An electric vehicle driving operation power optimization control method and system

Abstract

The application relates to a kind of electric vehicle driving operation power optimization control method and system, the method includes: with current vehicle speed signal, vehicle speed signal change rate and brake pedal opening degree as the trigger condition input signal of entering road model, only in the road model trigger period start timing, vehicle running condition always satisfies the condition of road model trigger switch setting, the vehicle controller will be optimized control only then.The application establishes road model for the actual driving operation of electric vehicle, can improve economy and increase driving range in actual road condition;After entering road model, through road model driving coefficient, reduce the upper limit value of discharge power, and weaken torque output, increase driving range;Through increasing road model energy recovery coefficient, the energy recovery in coasting and braking process is strengthened, so as to improve economy.

Description

Technical Field

[0001] The present invention relates to the technical field of electric vehicles, and particularly to an electric vehicle driving operation power optimization control method and system. Background Art

[0002] With the development of new energy vehicles, the market pays more and more attention to the energy consumption of the whole vehicle. How to improve the energy utilization efficiency without affecting the driving experience has become a topic. Currently, there are also many technical solutions, but most of them require additional component costs to achieve, such as navigation systems, ADAS, etc. These components increase the use and maintenance costs of end customers. Moreover, the use of new devices and new functions not only increases the complexity of the whole vehicle system in practice, but also requires users to be familiar with the usage methods. Summary of the Invention

[0003] To solve the above problems, the present invention proposes an electric vehicle driving operation power optimization control method and system. The present invention mainly involves that when the vehicle control unit calculates the vehicle control requirements, based on the signal acquisition of existing components, a road model is established through driving operations to optimize the energy consumption of the whole vehicle.

[0004] The technical solution of the present invention is specifically as follows:

[0005] An electric vehicle driving operation power optimization control method uses the current vehicle speed signal, the vehicle speed signal change rate, and the brake pedal opening as the trigger condition input signals to enter the road model. Only when the vehicle driving condition continuously satisfies the road model trigger switch setting within the start timing of the road model trigger period T_RdMod_timer < T:

[0006] RdMod_Swc = (VehSpd_Flt < C1) & (Var_VehSpd < C2) || (Var_Brk > C3), will the road model perform optimization control; that is, it enters the precondition of the relevant control module.

[0007] Where, VehSpd_Flt is the value of the current vehicle speed after Butterworth filtering, Var_VehSpd is the vehicle speed change rate, Var_Brk is the brake pedal opening change rate, T, C1, C2, and C3 are calibrated after actual road tests. Among them, C1 is the vehicle speed threshold, C2 is the vehicle speed change rate threshold, C3 is the pedal change rate threshold, and T is the setting hold time threshold.

[0008] The present invention also relates to an electric vehicle driving operation power optimization control method, including the following steps:

[0009] During the acceleration process, the following is carried out:

[0010] Road model drive coefficient:

[0011] Par_RdMod_Drv=Cd(T1-T0) / T0;

[0012] Among them, the target torque T1 is obtained by looking up the table from the accelerator pedal opening, the current torque T0 is the current actual torque, and Cd is a calibrable constant in the drive coefficient;

[0013] Meanwhile, by multiplying the upper limit of the battery pack discharge power obtained from the lookup table, the upper limit of the discharge power is reduced; without considering other factors, the acceleration in the road model is weakened by increasing the road model driving coefficient.

[0014] During deceleration:

[0015] When the accelerator is released but there is still some opening in the accelerator pedal, the driving coefficient of the road model is as follows:

[0016] Par_RdMod_DrvS=Cd'(T0'-T1') / T0';

[0017] Among them, the target torque T1' is obtained by looking up the table from the accelerator pedal opening, the current torque T0' is the current actual torque, and Cd is a calibrable constant in the drive coefficient;

[0018] At the same time, the upper limit of the discharge power is reduced by multiplying it with the upper limit of the battery pack discharge power obtained by looking up the table; without considering other factors, the torque output of the road model is weakened by increasing the driving coefficient of the road model and reducing the throttle opening for deceleration.

[0019] When braking, the road model's braking energy recovery coefficient is as follows: (This is the value of the coefficient when braking is applied and decelerated by pressing the brake pedal.)

[0020] Par_RdMod_Brk_Rcy=Cc*|(Tb-Tb') / Tb'|;

[0021] Wherein, the target torque Tb is the negative torque corresponding to the brake pedal, used for brake energy recovery, and is obtained by looking up the table from the brake pedal opening. The current torque Tb' is the current actual negative torque, and Cc is a calibrable parameter in the brake energy recovery coefficient.

[0022] Without considering other factors, the braking energy recovery in the road model is enhanced by increasing the energy recovery coefficient.

[0023] Furthermore, during acceleration, without considering other factors, the actual target torque output is:

[0024] Tout = T1 * Par_RdMod_Drv.

[0025] Further, when the accelerator pedal is released and there is still an opening degree, without considering other factors, the actually output target torque Tout = T1' * Par_RdMod_DrvS.

[0026] Further, deceleration also includes: releasing the accelerator pedal and the vehicle is in a coasting state.

[0027] After the accelerator pedal is released and the driver does not step on the brake pedal, but only allows the vehicle to coast forward:

[0028] Tsout = Tsc * Cs * Var_VehSpd,

[0029] where the energy recovery coefficient:

[0030] Par_RdMod_Rcy = Cs * Var_VehSpd;

[0031] Tsout: the actually energy recovery value; Tsc: the calibrated coasting energy recovery value; Cs: the calibratable parameter in the energy recovery coefficient; by increasing the energy recovery coefficient, the energy of coasting deceleration in the road model is strengthened for recovery.

[0032] Further, when braking, without considering other factors, the actually output target negative torque is

[0033] Tout = Tb * Par_RdMod_Brk_Rcy.

[0034] Further, using the current vehicle speed signal, the vehicle speed signal change rate, and the brake pedal opening degree as the trigger condition input signals to enter the road model. Only when within the trigger period of the road model starting to count T_RdMod_timer < T, the vehicle driving condition always satisfies the road model trigger switch being set: RdMod_Swc = (VehSpd_Flt < C1) & (Var_VehSpd < C2) || (Var_Brk > C3); will the road model perform optimization control. Where VehSpd_Flt is the value of the current vehicle speed after Butterworth filtering, Var_VehSpd is the vehicle speed change rate, Var_Brk is the brake pedal opening degree change rate, T, C1, C2, and C3 are calibrated after actual road tests. Among them, C1 is the vehicle speed threshold, C2 is the vehicle speed change rate threshold, C3 is the pedal change rate threshold, and T is the set holding time threshold.

[0035] The present invention also relates to an electric vehicle driving operation power optimization control system, including a vehicle controller and a collector. The vehicle controller includes a vehicle demand power calculation module. The collector collects the driving mode, gear signal, vehicle equipment power consumption, battery management system, accelerator pedal opening degree, brake pedal opening degree, and vehicle speed signal. The road model directly participates in power calculation and actual drive output;

[0036] Obtain the road model drive coefficients Par_RdMod_Drv, Par_RdMod_Drvs and the road model energy recovery coefficients Par_RdMod_Rcy, Par_RdMod_Brk_Rcy; calculate them using the vehicle demand power calculation module according to the method described in any one of claims 1-7, and output them to the drive motor controller, which then controls the drive motor.

[0037] The present invention also relates to a computer system, including a memory, a processor, and a computer program on the memory and executable on the processor, characterized in that: when the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 7.

[0038] This invention establishes a road model for the actual driving operation of electric vehicles without changing the hardware or increasing costs, which can improve economy and increase driving range in actual road conditions.

[0039] After entering the road model, the upper limit of discharge power is reduced and the torque output is weakened by adjusting the road model drive coefficient, thereby increasing the driving range. By increasing the road model energy recovery coefficient, energy recovery during coasting and braking is enhanced, thus improving fuel economy. Attached Figure Description

[0040] Figure 1 This is a system block diagram of the control system according to an embodiment of the present invention;

[0041] Figure 2 This is a flowchart of one control process according to an embodiment of the present invention;

[0042] Figure 3 This is a flowchart of the control process under accelerated state according to an embodiment of the present invention;

[0043] Figure 4 This is a flowchart of the throttle release control process under deceleration conditions according to an embodiment of the present invention;

[0044] Figure 5 This is a flowchart of the braking control process under deceleration conditions according to an embodiment of the present invention. Detailed Implementation

[0045] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0046] Unless otherwise defined, the technical terms or scientific terms used in the embodiments of this application should have the ordinary meanings understood by those of ordinary skill in the relevant field. The "first", "second" and similar terms used in this embodiment do not denote any order, quantity or importance, but are only used to distinguish different components. Words such as "comprising" or "including" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. The terms "mounted", "connected" and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. The terms "upper", "lower", "left", "right", "horizontal" and "vertical" are only relative to the orientation of the components in the drawings. These directional terms are relative concepts, which are used for relative description and clarification, and they can change accordingly according to the change of the orientation of the components placed in the drawings.

[0047] As Figure 1 shown, the driving operation power optimization control system of the electric vehicle in this embodiment includes a vehicle controller and a collector. The vehicle controller includes a vehicle demand power calculation module. The collector collects driving mode, gear signal, vehicle equipment power consumption, battery management system, accelerator pedal opening, brake pedal opening and vehicle speed signal, and inputs them into the vehicle demand power calculation module.

[0048] The road model directly participates in power calculation and actual drive output.

[0049] Construct a road model based on the accelerator pedal opening, brake pedal opening and vehicle speed signal, and obtain the road model drive coefficients Par_RdMod_Drv, Par_RdMod_Drvs and the road model energy recovery coefficients Par_RdMod_Rcy, Par_RdMod_Brk_Rcy.

[0050] As Figure 2 shown, considering that the vehicle speed is not high and the brake pedal is used frequently when the road is congested, use the current vehicle speed signal, the vehicle speed signal change rate and the brake pedal opening as the trigger condition input signal for entering the road model. Only when the road model trigger period starts to count T_RdMod_timer < T, the vehicle driving condition always satisfies the road model trigger switch setting RdMod_Swc = (VehSpd_Flt < C1) & (Var_VehSpd < C2) || (Var_Brk > C3)

[0051] This single condition (T, C1, C2, and C3 can be calibrated after actual road testing, where C1 is the vehicle speed threshold, C2 is the vehicle speed change rate threshold, C3 is the pedal change rate threshold, and T is the position holding time threshold) will cause the vehicle controller to enter the road model for optimized control. In other words, it is a prerequisite for entering the relevant control module.

[0052] In this embodiment, the vehicle controller removes interference signals by performing Butterworth low-pass filtering on the vehicle speed signal, brake pedal signal, and accelerator pedal opening signal. The rate of change of the filtered signal is obtained by comparing it with the same signal from the previous cycle, and then input into the road model to obtain road model coefficients.

[0053] After modeling the road conditions for vehicle driving, the specific calculations of the road model driving coefficients Par_RdMod_Drv and Par_RdMod_Drvs, and the road model energy recovery coefficients Par_RdMod_Rcy and Par_RdMod_Brk_Rcy are as follows: Figure 3 As shown, it can be divided into two working conditions:

[0054] The first operating condition is the acceleration process, such as... Figure 3 As shown:

[0055] Road model driving coefficients:

[0056] Par_RdMod_Drv=Cd(T1-T0) / T0,

[0057] Among them, the target torque T1 is obtained by looking up the table from the accelerator pedal opening, the current torque T0 is the current actual torque, and Cd is a calibrable constant in the drive coefficient.

[0058] Simultaneously, the upper limit of the battery pack discharge power is reduced by multiplying it by the upper limit value of the battery pack discharge power obtained from the lookup table. And, without considering other factors, the actual target torque output is:

[0059] Tout = T1 * Par_RdMod_Drv.

[0060] By increasing the driving coefficient of the road model, the acceleration in the road model is output with reduced torque.

[0061] The second operating condition is the deceleration process, which can be further subdivided into three operating conditions:

[0062] 1) When you release the accelerator, there is still some opening in the accelerator pedal, such as... Figure 4 As shown, the road model driving coefficients are as follows:

[0063] Par_RdMod_DrvS=Cd'(T0'-T1') / T0',

[0064] Among them, the target torque T1' is obtained by looking up the table from the accelerator pedal opening, the current torque T0' is the current actual torque, and Cd is a calibrable constant in the drive coefficient.

[0065] Simultaneously, by multiplying the upper limit of battery pack discharge power obtained from a lookup table, the upper limit of discharge power is reduced. And without considering other factors, the actual target output torque is:

[0066] Tout = T1' * Par_RdMod_DrvS;

[0067] By increasing the driving coefficient of the road model, the torque output is weakened when the throttle opening is reduced in the road model.

[0068] 2) Release the accelerator, and the vehicle will coast.

[0069] After releasing the accelerator, the driver does not apply the brake pedal, but simply allows the vehicle to coast forward.

[0070] Tsout = Tsc * Cs * Var_VehSpd,

[0071] Among them, the energy recovery coefficient is:

[0072] Par_RdMod_Rcy=Cs*Var_VehSpd;

[0073] Tsout: Actual energy recovery value;

[0074] Tsc: Calibrated coasting energy recovery value;

[0075] Cs: A calibrable parameter in the energy recovery coefficient.

[0076] By increasing the energy recovery coefficient, energy recovery is enhanced for coasting deceleration in the road model.

[0077] 3) Apply the brakes

[0078] When decelerating by pressing the brake pedal, the road model's braking energy recovery coefficient is:

[0079] Par_RdMod_Brk_Rcy=Cc*|(Tb-Tb') / Tb'|

[0080] Wherein, the target torque Tb is the negative torque corresponding to the brake pedal, used for brake energy recovery, and is obtained by looking up the table from the brake pedal opening. The current torque Tb' is the current actual negative torque, and Cc is a calibrable parameter in the brake energy recovery coefficient.

[0081] Without considering other factors, the actual target negative torque output is:

[0082] Tout=Tb*Par_RdMod_Brk_Rcy;

[0083] By increasing the energy recovery coefficient, braking energy recovery is enhanced during braking deceleration in the road model.

[0084] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for optimizing the power control of electric vehicle driving operations, characterized in that: Taking the current vehicle speed signal, the vehicle speed signal change rate, and the brake pedal opening as the trigger condition input signals for entering the road model, only when within the triggering period of the road model start timing T_RdMod_timer < T, the vehicle driving condition continuously satisfies the road model trigger switch setting: RdMod_Swc = (VehSpd_Flt < C1) & (Var_VehSpd < C2) || (Var_Brk > C3), will the road model perform optimization control; Among them, VehSpd_Flt is the value of the current vehicle speed after Butterworth filtering, Var_VehSpd is the vehicle speed change rate, Var_Brk is the brake pedal opening change rate, T, C1, C2, and C3 are calibrated after actual road tests. Among them, C1 is the vehicle speed threshold, C2 is the vehicle speed change rate threshold, C3 is the pedal change rate threshold, and T is the setting hold time threshold; During the acceleration process, proceed as follows: Road model drive coefficient: Par_RdMod_Drv = Cd(T1 - T0) / T0; Among them, the target torque T1 is obtained by looking up the table according to the throttle pedal opening, the current torque T0 is the current actual torque, and Cd is a calibratable constant in the drive coefficient; At the same time, by multiplying with the upper limit value of the battery pack discharge power obtained by looking up the table, reduce the upper limit value of the discharge power; without considering other factors, by increasing the road model drive coefficient, perform torque weakening output for the acceleration in the road model; During the deceleration process: When releasing the throttle and the throttle still has an opening, at this time the road model drive coefficient: Par_RdMod_DrvS = Cd’(T0’ - T1’) / T0’; Among them, the target torque T1’ is obtained by looking up the table according to the throttle pedal opening, the current torque T0’ is the current actual torque, and Cd is a calibratable constant in the drive coefficient; At the same time, by multiplying with the upper limit value of the battery pack discharge power obtained by looking up the table, reduce the upper limit value of the discharge power; without considering other factors, by increasing the road model drive coefficient, perform torque weakening output for reducing the throttle opening deceleration in the road model; When stepping on the brake, when decelerating by stepping on the brake pedal, the road model braking energy recovery coefficient: Par_RdMod_Brk_Rcy = Cc*|(Tb - Tb’) / Tb’|; Among them, the target torque Tb is the negative torque corresponding to the brake pedal for braking energy recovery, obtained by looking up the table according to the brake pedal opening, the current torque Tb’ is the current actual negative torque, and Cc is a calibratable parameter in the braking energy recovery coefficient; Without considering other factors, by increasing the energy recovery coefficient, strengthen the braking energy recovery for the braking deceleration in the road model; During the acceleration process, without considering other factors, the actually output target torque: Tout = T1*Par_RdMod_Drv; When releasing the throttle and the throttle still has an opening, without considering other factors, the actually output target torque Tout = T1'*Par_RdMod_DrvS; Deceleration also includes: releasing the throttle, and the vehicle is in a coasting state, After releasing the throttle, the driver does not step on the brake pedal and just lets the vehicle coast forward: Tsout=Tsc*Cs*Var_VehSpd, Among them, the energy recovery coefficient is: Par_RdMod_Rcy=Cs*Var_VehSpd; Tsout: Actual energy recovery value; Tsc: Calibrated coasting energy recovery value; Cs: Calibrable parameter in the energy recovery coefficient; By increasing the energy recovery coefficient, energy recovery is enhanced for coasting deceleration in the road model; When braking, without considering other factors, the actual output target negative torque is Tout = Tb * Par_RdMod_Brk_Rcy.

2. A power optimization control system for electric vehicle driving operation, characterized in that: It includes a vehicle controller and a data acquisition unit. The vehicle controller includes a vehicle power demand calculation module. The data acquisition unit collects driving mode, gear signal, power consumption of vehicle equipment, battery management system, accelerator pedal opening, brake pedal opening and vehicle speed signal. The road model directly participates in power calculation and actual drive output. Obtain the road model driving coefficients Par_RdMod_Drv, Par_RdMod_Drvs and the road model energy recovery coefficients Par_RdMod_Rcy, Par_RdMod_Brk_Rcy; calculate them using the vehicle demand power calculation module according to the method described in claim 1, and output them to the drive motor controller, which then controls the drive motor.

3. A computer system comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, it implements the steps of the method described in claim 1.

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