Engine control method, device and equipment and storage medium

Abstract

The invention discloses an engine control method, device and equipment and a storage medium, and relates to the technical field of vehicle control, and the engine control method comprises the steps that when a target vehicle has an engine starting requirement, a target rotating speed difference and a target torque change rate are obtained; determining a target synchronization state according to the target rotating speed difference and the target torque change rate; when the target synchronization state is a synchronization success state, gear switching is carried out according to a target gear instruction and a speed regulation and torque regulation instruction, and a gear switching state is obtained; and when the gear switching state is a gear switching completion state, an engine of the target vehicle is started. In the running process of the EV (electric vehicle), the engine needs to be started in advance for transition in the scene that large ramps possibly exist and power is insufficient, the pure electric mode EV gear is transited to the ECVT gear, the engine is started, driving is conducted through a driving motor and the ECVT at the same time, and the driving performance of the whole vehicle is improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to engine control methods, devices, equipment and storage media. Background Art

[0002] For hybrid vehicles, engine start control generally starts the engine for charging or direct drive based on the power demand of the driver, SOC power conservation demand, etc.; the shifting process of hybrid vehicles in the existing technology mostly adopts power interruption shifting (series-parallel), especially when the power battery is low and the discharge power is limited, or the motor drive torque is limited, the power interruption shifting is particularly obvious, and for vehicles equipped with low-torque motors and under conditions where the battery discharge power is insufficient, accelerating and overtaking on plateau slopes is prone to problems such as weak power or slow acceleration and overtaking. Summary of the invention

[0003] The main purpose of this application is to provide an engine control method, device, equipment and storage medium, aiming to solve the technical problems of weak power or slow acceleration and overtaking on plateau slopes when the engine is equipped with a low-torque motor and the battery discharge power is insufficient.

[0004] To achieve the above objectives, the present application proposes an engine control method, the engine control method comprising: When the target vehicle has an engine start demand, obtaining a target speed difference and a target torque change rate; determining a target synchronization state according to the target speed difference and the target torque change rate; When the target synchronization state is a synchronization success state, the gear switching is performed according to the target gear command and the speed and torque adjustment command to obtain the gear switching state; When the gear switching state is a gear switching completion state, the engine of the target vehicle is started.

[0005] In one embodiment, when the target vehicle has an engine start requirement, before obtaining the target speed difference and the target torque change rate, the method further includes: When the target vehicle is in a power activation state and the current vehicle speed is greater than the vehicle speed threshold, the current motor speed, the current vehicle slope and the current wheel torque are obtained; Determine a corresponding current torque threshold according to the current motor speed and the current vehicle slope; When the current wheel-side torque is less than the current torque threshold, it is determined that the target vehicle has an engine start demand.

[0006] In one embodiment, the step of obtaining the current wheel torque includes: When the target vehicle is in pure electric mode, determining the current battery torque according to the current battery power and a preset conversion strategy, and obtaining the motor limit torque; The torque is calculated according to the current battery torque and the motor limit torque to obtain the current wheel torque.

[0007] In one embodiment, determining the target synchronization state according to the target speed difference and the target torque change rate includes: Comparing the target speed difference with the speed difference threshold to obtain a speed difference comparison result; Comparing the target torque change rate with a torque change rate threshold to obtain a torque change rate comparison result; 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; 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, the target synchronization state is determined to be a synchronization failure state.

[0008] In one embodiment, the step of performing gear switching according to the target gear command and the speed and torque adjustment command to obtain the gear switching state includes: Determining 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 adjustment command to obtain the speed regulation required torque; The gear switching is performed without a clutch according to the speed regulation requirement torque, and the gear switching state is determined.

[0009] In one embodiment, performing clutchless gear switching according to the speed regulation required torque and determining the gear switching state includes: Performing gear switching according to the speed regulation required torque to obtain a gear switching position; determining a target position difference according to the gear shift position and the target gear position; The gear switching state is determined according to the target position difference and the position difference threshold.

[0010] In one embodiment, determining the gear shift state according to the target position difference and the position difference threshold comprises: Comparing the target position difference with the position difference threshold to obtain a position difference comparison result; When the position difference comparison result is that the target position difference is smaller than the position difference threshold, it is determined that the gear switching state is a gear switching completion state.

[0011] In addition, to achieve the above-mentioned purpose, the present application also proposes an engine control device, the engine control device comprising: A processing module, used for determining a target speed difference according to a ring gear speed and a synchronizer speed when there is a demand for starting the engine of the target vehicle; The processing module is further used to determine a target synchronization state according to the target rotation speed difference and the rotation speed difference threshold; The processing module is further used to perform gear switching according to the target gear instruction and the speed and torque adjustment instruction to obtain the gear switching state when the target synchronization state is a synchronization success state; A starting module is used to start the target vehicle engine when the gear switching state is a gear switching completion state.

[0012] In addition, to achieve the above-mentioned purpose, the present application also proposes an engine control device, which includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the engine control method as described above.

[0013] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the engine control method described above are implemented.

[0014] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, the steps of the engine control method described above are implemented.

[0015] This application determines the target speed difference according to the ring gear speed and the synchronizer speed when the target vehicle has an engine start demand; determines the target synchronization state according to the target speed difference and the speed difference threshold; when the target synchronization state is a synchronization success state, performs gear switching according to the target gear command and the speed adjustment command to obtain the gear switching state; when the gear switching state is a gear switching completion state, starts the engine of the target vehicle. During EV (electric vehicle) driving, the engine transition is required in advance for scenarios where there may be large slopes and insufficient power, the pure electric mode EV gear is transitioned to the ECVT (electronically controlled continuously variable transmission) gear, the engine is started, and the drive motor and ECVT are driven simultaneously, thereby improving the driving performance of the entire vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0018] Figure 1 A schematic diagram of a flow chart provided for the first embodiment of the engine control method of the present application; Figure 2 A schematic diagram of a speed regulation request torque calculation process provided in Embodiment 1 of the engine control method of the present application; Figure 3 A schematic diagram of a gear shifting process provided in Embodiment 1 of the engine control method of the present application; Figure 4 A flow chart of the second embodiment of the engine control method of the present application; Figure 5 A schematic diagram of the correspondence between the motor speed and the motor starting torque threshold under different slopes provided in the second embodiment of the engine control method of the present application; Figure 6 A schematic diagram of an engine start demand determination process provided in Embodiment 2 of the engine control method of the present application; Figure 7 A schematic diagram of an overall control method provided for the second embodiment of the engine control method of the present application; Figure 8 A schematic diagram of a simplified flow chart of an engine control method provided in Embodiment 2 of the present application; Fig. 9 This is a schematic diagram of the module structure of the engine control device according to an embodiment of the present application; Fig.10 Schematic diagram of the device structure of the hardware operating environment involved in the engine control method in the embodiment of the present application.

[0019] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0020] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0021] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0022] The main solution of the embodiment of the present application is: when there is a demand for engine start of the target vehicle, the target speed difference and the target torque change rate are obtained; the 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, the gear is switched according to the target gear command and the speed and torque adjustment command to obtain the gear switching state; when the gear switching state is a gear switching completion state, the engine of the target vehicle is started.

[0023] For hybrid vehicles, engine start control generally starts the engine for charging or direct drive based on the power demand of the driver, SOC power conservation demand, etc.; the shifting process of hybrid vehicles in the existing technology mostly adopts power interruption shifting (series-parallel), especially when the power battery is low and the discharge power is limited, or the motor drive torque is limited, the power interruption shifting is particularly obvious, and for vehicles equipped with low-torque motors and under conditions where the battery discharge power is insufficient, accelerating and overtaking on plateau slopes is prone to problems such as weak power or slow acceleration and overtaking.

[0024] This application determines the target speed difference according to the ring gear speed and the synchronizer speed when the target vehicle has an engine start demand; determines the target synchronization state according to the target speed difference and the speed difference threshold; when the target synchronization state is a synchronization success state, performs gear switching according to the target gear command and the speed adjustment command to obtain the gear switching state; when the gear switching state is a gear switching completion state, starts the engine of the target vehicle. During EV (electric vehicle) driving, the engine transition is required in advance for scenarios where there may be large slopes and insufficient power, the pure electric mode EV gear is transitioned to the ECVT (electronically controlled continuously variable transmission) gear, the engine is started, and the drive motor and ECVT are driven simultaneously, thereby improving the driving performance of the entire vehicle.

[0025] It should be noted that the execution subject of this embodiment may be a computing service device with data processing, network communication and program running functions, such as a tablet computer, a personal computer, a mobile phone, etc., or an engine control device capable of realizing the above functions, etc. The following takes the engine control device as the execution subject as an example to illustrate this embodiment and the following embodiments.

[0026] Based on this, the embodiment of the present application provides an engine control method, referring to Figure 1 , Figure 1 This is a flow chart of the first embodiment of the engine control method of the present application.

[0027] In this embodiment, the engine control method includes steps S10 to S40: Step S10, when the target vehicle has an engine start requirement, obtaining a target speed difference and a target torque change rate; It should be noted that the power system of a hybrid vehicle generally consists of a drive motor, a generator and an engine. The three power sources can output torque at the wheel end to drive the vehicle according to the working conditions. Figure 2 As shown, the combination of the power source of this embodiment is a clutchless shifting system, which controls the speed difference between the input shaft and the output shaft of the synchronizer and synchronizes the torque of the input end of the synchronizer with the acceleration of the torque of the output end. When the speed difference between the two ends of the synchronizer is less than a certain value and synchronizes with the acceleration of the output torque of the two ends of the synchronizer, the speed of the shift hub can be controlled to achieve gear shifting; the timing of the gear position is controlled by the VCU (vehicle controller) and implemented by the HTCU (hybrid transmission control unit) controller.

[0028] It should be noted that in order to meet the requirement that hybrid vehicles can operate in different modes, the hybrid transmission of the hybrid vehicle can provide a variety of gears accordingly, and different gears can match different power source combinations.

[0029] Exemplarily, the hybrid transmission of the embodiment of the present application includes multiple gears, for example, multiple gears are defined as station 1 to station 10, wherein station 1 is a series gear, station 2, station 4, station 8 and station 10 are parallel direct drive gears, and station 3, station 5, station 7 and station 9 are ECVT gears. In station 1, the engine continues to work in the high efficiency zone after starting, and the engine does not directly participate in the drive, but supplies power to the power battery through the generator, and the drive motor is used as the power source of the whole vehicle to drive the whole vehicle to run. Stations 2, 4, 8 and 10 correspond to the 1st, 2nd, 3rd and 4th direct drive gears, respectively. From station 2 to station 10, the speed ratio between the ring gear of the planetary gear set, the engine and the generator gradually decreases. At station 2 and station 8, the engine participates in direct drive, and the speed ratio between the ring gear, the engine and the generator is 1:1:1. The planets are arranged as a whole, and can rely on the generator and the drive motor to generate electricity. At station 4 and station 10, the engine participates in direct drive, the GCU (motor controller) locks the torque, and the speed is controlled at 0RPM and 0nm, and can rely on the drive motor to generate electricity. At stations 3, 5, 7 and 9, after the engine is started, it is necessary to maintain the ring gear torque balance, and the generator speed, engine speed and ring gear speed need to maintain a fixed speed ratio relationship. The torque closed-loop control can maintain the lever torque balance and realize the smooth speed transition of the gear. Therefore, in this embodiment, when entering ECVT2_1 (station 7) from EV (station 6), the S1 synchronizer needs to be engaged.

[0030] It can be understood that the target vehicle refers to a hybrid vehicle, the engine start demand is used to indicate the demand to start the engine when the vehicle's driving ability 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 operating 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 over time, which is usually used to describe the increase or decrease of torque over time.

[0031] In a specific implementation, when there is a need to start the engine of a hybrid vehicle, it indicates that the current hybrid vehicle is underpowered, and then the difference is calculated based on the ring gear speed in the planetary carrier and the current operating speed of the synchronizer to obtain the target speed difference, and then the rate of change of torque over time is calculated based on the speed change rate and the moment of inertia to obtain the target torque change rate, and then based on the calculated difference between the synchronizer speed and the ring gear speed and the rate of change of torque over time, it is determined whether the synchronization conditions are met, that is, whether it is possible to switch from the EV (station 6) gear to the ECVT gear (station 7).

[0032] Step S20, determining a target synchronization state according to the target speed difference and the target torque change rate; It can be understood that the target synchronization state includes a synchronization success state and a synchronization failure state.

[0033] In specific implementation, the synchronization conditions in this embodiment are that the speed difference is less than a threshold and the torque change rate is less than a threshold. When the synchronization conditions are met, the gear shift is performed: when the torque change rate is higher than a certain threshold, it is considered that the synchronization has failed, and the gear shift is performed; or when the speed difference at both ends of the synchronizer is greater than a certain threshold, it is considered that the synchronization has failed, and the gear shift is also performed; the torque change rate calculation method: GCU (Generator Control Unit for Range Extender Vehicles) angular velocity × moment of inertia = torque, angular velocity = speed × 2π / 60, synchronizer speed difference: target speed - actual speed < certain threshold.

[0034] It should be noted that the monitoring principle of the torque change rate is the same as that of the speed change rate: for the synchronous speed difference condition: if it is less than the threshold value A, it is considered that the synchronization condition 1 is met, and if it is greater than the threshold value B, it is considered that the synchronization condition is not met. Threshold B = (A + Aoffset), Aoffset is generally a positive value, and it is already in the synchronous state. During the process of the synchronous speed difference from A to B, the synchronization condition is considered to be met; the current project boundary is determined by the synchronization capability of the synchronizer, A = 80rpm, B = 150rpm; for the synchronous speed change rate condition, the same logic applies: if it is less than the threshold value ωC, it is considered that the synchronization condition 1 is met, and if it is greater than the threshold value ωD, it is considered that the synchronization condition is not met. Threshold ωD = (ωC + ωCoffset), ωCoffset is generally a positive value, and it is already in the synchronous state. During the process of the synchronous speed difference from A to B, the synchronization condition is considered to be met; when the speed change rate and the synchronous speed difference are met at the same time, the synchronization condition is considered to be met; C = 300rpm / s 2 , D = 550 rpm / s 2 , J = 0.17, Torque ̇=J×ω.

[0035] In a feasible implementation, step S20 may include steps A21 to A24: Step A21, comparing the target speed difference with the speed difference threshold to obtain a speed difference comparison result; It can be understood that the speed difference comparison result refers to the comparison result between the target speed difference and the speed difference threshold, and the speed difference threshold is used to determine whether the speed difference critical value meets the synchronization condition.

[0036] In a specific implementation, the target speed difference is compared with a speed difference critical value used to determine whether the synchronization condition is met, and a result is obtained that the target speed difference is less than the speed difference critical value used to determine whether the synchronization condition is met, or the target speed difference is greater than or equal to the speed difference critical value used to determine whether the synchronization condition is met, that is, the speed difference comparison result.

[0037] Step A22, comparing the target torque change rate with the torque change rate threshold to obtain a torque change rate comparison result; It can be understood that the torque change rate comparison result refers to the comparison result between the target torque change rate and the torque change rate threshold, and the torque change rate threshold is used to determine whether the torque change rate critical value of the synchronization condition is met.

[0038] In a specific implementation, the target speed difference is compared with a speed difference critical value used to determine whether the synchronization condition is met, and a result is obtained that the target torque change rate is less than the torque change rate critical value used to determine whether the synchronization condition is met, or the target torque change rate is greater than or equal to the torque change rate critical value used to determine whether the synchronization condition is met, that is, the torque change rate comparison result.

[0039] Step A23, 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; In a specific implementation, when the speed difference comparison result is that the target speed difference is less than the speed difference critical value used to determine 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, it indicates that the current speed difference and torque change rate both meet the synchronization conditions. Therefore, the target synchronization state is determined to be a successful synchronization state.

[0040] 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 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, determines that the target synchronization state is a synchronization failure state.

[0041] In a specific implementation, when the speed difference comparison result is that the target speed difference is greater than or equal to the speed difference critical value used to determine 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 at least one of the torque change rate thresholds, it indicates that at least one of the current speed difference and the torque change rate does not meet the synchronization condition, and therefore, the target synchronization state is determined to be a synchronization failure state.

[0042] It should be noted that the gear-shifting feature: shifting from direct drive gear to ECVT gear, or shifting from ECVT gear to EV gear, is defined as gear-shifting. The gear-shifting condition from direct drive gear to ECVT gear: the planetary carrier torque needs to maintain a balanced gear to shift the S2 synchronizer, that is, M GEN +M ICE =0N·M, currently it is less than 4.5N·M, and the gear can be disengaged; the condition for shifting from ECVT gear to EV gear: the planetary carrier torque needs to be maintained at 0nm, that is, the engine and generator torques are both less than a threshold value, in order to disengage the S1 synchronizer, and the planetary carrier torque needs to be kept balanced at 0N·M.

[0043] It should be noted that the gear-engaging feature: ECVT gear shift direct drive gear, or EV gear shift ECVT gear, is defined as gear-engaging; ECVT gear shift direct drive gear condition: obtain the torque change rate of the generator and the speed difference between the two ends of the synchronizer; if the torque change rate is less than or equal to the change rate threshold, and the speed difference between the two ends is less than or equal to the speed difference threshold, it is determined that the target gear shift synchronization condition is met. EV gear shift ECVT gear can be applied, because when EV is hung ECVT, the engine is originally controlled according to 0N·M, and the generator only has speed regulation torque.

[0044] Step S30, when the target synchronization state is a synchronization success state, performing a gear switching according to the target gear command and the speed and torque adjustment command to obtain a gear switching state; It can be understood that the target gear instruction is used to indicate which specific gear the transmission should shift to. In this embodiment, the pure electric EV gear is switched to the ECVT power split gear. The speed and torque adjustment instruction refers to the instruction for adjusting the speed and torque during the gear shifting process. The gear switching status includes the gear switching completion status and the gear switching failure status.

[0045] In the specific implementation, when the target synchronization state is the synchronization success state, it indicates that the gear shifting conditions are met and the gear shifting operation can be performed. Then, the gear switching is performed according to the instructions indicating which specific gear the transmission should be switched to, that is, the ECVT power split gear, and the instructions for adjusting the speed and torque during the gear shifting process. Finally, the gear switching state is obtained.

[0046] In a feasible implementation, step S30 may include steps A31 to A33: Step A31, determining a gear speed difference according to a target gear speed corresponding to the target gear instruction and a current gear speed; It can be understood that the target gear speed refers to the speed corresponding to 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 corresponding to the target gear and the speed of the current gear.

[0047] In a specific implementation, a difference calculation is performed based on the speed corresponding to the target gear and the speed of the current gear, and then the difference between the speed corresponding to the target gear and the speed of the current gear is obtained based on the calculation result.

[0048] Step A32, performing PID calculation according to the gear speed difference and the speed and torque adjustment command to obtain the speed adjustment required torque; It can be understood that the speed regulation required torque refers to the torque required to adjust the speed.

[0049] In the specific implementation, the speed difference needs to be kept less than a certain threshold during the gear shifting process. Therefore, by adjusting the speed and torque instructions, a PID calculation is performed based on the difference between the speed corresponding to the target gear and the speed of the current gear, and the torque required to adjust the speed is determined based on the calculation results.

[0050] Step A33, performing clutchless gear switching according to the speed regulation required torque, and determining the gear switching state.

[0051] It can be understood that during the gear shifting process, the speed is controlled by calculating the torque required to adjust the speed, thereby determining whether the gear switching is completed, that is, the gear switching state.

[0052] In a feasible implementation, step A33 may include steps B331 to B333: Step B331, switching gears according to the speed regulation required torque to obtain a gear switching position; It can be understood that the gear switching position refers to the position during the gear switching process.

[0053] In a specific implementation, the speed is controlled by adjusting the torque required for the speed, that is, the gear is switched. During the gear switching process, the current position is monitored in real time to obtain the position during the gear switching process.

[0054] Step B332, determining a target position difference according to the gear switching position and the target gear position; It can be understood that the target position difference refers to the difference between the position of the ECVT power split gear when the gear is switched.

[0055] Step B333, determining the gear switching state according to the target position difference and the position difference threshold.

[0056] It can be understood that the position difference threshold is a critical value of the position difference used to determine whether the gear shift is completed.

[0057] In a specific implementation, the gear switching state is determined based on the comparison result by comparing the difference between the position of the ECVT power split gear during gear switching and a position difference threshold used to determine whether the gear switching is completed.

[0058] In a feasible implementation, step B333 may include steps C3331-C3332: Step C3331, comparing the target position difference with the position difference threshold to obtain a position difference comparison result; It can be understood that the position difference comparison result includes a result that the target position difference is less than a 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 switching is completed.

[0059] In a specific implementation, the difference between the position of the ECVT power split gear during gear switching and the position difference critical value used to determine whether the gear switching is completed is compared to obtain a target position difference less than the position difference threshold result and a target position difference greater than or equal to the position difference threshold result, that is, a position difference comparison result is obtained.

[0060] Step C3332, 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 the gear switching completion state.

[0061] It can be understood that when the position difference comparison result is that the difference between the position of the ECVT power diversion gear at the time of gear switching is less than the position difference critical value used to determine whether the gear switching is completed, it indicates that the current gear is the ECVT power diversion gear, that is, the gear switching is completed, and then the gear switching state is determined to be the gear switching completion state.

[0062] Step S40, when the gear switching state is a gear switching completion state, starting the engine of the target vehicle.

[0063] It can be understood that when the gear switching state is the gear switching completion state, it indicates that the pure electric EV gear has been switched to the ECVT power split gear, thereby starting the engine of the hybrid vehicle to improve the driving performance of the entire vehicle.

[0064] It should be noted that if Figure 2 As shown, the ring gear speed N ring Rely on P2 motor speed regulation, the target speed is synchronizer speed N S1L (Synchronizer and axle connected together); based on N ring -N S1L The speed difference (the difference between the ring gear speed and the synchronizer speed) is used to adjust the ring gear speed through the GCU (range extender generator controller) torque and lever principle; during the speed regulation process, the GCU is maintained to perform speed closed-loop control. After the HTCU (hybrid transmission control unit) feedback shows that the gear shift is completed, the speed control is exited and the lever balance torque control is entered; The engine maintains a fuel-off state and does not spray fuel for ignition; during the speed regulation process, the motor control mode is the speed control mode, and after the speed regulation is completed, it enters the torque control mode and the speed control mode.

[0065] It should be noted that if Figure 3As shown in the figure, VECU, as the central controller, is mainly responsible for issuing the target gear position command, speed and torque adjustment during the gear shifting process, and judging the gear shifting command; VECU sets the GCU torque, and part of the torque M1 is used to adjust the speed difference between the ring gear and the synchronizer. Part of the torque M2 is used to balance the planetary carrier; the calculation method of M1 is: based on the speed difference at both ends of the synchronizer, the P1 motor torque is obtained through PID adjustment. The calculation method of M2 is: Mg=1 / 3.6Me, where Mg is the generator torque and Me is the engine torque; synchronization condition judgment: after the synchronization condition is met, the VECU engine command, MTCU (automatic transmission control unit) executes the gear shifting; in order to maintain the synchronization process, it is necessary to continuously adjust the GCU speed, and limit the upper and lower limits of the speed adjustment torque; during the synchronization process, the synchronous execution of the MTCU feedback shift is completed; finally, the pure electric to ECVT power split gear is switched.

[0066] This embodiment determines the target speed difference according to the ring gear speed and the synchronizer speed when the target vehicle has an engine start demand; determines the target synchronization state according to the target speed difference and the speed difference threshold; when the target synchronization state is a synchronization success state, performs gear switching according to the target gear command and the speed adjustment command to obtain the gear switching state; when the gear switching state is a gear switching completion state, starts the engine of the target vehicle. During EV (electric vehicle) driving, the engine transition is required to start the engine in advance for scenarios where there may be large slopes and insufficient power, the pure electric mode EV gear is transitioned to the ECVT (electronically controlled continuously variable transmission) gear, the engine is started, and the drive motor and ECVT are driven simultaneously, thereby improving the driving performance of the entire vehicle.

[0067] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can be referred to the above introduction, and will not be repeated in the following. Figure 4 Before step S10, the engine control method further includes steps S01 to S03: Step S01, when the target vehicle is in a power activation state and the current vehicle speed is greater than a vehicle speed threshold, obtaining the current motor speed, the current vehicle slope and the current wheel torque; It can be understood that the current vehicle slope refers to the slope size of the vehicle currently, and the current wheel-side torque refers to the current wheel-side torque size of the vehicle.

[0068] In a specific implementation, when the hybrid vehicle is in a power activation state (ready) and the current driving speed is greater than the set speed threshold, it indicates that the conditions for determining whether the vehicle has an engine start requirement are met, and then the current motor speed, the current slope of the vehicle, and the current wheel torque of the vehicle are obtained, and based on the above data, it is determined whether the vehicle has an engine start requirement.

[0069] In a feasible implementation, step S01 may include steps A011 to A012: Step A011, when the target vehicle is in pure electric mode, determine the current battery torque according to the current battery power and a preset conversion strategy, and obtain the motor limit torque; It can be understood that the current battery torque refers to the maximum torque corresponding to the battery available power, the motor limit torque refers to the maximum allowable torque value of the motor driving capacity when the torque capacity limit of the motor controller is accepted, and the preset conversion strategy refers to the pre-set strategy for converting the battery available power into torque size.

[0070] In a specific implementation, when the hybrid vehicle is in pure electric drive mode, the corresponding torque is calculated based on the current battery available power through a preset strategy of converting the battery available power into torque, the maximum torque corresponding to the battery available power is obtained, and then the maximum allowable torque value of the motor driving capacity is obtained.

[0071] Step A012, performing torque calculation based on the current battery torque and the motor limit torque to obtain the current wheel torque.

[0072] It can be understood that the current battery torque and the motor limit torque are compared, the smaller torque is selected for wheel torque calculation, and then the current wheel torque is determined according to the transmission system reduction ratio. For example, the current battery torque is less than the motor limit torque. Therefore, when the torque capacity limit of the motor controller is accepted, the wheel torque is calculated based on the maximum allowable torque value of the motor driving capacity and the transmission system reduction ratio to obtain the current wheel torque.

[0073] Step S02, determining a corresponding current torque threshold according to the current motor speed and the current vehicle slope; It can be understood that the current torque threshold refers to the motor starting torque threshold, and the current torque threshold is used to determine whether the pure electric mode can drive the vehicle to travel normally at the current slope.

[0074] In the specific implementation, Figure 5 As shown, according to the current vehicle slope and the current engine speed, the current torque threshold is obtained through the correspondence between the slope, speed and the motor starting torque threshold, wherein the correspondence between the slope, speed and the motor starting torque threshold can be obtained through vehicle calibration.

[0075] Step S03, when the current wheel torque is less than the current torque threshold, it is determined that the target vehicle has an engine start demand.

[0076] It can be understood that when the current wheel-side torque is compared with the motor starting torque threshold, if the current wheel-side torque is less than the motor starting torque threshold, it indicates that the hybrid vehicle cannot drive the vehicle normally at the current slope in pure electric mode, that is, the current vehicle power is insufficient. Therefore, it is determined that the hybrid vehicle needs to start the engine to improve the driving performance of the entire vehicle.

[0077] It should be noted that if Figure 6 and Figure 7 As shown, the vehicle is in a power activation state (new energy ready, or running); the vehicle is enabled after the speed is greater than a threshold, and is not enabled after it is less than a certain speed. Under the high-altitude working condition, parking is allowed when the driving capacity is insufficient; then according to the available power of the battery, the maximum P3 driving capacity M1 is converted, and the specific conversion method is T=9550×P / N, where T refers to torque, 9550 refers to the constant for unit conversion, applicable to power units of kilowatts, P refers to maximum power, and N refers to the current motor speed; when overtemperature, the torque capacity limit of the motor controller is calculated to obtain the maximum allowable value of the motor driving capacity M2, and the available wheel torque calculated by the system during EV driving is obtained based on M1 and M2; when the P3 motor (P3: the motor located behind the gearbox) is insufficient, the pure electric EV gear is switched to the ECVT power diversion gear in advance, and the engine is started to achieve engine-assisted wheel driving.

[0078] This embodiment obtains the current motor speed, the current vehicle slope and the current wheel torque when the target vehicle is in a 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 an engine start demand when the current wheel torque is less than the current torque threshold. By determining whether the target vehicle has an engine start demand according to the current wheel torque and the current torque threshold when the vehicle is in a power activation state and the current vehicle speed is greater than the vehicle speed threshold, it accurately identifies whether the engine has an engine start demand, thereby improving the driving performance of the entire vehicle.

[0079] For example, in order to help understand the implementation process of the engine control method obtained by combining this embodiment with the above-mentioned embodiment 1, please refer to Figure 8 , Figure 8 A brief flow chart of an engine control method is provided, specifically: a start-stop control method based on a ramp and a drive motor is designed, and the engine is started in advance for a scenario in which the drive motor capacity is limited; switching between a pure electric EV gear and ECVT power split is realized, the motor torque limitation and a large ramp scenario are identified, the engine start is requested in advance, and the gear ring speed is controlled by speed and torque regulation to engage the S1 synchronizer to realize mode switching and gear execution of the ECVT power split gear.

[0080] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the engine control method of the present application. More simple transformations based on this technical concept are all within the scope of protection of the present application.

[0081] This application also provides an engine control device, please refer to Fig. 9 , the engine control device comprises: The processing module 10 is used to obtain a target speed difference and a target torque change rate when the target vehicle has an engine start demand; The processing module 10 is further used to determine a target synchronization state according to the target speed difference and the target torque change rate; The processing module 10 is further configured to perform gear switching according to the target gear command and the speed and torque adjustment command to obtain a gear switching state when the target synchronization state is a synchronization success state; The starting module 20 is used to start the target vehicle engine when the gear switching state is the gear switching completion state.

[0082] Optionally, the processing module 10 is further used for: When the target vehicle is in a power activation state and the current vehicle speed is greater than the vehicle speed threshold, the current motor speed, the current vehicle slope and the current wheel torque are obtained; Determine a corresponding current torque threshold according to the current motor speed and the current vehicle slope; When the current wheel-side torque is less than the current torque threshold, it is determined that the target vehicle has an engine start demand.

[0083] Optionally, the processing module 10 is further used for: When the target vehicle is in pure electric mode, determining the current battery torque according to the current battery power and a preset conversion strategy, and obtaining the motor limit torque; The torque is calculated according to the current battery torque and the motor limit torque to obtain the current wheel torque.

[0084] Optionally, the processing module 10 is further used for: Comparing the target speed difference with the speed difference threshold to obtain a speed difference comparison result; Comparing the target torque change rate with a torque change rate threshold to obtain a torque change rate comparison result; 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; 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, the target synchronization state is determined to be a synchronization failure state.

[0085] Optionally, the processing module 10 is further used for: Determining 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 adjustment command to obtain the speed regulation required torque; The gear switching is performed without a clutch according to the speed regulation requirement torque, and the gear switching state is determined.

[0086] Optionally, the processing module 10 is further used for: Performing gear switching according to the speed regulation required torque to obtain a gear switching position; determining a target position difference according to the gear shift position and the target gear position; The gear switching state is determined according to the target position difference and the position difference threshold.

[0087] Optionally, the processing module 10 is further used for: Comparing the target position difference with the position difference threshold to obtain a position difference comparison result; When the position difference comparison result is that the target position difference is smaller than the position difference threshold, it is determined that the gear switching state is a gear switching completion state.

[0088] The engine control device provided by the present application adopts the engine control method in the above embodiment, which can solve the technical problems such as weak power or slow acceleration and overtaking when accelerating and overtaking on a plateau slope under the condition of low-torque motor and insufficient battery discharge power. Compared with the prior art, the beneficial effects of the engine control device provided by the present application are the same as the beneficial effects of the engine control method provided by the above embodiment, and the other technical features in the engine control device are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0089] The present application provides an engine control device, which includes: at least one processor; and a memory that is communicatively connected to the at least one processor; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the engine control method in the above-mentioned embodiment one.

[0090] Reference below Fig.10, which shows a schematic diagram of the structure of an engine control device suitable for implementing the embodiment of the present application. The engine control device in the embodiment of the present application may include but is not limited to mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Fig.10 The engine control device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0091] like Fig.10 As shown, the engine control device may include a processing device 1001 (e.g., a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the engine control device are also stored. The processing device 1001, ROM1002, and RAM1004 are connected to each other through 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: Liquid Crystal Display), a speaker, a vibrator, etc.; a 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 with other devices wirelessly or by wire to exchange data. Although the figure shows an engine control device with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems can be implemented or have alternatively.

[0092] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0093] The engine control device provided by the present application adopts the engine control method in the above embodiment, which can solve the technical problems such as weak power or slow acceleration and overtaking when accelerating and overtaking on plateau slopes under the condition of low-torque motor and insufficient battery discharge power. Compared with the prior art, the beneficial effects of the engine control device provided by the present application are the same as the beneficial effects of the engine control method provided by the above embodiment, and the other technical features in the engine control device are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0094] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0095] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0096] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, and the computer-readable program instructions are used to execute the engine control method in the above-mentioned embodiment.

[0097] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM: Random Access Memory), a read-only memory (ROM: Read Only Memory), an erasable programmable read-only memory (EPROM: Erasable Programmable Read Only Memory or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM: CD-Read Only Memory), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency: Radio Frequency), etc., or any suitable combination of the above.

[0098] The computer-readable storage medium may be included in the engine control device; or may exist independently without being assembled into the engine control device.

[0099] The above-mentioned computer-readable storage medium carries one or more programs. When the above-mentioned one or more programs are executed by the engine control device, the engine control device: obtains the target speed difference and the target torque change rate when there is a demand for engine start of the target vehicle; determines the target synchronization state according to the target speed difference and the target torque change rate; when the target synchronization state is a synchronization success state, performs gear switching according to the target gear command and the speed and torque adjustment command to obtain the gear switching state; when the gear switching state is a gear switching completion state, starts the engine of the target vehicle.

[0100] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may 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 may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0101] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0102] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0103] The readable storage medium provided by the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned engine control method, and can solve the technical problems such as weak power or slow acceleration and overtaking when accelerating and overtaking on a plateau slope under the condition of low-torque motor and insufficient battery discharge power. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided by the present application are the same as the beneficial effects of the engine control method provided by the above-mentioned embodiment, and will not be repeated here.

[0104] The present application also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the steps of the engine control method as described above are implemented.

[0105] The computer program product provided by the present application can solve the technical problems such as weak power or slow acceleration and overtaking when accelerating and overtaking on a plateau slope under the condition of low-torque motor and insufficient battery discharge power. Compared with the prior art, the beneficial effects of the computer program product provided by the present application are the same as the beneficial effects of the engine control method provided by the above embodiment, which will not be repeated here.

[0106] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. An engine control method, characterized in that: The engine control method comprises: When the target vehicle has an engine start demand, obtaining a target speed difference and a target torque change rate; determining a target synchronization state according to the target speed difference and the target torque change rate; When the target synchronization state is a synchronization success state, the gear switching is performed according to the target gear command and the speed and torque adjustment command to obtain the gear switching state; When the gear switching state is a gear switching completion state, the engine of the target vehicle is started.

2. The method according to claim 1, characterized in that When the target vehicle has an engine start requirement, before obtaining the target speed difference and the target torque change rate, the method further includes: When the target vehicle is in a power activation state and the current vehicle speed is greater than the vehicle speed threshold, the current motor speed, the current vehicle slope and the current wheel torque are obtained; Determine a corresponding current torque threshold according to the current motor speed and the current vehicle slope; When the current wheel-side torque is less than the current torque threshold, it is determined that the target vehicle has an engine start demand.

3. The method according to claim 2, characterized in that The step of obtaining the current wheel torque comprises: When the target vehicle is in pure electric mode, determining the current battery torque according to the current battery power and a preset conversion strategy, and obtaining the motor limit torque; The torque is calculated according to the current battery torque and the motor limit torque to obtain the current wheel torque.

4. The method according to claim 1, characterized in that The determining the target synchronization state according to the target rotation speed difference and the target torque change rate comprises: Comparing the target speed difference with the speed difference threshold to obtain a speed difference comparison result; Comparing the target torque change rate with a torque change rate threshold to obtain a torque change rate comparison result; 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; 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, the target synchronization state is determined to be a synchronization failure state.

5. The method according to claim 1, characterized in that The step of performing gear switching according to the target gear command and the speed and torque adjustment command to obtain the gear switching state includes: Determining 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 adjustment command to obtain the speed regulation required torque; The gear switching is performed without a clutch according to the speed regulation requirement torque, and the gear switching state is determined.

6. The method according to claim 5, characterized in that Performing clutchless gear switching according to the speed regulation required torque and determining the gear switching state includes: Performing gear switching according to the speed regulation required torque to obtain a gear switching position; determining a target position difference according to the gear shift position and the target gear position; The gear switching state is determined according to the target position difference and the position difference threshold.

7. The method according to claim 6, characterized in that The step of determining the gear shift state according to the target position difference and the position difference threshold comprises: Comparing the target position difference with the position difference threshold to obtain a position difference comparison result; When the position difference comparison result is that the target position difference is smaller than the position difference threshold, it is determined that the gear switching state is a gear switching completion state.

8. An engine control device, characterized in that: The device comprises: A processing module, used for obtaining a target speed difference and a target torque change rate when the target vehicle has an engine start demand; The processing module is further used to determine a target synchronization state according to the target speed difference and the target torque change rate; The processing module is further used to perform gear switching according to the target gear instruction and the speed and torque adjustment instruction to obtain the gear switching state when the target synchronization state is a synchronization success state; A starting module is used to start the target vehicle engine when the gear switching state is a gear switching completion state.

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

10. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the engine control method according to any one of claims 1 to 7 are implemented.

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