Driving control method and system of hybrid vehicle

Abstract

The invention discloses a driving control method and system of a hybrid power vehicle. The method comprises the steps that operation parameters of the vehicle are collected; theoretical change values of the motor torque and the engine torque are calculated; obtaining an execution difference ratio between the target torque of the motor and the target torque of the engine; calculating an engine torque change coordination value; calculating a motor torque change coordination value; the executed target torque of the motor or the engine in the current task period is calculated and used for judging the execution state of the control method; if it is judged that the state is the torque coordination state, the current motor torque or the current engine torque is regulated and controlled based on the change coordination value of the motor torque or the engine torque; otherwise, the target torque executed by the motor or the engine in the last task period is updated to be the target torque executed by the motor or the engine in the current task period, and the control method is executed again after the preset task period. The problem of torque jitter generated when the hybrid electric vehicle controls the engine and the driving motor at the same time can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle control, and in particular to a driving control method and system for a hybrid vehicle. Background Art

[0002] A hybrid vehicle is a vehicle that adds a drive motor to assist in driving a traditional fuel vehicle, which can improve the vehicle's fuel economy and power. However, a hybrid vehicle needs to control the engine and the drive motor at the same time to output power, which easily generates torque jitter in the process and causes the problem of vehicle ride quality. How to avoid torque jitter and achieve coordinated control of the engine and the drive motor has become a key technical problem that hybrid vehicles need to solve urgently. Based on this situation, the present invention proposes a driving control method and system for a hybrid vehicle. Summary of the invention

[0003] The main purpose of the present invention is to provide a driving control method and system for a hybrid vehicle, so as to solve the torque jitter problem generated when the hybrid vehicle controls the engine and the drive motor at the same time.

[0004] The technical solution adopted by the present invention is: a driving control method for a hybrid vehicle, comprising:

[0005] Collect vehicle operating parameters;

[0006] Based on the vehicle's operating parameters, the theoretical change values ​​of the motor torque and the engine torque, the motor target torque execution difference, and the engine target torque execution difference are calculated respectively, and the execution difference ratio of the motor target torque to the engine target torque is obtained;

[0007] Calculating the engine torque change coordination value based on the execution difference ratio of the motor torque and the engine torque, the motor torque and the theoretical change value of the engine torque; calculating the motor torque change coordination value based on the engine torque change coordination value, the execution difference ratio of the motor target torque and the engine target torque;

[0008] Calculate the executed target torque of the current task cycle of the motor or the engine based on the change coordination value of the motor torque or the engine torque;

[0009] Determine the execution state of the control method based on the target torque that the motor and the engine have executed in the current task cycle;

[0010] If it is judged to be a torque coordination state, the current motor torque or engine torque is regulated based on the change coordination value of the motor torque or engine torque; if it is judged to be a non-torque coordination state, the target torque executed by the motor or engine in the previous task cycle is updated to the target torque executed by the motor or engine in the current task cycle, and this control method is re-executed after an interval of a preset task cycle.

[0011] According to the above technical solution, the operating parameters also include: acceleration change rate limit, vehicle unloaded mass, wheel radius, vehicle transmission ratio, maximum change of engine load per unit time, maximum mechanical change capacity of motor torque per unit time, maximum mechanical change capacity of engine torque per unit time, steady-state target torque of engine, steady-state target torque of motor. Further, the above parameters can be obtained based on actual measurement, calibration or empirical values.

[0012] According to the above technical solution, the method for calculating the theoretical change value of the motor torque includes:

[0013] Calculate the upper limit of the vehicle driving torque change based on the acceleration change rate limit, the vehicle unloaded mass, the wheel radius, the vehicle transmission ratio and the mission cycle;

[0014] The upper limit of the motor torque change is calculated based on the maximum allowable change of the engine load per unit time and the maximum mechanical change capacity of the motor torque per unit time;

[0015] Calculate the vehicle driving torque variation capability based on the upper limit of the motor torque variation and the maximum mechanical variation capability of the engine torque per unit time;

[0016] Calculate the motor torque change ratio based on the vehicle's driving torque change capability and the motor torque change upper limit;

[0017] The theoretical change value of the motor torque is calculated based on the motor torque change proportion, the upper limit of the vehicle drive torque change, the upper limit of the motor torque change, and the task cycle.

[0018] According to the above technical solution, the method for calculating the theoretical change value of the engine torque includes:

[0019] Calculating the engine torque change ratio based on the maximum mechanical change capability of the engine torque per unit time and the vehicle driving torque change capability;

[0020] The theoretical change value of the engine torque is calculated based on the engine torque change proportion, the upper limit value of the vehicle drive torque change, the maximum mechanical change capacity of the engine torque per unit time and the task cycle.

[0021] According to the above technical solution, the calculation method of the upper limit of the vehicle driving torque change includes: the upper limit of the vehicle driving torque change is equal to the acceleration change rate limit multiplied by the vehicle unloaded mass multiplied by the wheel radius multiplied by the task cycle divided by the vehicle transmission ratio;

[0022] The method for calculating the upper limit of the motor torque variation includes: the upper limit of the motor torque variation is equal to the smaller value of the maximum variation of the engine allowable load and the maximum mechanical variation capacity of the motor torque;

[0023] The method for calculating the vehicle driving torque variation capability includes: the vehicle driving torque variation capability is equal to the motor torque variation upper limit value plus the maximum mechanical variation capability of the engine torque per unit time.

[0024] According to the above technical solution, the calculation method of the motor torque change ratio includes: the motor torque change ratio is equal to the motor torque change upper limit divided by the vehicle driving torque change capacity;

[0025] The calculation method of the motor torque theoretical change value includes: the motor torque theoretical change value is equal to the smaller value of the motor torque change upper limit value multiplied by the task cycle and the motor torque change ratio multiplied by the vehicle drive torque change upper limit value.

[0026] According to the above technical solution, the method for calculating the engine torque change ratio includes:

[0027] The engine torque change ratio is equal to the maximum mechanical change capacity of the engine torque per unit time divided by the vehicle drive torque change capacity.

[0028] The calculation method of the theoretical change value of the engine torque includes: the theoretical change value of the engine torque is equal to the smaller value of the value obtained by multiplying the maximum mechanical change capacity of the engine torque per unit time by the task cycle and the value obtained by multiplying the engine torque change ratio by the upper limit value of the vehicle drive torque change.

[0029] According to the above technical solution, the method for calculating the target torque execution difference of the motor includes: the target torque execution difference of the motor is equal to the steady-state target torque of the motor minus the target torque executed by the motor in the previous task cycle;

[0030] The method for calculating the target torque execution difference of the engine includes: the target torque execution difference of the engine is equal to the steady-state target torque of the engine minus the target torque that has been executed by the engine in the previous task cycle.

[0031] According to the above technical solution, the calculation method of the execution difference ratio of the motor and engine torque includes: the execution difference ratio of the motor and engine torque is equal to the absolute value of the execution difference of the motor target torque divided by the execution difference of the engine target torque.

[0032] According to the above technical solution, the calculation method of the engine torque change coordination value includes: the engine torque change coordination value is equal to the motor torque theoretical change value divided by the smaller value of the motor and engine torque execution difference ratio and the engine torque theoretical change value multiplied by the sign of the engine target torque execution difference;

[0033] When the target torque execution difference of the engine is not less than 0, the sign of the target torque execution difference of the engine is equal to 1; when the target torque execution difference of the engine is less than 0, the sign of the target torque execution difference of the engine is equal to -1.

[0034] According to the above technical solution, the calculation method of the motor torque change coordination value includes: the motor torque change coordination is equal to the absolute value of the engine torque change coordination value multiplied by the execution difference ratio of the motor and engine torques and then multiplied by the target torque execution difference sign of the motor;

[0035] When the target torque execution difference of the motor is not less than 0, the sign of the target torque execution difference of the motor is equal to 1; when the target torque execution difference of the motor is less than 0, the sign of the target torque execution difference of the motor is equal to -1.

[0036] According to the above technical solution, the method for calculating the target torque executed by the motor in the current task cycle includes: the target torque executed by the motor in the current task cycle is equal to the target torque executed by the motor in the previous task cycle plus the motor torque change coordination value;

[0037] The method for calculating the target torque executed by the engine in the current task cycle includes: the target torque executed by the engine in the current task cycle is equal to the target torque executed by the engine in the previous task cycle plus the engine torque change coordination value.

[0038] According to the above technical solution, the method for determining the execution status of the control method includes:

[0039] Respectively comparing the target torque executed by the engine in the current task cycle and the steady-state target torque of the engine, and the target torque executed by the motor in the current task cycle and the steady-state target torque of the motor;

[0040] If both are the same, it is determined to be a torque coordinated state. If either of them is different, it is determined to be a torque non-coordinated state.

[0041] Another aspect of the present invention provides a hybrid vehicle driving control system, which executes the hybrid vehicle driving control method described above.

[0042] The beneficial effect produced by the present invention is: the driving control method and system of the hybrid vehicle provided by the present invention coordinates the execution difference of the motor and engine torque by setting the engine torque change coordination value and the motor torque change coordination value, so as to achieve the engine and the motor to reach their set target torque at the same time, avoid torque jitter, and improve the smoothness of the vehicle.

[0043] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 is a flow chart of a driving control method of a hybrid vehicle according to an embodiment of the present invention;

[0046] Figure 2 It is a step chart of a driving control method of a hybrid vehicle according to an embodiment of the present invention. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0048] It should be noted that the illustrations provided in the embodiments of the present invention are only used to illustrate the basic concept of the present invention in a schematic manner. Therefore, the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout type may also be more complicated.

[0049] In the present invention, it is also necessary to explain that, if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, if the terms "first" and "second" appear, they are only used for description and distinction purposes, and cannot be understood as indicating or implying relative importance.

[0050] Example 1

[0051] This embodiment provides a driving control method for a hybrid vehicle, the process is as follows: Figure 1 As shown, the steps include:

[0052] S1. Collect the vehicle's operating parameters, including the target torque T1(k-1) that the motor has executed in the previous task cycle. motor and the target torque T1(k-1) that the engine has executed in the previous task cycle engine.

[0053] Specifically, the operating parameters also include: acceleration rate limit The vehicle's unloaded mass m, wheel radius r, vehicle transmission ratio i, and the maximum change in engine load per unit time ΔT engineallowmax , the maximum mechanical change capacity of the motor torque per unit time ΔT1 motormax , the maximum mechanical change capacity of the engine torque per unit time ΔT enginemax 、The engine's steady-state target torque T engine , the steady-state target torque T of the motor motor . Among them, ΔT engineallowmax , ΔT1 motormax , ΔT enginemax The above parameters can be obtained through bench testing or empirical values.

[0054] S2. Calculate the theoretical change value ΔT1 of the motor torque respectively motor , Theoretical change value of engine torque ΔT1 engine , the execution difference of the motor target torque ΔT motor The difference between the target torque of the engine and the target torque of the engine is ΔT engine , the execution difference ratio β between the motor target torque and the engine target torque is obtained motoengine .

[0055] S201, calculate the theoretical change value ΔT1 of the motor torque motor and the theoretical change in engine torque ΔT1 engine .

[0056] Specifically, the theoretical change value ΔT1 of the motor torque is calculated motor The process includes:

[0057] Based on jerk limiting The upper limit of the vehicle driving torque change ΔT is calculated based on the vehicle unloaded mass m, wheel radius r, vehicle transmission ratio i and task cycle Δt. all ,

[0058]

[0059] That is, the upper limit of the vehicle driving torque change ΔT all Equal to the acceleration rate limit Multiply by the vehicle's unloaded mass m, multiply by the wheel radius r, multiply by the task cycle Δt, and then divide by the vehicle's transmission ratio i.

[0060] Based on the maximum change in engine load per unit time ΔT engineallowmax , the maximum mechanical change capacity of the motor torque per unit time ΔT1motormax Calculate the upper limit of motor torque change ΔT motormax ,

[0061] ΔT motormax =min(ΔT engineallowmax , ΔT1 motormax )

[0062] That is, the upper limit of the motor torque change ΔT motormax Equal to the maximum change in engine load ΔT engineallowmax The maximum mechanical change capability of the motor torque ΔT1 motormax The smaller value of .

[0063] Based on the upper limit of motor torque change ΔT motormax , the maximum mechanical change capacity of the engine torque per unit time ΔT enginemax Calculate the vehicle driving torque variation capability ΔT max ,

[0064] ΔT max =ΔT motormnax +ΔT enginemax

[0065] That is, the vehicle driving torque variation capability ΔT max Equal to the upper limit of the motor torque change ΔT motormax Plus the maximum mechanical change capacity of the engine torque per unit time ΔT enginemax .

[0066] Based on the vehicle's driving torque variation capability ΔT max , Motor torque change upper limit ΔT motormax Calculate the motor torque change ratio γ motormax ,

[0067]

[0068] That is, the motor torque change ratio γ motormax Equal to the upper limit of the motor torque change ΔT motormax Divided by the vehicle's driving torque variation capability ΔT max .

[0069] Based on the proportion of motor torque change γ motormax , the upper limit of vehicle driving torque change ΔT all , Motor torque change upper limit ΔT motormax , calculate the theoretical change value of motor torque ΔT1 based on the task cycle Δt motor ,

[0070] ΔT1 motor =min(γ motormax *ΔT all , ΔTmotormax *Δt)

[0071] That is, the theoretical change value of the motor torque ΔT1 motor Equal to the upper limit of the motor torque change ΔT all Multiply the value obtained by the task cycle Δt and the motor torque change ratio γ motormax Multiply by the upper limit of vehicle drive torque change ΔT all The smaller of the resulting values.

[0072] Calculate the theoretical change in engine torque ΔT1 engine The process includes:

[0073] The vehicle driving torque variation capability ΔT is obtained from the above calculation process max .

[0074] Based on the maximum mechanical change capacity of the engine torque per unit time ΔT enginemax , the vehicle driving torque variation capability ΔT max Calculate the engine torque change ratio γ enginemax ,

[0075]

[0076] That is, the engine torque change ratio γ enginemax Equal to the maximum mechanical change capacity of the engine torque per unit time ΔT enginemax Divided by the vehicle's driving torque variation capability ΔT max .

[0077] Based on the proportion of engine torque change γ enginemax , the upper limit value of the vehicle driving torque change ΔT max , the maximum mechanical change capacity of the engine torque per unit time ΔT enginemax Calculate the theoretical change of engine torque ΔT1 using the task cycle Δt engine ,

[0078] ΔT1 engine =min(γ enginemax *ΔT all , ΔT enginemax *Δt)

[0079] That is, the theoretical change value of engine torque ΔT1 engine Equal to the maximum mechanical change capacity of the engine torque per unit time ΔT enginemax Multiply the value obtained by the task cycle Δt and the engine torque change ratio γ enginemax Multiply by the upper limit of vehicle drive torque change ΔT max The smaller of the resulting values.

[0080] S202, calculating the execution difference ΔT of the motor target torque motor The difference between the target torque of the engine and the target torque of the engine is ΔT engine .

[0081] Specifically, the execution difference ΔT of the motor target torque is calculated motor The process includes:

[0082] Based on the steady-state target torque T of the motor motor 、The target torque T1(k-1) that the motor has executed in the previous task cycle motor Calculate the motor target torque execution difference ΔT motor ,

[0083] ΔT motor =T motor -T1(k-1) motor

[0084] That is, the motor's target torque execution difference ΔT motor Equal to the steady-state target torque T of the motor motor Subtract the target torque T1(k-1) that the motor has executed in the previous task cycle motor .

[0085] Calculate the engine target torque execution difference ΔT engine The process includes:

[0086] Based on the engine's steady-state target torque T engine 、The target torque T1(k-1) that the engine has executed in the previous task cycle engine Calculate the engine target torque execution difference ΔT engine ,

[0087] ΔT engine =T engine -T1(k-1) engine

[0088] That is, the execution difference of the engine target torque ΔT engine Equal to the steady-state target torque T of the engine engine Subtract the target torque T1(k-1) that the engine has executed in the previous task cycle engine .

[0089] S203, calculating the execution difference ratio β between the motor target torque and the engine target torque motoengine .

[0090] Specifically, based on the target torque execution difference ΔT of the motor motor The difference between the target torque of the engine and the target torque of the engine is ΔT engine Calculate the execution difference ratio β between the motor target torque and the engine target torque motoengine ,

[0091]

[0092] That is, the difference between the motor and engine torque is equal to the motor target torque and the engine target torque. motor Divide by the engine target torque execution difference ΔT engine Take the absolute value.

[0093] S3, based on the execution difference ratio β between the motor target torque and the engine target torque motoengine , Theoretical change value of motor torque ΔT1 motor and the theoretical change in engine torque ΔT1 engine Calculate the engine torque change coordination value ΔT2 engine ; Based on the engine torque change coordination value ΔT2 engine , the execution difference ratio β between the motor target torque and the engine target torque motoengine Calculate the motor torque change coordination value ΔT2 motor .

[0094] Specifically, S301, calculate the engine torque change coordination value ΔT2 engine The specific method is:

[0095]

[0096] That is, the engine torque change coordination value ΔT2 engine Equal to the theoretical change value of motor torque ΔT1 motor Divided by the execution difference ratio β between the motor target torque and the engine target torque motoengine The obtained value is equal to the theoretical change value of engine torque ΔT1 engine The smaller value is then multiplied by the sign of the engine's target torque execution difference s (ΔT engine ).

[0097] Furthermore, the sign of the target torque execution difference of the engine is s(ΔT engine ) Specifically,

[0098]

[0099] That is, when the execution difference of the engine target torque is ΔT engine When it is not less than 0, the target torque execution difference of the engine is marked with a sign s (ΔT engine ) is equal to 1; when the target torque execution difference ΔT of the engine engine When it is less than 0, the target torque execution difference of the engine is indicated by the sign s (ΔT engine ) is equal to -1.

[0100] S302, based on the engine torque change coordination value ΔT2 obtained in step S301 engine Calculate the motor torque change coordination value ΔT2 motor The specific method is:

[0101] &ΔT2 motor =|ΔT2 engine |*β motoengine *s(ΔT motor )

[0102] That is, the motor torque change coordination value ΔT2 motor Equal to the engine torque change coordination value ΔT2 engine The absolute value of the motor torque multiplied by the execution difference ratio β between the motor and the engine torque motoengine Then multiply it by the motor's target torque execution difference symbol s(ΔT motor ).

[0103] Furthermore, the target torque of the motor is executed as a differential symbol s(ΔT motor ) Specifically,

[0104]

[0105] That is, when the motor's target torque execution difference ΔT motor When the target torque of the motor is not less than 0, the sign mark s (ΔT motor ) is equal to 1; when the motor's target torque execution difference ΔT motor When the target torque of the motor is less than 0, the sign of the difference in the execution of the target torque of the motor is s(ΔT motor ) is equal to -1.

[0106] S4, based on the change in motor torque coordination value ΔT2 motor And the executed target torque T1(k-1) of the motor in the previous task cycle motor Calculate the executed target torque T1(k) of the motor in the current task cycle motor ; Based on the engine torque change coordination value ΔT2 engine And the executed target torque T1(k-1) of the motor in the previous task cycle motor Calculate the executed target torque T1(k) of the engine in the current task cycle engine , and determine the execution status of this control method.

[0107] S401, calculate the executed target torque T1(k) of the motor in the current task cycle motor and the executed target torque T1(k) of the engine in the current task cycle engine .

[0108] Specifically, calculate the executed target torque T1(k) of the motor in the current task cyclemotor The method is:

[0109] T1(k) motor =T1(k-1) motor +ΔT2 motor

[0110] That is, the target torque T1(k) that the motor has executed in the current task cycle motor Equal to the target torque T1(k-1) executed by the motor in the previous task cycle motor Plus the change in motor torque coordination value ΔT2 motor .

[0111] Calculate the executed target torque T1(k) of the engine in the current task cycle engine The method is:

[0112] T1(k) engine =T1(k-1) engine +ΔT2 engine

[0113] That is, the target torque T1(k) that the engine has executed in the current task cycle engine Equal to the target torque T1(k-1) that the engine has executed in the previous task cycle engine Add the engine torque change coordination value ΔT2 engine .

[0114] S402: Based on the executed target torque T1(k) of the engine in the current task cycle engine 、The executed target torque T1(k) of the motor in the current task cycle motor 、The engine's steady-state target torque T engine and the steady-state target torque T of the motor motor Determine the execution status of this control method.

[0115] Specifically, if the target torque T1(k) of the engine in the current task cycle is engine Equal to the steady-state target torque T of the engine engine And the executed target torque T1(k) of the motor in the current task cycle motor Equal to the steady-state target torque T of the motor motor , it is judged to be in torque coordination state. If the target torque T1(k) of the engine in the current task cycle is engine Not equal to the engine's steady-state target torque T engine Or the executed target torque T1(k) of the motor in the current task cycle motor Not equal to the steady-state target torque T of the motor motor, it is determined that it is not in a torque coordination state. The torque coordination state refers to a working state in which the engine and the motor can simultaneously reach their set target torques.

[0116] S5. If it is determined to be a torque coordination state, the current motor torque or engine torque is regulated based on the change coordination value of the motor torque or engine torque. If it is determined to be a non-torque coordination state, the target torque executed by the motor or engine in the previous task cycle is updated as the target torque executed by the motor or engine in the current task cycle, and the control method is re-executed after a preset task cycle.

[0117] The purpose of implementing this step is to verify whether the engine and the motor coordinate the torque, and to loop this control method when the engine and the motor fail to coordinate the torque until torque synchronization is achieved.

[0118] Example 2

[0119] This embodiment provides another driving control method for a hybrid vehicle. The steps of the method are as follows: Figure 2 shown.

[0120] T1, calculate the upper limit of the vehicle driving torque change ΔT all .

[0121] Specifically, based on the acceleration rate limit Calculate the upper limit of vehicle driving torque change ΔT all .

[0122] T2. Calculate the upper limit of the motor torque change ΔT motormax .

[0123] Specifically, based on the maximum change in engine load per unit time ΔT engineallowmax , the maximum mechanical change capacity of the motor torque per unit time ΔT1 motormax Calculate the upper limit of motor torque change ΔT motormax .

[0124] T3. Calculate the vehicle driving torque variation capability ΔT max .

[0125] Specifically, based on the motor torque change upper limit ΔT motormax , Maximum mechanical change capacity of engine torque per unit time ΔT1 motormax Calculate the vehicle driving torque variation capability ΔT max .

[0126] T4. Calculate the motor torque change ratio γ motormax and engine torque change ratio γ enginemax .

[0127] Specifically, based on the vehicle driving torque variation capability ΔT max , Motor torque change upper limit ΔT motormax , the maximum mechanical change capacity of the engine torque per unit time ΔT enginemax Calculate the motor torque change ratio γ motormax and engine torque change ratio γ enginemax .

[0128] T5. Calculate the theoretical change value of motor torque ΔT1 motor and the theoretical change of engine torque ΔT1 engine .

[0129] Specifically, based on the motor torque change ratio γ motormax , engine torque change ratio γ enginemax , the upper limit of vehicle driving torque change ΔT all , Motor torque change upper limit ΔT motormax , Maximum mechanical change capacity of engine torque per unit time ΔT1 motormax Calculate the theoretical change value of motor torque ΔT1 using the task cycle Δt motor and the theoretical change of engine torque ΔT1 engine .

[0130] T6. Calculate the target torque execution difference ΔT of the engine engine The difference between the motor's target torque and the motor's target torque is ΔT. motor .

[0131] Specifically, based on the steady-state target torque ΔT of the engine engine , the steady-state target torque T of the motor motor 、The target torque T1(k-1) that the engine has executed in the previous task cycle engine 、The target torque T1(k-1) that the motor has executed in the previous task cycle motor Calculate the target torque execution difference ΔT of the engine engine The difference between the motor's target torque and the motor's target torque is ΔT. motor .

[0132] T7, calculate the execution difference ratio β between the motor and engine torque motoengine .

[0133] Specifically, based on the target torque execution difference ΔT of the engine engine The difference between the motor's target torque and the motor's target torque is ΔT. motor Calculate the difference between the motor and engine torque execution ratio β motoengine .

[0134] T8, calculate the engine torque change coordination value ΔT2 engine And the motor torque change coordination value ΔT2motor .

[0135] Specifically, based on the execution difference ratio β between the motor and the engine torque motoengine , Theoretical change value of motor torque ΔT1 motor and the theoretical change of engine torque ΔT1 engine , the sign of the engine's target torque execution difference s(ΔT engine ) and the motor's target torque execution difference sign s(ΔT motor ) Calculate the engine torque change coordination value ΔT2 engine And the motor torque change coordination value ΔT2 motor .

[0136] T9, calculate the target torque T1(k-1) that the engine has executed in the current task cycle engine And the target torque T1(k-1) that the motor has executed in the current task cycle motor .

[0137] Specifically, based on the target torque T1(k-1) that the engine has executed in the previous task cycle engine 、The target torque T1(k-1) that the motor has executed in the previous task cycle motor , Engine torque change coordination value ΔT2 engine And the motor torque change coordination value ΔT2 motor Calculate the target torque T1(k) that the engine has executed in the current task cycle engine and the target torque T1(k) that the motor has executed in the current task cycle motor .

[0138] T10. Determine the program execution status.

[0139] Specifically, based on the target torque T1(k) that the engine has executed in the current task cycle engine 、The target torque T1(k) that the motor has executed in the current task cycle motor , the engine's steady-state target torque ΔT engine and the steady-state target torque T of the motor motor Determine the program execution status.

[0140] If the target torque T1(k) has been executed by the engine in the current task cycle engine Equal to the engine's steady-state target torque ΔT engine And the target torque T1(k) that the motor has executed in the current task cycle motor Equal to the steady-state target torque T of the motor motor The execution ends; if the target torque T1(k) has been executed by the engine in the current task cycle engine Not equal to the engine's steady-state target torque ΔTengine Or the target torque T1(k) that the motor has executed in the current task cycle motor Not equal to the steady-state target torque T of the motor motor , then update the target torque T1(k-1) that the motor has executed in the previous task cycle motor The target torque T1(k) that the motor has executed in the current task cycle motor , the target torque T1(k-1) that the engine has executed in the previous task cycle engine The target torque T1(k) that the engine has executed in the current task cycle engine , and then after an interval of task period Δt, jump to step T6 and start execution again.

[0141] Among them, the upper limit value of the vehicle driving torque change ΔT all , Motor torque change upper limit ΔT motormax , vehicle driving torque variation capability ΔT enginemax , Motor torque change ratio γ motormax , engine torque change ratio γ enginemax , Theoretical change value of motor torque ΔT1 motor , Theoretical change of engine torque ΔT1 engine , Engine target torque execution difference ΔT engine , the motor's target torque execution difference ΔT motor , the execution difference ratio of the motor and engine torque β motoengine , Engine torque change coordination value ΔT2 engine , Motor torque change coordination value ΔT2 motor 、The target torque T1(k) that the engine has executed in the current task cycle engine 、The target torque T1(k) that the motor has executed in the current task cycle motor The specific calculation method of is the same as that in Example 1.

[0142] Example 3

[0143] This embodiment provides a driving control system for a hybrid vehicle, which executes the driving control method for the hybrid vehicle in the first or second embodiment.

[0144] In summary, the present invention provides a driving control method and system for a hybrid vehicle, which obtains the execution difference ratio of the motor and engine torque, and sets the engine torque change coordination value and the motor torque change coordination value according to the execution difference ratio, so as to adjust the executed target torque of the motor in the current task cycle and the executed target torque of the engine in the task cycle, so that they can reach the set steady-state target torque at the same time, thereby avoiding torque jitter and improving the smoothness of the vehicle.

[0145] It should be pointed out that, according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, and two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.

[0146] The order of execution of each step in the above embodiment does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present application.

[0147] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should fall within the scope of protection of the appended claims of the present invention.

Claims

1. A driving control method for a hybrid vehicle, characterized in that: include: Collecting the vehicle's operating parameters, including the target torque that the motor or engine has achieved in the previous mission cycle; Based on the vehicle's operating parameters, the theoretical change values ​​of the motor torque and the engine torque, the motor target torque execution difference, and the engine target torque execution difference are calculated respectively, and the execution difference ratio of the motor target torque to the engine target torque is obtained; Calculating the engine torque change coordination value based on the execution difference ratio between the motor target torque and the engine target torque, and the theoretical change values ​​of the motor torque and the engine torque; Calculating the motor torque change coordination value based on the engine torque change coordination value and the execution difference ratio between the motor target torque and the engine target torque; Calculating the target torque that has been executed in the current task cycle of the motor or the engine based on the change coordination value of the motor torque or the engine torque, which is used to determine the execution state of the control method; If it is judged to be a torque coordination state, the motor torque or engine torque is regulated based on the target torque executed by the motor or engine in the current task cycle; if it is judged to be a non-torque coordination state, the target torque executed by the motor or engine in the previous task cycle is updated as the target torque executed by the motor or engine in the current task cycle, and this control method is re-executed after an interval of a preset task cycle.

2. The driving control method of a hybrid vehicle according to claim 1, characterized in that: The operating parameters also include: acceleration change rate limit, vehicle unloaded mass, wheel radius, vehicle transmission ratio, maximum allowable engine load change per unit time, maximum mechanical change capacity of motor torque per unit time, maximum mechanical change capacity of engine torque per unit time, steady-state target torque of the engine, and steady-state target torque of the motor.

3. The driving control method of a hybrid vehicle according to claim 2, characterized in that: The method for calculating the theoretical change value of the motor torque includes: Calculate the upper limit of the vehicle driving torque change based on the acceleration change rate limit, the vehicle unloaded mass, the wheel radius, the vehicle transmission ratio and the mission cycle; The upper limit of the motor torque change is calculated based on the maximum allowable change of the engine load per unit time and the maximum mechanical change capacity of the motor torque per unit time; Calculate the vehicle driving torque variation capability based on the upper limit of the motor torque variation and the maximum mechanical variation capability of the engine torque per unit time; Calculate the motor torque change ratio based on the vehicle's driving torque change capability and the motor torque change upper limit; The theoretical change value of the motor torque is calculated based on the motor torque change proportion, the upper limit of the vehicle drive torque change, the upper limit of the motor torque change, and the task cycle.

4. The driving control method of a hybrid vehicle according to claim 3, characterized in that: The method for calculating the theoretical change value of the engine torque comprises: Calculating the engine torque change ratio based on the maximum mechanical change capability of the engine torque per unit time and the vehicle driving torque change capability; The theoretical change value of the engine torque is calculated based on the engine torque change proportion, the upper limit value of the vehicle drive torque change, the maximum mechanical change capacity of the engine torque per unit time and the task cycle.

5. The driving control method of a hybrid vehicle according to claim 4, characterized in that: The method for calculating the upper limit of the vehicle driving torque variation includes: the upper limit of the vehicle driving torque variation is equal to the acceleration variation rate limit multiplied by the vehicle unloaded mass multiplied by the wheel radius multiplied by the mission cycle divided by the vehicle transmission ratio; The method for calculating the upper limit of the motor torque variation includes: the upper limit of the motor torque variation is equal to the smaller value of the maximum variation of the engine allowable load and the maximum mechanical variation capacity of the motor torque; The method for calculating the vehicle driving torque variation capability includes: the vehicle driving torque variation capability is equal to the motor torque variation upper limit value plus the maximum mechanical variation capability of the engine torque per unit time.

6. The driving control method of a hybrid vehicle according to claim 3, characterized in that: The calculation method of the motor torque change ratio includes: the motor torque change ratio is equal to the motor torque change upper limit divided by the vehicle driving torque change capacity; The calculation method of the motor torque theoretical change value includes: the motor torque theoretical change value is equal to the smaller value of the motor torque change upper limit value multiplied by the task cycle and the motor torque change ratio multiplied by the vehicle drive torque change upper limit value.

7. The driving control method of a hybrid vehicle according to claim 4, characterized in that: The method for calculating the engine torque change ratio includes: The engine torque change ratio is equal to the maximum mechanical change capacity of the engine torque per unit time divided by the vehicle drive torque change capacity. The calculation method of the theoretical change value of the engine torque includes: the theoretical change value of the engine torque is equal to the smaller value of the value obtained by multiplying the maximum mechanical change capacity of the engine torque per unit time by the task cycle and the value obtained by multiplying the engine torque change ratio by the upper limit value of the vehicle drive torque change.

8. The driving control method of a hybrid vehicle according to claim 2, characterized in that: The method for calculating the target torque execution difference of the motor includes: the target torque execution difference of the motor is equal to the steady-state target torque of the motor minus the target torque that has been executed by the motor in the previous task cycle; The method for calculating the target torque execution difference of the engine includes: the target torque execution difference of the engine is equal to the steady-state target torque of the engine minus the target torque that has been executed by the engine in the previous task cycle.

9. The driving control method of a hybrid vehicle according to claim 1, characterized in that: The method for calculating the execution difference ratio of the motor torque and the engine torque includes: the execution difference ratio of the motor torque and the engine torque is equal to the absolute value of the execution difference of the motor target torque divided by the execution difference of the engine target torque.

10. The driving control method of a hybrid vehicle according to claim 2, characterized in that: The calculation method of the engine torque change coordination value includes: the engine torque change coordination value is equal to the motor torque theoretical change value divided by the smaller value of the motor and engine torque execution difference ratio obtained and the engine torque theoretical change value multiplied by the sign of the engine target torque execution difference; When the target torque execution difference of the engine is not less than 0, the sign of the target torque execution difference of the engine is equal to 1; when the target torque execution difference of the engine is less than 0, the sign of the target torque execution difference of the engine is equal to -1.

11. The driving control method of a hybrid vehicle according to claim 2, characterized in that: The calculation method of the motor torque change coordination value includes: the motor torque change coordination is equal to the absolute value of the engine torque change coordination value multiplied by the execution difference ratio of the motor and engine torques and then multiplied by the target torque execution difference sign of the motor; When the target torque execution difference of the motor is not less than 0, the sign of the target torque execution difference of the motor is equal to 1; when the target torque execution difference of the motor is less than 0, the sign of the target torque execution difference of the motor is equal to -1.

12. The driving control method of a hybrid vehicle according to claim 2, characterized in that: The method for calculating the target torque executed by the motor in the current task cycle includes: the target torque executed by the motor in the current task cycle is equal to the target torque executed by the motor in the previous task cycle plus the motor torque change coordination value; The method for calculating the target torque executed by the engine in the current task cycle includes: the target torque executed by the engine in the current task cycle is equal to the target torque executed by the engine in the previous task cycle plus the engine torque change coordination value.

13. The driving control method of a hybrid vehicle according to claim 2, characterized in that: The method for determining the execution status of the control method includes: Respectively comparing the target torque executed by the engine in the current task cycle and the steady-state target torque of the engine, and the target torque executed by the motor in the current task cycle and the steady-state target torque of the motor; If both are the same, it is determined to be a torque coordinated state. If either of them is different, it is determined to be a torque non-coordinated state.

14. A driving control system for a hybrid vehicle, characterized in that: The system executes the driving control method of a hybrid vehicle as described in any one of claims 1-13.

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