting the speed difference range, the current speed difference can be limited within the preset range.

[0124] For example, the preset speed difference range can be [-30rpm, 30rpm], so that when the current speed difference is greater than 30rpm, the current speed difference can be adjusted to 30rpm; or, when the current speed difference is less than -30rpm, the current speed difference can be adjusted to -30rpm.

[0125] S102-B3: Determine the proportional-integral adjustment torque based on the current speed and the current speed difference.

[0126] It should be noted that this step is the same as the sub-step shown in S102-A2, and the specific calculation process will not be described again here.

[0127] In one feasible implementation, S103 may specifically include the following sub-steps:

[0128] S103-1: Based on the latest compensation torque comparison table, determine the compensation torque corresponding to the current speed difference.

[0129] In this embodiment, considering that the power system of hybrid vehicles is relatively complex, the vehicle performance parameters will change irreversibly as the vehicle runs for a long time, and different vehicle states are inconsistent, a self-learning algorithm will be used to adaptively learn the compensation torque under different vehicle states in order to ensure the accuracy of engine speed control under different vehicle states, so as to achieve continuous updating of compensation torque.

[0130] It should be noted that the latest compensation torque lookup table is obtained based on the self-learning algorithm triggered last time. The compensation torque lookup table is used to characterize different compensation torques under different speed differences. In other words, after the VCU obtains the current speed difference, it can look up the compensation torque corresponding to the current speed difference through the latest compensation torque lookup table.

[0131] In one feasible implementation, prior to S103-1, the engine idling speed control method for hybrid vehicles may further include the following steps:

[0132] S103-2: When the engine is detected to have entered a stable idling state, determine the first maximum speed difference between the first maximum speed of the engine and the target idling speed.

[0133] In this embodiment, a timer can be triggered after the engine's current speed is detected to have reached the target idle speed. After the timer has been set for a preset duration, such as 1 second, the engine can be considered to have entered a stable idle state.

[0134] In this embodiment, after determining that the engine has entered a stable idling state, the speed difference between the engine speed and the target idling speed will continue to be detected. In a specific implementation, the speed difference can be monitored at preset time intervals, and the maximum speed difference generated during the monitoring period can be determined as the first maximum speed difference.

[0135] S103-3: When the first maximum speed difference is greater than the self-learning adjustment threshold, the self-learning algorithm is triggered, and the first compensation torque corresponding to the first maximum speed is determined based on the initial compensation torque lookup table.

[0136] In this embodiment, when the first maximum speed difference is detected to be greater than the self-learning adjustment threshold, it indicates that the engine speed fluctuates greatly when the first compensation torque corresponding to the first maximum speed difference is applied to the engine. At this time, the self-learning algorithm will be triggered to relearn the first compensation torque.

[0137] S103-4: Based on the current motor execution torque and the first compensation torque, determine the target motor execution torque; and after controlling the motor to output torque according to the target motor execution torque, determine the second maximum speed difference between the engine's second maximum speed and the target idle speed.

[0138] In this embodiment, the current motor torque will be supplemented by the first compensation torque. After the first compensation torque is supplemented, the engine speed difference will continue to be monitored to determine whether the engine speed still fluctuates significantly.

[0139] S103-5: If the second maximum speed difference is still greater than the self-learning adjustment threshold, determine the second maximum speed difference between the second maximum speed and the self-learning adjustment threshold.

[0140] In this embodiment, when the second maximum speed difference is detected to be greater than the self-learning adjustment threshold, it indicates that the selection of the first compensation torque is too small and the first compensation torque needs to be updated.

[0141] In practice, the VCU will calculate the second maximum speed difference between the second maximum speed and the self-learning adjustment threshold. This second maximum speed difference is the speed difference that the engine needs to be controlled to reduce.

[0142] S103-6: Based on the initial compensation torque lookup table, determine the second compensation torque corresponding to the second maximum speed difference.

[0143] In this embodiment, since the initial compensation torque lookup table is used to characterize different compensation torques under different speed differences, that is, it provides the torque values ​​that need to be supplemented under different speed differences, the second compensation torque corresponding to the second maximum speed difference can be determined based on the initial compensation torque lookup table. This second compensation torque is the torque that needs to be supplemented based on the first compensation torque.

[0144] S103-7: Update the compensation torque corresponding to the first maximum speed from the first compensation torque to the sum of the second compensation torque and the first compensation torque, so as to update the initial compensation torque lookup table to the latest compensation torque lookup table.

[0145] In this embodiment, by supplementing the first compensation torque with a second compensation torque, it is possible to make the engine speed fluctuation less than the self-learning adjustment threshold after applying the sum of the second compensation torque and the first compensation torque to the engine, thereby maintaining the engine speed within a small fluctuation range.

[0146] In one example, the self-learning adjustment threshold is 10 rpm. After the engine enters a stable idling state, the first maximum speed difference is detected to be 30 rpm, which is greater than the self-learning adjustment threshold of 10 rpm. This triggers the self-learning algorithm. Since the first compensation torque corresponding to 30 rpm is 5 N in the initial compensation torque lookup table, the current motor torque will be supplemented according to 5 N. The second maximum speed difference is detected to be 20 rpm, which is still greater than the self-learning adjustment threshold of 10 rpm. At this time, the second maximum speed difference between the second maximum speed of 20 rpm and the self-learning adjustment threshold of 10 rpm is calculated to be 10 rpm. Through the initial compensation torque lookup table, it can be found that the second compensation torque corresponding to 10 rpm is 2 N. The compensation torque corresponding to 30 rpm is updated from 5 N to 5 N + 2 N = 7 N. Then, the initial compensation torque lookup table is updated to the latest compensation torque lookup table.

[0147] In one feasible implementation, the engine idle speed control method for hybrid vehicles may further include the following steps:

[0148] S201: Determine the charging torque of the motor when the power battery has a charging requirement.

[0149] It should be noted that the motor is also connected to the power battery, so when the motor needs to output positive torque, the power battery can act as a power source to output electrical energy; when the power battery needs to be charged, the motor can act as a generator to charge the power battery by outputting negative torque.

[0150] In this embodiment, in order to meet the charging needs of the power battery when the vehicle is idling, the VCU will determine the charging torque of the motor based on the charging needs of the power battery.

[0151] S202: Based on the proportional-integral adjustment torque, compensation torque, and charging torque, determine the second motor execution torque of the motor, and control the motor to output torque according to the second motor execution torque.

[0152] In this embodiment, when the power battery has a charging demand, the charging torque of the power battery will be further considered, and the sum of the proportional-integral adjustment torque, the compensation torque and the charging torque will be determined as the execution torque of the second motor, so as to control the motor to output torque according to the execution torque of the second motor.

[0153] S2023: Based on the charging torque, determine the first engine execution torque of the engine, and control the engine to output torque according to the first engine execution torque.

[0154] In this embodiment, in order to meet the charging requirements of the power battery, the VCU will control the engine to output a first engine execution torque corresponding to the charging torque, thereby effectively meeting the charging requirements of the power battery while the motor controls the engine speed.

[0155] In one feasible implementation, after S201, the engine idle speed control method for hybrid vehicles may further include the following steps:

[0156] S301: Determine the engine's creep drive torque when the vehicle is in creep mode.

[0157] It should be noted that in crawl mode, the vehicle can automatically brake and output torque, allowing it to traverse rough terrain at a very slow speed. In practical applications, crawl mode eliminates the need for driver intervention with the accelerator and brakes; the vehicle can be controlled autonomously and can release torque based on road conditions, electronically distributing braking force to all four wheels to prevent wheel slippage.

[0158] In this embodiment, to ensure that the vehicle can drive normally in crawl mode, the engine's crawl drive torque will be obtained based on the vehicle's required torque, so that the engine can smoothly drive the vehicle to crawl.

[0159] S302: Based on the charging torque and creep drive torque, determine the second engine execution torque of the engine, and control the engine to output torque according to the second engine execution torque.

[0160] In practice, the sum of the charging torque and the creep drive torque can be used to determine the engine's second engine execution torque. By controlling the engine to output torque according to the second engine execution torque, not only can the charging needs of the power battery be met, but the creep needs of the vehicle can also be effectively met.

[0161] Secondly, based on the same inventive concept, and referring to... Figure 2 This application provides an engine idle speed control device 200 for a hybrid vehicle, which includes:

[0162] The control strategy determination module 201 is used to determine the target proportional-integral (PI) control strategy corresponding to the triggering method based on the engine's idling condition. Different triggering methods correspond to different PPI control strategies.

[0163] The torque adjustment determination module 202 is used to determine the proportional-integral adjustment torque of the motor based on the target proportional-integral control strategy.

[0164] The compensation torque determination module 203 is used to determine the compensation torque of the motor based on the current speed difference between the current engine speed and the target idle speed.

[0165] The motor torque control module 204 is used to determine the first motor execution torque of the motor based on proportional-integral adjustment torque and compensation torque, and control the motor to output torque according to the first motor execution torque to adjust the current speed of the engine.

[0166] In one feasible implementation, the control strategy determination module 201 includes:

[0167] The first strategy determination submodule is used to determine the target proportional-integral (PI) control strategy as the first PPI control strategy when the triggering method is detected as the driver releasing the accelerator pedal. The first PPI control strategy is a strategy that limits the rate of change of the current engine speed.

[0168] The second strategy determination submodule is used to determine the target proportional-integral (PI) control strategy as the second PPI control strategy when the triggering method is not detected as the driver releasing the accelerator pedal. The second PPI control strategy is a strategy that does not limit the rate of change of the current engine speed.

[0169] In one feasible implementation, the torque determination module 202 includes:

[0170] The first speed information determination submodule is used to determine the current speed of the engine and the current speed difference between the current speed and the target idle speed when the target proportional-integral control strategy is the second proportional-integral control strategy.

[0171] The first regulating torque determination submodule is used to determine the proportional-integral regulating torque based on the current speed and the current speed difference.

[0172] In one feasible implementation, the torque determination module 202 further includes:

[0173] The second speed information determination submodule is used to determine the current speed of the engine and the current speed difference between the current speed and the target idle speed when the target proportional-integral control strategy is the first proportional-integral control strategy.

[0174] The speed difference limiting submodule is used to determine the current speed difference as the boundary value closest to the current speed difference in the preset speed difference range when the current speed difference exceeds the preset speed difference range.

[0175] The second regulating torque determination submodule is used to determine the proportional-integral regulating torque based on the current speed and the current speed difference.

[0176] In one feasible implementation, both the first regulating torque determination submodule and the second regulating torque determination submodule include:

[0177] The coefficient determination unit is used to determine the proportional control coefficient and the integral control coefficient based on the current speed and the current speed difference.

[0178] The first torque determination unit is used to determine the proportional adjustment torque based on the current speed difference and the proportional adjustment coefficient; and to determine the integral adjustment torque based on the current speed difference and the integral adjustment coefficient.

[0179] The second torque determination unit is used to determine the proportional-integral adjustment torque based on the proportional adjustment torque and the integral adjustment torque.

[0180] In one feasible implementation, the compensation torque determination module 203 includes:

[0181] The compensation torque comparison submodule is used to determine the compensation torque corresponding to the current speed difference based on the latest compensation torque comparison table. The latest compensation torque comparison table is obtained based on the self-learning algorithm triggered last time, and the compensation torque comparison table is used to characterize different compensation torques under different speed differences.

[0182] In one feasible implementation, the engine idle speed control device for the hybrid vehicle further includes:

[0183] The first maximum speed difference determination module is used to determine the first maximum speed difference between the engine's first maximum speed and the target idle speed when the engine is detected to have entered a stable idling state.

[0184] The first compensation torque determination module is used to trigger a self-learning algorithm and determine the first compensation torque corresponding to the first maximum speed when the first maximum speed difference is greater than the self-learning adjustment threshold.

[0185] The second maximum speed difference determination module is used to determine the second maximum speed difference between the second maximum speed and the self-learning adjustment threshold when the second maximum speed difference is detected to still be greater than the self-learning adjustment threshold.

[0186] The second compensation torque determination module is used to determine the second compensation torque corresponding to the second maximum speed difference based on the initial compensation torque lookup table.

[0187] The compensation torque lookup table update module is used to update the compensation torque corresponding to the first maximum speed from the first compensation torque to the sum of the second compensation torque and the first compensation torque, so as to update the initial compensation torque lookup table to the latest compensation torque lookup table.

[0188] In one feasible implementation, the engine idle speed control device 200 of the hybrid vehicle further includes:

[0189] The charging torque determination module is used to determine the charging torque of the motor when the power battery has a charging requirement.

[0190] The second motor torque control module is used to determine the second motor execution torque of the motor based on the proportional-integral adjustment torque, compensation torque and charging torque, and control the motor to output torque according to the second motor execution torque.

[0191] The first engine torque control module is used to determine the first engine execution torque of the engine based on the charging torque, and control the engine to output torque according to the first engine execution torque.

[0192] In one feasible implementation, the engine idle speed control device 200 of the hybrid vehicle further includes:

[0193] The creep drive torque determination module is used to determine the engine's creep drive torque when the vehicle is in creep mode.

[0194] The second engine torque control module is used to determine the second engine execution torque of the engine based on the charging torque and the creep drive torque, and control the engine to output torque according to the second engine execution torque.

[0195] It should be noted that the specific implementation of the hybrid vehicle engine idle speed control device 200 in this application embodiment refers to the specific implementation of the hybrid vehicle engine idle speed control method proposed in the first aspect of the above-mentioned application embodiment, and will not be repeated here.

[0196] Thirdly, based on the same inventive concept, embodiments of this application provide a storage medium storing machine-executable instructions, which, when executed by a processor, implement the engine idling speed control method for hybrid vehicles proposed in the first aspect of this application.

[0197] It should be noted that the specific implementation of the storage medium in the embodiments of this application refers to the specific implementation of the engine idling speed control method for hybrid vehicles proposed in the first aspect of this application, and will not be repeated here.

[0198] Fourthly, based on the same inventive concept, referring to Figure 3 This application provides a vehicle 300, including a processor 301 and a memory 302; the memory 302 stores machine-executable instructions that can be executed by the processor 301, and the processor 301 is used to execute the machine-executable instructions to implement the engine idling speed control method for hybrid vehicles proposed in the first aspect of this application.

[0199] It should be noted that the specific implementation of the vehicle 300 in this application embodiment refers to the specific implementation of the engine idle speed control method for hybrid vehicles proposed in the first aspect of this application, and will not be repeated here.

[0200] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, apparatus, or computer program products. Therefore, embodiments of the present invention can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects. Furthermore, embodiments of the present invention can take the form of computer program products implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0201] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0202] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0203] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal equipment, causing a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0204] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present invention.

[0205] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes the element.

[0206] The present invention provides a detailed description of an engine idling speed control method, device, storage medium, and vehicle for a hybrid vehicle. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, those skilled in the art will recognize that there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. An engine idle control method of a hybrid vehicle, characterized by, The method includes: Based on the triggering method of the engine idling condition, a target proportional-integral control strategy corresponding to the triggering method is determined; wherein, the triggering method is whether the driver releases the accelerator pedal or not the driver releases the accelerator pedal, and different triggering methods correspond to different proportional-integral control strategies. Based on the target proportional-integral control strategy, the proportional-integral adjustment torque of the motor is determined; The compensation torque of the motor is determined based on the current speed difference between the current speed of the engine and the target idle speed. Based on the proportional-integral adjustment torque and the compensation torque, the first motor execution torque of the motor is determined, and the motor is controlled to output torque according to the first motor execution torque to adjust the current speed of the engine.

2. The engine idling speed control method for hybrid vehicles according to claim 1, characterized in that, The step of determining the target proportional-integral control strategy corresponding to the triggering mode based on the engine's idling condition includes: When the triggering method is detected as the driver releasing the accelerator pedal, the target proportional-integral control strategy is determined to be a first proportional-integral control strategy; the first proportional-integral control strategy is a strategy that limits the rate of change of the current speed. If the triggering method is not the driver releasing the accelerator pedal, the target proportional-integral control strategy is determined to be the second proportional-integral control strategy; the second proportional-integral control strategy is a strategy that does not limit the rate of change of the current speed.

3. The engine idle speed control method for hybrid vehicles according to claim 2, characterized in that, The steps for determining the proportional-integral (PI) regulating torque of the motor based on the target PI control strategy include: When the target proportional-integral control strategy is the second proportional-integral control strategy, the current speed of the engine and the current speed difference between the current speed and the target idle speed are determined; The proportional-integral adjustment torque is determined based on the current rotational speed and the current rotational speed difference.

4. The engine idle speed control method for hybrid vehicles according to claim 2, characterized in that, The steps for determining the proportional-integral (PI) regulating torque of the motor based on the target PI control strategy include: When the target proportional-integral control strategy is the first proportional-integral control strategy, the current speed of the engine and the current speed difference between the current speed and the target idle speed are determined. If the current speed difference exceeds the preset speed difference range, the boundary value closest to the current speed difference in the preset speed difference range shall be determined as the current speed difference; The proportional-integral adjustment torque is determined based on the current rotational speed and the current rotational speed difference.

5. The engine idling speed control method for hybrid vehicles according to claim 3 or 4, characterized in that, The step of determining the proportional-integral adjustment torque based on the current rotational speed and the current rotational speed difference includes: Based on the current rotational speed and the current rotational speed difference, determine the proportional control coefficient and the integral control coefficient; Based on the current speed difference and the proportional adjustment coefficient, the proportional adjustment torque is determined; based on the current speed difference and the integral adjustment coefficient, the integral adjustment torque is determined. The proportional-integral adjustment torque is determined based on the proportional adjustment torque and the integral adjustment torque.

6. The engine idling speed control method for hybrid vehicles according to claim 1, characterized in that, The step of determining the compensation torque of the motor based on the current speed difference between the current engine speed and the target idle speed includes: Based on the latest compensation torque lookup table, the compensation torque corresponding to the current speed difference is determined; the latest compensation torque lookup table is obtained based on the self-learning algorithm triggered last time, and the compensation torque lookup table is used to characterize different compensation torques under different speed differences.

7. The engine idling speed control method for a hybrid vehicle according to claim 6, characterized in that, Before determining the compensation torque corresponding to the current speed difference based on the latest compensation torque lookup table, the method further includes: When the engine is detected to have entered a stable idling state, a first maximum speed difference between the first maximum speed of the engine and the target idling speed is determined; When the first maximum speed difference is greater than the self-learning adjustment threshold, the self-learning algorithm is triggered, and the first compensation torque corresponding to the first maximum speed is determined based on the initial compensation torque lookup table. Based on the current motor execution torque of the motor and the first compensation torque, the target motor execution torque is determined; and after controlling the motor to output torque according to the target motor execution torque, the second maximum speed difference between the second maximum speed of the engine and the target idle speed is determined; If the second maximum speed difference is still greater than the self-learning adjustment threshold, a second maximum speed difference between the second maximum speed and the self-learning adjustment threshold is determined; Based on the initial compensation torque lookup table, determine the second compensation torque corresponding to the second maximum speed difference; The compensation torque corresponding to the first maximum speed is updated from the first compensation torque to the sum of the second compensation torque and the first compensation torque, so as to update the initial compensation torque lookup table to the latest compensation torque lookup table.

8. The engine idling speed control method for hybrid vehicles according to claim 1, characterized in that, The method further includes: When the power battery has a charging requirement, determine the charging torque of the motor; Based on the proportional-integral adjustment torque, the compensation torque, and the charging torque, the second motor execution torque of the motor is determined, and the motor is controlled to output torque according to the second motor execution torque; Based on the charging torque, a first engine execution torque is determined for the engine, and the engine is controlled to output torque according to the first engine execution torque.

9. The engine idling speed control method for a hybrid vehicle according to claim 8, characterized in that, After determining the charging torque of the motor when the power battery has a charging requirement, the method further includes: When the vehicle is in crawl mode, determine the crawl drive torque of the engine; Based on the charging torque and the creep drive torque, the second engine execution torque of the engine is determined, and the engine is controlled to output torque according to the second engine execution torque.

10. A storage medium, characterized in that, The storage medium stores machine-executable instructions, which, when executed by a processor, implement the engine idling speed control method for a hybrid vehicle as described in any one of claims 1-9.

11. A vehicle, characterized in that, The device includes a processor and a memory, the memory storing machine-executable instructions that can be executed by the processor, the processor executing the machine-executable instructions to implement the engine idling speed control method for a hybrid vehicle as described in any one of claims 1-9.

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