Engine control method, device, apparatus, and storage medium

Abstract

The application discloses an engine control method, device and equipment and a storage medium, relates to the technical field of vehicle control, and the engine control method comprises the following steps: when an engine starting demand of a target vehicle exists, a target speed difference and a target torque change rate are acquired; a target synchronization state is determined according to the target speed difference and the target torque change rate; when the target synchronization state is a synchronization success state, gear shifting is performed according to a target gear instruction and a speed and torque adjusting instruction, and a gear shifting state is obtained; and when the gear shifting state is a gear shifting completion state, the engine of the target vehicle is started. In the process of EV (electric vehicle) driving, the engine is started in advance to transition when a large slope exists and a power deficiency scene occurs, the pure electric mode EV gear is transitioned to the ECVT (electrically controlled continuously variable transmission) gear, the engine is started, and the driving performance of the whole vehicle is improved by simultaneously driving the driving motor and the ECVT.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle control, in particular to an engine control method, device, equipment and storage medium. BACKGROUND

[0002] For a hybrid vehicle, engine start control generally starts the engine to charge or directly drives according to the driver's demand power, SOC power preservation demand, etc. The existing technology hybrid vehicle shift process mostly adopts power interruption shift (series-parallel), especially when the power battery power is low and the discharge power is limited, or the motor drive torque is limited, power interruption shift is particularly obvious. And under the working condition of low torque motor and insufficient battery discharge power, the problems of weak power or slow acceleration overtaking are prone to occur during highland slope acceleration overtaking. SUMMARY

[0003] The main purpose of the present application is to provide an engine control method, device, equipment and storage medium, which aims to solve the technical problems of weak power or slow acceleration overtaking during highland slope acceleration overtaking under the working condition of low torque motor and insufficient battery discharge power.

[0004] To achieve the above purpose, the present application provides an engine control method, which comprises:

[0005] When the target vehicle has an engine start demand, a target speed difference and a target torque change rate are obtained;

[0006] A target synchronization state is determined according to the target speed difference and the target torque change rate;

[0007] When the target synchronization state is a synchronization success state, a gear position is switched according to a target gear position instruction and a speed and torque adjusting instruction, and a gear position switching state is obtained;

[0008] When the gear position switching state is a gear position switching completion state, the engine of the target vehicle is started.

[0009] In an embodiment, before the target vehicle has an engine start demand, the target speed difference and the target torque change rate are obtained, further comprising:

[0010] When the target vehicle is in a power activated state and the current vehicle speed is greater than a vehicle speed threshold, a current motor speed, a current vehicle slope and a current wheel edge torque are obtained;

[0011] A corresponding current torque threshold is determined according to the current motor speed and the current vehicle slope;

[0012] When the current wheel edge torque is less than the current torque threshold, it is determined that the target vehicle has an engine start demand.

[0013] In an embodiment, the step of obtaining the current wheel-side torque comprises:

[0014] When the target vehicle is in the pure electric mode, determining a current battery torque according to a current battery power and a preset conversion strategy, and obtaining a motor limit torque;

[0015] Performing torque calculation according to the current battery torque and the motor limit torque to obtain the current wheel-side torque.

[0016] In an embodiment, the step of determining the target synchronization state according to the target speed difference and the target torque change rate comprises:

[0017] Comparing the target speed difference with a speed difference threshold to obtain a speed difference comparison result;

[0018] Comparing the target torque change rate with a torque change rate threshold to obtain a torque change rate comparison result;

[0019] When the speed difference comparison result is that the target speed difference is less than the speed difference threshold and the torque change rate comparison result is that the target torque change rate is less than the torque change rate threshold, determining that the target synchronization state is a synchronization success state;

[0020] When at least one of the speed difference comparison result is that the target speed difference is greater than or equal to the speed difference threshold and the torque change rate comparison result is that the target torque change rate is greater than or equal to the torque change rate threshold, determining that the target synchronization state is a synchronization failure state.

[0021] In an embodiment, the step of performing gear shifting according to the target gear instruction and the speed-torque adjusting instruction to obtain a gear shifting state comprises:

[0022] Determining a gear speed difference according to a target gear speed corresponding to the target gear instruction and a current gear speed;

[0023] Performing PID calculation according to the gear speed difference and the speed-torque adjusting instruction to obtain a speed demand torque;

[0024] Performing gear shifting without a clutch according to the speed demand torque to determine the gear shifting state.

[0025] In an embodiment, the step of performing gear shifting without a clutch according to the speed demand torque to determine the gear shifting state comprises:

[0026] Performing gear shifting according to the speed demand torque to obtain a gear shifting position;

[0027] Determining a target position difference according to the gear shifting position and a target gear position;

[0028] determining a gear shift state according to the target position difference and the position difference threshold.

[0029] In an embodiment, the determining the gear shift state according to the target position difference and the position difference threshold comprises:

[0030] comparing the target position difference and the position difference threshold to obtain a position difference comparison result;

[0031] when the position difference comparison result is that the target position difference is less than the position difference threshold, determining the gear shift state as a gear shift completion state.

[0032] In addition, to achieve the above object, the present application further provides an engine control device, which comprises:

[0033] a processing module, configured to determine a target speed difference according to a gear ring speed and a synchronizer speed when a target vehicle has an engine start demand;

[0034] the processing module is further configured to determine a target synchronization state according to the target speed difference and a speed difference threshold;

[0035] the processing module is further configured to perform gear shift according to a target gear instruction and a speed regulation torque instruction when the target synchronization state is a synchronization success state, to obtain a gear shift state;

[0036] a starting module, configured to start the engine of the target vehicle when the gear shift state is a gear shift completion state.

[0037] In addition, to achieve the above object, the present application further provides an engine control device, which comprises: a memory, a processor and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the engine control method as described above.

[0038] In addition, to achieve the above object, the present application further provides a storage medium, which is a computer readable storage medium, and the storage medium stores a computer program, the computer program being executable by a processor to implement the steps of the engine control method as described above.

[0039] In addition, to achieve the above object, the present application further provides a computer program product, which comprises a computer program, the computer program being executable by a processor to implement the steps of the engine control method as described above.

[0040] The application determines a target speed difference according to the gear ring speed and the synchronizer speed when the target vehicle has an engine starting demand; determines a target synchronization state according to the target speed difference and a speed difference threshold; when the target synchronization state is a synchronization success state, performs gear shifting according to a target gear instruction and a speed regulation torque instruction, and obtains a gear shifting state; and when the gear shifting state is a gear shifting completion state, starts the engine of the target vehicle. In the process of EV (electric vehicle) driving, when a large slope exists, the engine is started in advance to transition from the pure electric mode EV gear to the ECVT (electrically controlled continuously variable transmission) gear, the engine is started, and the driving performance of the vehicle is improved by relying on the driving motor and the ECVT. BRIEF DESCRIPTION OF DRAWINGS

[0041] The drawings incorporated into the specification and forming a part thereof, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the application.

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, for those skilled in the art, other drawings can also be obtained without creative labor based on these drawings.

[0043] Figure 1 A flowchart is provided for the engine control method embodiment one of the present application;

[0044] Figure 2 A speed regulation request torque calculation flowchart is provided for the engine control method embodiment one of the present application;

[0045] Figure 3 A gear shifting flowchart is provided for the engine control method embodiment one of the present application;

[0046] Figure 4 A flowchart is provided for the engine control method embodiment two of the present application;

[0047] Figure 5 A schematic diagram of the corresponding relationship between the motor speed and the motor starting torque threshold at different slopes is provided for the engine control method embodiment two of the present application;

[0048] Figure 6 An engine starting demand judgment flowchart is provided for the engine control method embodiment two of the present application;

[0049] Figure 7 A schematic diagram of the overall control mode is provided for the engine control method embodiment two of the present application;

[0050] Figure 8 Brief flowchart of engine control method provided for embodiment two of the application;

[0051] Figure 9 Module structure diagram of engine control device provided for embodiment of the application;

[0052] Figure 10 Device structure diagram of hardware running environment involved in engine control method in embodiment of the application.

[0053] The purposes, functional features and advantages of the application will be further explained in combination with embodiments and with reference to the drawings. DETAILED DESCRIPTION

[0054] It should be understood that the specific embodiments described herein are merely intended to explain the technical solutions of the application, and are not used to limit the application.

[0055] In order to better understand the technical solutions of the application, the following will be described in detail in combination with the drawings of the specification and specific embodiments.

[0056] The main solution of the embodiment of the application is: when there is an engine starting demand for a target vehicle, a target speed difference and a target torque change rate are obtained; a target synchronization state is determined according to the target speed difference and the target torque change rate; when the target synchronization state is a synchronization success state, gear shifting is performed according to a target gear instruction and a speed and torque adjusting instruction, and a gear shifting state is obtained; when the gear shifting state is a gear shifting completion state, the engine of the target vehicle is started.

[0057] For a hybrid electric vehicle, engine starting control generally starts the engine to charge or directly drives according to the driver's demand power, SOC power demand, etc.; the existing technology hybrid electric vehicle shifting process mostly adopts power interruption shifting (series-parallel), especially when the power battery power is low and the discharge power is limited, or the motor driving torque is limited, power interruption shifting is particularly obvious, and under the condition of low torque motor and insufficient battery discharge power, highland slope acceleration overtaking is prone to problems such as weak power or slow acceleration overtaking.

[0058] This application determines a target speed difference based on the gear ring speed and synchronizer speed when the target vehicle requires engine starting; determines a target synchronization state based on the target speed difference and a speed difference threshold; when the target synchronization state is a successful synchronization state, performs gear switching according to the target gear command and speed and torque adjustment command to obtain a gear switching state; when the gear switching state is a completed gear switching state, starts the engine of the target vehicle. By transitioning the pure electric mode EV gear to ECVT (electronically controlled continuously variable transmission) gear during EV (electric vehicle) driving, which may involve steep inclines causing insufficient power, and starting the engine in advance, the engine is started. The system relies on the simultaneous drive of the drive motor and ECVT to improve the overall vehicle driving performance.

[0059] 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, such as a tablet computer, personal computer, or mobile phone, or an engine control device capable of performing the above functions. The following description uses an engine control device as the executing entity to illustrate this embodiment and the subsequent embodiments.

[0060] Based on this, embodiments of this application provide an engine control method, referring to... Figure 1 , Figure 1 This is a flowchart illustrating the first embodiment of the engine control method of this application.

[0061] In this embodiment, the engine control method includes steps S10 to S40:

[0062] Step S10: When the target vehicle has an engine starting requirement, obtain the target speed difference and the target torque change rate;

[0063] It should be noted that the power system of a hybrid vehicle generally consists of a drive motor, a generator, and an engine. These three power sources can be combined to output torque at the wheels to drive the vehicle, depending on the operating conditions. For example... Figure 2 As shown, the power source combination in this embodiment is a clutchless shifting system. By controlling the speed difference between the two ends of the synchronizer input shaft and output shaft and synchronizing the torque at the input end of the synchronizer with the acceleration of the torque at the output end of the synchronizer, the shift drum speed can be controlled to achieve shifting when the speed difference between the two ends of the synchronizer is less than a certain value and synchronized with the acceleration of the output torque at the two ends of the synchronizer. The timing of the gears is controlled by the VCU (vehicle control unit) and executed by the HTCU (hybrid transmission control unit) controller.

[0064] It should be noted that, in order to enable hybrid vehicles to operate in different modes, the hybrid transmission of hybrid vehicles can provide a variety of gears, and different gears can be matched with different power source combinations.

[0065] Exemplarily, the hybrid transmission of the embodiment of the application includes multiple gears, for example, the multiple gears are defined as gear 1 to gear 10, wherein gear 1 is a series gear, gear 2, gear 4, gear 8 and gear 10 are parallel direct drive gears, and gear 3, gear 5, gear 7 and gear 9 are ECVT gears. When gear 1, the engine continuously works in the high efficiency area after starting, the engine does not directly participate in driving, but powers the power battery through the generator, and the driving motor drives the whole vehicle as the power source of the whole vehicle. Gear 2, 4, 8 and 10 correspond to 1st gear, 2nd gear, 3rd gear and 4th gear direct drive gears respectively, wherein the speed ratio between the ring gear of the planetary gear set, the engine and the generator gradually decreases from gear 2 to gear 10, when gear 2 and gear 8, the engine participates in direct drive, the speed ratio between the ring gear, the engine and the generator is 1:1:1, the planetary gear is arranged as a whole, and can rely on the generator and the driving motor to generate electricity, when gear 4 and gear 10, the engine participates in direct drive, the GCU (motor controller) locks the torque, the speed is controlled at 0 RPM and 0 nm, and can rely on the driving motor to generate electricity. When gear 3, 5, 7 and 9, the engine needs to maintain the torque balance of the ring gear after starting, the generator speed, the engine speed and the ring gear speed need to maintain a fixed speed ratio relationship, the torque closed loop control can maintain the lever torque balance, and the smooth speed transition of the gear is realized. Therefore, the embodiment needs to engage S1 synchronizer when entering ECVT2_1 (gear 7) from EV (gear 6).

[0066] It can be understood that the target vehicle refers to a hybrid vehicle, the engine start demand is used to indicate the demand for starting the engine when the driving ability of the vehicle is insufficient, the target speed difference refers to the difference between the synchronizer speed and the ring gear speed, wherein the synchronizer speed refers to the current running speed of the synchronizer, the ring gear speed refers to the current speed of the ring gear in the planetary carrier, and the target torque change rate refers to the rate of change of torque with time, which is usually used to describe the increase or decrease of torque with time.

[0067] In specific implementation, when there is an engine start demand in the hybrid vehicle, it indicates that the current hybrid vehicle is insufficient in power, and then the difference between the ring gear speed in the planetary carrier and the current running speed of the synchronizer is calculated to obtain the target speed difference, and the rate of change of torque with time is calculated according to the speed change rate and the moment of inertia to obtain the target torque change rate, and then whether the synchronization condition is met, that is, whether the gear can be switched from EV (gear 6) to ECVT (gear 7) is determined according to the calculated difference between the synchronizer speed and the ring gear speed and the rate of change of torque with time.

[0068] Step S20, determining a target synchronization state according to the target speed difference and the target torque change rate;

[0069] It can be understood that the target synchronization state includes a synchronization success state and a synchronization failure state.

[0070] In a specific implementation, the synchronization condition in this embodiment is that the rotational speed difference is less than a threshold value and the torque change rate is less than a threshold value, and after the synchronization condition is met, the gear shifting is performed: if the torque change rate is higher than a certain threshold value, it is considered that the synchronization fails, and the gear shifting is performed in the reverse direction; or if the rotational speed difference of the synchronizer is greater than a certain threshold value, it is considered that the synchronization fails, and the gear shifting is performed in the reverse direction; the torque change rate calculation method is: GCU (Generator Control Unit for Range Extender Vehicles) angular velocity x moment of inertia = torque, angular velocity = rotational speed x 2π / 60, the rotational speed difference of the synchronizer: target rotational speed - actual rotational speed < a certain threshold value.

[0071] It should be noted that the monitoring principle of the torque change rate is the same as that of the rotational speed change rate: for the synchronization rotational speed difference condition: less than threshold value A is considered to meet synchronization condition 1, and greater than threshold value B is considered to not meet the synchronization condition, threshold value B = (A + Aoffset), Aoffset is generally positive, and in the process of the synchronization speed difference from A to B, it is considered that the synchronization condition is met; the current item boundary is determined by the synchronization capability of the synchronizer, A = 80 rpm, and B = 150 rpm; for the synchronization rotational speed change rate condition, the same principle is applied: less than threshold value ωC is considered to meet synchronization condition 1, and greater than threshold value ωD is considered to not meet the synchronization condition, threshold value ωD = (ωC + ωCoffset), ωCoffset is generally positive, and in the process of the synchronization speed difference from A to B, it is considered that the synchronization condition is met; when the rotational speed change rate and the synchronization speed difference are met at the same time, it is considered that the synchronization condition is met; C = 300 rpm / s 2 , D = 550 rpm / s 2 , J = 0.17, Torque ̇=J×ω.

[0072] In a possible implementation, the step S20 can include steps A21-A24:

[0073] In step A21, the target rotational speed difference and the rotational speed difference threshold value are compared to obtain a rotational speed difference comparison result.

[0074] It can be understood that the rotational speed difference comparison result refers to the comparison result of the target rotational speed difference and the rotational speed difference threshold value, and the rotational speed difference threshold value is used to judge the rotational speed difference critical value of the synchronization condition.

[0075] In a specific implementation, the target rotational speed difference and the rotational speed difference critical value used to judge whether the synchronization condition is met are compared to obtain a result that the target rotational speed difference is less than the rotational speed difference critical value used to judge whether the synchronization condition is met, or a result that the target rotational speed difference is greater than or equal to the rotational speed difference critical value used to judge whether the synchronization condition is met, that is, the rotational speed difference comparison result.

[0076] Step A22, compare the target torque change rate with the torque change rate threshold value to obtain a torque change rate comparison result;

[0077] It can be understood that the torque change rate comparison result refers to the comparison result of the target torque change rate and the torque change rate threshold value, and the torque change rate threshold value is used to judge the torque change rate critical value of whether the synchronization condition is met.

[0078] In specific implementation, the target speed difference and the speed difference critical value used to judge whether the synchronization condition is met are compared to obtain a result that the target torque change rate is less than the torque change rate critical value used to judge whether the synchronization condition is met, or a result that the target torque change rate is greater than or equal to the torque change rate critical value used to judge whether the synchronization condition is met, that is, the torque change rate comparison result.

[0079] Step A23, when the speed difference comparison result is that the target speed difference is less than the speed difference threshold value and the torque change rate comparison result is that the target torque change rate is less than the torque change rate threshold value, it is determined that the target synchronization state is a synchronization success state;

[0080] In specific implementation, when the speed difference comparison result is that the target speed difference is less than the speed difference critical value used to judge whether the synchronization condition is met, and the torque change rate comparison result is that the target torque change rate is less than the torque change rate threshold value, it indicates that the current speed difference and the torque change rate both meet the synchronization condition, and therefore, it is determined that the target synchronization state is a synchronization success state.

[0081] Step A24, when at least one of the speed difference comparison result is that the target speed difference is greater than or equal to the speed difference threshold value and the torque change rate comparison result is that the target torque change rate is greater than or equal to the torque change rate threshold value exists, it is determined that the target synchronization state is a synchronization failure state.

[0082] In specific implementation, when at least one of the speed difference comparison result is that the target speed difference is greater than or equal to the speed difference critical value used to judge whether the synchronization condition is met and the torque change rate comparison result is that the target torque change rate is greater than or equal to the torque change rate threshold value exists, it indicates that at least one of the current speed difference and the torque change rate does not meet the synchronization condition, and therefore, it is determined that the target synchronization state is a synchronization failure state.

[0083] It should be noted that the characteristics of picking up gears: the direct drive gear is shifted to the ECVT gear, or the ECVT gear is shifted to the EV gear, which is defined as picking up gears, and the condition of shifting the direct drive gear to the ECVT gear is that the planetary carrier torque needs to be balanced to pick up the S2 synchronizer, that is, M GEN +M ICE=0N·M, the current is less than 4.5N·M, allowing to shift out; the ECVT gear shifts to the EV gear condition: the planetary carrier torque needs to be kept at 0nm, i.e. the engine and the generator torque are both less than a threshold, so as to shift out the S1 synchronizer, and the planetary carrier torque needs to be kept balanced at 0N·M.

[0084] It should be noted that the gear engagement feature: the ECVT gear shifts to the direct drive gear, or the EV gear shifts to the ECVT gear, is defined as the gear engagement; the ECVT gear shifts to the direct drive gear condition: the torque change rate of the generator and the rotational speed difference between the two ends of the synchronizer are obtained; if the torque change rate is less than or equal to the change rate threshold, and the rotational speed difference between the two ends is less than or equal to the rotational speed difference threshold, it is determined that the target gear shifting synchronization condition is met. The EV gear shifts to the ECVT gear can be applicable, because the Ev hangs the ECVT, the engine is originally controlled at 0N·M, and the generator only has a speed regulating torque.

[0085] Step S30, when the target synchronization state is a synchronization success state, gear switching is performed according to the target gear instruction and the speed and torque adjusting instruction, to obtain a gear switching state;

[0086] It can be understood that the target gear instruction is an instruction indicating that the transmission should be switched to a specific gear, in this embodiment, the EV gear is switched to the ECVT power split gear, the speed and torque adjusting instruction is an instruction for adjusting the speed and torque during gear shifting, and the gear switching state includes a gear switching completion state and a gear switching failure state.

[0087] In specific implementation, when the target synchronization state is a synchronization success state, it indicates that the gear shifting condition is met, and the gear shifting operation can be performed, and then the gear switching is performed according to the instruction indicating that the transmission should be switched to a specific gear, i.e. the ECVT power split gear, and the instruction for adjusting the speed and torque during gear shifting, and finally, the gear switching state is obtained.

[0088] In a feasible implementation, step S30 can include steps A31-A33:

[0089] Step A31, determining a gear speed difference according to a target gear speed corresponding to the target gear instruction and a current gear speed;

[0090] It can be understood that the target gear speed refers to the speed of the target gear, the current gear speed refers to the speed of the current gear, and the gear speed difference refers to the difference between the speed of the target gear and the speed of the current gear.

[0091] In a specific implementation, the speed difference between the target gear and the current gear is calculated according to the speed corresponding to the target gear and the speed of the current gear, and then the speed difference between the speed corresponding to the target gear and the speed of the current gear is obtained according to the calculation result.

[0092] In step A32, PID calculation is performed according to the gear speed difference and the speed regulation torque instruction to obtain a speed regulation demand torque.

[0093] It can be understood that the speed regulation demand torque refers to the torque required to adjust the speed.

[0094] In a specific implementation, the speed difference needs to be kept less than a certain threshold during gear shifting, therefore, the torque required to adjust the speed is determined according to the calculation result by adjusting the speed and torque instructions and combining the PID calculation of the speed difference between the speed corresponding to the target gear and the speed of the current gear.

[0095] In step A33, the gear shifting without clutch is performed according to the speed regulation demand torque to determine the gear shifting state.

[0096] It can be understood that the speed control is performed by calculating the torque required to adjust the speed during gear shifting, and then the gear shifting state is determined.

[0097] In a feasible implementation, step A33 can include steps B331-B333.

[0098] In step B331, the gear shifting is performed according to the speed regulation demand torque to obtain a gear shifting position.

[0099] It can be understood that the gear shifting position refers to the position during the gear shifting.

[0100] In a specific implementation, the speed control is performed by adjusting the torque required to adjust the speed, i.e., shifting the gear, and the position during the gear shifting is obtained by monitoring the current position in real time during the gear shifting.

[0101] In step B332, a target position difference is determined according to the gear shifting position and the target gear position.

[0102] It can be understood that the target position difference refers to the difference between the position of the gear shifting and the position of the ECVT power split gear.

[0103] In step B333, the gear shifting state is determined according to the target position difference and a position difference threshold.

[0104] It can be understood that the position difference threshold is a position difference critical value for determining whether the gear shifting is completed.

[0105] In a specific implementation, the difference between the position of the gear shift and the position of the ECVT power split gear at the time of the gear shift is compared with a position difference threshold value for judging whether the gear shift is completed, and then the gear shift state is determined according to the comparison result.

[0106] In a possible implementation, the step B333 can include steps C3331-C3332.

[0107] In step C3331, the target position difference is compared with the position difference threshold value to obtain a position difference comparison result.

[0108] It can be understood that the position difference comparison result includes a result that the target position difference is less than the position difference threshold value and a result that the target position difference is greater than or equal to the position difference threshold value, and the position difference comparison result is used to determine whether the gear shift is completed.

[0109] In a specific implementation, the difference between the position of the gear shift and the position of the ECVT power split gear at the time of the gear shift is compared with a position difference threshold value for judging whether the gear shift is completed, and then the gear shift state is determined according to the comparison result.

[0110] In step C3332, when the position difference comparison result is that the target position difference is less than the position difference threshold value, it is determined that the gear shift state is a gear shift completion state.

[0111] It can be understood that when the position difference comparison result is that the difference between the position of the gear shift and the position of the ECVT power split gear at the time of the gear shift is less than the position difference threshold value for judging whether the gear shift is completed, it indicates that the current gear is the ECVT power split gear, that is, the gear shift is completed, and then it is determined that the gear shift state is a gear shift completion state.

[0112] In step S40, when the gear shift state is a gear shift completion state, the engine of the target vehicle is started.

[0113] It can be understood that when the gear shift state is a gear shift completion state, it indicates that the pure electric EV gear has been shifted to the ECVT power split gear, and then the engine of the hybrid electric vehicle is started to achieve the driving performance of the whole vehicle.

[0114] It should be noted that, as shown in FIG. 1, Figure 2 the gear ring speed N ring The target speed is the synchronizer speed N S1L (the synchronizer and the wheel shaft are connected together); based on N ring -N S1LThe speed difference (difference between the gear ring speed and the synchronizer speed) is adjusted by the GCU (range extender generator controller) torque and lever principle to adjust the gear ring speed; the GCU is maintained for speed closed loop control during the speed regulation process, and the HTCU (hybrid transmission control unit) feedbacks after the gear shifting is completed, exits the speed control, and enters the lever balanced torque control;

[0115] The engine maintains the fuel cut-off state and does not spray oil ignition; during the speed regulation process, the motor control mode is the speed control mode, and after the speed regulation is completed, the torque control mode and the speed control mode are entered.

[0116] It should be noted that, as shown in Figure 3 , the VECU serves as a central controller, mainly responsible for target gear instruction issuance, speed and torque regulation during gear shifting, and judgment of gear engagement and disengagement instructions; the VECU sets a part of the GCU torque M1 for adjusting the speed difference between the gear ring and the synchronizer, and a part of the torque M2 for balancing the planetary carrier; the M1 calculation method is: based on the speed difference between the two ends of the synchronizer, the P1 motor torque is obtained through PID regulation; the M2 calculation method is: Mg=1 / 3.6Me, wherein Mg is the generator torque and Me is the engine torque; the synchronization condition judgment: after the synchronization condition is met, the VECU engine instruction is executed by the MTCU (automatic transmission control unit); in order to maintain the synchronization process, the GCU speed needs to be continuously regulated, and the up and down limits of the speed regulation torque are limited; during the synchronization process, the synchronization is executed by the MTCU feedback gear shifting completion; finally, the switching from pure electric to ECVT power split gear is realized.

[0117] In this embodiment, when there is an engine start demand in the target vehicle, the target speed difference is determined according to the gear ring speed and the synchronizer speed; the target synchronization state is determined according to the target speed difference and the speed difference threshold; when the target synchronization state is a synchronization success state, the gear shifting is performed according to the target gear instruction and the speed and torque regulation instruction, and the gear shifting state is obtained; when the gear shifting state is a gear shifting completion state, the engine of the target vehicle is started. In the EV (electric vehicle) driving process, the engine is started in advance to transition from the pure electric mode EV gear to the ECVT (electrically controlled continuously variable transmission) gear in the case of a possible large slope, which causes power deficiency, so as to improve the driving performance of the whole vehicle by relying on the driving motor and the ECVT to drive at the same time.

[0118] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as the above embodiment one can refer to the above introduction, and will not be described in detail. On this basis, please refer to Figure 4 , before step S10, the engine control method further includes steps S01-S03:

[0119] Step S01, when the target vehicle is in a power activated state and the current vehicle speed is greater than a vehicle speed threshold, obtaining a current motor speed, a current vehicle slope, and a current wheel edge torque;

[0120] It can be understood that the current vehicle slope refers to the slope size where the vehicle is currently located, and the current wheel edge torque refers to the wheel edge torque size of the current vehicle.

[0121] In a specific implementation, when the hybrid vehicle is in a power activated state (ready) and the current driving speed is greater than a set speed threshold, it indicates that the condition for judging whether the vehicle has an engine start demand is met, and then the current motor operating speed, the slope size where the vehicle is currently located, and the current wheel edge torque size of the vehicle are obtained, and whether the vehicle has an engine start demand is determined according to the above data.

[0122] In a feasible implementation, step S01 can include steps A011-A012:

[0123] Step A011, when the target vehicle is in an electric mode, determining a current battery torque according to a current battery power and a preset conversion strategy, and obtaining a motor limit torque;

[0124] It can be understood that the current battery torque refers to the maximum torque corresponding to the available power of the battery, the motor limit torque refers to the maximum allowable torque value of the motor driving capability when accepting the torque capability limitation of the motor controller, and the preset conversion strategy refers to a strategy for pre-setting the torque size converted from the available power of the battery.

[0125] In a specific implementation, when the hybrid vehicle is in an electric driving mode, the corresponding torque is calculated according to the pre-set strategy for converting the torque size from the available power of the battery according to the current available power of the battery, to obtain the maximum torque corresponding to the available power of the battery, and then the maximum allowable torque value of the motor driving capability is obtained.

[0126] Step A012, performing torque calculation according to the current battery torque and the motor limit torque to obtain a current wheel edge torque.

[0127] It can be understood that the current battery torque and the motor limit torque are compared, and the torque with a smaller value is selected for wheel edge torque calculation, and then the current wheel edge torque is determined according to the transmission system reduction ratio, for example, the current battery torque is smaller than the motor limit torque, and therefore the wheel edge torque is calculated according to the maximum allowable torque value of the motor driving capability when accepting the torque capability limitation of the motor controller and the transmission system reduction ratio, i.e. the current wheel edge torque is obtained.

[0128] Step S02, determining a corresponding current torque threshold according to the current motor speed and the current vehicle slope;

[0129] It can be understood that the current torque threshold refers to a motor starting torque threshold, and the current torque threshold is used to determine whether the pure electric mode can drive the vehicle to normally travel at the current slope.

[0130] In a specific implementation, as shown in Figure 5 , according to the slope where the current vehicle is located and the current engine speed, the current torque threshold is obtained through the correspondence relationship between the slope, the speed and the motor starting torque threshold, and the correspondence relationship between the slope, the speed and the motor starting torque threshold can be obtained through vehicle calibration.

[0131] In step S03, when the current wheel edge torque is less than the current torque threshold, it is determined that the target vehicle has an engine starting demand.

[0132] It can be understood that the current wheel edge torque is compared with the motor starting torque threshold, and when the current wheel edge torque is less than the motor starting torque threshold, it indicates that the hybrid vehicle cannot drive the vehicle to normally travel at the current slope in the pure electric mode, that is, the current vehicle is insufficient in power, and therefore, it is determined that the hybrid vehicle has a demand for starting the engine to improve the driving performance of the vehicle.

[0133] It should be noted that, as shown in Figure 6 and Figure 7 , the vehicle is in a power activation state (new energy ready, or running); the vehicle speed is enabled after being greater than a threshold, and is not enabled when being less than a certain speed; in the case of insufficient driving ability, the vehicle is allowed to stop in the high-altitude working condition; then, the maximum P3 driving ability M1 is converted according to the available power of the battery, and the specific conversion method is T=9550×P / N, wherein T refers to torque, 9550 refers to a unit conversion constant, which is applicable to the power unit of kilowatt, P refers to the maximum power, and N refers to the current motor speed; when the temperature is too high, the torque capability limit of the motor controller is calculated to obtain the maximum allowable value M2 of the motor driving ability; based on M1 and M2, the wheel edge available torque calculated by the system in the EV driving mode is obtained; when the P3 motor (P3: the motor located behind the gearbox) is insufficient in ability, the ECVT power split gear is cut in from the pure electric EV gear in advance, and the engine is started to realize the engine auxiliary wheel edge driving.

[0134] The embodiment obtains the current motor speed, the current vehicle slope and the current wheel edge torque when the target vehicle is in the power activation state and the current vehicle speed is greater than the vehicle speed threshold; determines the corresponding current torque threshold according to the current motor speed and the current vehicle slope; and determines that the target vehicle has the engine starting demand when the current wheel edge torque is less than the current torque threshold. By determining whether the target vehicle has the engine starting demand according to the current wheel edge torque and the current torque threshold when the vehicle is in the power activation state and the current vehicle speed is greater than the vehicle speed threshold, whether the engine has the starting demand is accurately identified, and the driving performance of the vehicle is improved.

[0135] Exemplarily, in order to facilitate understanding of the implementation process of the engine control method obtained after the above embodiment one, please refer to Figure 8 , Figure 8 A brief flowchart of an engine control method is provided, specifically: a start-stop control method based on a slope and a driving motor is designed, the engine is started in advance in a driving motor capability limited scene; the switching of a pure electric EV gear-ECVT power split is implemented, the engine starting is requested in advance by identifying the motor torque limitation and the large slope scene, and the mode switching and gear execution of the ECVT power split gear are implemented by controlling the gear ring speed to be hung into the S1 synchronizer.

[0136] It should be noted that the above examples are only used for understanding the present application and do not constitute a limitation on the engine control method of the present application, and more forms of simple transformation based on this technical concept are within the protection scope of the present application.

[0137] The present application also provides an engine control device, please refer to Figure 9 , the engine control device comprises:

[0138] The processing module 10 is configured to obtain a target speed difference and a target torque change rate when the target vehicle has an engine starting demand.

[0139] The processing module 10 is further configured to determine a target synchronization state according to the target speed difference and the target torque change rate.

[0140] The processing module 10 is further configured to perform gear switching according to a target gear instruction and a speed and torque adjusting instruction when the target synchronization state is a synchronization success state, and obtain a gear switching state.

[0141] The starting module 20 is configured to start the engine of the target vehicle when the gear switching state is a gear switching completion state.

[0142] Optionally, the processing module 10 is further configured to:

[0143] obtaining a current motor speed, a current vehicle slope and a current wheel side torque when the target vehicle is in a power activated state and a current vehicle speed is greater than a vehicle speed threshold;

[0144] determining a corresponding current torque threshold according to the current motor speed and the current vehicle slope;

[0145] determining that the target vehicle has an engine starting demand when the current wheel side torque is less than the current torque threshold.

[0146] Optionally, the processing module 10 is further configured to:

[0147] obtaining a current battery torque according to a current battery power and a preset conversion strategy when the target vehicle is in an electric mode, and obtaining a motor limit torque;

[0148] performing torque calculation according to the current battery torque and the motor limit torque to obtain a current wheel side torque.

[0149] Optionally, the processing module 10 is further configured to:

[0150] comparing the target speed difference and a speed difference threshold to obtain a speed difference comparison result;

[0151] comparing the target torque change rate and a torque change rate threshold to obtain a torque change rate comparison result;

[0152] determining that a target synchronization state is a synchronization success state when the speed difference comparison result is that the target speed difference is less than the speed difference threshold and the torque change rate comparison result is that the target torque change rate is less than the torque change rate threshold;

[0153] determining that the target synchronization state is a synchronization failure state when at least one of the speed difference comparison result is that the target speed difference is greater than or equal to the speed difference threshold and the torque change rate comparison result is that the target torque change rate is greater than or equal to the torque change rate threshold.

[0154] Optionally, the processing module 10 is further configured to:

[0155] determining a gear speed difference according to a target gear speed corresponding to the target gear instruction and a current gear speed;

[0156] performing PID calculation according to the gear speed difference and the speed and torque instruction to obtain a speed demand torque;

[0157] performing gear shifting without a clutch according to the speed demand torque to determine a gear shifting state.

[0158] Optionally, the processing module 10 is further configured to:

[0159] switching the gear according to the speed regulation demand torque, to obtain a gear switching position;

[0160] determining a target position difference according to the gear switching position and the target gear position;

[0161] determining a gear switching state according to the target position difference and a position difference threshold.

[0162] Optionally, the processing module 10 is further configured to:

[0163] comparing the target position difference and the position difference threshold, to obtain a position difference comparison result;

[0164] when the position difference comparison result is that the target position difference is less than the position difference threshold, determining that the gear switching state is a gear switching completion state.

[0165] The engine control device provided in the present application adopts the engine control method in the above embodiments, and can solve the technical problem that in the working condition of a low-torque motor and insufficient battery discharge power, power is weak or acceleration overtaking is slow during highland slope acceleration overtaking. Compared with the prior art, the engine control device provided in the present application has the same beneficial effects as the engine control method provided in the above embodiments, and other technical features in the engine control device are the same as the features disclosed in the above embodiments, which will not be repeated here.

[0166] The present application provides an engine control device, which comprises at least one processor and a memory in communication connection with the at least one processor, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the engine control method in the above embodiment one.

[0167] Reference will now be made to the following description Figure 10 which shows a structural schematic diagram of an engine control device suitable for implementing the embodiments of the present application. The engine control device in the embodiments of the present application can include but is not limited to mobile terminals such as mobile phones, notebook computers, digital broadcast receivers, PDAs (Personal Digital Assistant), PADs (Portable Application Description), PMPs (Portable Media Player), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), and the like, and fixed terminals such as digital TVs, desktop computers, and the like. Figure 10 The engine control device shown is only an example, and should not impose any limitation on the functions and use range of the embodiments of the present application.

[0168] As shown in Figure 10 The engine control device can include a processing device 1001 (e.g., a central processing unit, a graphics processing unit, etc.) that can perform various appropriate actions and processes in accordance with a program stored in a read only memory (ROM) 1002 or a program loaded from a storage device 1003 into a random access memory (RAM) 1004. Various programs and data required for operation of the engine control device are also stored in the RAM 1004. The processing device 1001, the ROM 1002, and the RAM 1004 are connected to each other by a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Generally, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; the storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the engine control device to communicate wirelessly or by wire with other devices to exchange data. Although the engine control device having various systems is shown in the figure, it should be understood that all of the systems shown are not required to be implemented or possessed. More or less systems can be alternatively implemented or possessed.

[0169] In particular, the processes described above with reference to the flowcharts can be implemented as a computer software program according to embodiments of the present disclosure. For example, embodiments of the present disclosure include a computer program product comprising a computer program carried on a computer readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network by a communication device, or installed from the storage device 1003, or installed from the ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the methods of embodiments of the present disclosure are performed.

[0170] The engine control device provided by the present disclosure adopts the engine control method in the above-mentioned embodiments, and can solve the technical problems of weak power or slow acceleration in the case of insufficient discharge power of the battery under the working condition of a low-torque motor. Compared with the prior art, the engine control device provided by the present disclosure has the same beneficial effects as the engine control method provided by the above-mentioned embodiments, and other technical features in the engine control device are the same as the features disclosed in the previous embodiment method, which will not be repeated here.

[0171] It should be understood that various aspects disclosed herein can be implemented in hardware, software, firmware, or combinations thereof, to achieve the various aspects disclosed herein. In the description above, specific terminology is used to describe particular features, structures, materials or characteristics. It should be understood, however, that the terminology is used only in a descriptive sense and not for purposes of limitation.

[0172] The above description is only specific embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

[0173] The present application provides a computer-readable storage medium having stored thereon computer-readable program instructions (i.e., a computer program) for executing the engine control method in the above-described embodiments.

[0174] The computer-readable storage medium provided by the present application may, for example, be a U disk, but is not limited to an electric, magnetic, optical, electromagnetic, infrared, or semiconductor system, system, or device, or any combination thereof. More specific examples of the computer-readable storage medium can include, but are not limited to, an electric connection having one or more conductive wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present embodiment, the computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, system, or device. The program code contained on the computer-readable storage medium can be transmitted by any suitable medium, including but not limited to an electric wire, an optical cable, an RF (Radio Frequency), etc., or any suitable combination thereof.

[0175] The above-described computer-readable storage medium can be included in the engine control device; or can exist separately without being assembled into the engine control device.

[0176] The computer readable storage medium described above carries one or more programs, when the one or more programs are executed by the engine control device, cause the engine control device to: obtain a target speed difference and a target torque change rate when the target vehicle has an engine start demand; determine a target synchronization state according to the target speed difference and the target torque change rate; perform gear shifting according to a target gear instruction and a speed-torque adjusting instruction to obtain a gear shifting state when the target synchronization state is a synchronization success state; and start an engine of the target vehicle when the gear shifting state is a gear shifting completion state.

[0177] Computer program code for carrying out operations of the present application can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0178] The flow diagrams and the block diagrams in the drawings are illustrations of architectures, functionalities, and operations of possible implementations of systems, methods, and computer program products according to various embodiments of the present application. In this regard, each block in the flow diagrams or block diagrams can represent a module, a segment, or a portion of code, which comprises one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions noted in the blocks can occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and / or flow diagrams, and combinations thereof, can be implemented by special purpose hardware-based systems that perform the specified functions or operations, or combinations of special purpose hardware and computer instructions.

[0179] The modules described in the embodiments of the present application can be implemented in the form of software or in the form of hardware. In some cases, the name of the module does not constitute a limitation on the module itself.

[0180] The readable storage medium provided by the present application is a computer readable storage medium, which stores computer readable program instructions (i.e., a computer program) for executing the engine control method described above, and can solve the technical problems of weak power or slow acceleration in the case of insufficient discharge power of the battery under the working condition of the low-torque motor and the battery. Compared with the prior art, the computer readable storage medium provided by the present application has the same beneficial effects as the engine control method provided by the above-mentioned embodiments, and will not be described here.

[0181] The present application also provides a computer program product comprising a computer program, which, when executed by a processor, implements the steps of the engine control method as described above.

[0182] The computer program product provided by the present application can solve the technical problems of weak power or slow acceleration in the case of insufficient discharge power of the battery under the working condition of the low-torque motor and the battery. Compared with the prior art, the computer program product provided by the present application has the same beneficial effects as the engine control method provided by the above-mentioned embodiments, and will not be described here.

[0183] The above only describes some embodiments of the present application, and does not limit the patent scope of the present application. Any equivalent structural transformation, direct / indirect application in other related technical fields based on the technical concept of the present application, and the contents of the present application and the accompanying drawings are included in the patent protection scope of the present application.

Claims

1. An engine control method characterized by, The engine control method comprises: When the target vehicle has an engine starting demand, a target speed difference and a target torque change rate are obtained; A target synchronization state is determined according to the target speed difference and the target torque change rate; When the target synchronization state is a synchronization success state, gear shifting is performed according to a target gear instruction and a speed and torque adjusting instruction, and a gear shifting state is obtained; When the gear shifting state is a gear shifting completion state, the engine of the target vehicle is started; The gear shifting performed according to the target gear instruction and the speed and torque adjusting instruction to obtain the gear shifting state comprises: A gear speed difference is determined according to a target gear speed corresponding to the target gear instruction and a current gear speed; A speed demand torque is obtained by PID calculation according to the gear speed difference and the speed and torque adjusting instruction; Gear shifting without a clutch is performed according to the speed demand torque to determine the gear shifting state; The gear shifting performed according to the speed demand torque to determine the gear shifting state comprises: Gear shifting is performed according to the speed demand torque to obtain a gear shifting position; A target position difference is determined according to the gear shifting position and a target gear position; The gear shifting state is determined according to the target position difference and a position difference threshold.

2. The method of claim 1, wherein, Before the target speed difference and the target torque change rate are obtained when the target vehicle has the engine starting demand, the method further comprises: When the target vehicle is in a power activation state and a current vehicle speed is greater than a vehicle speed threshold, a current motor speed, a current vehicle slope and a current wheel edge torque are obtained; A current torque threshold corresponding to the current motor speed and the current vehicle slope is determined; When the current wheel edge torque is less than the current torque threshold, it is determined that the target vehicle has the engine starting demand.

3. The method of claim 2, wherein, The step of obtaining the current wheel edge torque comprises: When the target vehicle is in an electric mode, a current battery torque is determined according to a current battery power and a preset conversion strategy, and a motor limit torque is obtained; The current wheel edge torque is obtained by torque calculation according to the current battery torque and the motor limit torque.

4. The method of claim 1, wherein, The target synchronization state is determined according to the target speed difference and the target torque change rate, which comprises: A speed difference comparison result is obtained by comparing the target speed difference with a speed difference threshold; A torque change rate comparison result is obtained by comparing the target torque change rate with a torque change rate threshold; When the speed difference comparison result is that the target speed difference is less than the speed difference threshold and the torque change rate comparison result is that the target torque change rate is less than the torque change rate threshold, it is determined that the target synchronization state is a synchronization success state; When at least one of the speed difference comparison result is that the target speed difference is greater than or equal to the speed difference threshold and the torque change rate comparison result is that the target torque change rate is greater than or equal to the torque change rate threshold, it is determined that the target synchronization state is a synchronization failure state.

5. The method of claim 1, wherein, The gear shifting state is determined according to the target position difference and the position difference threshold, which comprises: A position difference comparison result is obtained by comparing the target position difference with the position difference threshold; When the position difference comparison result is that the target position difference is less than the position difference threshold, it is determined that the gear shifting state is a gear shifting completion state.

6. An engine control device characterized by comprising: The device comprises: The processing module is configured to obtain a target speed difference and a target torque change rate when the target vehicle has an engine starting demand; The processing module is further configured to determine a target synchronization state according to the target speed difference and the target torque change rate; The processing module is further configured to perform gear shifting according to a target gear instruction and a speed and torque adjusting instruction when the target synchronization state is a synchronization success state, to obtain a gear shifting state; The processing module is further configured to determine a gear speed difference according to a target gear speed corresponding to the target gear instruction and a current gear speed; perform PID calculation according to the gear speed difference and the speed and torque adjusting instruction, to obtain a speed demand torque; perform gear shifting without a clutch according to the speed demand torque, to determine a gear shifting state; The processing module is further configured to perform gear shifting according to the speed demand torque, to obtain a gear shifting position; determine a target position difference according to the gear shifting position and a target gear position; determine a gear shifting state according to the target position difference and a position difference threshold; The starting module is configured to start the engine of the target vehicle when the gear shifting state is a gear shifting completion state.

7. An engine control apparatus characterized by comprising: The device comprises a memory, a processor, and a computer program stored on the memory and executable on the processor, and the computer program is configured to implement the steps of the engine control method according to any one of claims 1 to 5.

8. A storage medium, characterized by The storage medium is a computer readable storage medium, and the storage medium stores a computer program, and the computer program is executed by the processor to implement the steps of the engine control method according to any one of claims 1 to 5.

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