CN102267459B

CN102267459B - Driving antiskid adjustment and control method for motor-driven vehicle

Info

Publication number: CN102267459B
Application number: CN2011101270485A
Authority: CN
Inventors: 张俊智; 孔德聪; 吕辰
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2011-05-17
Filing date: 2011-05-17
Publication date: 2013-07-10
Anticipated expiration: 2031-05-17
Also published as: CN102267459A

Abstract

The invention relates to a driving anti-skid adjustment control method of a motor-driven vehicle, comprising the steps of: 1) setting a motor-driven vehicle anti-skid adjustment control system including a drive motor, a wheel speed sensor, a drive anti-skid controller and a motor controller; 1) wheel speed The sensor sends the collected non-driving wheel angular velocity to the driving anti-skid controller, and the vehicle speed calculation module obtains the driving speed of the motor-driven vehicle according to the non-driving wheel angular velocity; 2) The vehicle acceleration calculation module obtains the longitudinal acceleration according to the driving speed; 3) In addition The two wheel speed sensors send the collected drive wheel angular velocity to the slip rate calculation module in the drive anti-skid controller to obtain the longitudinal slip rate and longitudinal slip rate derivative of the drive wheel; 4) The target drive force calculation module uses the Speed, longitudinal acceleration and longitudinal slip rate of the drive wheel obtain the target drive torque at this time; 5) The motor controller obtains the motor torque command value according to the target drive torque to complete the drive anti-slip adjustment. The invention can be widely used in the anti-slip control of motor-driven vehicles.

Description

A driving anti-slip adjustment control method for a motor-driven vehicle

技术领域 technical field

本发明涉及一种电机驱动调节控制方法，特别是关于一种适用于纯电动、混合动力以及燃料电池电机驱动车辆的驱动防滑调节控制方法。The invention relates to a motor drive regulation control method, in particular to a drive anti-slip regulation control method suitable for pure electric, hybrid and fuel cell motor driven vehicles.

背景技术 Background technique

一般纯电动车辆、混合动力车辆以及燃料电池车辆采用电机进行驱动，与内燃机驱动的方式相比，电机驱动具有以下特点：1、电机力矩可以通过电流、电压信号较为准确的获得；2、现代电机控制技术可以准确控制电机的力矩；3、电机力矩响应比内燃机力矩响应迅速。目前电机驱动车辆都安装了驱动防滑系统，防止电机驱动车辆在驱动时出现车轮滑转的情况，从而避免电机驱动车辆丧失附着能力，出现侧滑或丧失转向能力等危险状况，同时保证了电机驱动车辆的加速性能。Generally, pure electric vehicles, hybrid vehicles and fuel cell vehicles are driven by motors. Compared with internal combustion engine drive, motor drive has the following characteristics: 1. Motor torque can be obtained more accurately through current and voltage signals; 2. Modern motors The control technology can accurately control the torque of the motor; 3. The torque response of the motor is faster than that of the internal combustion engine. At present, motor-driven vehicles are equipped with drive anti-skid systems to prevent motor-driven vehicles from slipping when they are driving, thereby avoiding motor-driven vehicles from losing adhesion, slipping or losing steering ability and other dangerous situations, and at the same time ensuring motor drive. Acceleration performance of the vehicle.

目前，电机驱动车辆的驱动防滑系统一般采用传统逻辑门限值控制方法，传统逻辑门限值控制方法是通过对电机驱动车辆驱动轮的角加速度和纵向滑移率进行检测，对驱动轮进行制动，同时对电机输出扭矩进行粗略调节。传统逻辑门限值控制方法由于对制动力和驱动力进行粗略调节，使得驱动轮的纵向滑移率波动较大，无法稳定在理想滑移率附近，控制效果受到制约。At present, the driving anti-skid system of motor-driven vehicles generally adopts the traditional logic threshold value control method. At the same time, roughly adjust the output torque of the motor. Due to the rough adjustment of the braking force and driving force in the traditional logic threshold control method, the longitudinal slip rate of the driving wheel fluctuates greatly, which cannot be stabilized near the ideal slip rate, and the control effect is restricted.

对现有的各类电机驱动车辆而言，大多数驱动防滑系统沿用了传统逻辑门限值控制方法，没有充分利用电机转矩获取方便、控制精准、响应迅速的特点，因此电机驱动车辆的驱动防滑效果尚有较大的改善空间。For the existing types of motor-driven vehicles, most of the drive anti-skid systems follow the traditional logic threshold value control method, which does not make full use of the characteristics of convenient acquisition of motor torque, precise control, and rapid response. Therefore, the drive of motor-driven vehicles There is still a lot of room for improvement in the anti-skid effect.

发明内容 Contents of the invention

针对上述问题，本发明的目的是提供一种驱动防滑效果较好，具有较强可操纵性和较高实用价值的适用于电机驱动车辆的驱动防滑调节控制方法。In view of the above problems, the purpose of the present invention is to provide a driving anti-skid adjustment control method suitable for motor-driven vehicles with better driving anti-skid effect, strong maneuverability and high practical value.

为实现上述目的，本发明采取以下技术方案：一种电机驱动车辆的驱动防滑调节控制方法，包括如下步骤：1)设置一包括两个驱动电机、四个轮速传感器、一个驱动防滑控制器和一个电机控制器的电机驱动防滑调节控制系统，所述驱动防滑控制器包括车速计算模块、车辆加速度计算模块、滑移率计算模块和目标驱动力矩计算模块；2)两个轮速传感器将采集到的非驱动轮角速度ω′发送至所述驱动防滑控制器，由所述车速计算模块根据非驱动轮角速度ω′得到电机驱动车辆的行驶速度V；3)由所述车辆加速度计算模块得到电机驱动车辆的纵向加速度

4)另外两个轮速传感器将采集到的驱动轮角速度ω发送至所述驱动防滑控制器，由所述滑移率计算模块利用驱动轮角速度ω和电机驱动车辆的行驶速度V得到驱动轮的纵向滑移率S和纵向滑移率导数5)根据所述步骤2)～4)，所述目标驱动力计算模块利用电机驱动车辆的行驶速度V、电机驱动车辆的纵向加速度

和驱动轮纵向滑移率S得到此时的目标驱动力矩T_d；6)电机控制器根据目标驱动力矩T_d得到电机力矩命令值T_m＝i_gi₀T_d，对电机力矩进行动态控制，完成驱动防滑调节；式中，i_g为电机控制器的变速器传动比，i₀为电机控制器的主减速器传动比。In order to achieve the above object, the present invention adopts the following technical proposals: a driving anti-skid adjustment control method of a motor-driven vehicle, comprising the following steps: 1) setting one including two driving motors, four wheel speed sensors, a driving anti-skid controller and A motor-driven anti-skid adjustment control system of a motor controller, the drive anti-skid controller includes a vehicle speed calculation module, a vehicle acceleration calculation module, a slip ratio calculation module and a target drive torque calculation module; 2) two wheel speed sensors will collect The non-driving wheel angular velocity ω' is sent to the driving anti-skid controller, and the vehicle speed calculation module obtains the driving speed V of the motor-driven vehicle according to the non-driving wheel angular velocity ω'; 3) the vehicle acceleration calculation module obtains the motor-driven longitudinal acceleration of the vehicle

4) The other two wheel speed sensors send the collected driving wheel angular velocity ω to the driving anti-skid controller, and the slip rate calculation module uses the driving wheel angular velocity ω and the driving speed V of the motor-driven vehicle to obtain the driving wheel angular velocity ω. Longitudinal slip rate S and longitudinal slip rate derivative 5) According to the steps 2) to 4), the target driving force calculation module uses the driving speed V of the motor-driven vehicle, the longitudinal acceleration of the motor-driven vehicle

and the longitudinal slip rate S of the driving wheel to obtain the target driving torque T _d at this time; 6) The motor controller obtains the motor torque command value T _m = i _g i ₀ T _d according to the target driving torque T _d , and dynamically controls the motor torque , to complete the drive anti-slip adjustment; where, i _g is the transmission ratio of the motor controller, and i ₀ is the transmission ratio of the final drive of the motor controller.

所述步骤4)中，所述驱动轮的纵向滑移率S与其纵向滑移率导数

满足如下关系式：In the step 4), the longitudinal slip rate S of the drive wheel and its longitudinal slip rate derivative

Satisfy the following relationship:

$\overset{. .}{S S} = = k k ((S S - - {S S}^{* *})),,$

式中，k是常数，S^*是理想滑移率。where k is a constant and S ^* is the ideal slip ratio.

所述步骤5)中，所述目标驱动力矩T_d为：In the step 5), the target driving torque T _d is:

${T T}_{d d} = = \frac{VI VI}{r r {((11 - - S S))}^{22}} {{\frac{{S S}^{* *} - - S S}{k k} + + \frac{11}{V V} [[\overset{. .}{V V} ((11 - - S S)) + + \frac{{r r}^{22} \overset{. .}{V V} {m m}_{t t}}{I I} {((11 - - S S))}^{22}]]}},,$

其中，I是车轮的转动惯量，S^*是理想滑移率，r是车轮的有效滚动半径，m_t为二分之一电机驱动车辆的质量，k是常数，V是电机驱动车辆的行驶速度，是电机驱动车辆的纵向加速度，S是驱动轮纵向滑移率。where I is the moment of inertia of the wheel, S ^* is the ideal slip ratio, r is the effective rolling radius of the wheel, m _t is one-half the mass of the motor-driven vehicle, k is a constant, and V is the driving speed of the motor-driven vehicle , is the longitudinal acceleration of the motor-driven vehicle, and S is the longitudinal slip rate of the driving wheel.

本发明由于采取以上技术方案，其具有以下优点：1、本发明对电机驱动车辆驱动轮的纵向滑移率导数进行控制，能够维持电机驱动车辆驱动轮纵向滑移率稳定在理想值，很好的改善驱动防滑效果。2、本发明能够充分利用电机驱动力矩响应迅速、准确的优点，兼顾了驱动的安全性、动力性和舒适性。3、本发明的电机驱动防滑调节控制系统结构简单，成本较低，具有较强的可操纵性和较高的实用价值。因此，本发明能广泛应用于电机驱动车辆的防滑控制中。Due to the adoption of the above technical scheme, the present invention has the following advantages: 1. The present invention controls the longitudinal slip rate derivative of the drive wheel of the motor-driven vehicle, and can maintain the longitudinal slip rate of the drive wheel of the motor-driven vehicle stable at an ideal value, which is very good Improved drive anti-slip effect. 2. The present invention can make full use of the advantages of rapid and accurate motor driving torque response, taking into account the driving safety, power and comfort. 3. The motor-driven anti-skid adjustment control system of the present invention has simple structure, low cost, strong maneuverability and high practical value. Therefore, the present invention can be widely used in anti-slip control of motor-driven vehicles.

附图说明 Description of drawings

图1是本发明电机驱动防滑调节控制系统的结构示意图Fig. 1 is the structural representation of motor-driven anti-slip adjustment control system of the present invention

图2是本发明驱动防滑控制器的结构框图Fig. 2 is the structural block diagram of driving anti-slip controller of the present invention

图3是本发明电机驱动车辆的车轮动力学模型示意图Fig. 3 is a schematic diagram of the wheel dynamics model of the motor-driven vehicle of the present invention

图4是本发明电机驱动防滑调节控制的流程示意图Fig. 4 is a schematic flow chart of motor-driven anti-slip adjustment control of the present invention

具体实施方式 Detailed ways

下面结合附图和实施例对本发明进行详细的描述。The present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

如图1、图2所示，本发明的电机驱动防滑调节控制系统包括两个驱动电机1、四个轮速传感器2、一个驱动防滑控制器3和一个电机控制器4，其中，驱动防滑控制器3包括车速计算模块31、车辆加速度计算模块32、滑移率计算模块33和目标驱动力矩计算模块34。两个驱动电机1分别对电机驱动车辆的两个驱动轮5施加力矩，为电机驱动车辆提供驱动力。四个轮速传感器2分别安装在电机驱动车辆的两个驱动轮5和两个非驱动轮6上，并将采集得到的各驱动轮5和各非驱动轮6的车轮角速度信号发送至驱动防滑控制器3内进行处理，得到目标驱动力矩。驱动防滑控制器3再把目标驱动力矩发送至电机控制器4，由电机控制器4调节控制两驱动电机1的力矩，进而完成对电机驱动车辆电机的驱动防滑调节控制。As shown in Figures 1 and 2, the motor-driven anti-skid adjustment control system of the present invention includes two drive motors 1, four wheel speed sensors 2, a drive anti-skid controller 3 and a motor controller 4, wherein the drive anti-skid control The controller 3 includes a vehicle speed calculation module 31 , a vehicle acceleration calculation module 32 , a slip ratio calculation module 33 and a target drive torque calculation module 34 . The two driving motors 1 respectively apply torque to the two driving wheels 5 of the motor-driven vehicle to provide driving force for the motor-driven vehicle. Four wheel speed sensors 2 are respectively installed on the two driving wheels 5 and two non-driving wheels 6 of the motor-driven vehicle, and the wheel angular velocity signals of each driving wheel 5 and each non-driving wheel 6 collected are sent to the driving anti-skid Process in the controller 3 to obtain the target drive torque. The drive anti-skid controller 3 then sends the target drive torque to the motor controller 4, and the motor controller 4 adjusts and controls the torque of the two driving motors 1, thereby completing the anti-skid adjustment control of the motor-driven vehicle motor.

如图3所示，电机驱动车辆的每个车轮均具有两个自由度，分别是电机驱动车辆的行驶速度V和电机驱动车辆的车轮角速度。电机驱动车辆的车轮分为驱动轮5和非驱动轮6，所以电机驱动车辆的车轮角速度又分为驱动轮角速度ω和非驱动轮角速度ω′，由于非驱动轮6与地面之间不存在滑转，因此利用非驱动轮角速度ω′计算出电机驱动车辆的行驶速度V，电机驱动车辆的行驶速度V的计算公式如下；As shown in Figure 3, each wheel of a motor-driven vehicle has two degrees of freedom, which are the driving speed V of the motor-driven vehicle and the wheel angular velocity of the motor-driven vehicle. The wheels of motor-driven vehicles are divided into driving wheels 5 and non-driving wheels 6, so the wheel angular velocity of motor-driven vehicles is further divided into driving wheel angular velocity ω and non-driving wheel angular velocity ω′, since there is no slip between non-driving wheels 6 and the ground Therefore, the driving speed V of the motor-driven vehicle is calculated by using the non-driving wheel angular velocity ω′, and the calculation formula of the driving speed V of the motor-driven vehicle is as follows;

V＝rω′， (1)V=rω′, (1)

式中，r为车轮的有效滚动半径。In the formula, r is the effective rolling radius of the wheel.

根据动力学关系得到电机驱动车辆的纵向加速度

各驱动轮5的角加速度

和各驱动轮5的纵向滑移率S分别为：Obtain the longitudinal acceleration of the motor-driven vehicle according to the dynamic relationship

Angular acceleration of each driving wheel 5

and the longitudinal slip rate S of each driving wheel 5 are respectively:

$\overset{. .}{V V} = = \frac{{F f}_{x x}}{{m m}_{t t}},, - - - - - - ((22))$

$\overset{. .}{ω ω} = = \frac{11}{I I} (({T T}_{d d} - - r r {F f}_{x x})),, - - - - - - ((33))$

$S S = = \frac{V V - - rω rω}{V V},, - - - - - - ((44))$

上述式(2)中，m_t为二分之一电机驱动车辆的质量，电机驱动车辆的质量是由整个电机驱动车辆的簧上质量m_vs、两个驱动轮质量m_w和两个非驱动轮质量m′_w叠加得到，即

Fx是电机驱动车辆的车轮与路面之间的纵向附着力；式(3)中，I是车轮的转动惯量；T_d是目标驱动力矩，对于电机驱动车辆来说，电机可以对车轮进行制动，因此目标驱动力矩T_d可以是负值。In the above formula (2), m _t is one half of the mass of the motor-driven vehicle, and the mass of the motor-driven vehicle is the sprung mass m _vs of the entire motor-driven vehicle, the mass of two driving wheels m _w and the two non-driving The wheel mass m′ _w is superimposed to get, that is,

Fx is the longitudinal adhesion between the wheel of the motor-driven vehicle and the road surface; in formula (3), I is the moment of inertia of the wheel; T _d is the target driving torque, for the motor-driven vehicle, the motor can brake the wheel , so the target driving torque T _d can be a negative value.

如图4所示，根据电机驱动车辆防滑调节控制系统，本发明的电机驱动车辆防滑调节控制方法包括如下步骤：As shown in Figure 4, according to the motor-driven vehicle anti-skid adjustment control system, the motor-driven vehicle anti-skid adjustment control method of the present invention includes the following steps:

1)两个轮速传感器2将采集到的非驱动轮角速度ω′发送至驱动防滑控制器3，驱动防滑控制器3中的车速计算模块31根据非驱动轮角速度ω′得到电机驱动车辆的行驶速度V。1) Two wheel speed sensors 2 send the collected non-driving wheel angular velocity ω' to the driving anti-skid controller 3, and the vehicle speed calculation module 31 in the driving anti-skid controller 3 obtains the driving speed of the motor-driven vehicle according to the non-driving wheel angular velocity ω' speed v.

2)由驱动防滑控制器3的车辆加速度计算模块32得到电机驱动车辆的纵向加速度

2) Obtain the longitudinal acceleration of the motor-driven vehicle by the vehicle acceleration calculation module 32 of the drive anti-skid controller 3

3)另外两个轮速传感器2将采集到的驱动轮角速度ω发送至驱动防滑控制器3，驱动防滑控制器3的滑移率计算模块33利用驱动轮角速度ω和电机驱动车辆的行驶速度V得到驱动轮5的纵向滑移率S和纵向滑移率导数

3) The other two wheel speed sensors 2 send the collected driving wheel angular velocity ω to the driving anti-skid controller 3, and the slip rate calculation module 33 of the driving anti-skid controller 3 uses the driving wheel angular velocity ω and the driving speed V of the motor-driven vehicle Obtain the longitudinal slip rate S and the longitudinal slip rate derivative of the driving wheel 5

为了确保驱动轮5的纵向滑移率S稳定在理想滑移率S^*附近，驱动轮5的纵向滑移率S及纵向滑移率导数

要满足

其中k是常数；当电机驱动车辆驱动轮5的纵向滑移率S和驱动轮5的纵向滑移率导数满足关系式时，驱动轮5的纵向滑移率S将快速趋近于理想滑移率S^*，最终稳定在理想滑移率S^*处，从而保证电机驱动车辆充分利用地面附着进行驱动，避免驱动轮滑转；In order to ensure that the longitudinal slip rate S of the drive wheel 5 is stable near the ideal slip rate S ^* , the longitudinal slip rate S and the derivative of the longitudinal slip rate of the drive wheel 5

to be satisfied

Wherein k is a constant; when the motor drives the longitudinal slip rate S of the vehicle drive wheel 5 and the longitudinal slip rate derivative of the drive wheel 5 satisfy When the relationship is expressed, the longitudinal slip rate S of the driving wheel 5 will quickly approach the ideal slip rate S ^* , and finally stabilize at the ideal slip rate S ^* , so as to ensure that the motor-driven vehicle can make full use of the ground adhesion to drive and avoid driving wheel slip;

由上述公式(4)可知，驱动轮5的纵向滑移率导数为：As can be seen from the above formula (4), the longitudinal slip rate derivative of the drive wheel 5 for:

$\overset{. .}{S S} = = \frac{\overset{. .}{V V} ((11 - - S S)) - - r r \overset{. .}{ω ω}}{V V},, - - - - - - ((55))$

将上述公式(2)和公式(3)代入上述公式(5)中，得到驱动轮5的纵向滑移率导数

的另一种表达形式：Substituting the above formula (2) and formula (3) into the above formula (5), the longitudinal slip rate derivative of the driving wheel 5 is obtained

Another form of expression:

$\overset{. .}{S S} = = - - \frac{11}{V V} [[\overset{. .}{V V} ((11 - - S S)) + + \frac{{r r}^{22} \overset{. .}{V V} {m m}_{t t}}{I I} {((11 - - S S))}^{22}]] + + ((\frac{r r}{VI VI})) {((11 - - S S))}^{22} {T T}_{d d} . . - - - - - - ((66))$

4)根据步骤1)～3)，驱动防滑控制器3的目标驱动力矩计算模块34利用电机驱动车辆的行驶速度V、电机驱动车辆的纵向加速度

和驱动轮纵向滑移率S得到此时的目标驱动力矩T_d；4) According to steps 1) to 3), the target drive torque calculation module 34 of the drive anti-skid controller 3 uses the travel speed V of the motor-driven vehicle, the longitudinal acceleration of the motor-driven vehicle

and the longitudinal slip rate S of the drive wheel to obtain the target drive torque T _d at this time;

结合公式(6)及纵向滑移率S与纵向滑移率导数

的关系式可以计算得到目标驱动力矩T_d的表达式如下：Combined with formula (6) and longitudinal slip rate S and longitudinal slip rate derivative

The relational expression of can be calculated to obtain the expression of the target driving torque T _d as follows:

${T T}_{d d} = = \frac{VI VI}{r r {((11 - - S S))}^{22}} {{\frac{{S S}^{* *} - - S S}{k k} + + \frac{11}{V V} [[\overset{. .}{V V} ((11 - - S S)) + + \frac{{r r}^{22} \overset{. .}{V V} {m m}_{t t}}{I I} {((11 - - S S))}^{22}]]}} . . - - - - - - ((77))$

5)电机控制器4根据步骤4)中的目标驱动力矩T_d得到电机力矩命令值T_m，对电机力矩进行动态控制，完成驱动防滑调节，改善了驱动防滑效果；其中，电机力矩命令值T_m为：5) The motor controller 4 obtains the motor torque command value T _m according to the target drive torque T _d in step 4), dynamically controls the motor torque, completes the drive anti-skid adjustment, and improves the drive anti-skid effect; wherein, the motor torque command value T _m is:

T_m＝i_gi₀T_d， (8)T _m = i _g i ₀ T _d , (8)

式中，i_g为电机控制器4的变速器传动比，i₀为电机控制器4的主减速器传动比。In the formula, i _g is the gear ratio of the transmission of the motor controller 4, and i ₀ is the gear ratio of the main reducer of the motor controller 4.

上述各实施例仅用于说明本发明，其中各部件的结构和连接方式等都是可以有所变化的，凡是在本发明技术方案的基础上进行的等同变换和改进，均不应排除在本发明的保护范围之外。Above-mentioned each embodiment is only for illustrating the present invention, and wherein the structure of each component and connection mode etc. all can be changed to some extent, and all equivalent transformations and improvements carried out on the basis of the technical solution of the present invention should not be excluded from the present invention. outside the scope of protection of the invention.

Claims

1. the driving anti-slip regulation control method of a motor-driven vehicle comprises the steps:

1) arrange one and comprise two drive motor, four wheel speed sensors, a motor-driven anti-slip regulation control system that drives anti-skid controller and an electric machine controller, described driving anti-skid controller comprises speed of a motor vehicle computing module, vehicle acceleration computing module, slip rate computing module and target drives moment computing module;

2) two wheel speed sensors are the described driving anti-skid controller of the non-driving wheel angular velocity omega that collects ' be sent to, by described speed of a motor vehicle computing module according to non-driving wheel angular velocity omega ' the obtain moving velocity V of motor-driven vehicle;

3) obtained the longitudinal acceleration of motor-driven vehicle by described vehicle acceleration computing module

4) two other wheel speed sensors is sent to described driving anti-skid controller with the drive wheel angular velocity omega that collects, and utilizes the moving velocity V of drive wheel angular velocity omega and motor-driven vehicle to obtain straight skidding rate S and the straight skidding rate derivative of drive wheel by described slip rate computing module

The straight skidding rate S of described drive wheel and its straight skidding rate derivative

Satisfy following relational expression:

\overset{\cdot}{S} = k (S - S^{*}),

In the formula, k is constant, S ^*It is the desired slip rate;

5) according to described step 2)～4), described target drive force computing module utilizes the moving velocity V of motor-driven vehicle, the longitudinal acceleration of motor-driven vehicle

Obtain target drives moment T at this moment with drive wheel straight skidding rate S _dDescribed target drives moment T _dFor:

T_{d} = \frac{VI}{r {(1 - S)}^{2}} {\frac{S^{*} - S}{k} + \frac{1}{V} [\overset{\cdot}{V} (1 - S) + \frac{r^{2} {\overset{\cdot}{V} m}_{t}}{I} {(1 - S)}^{2}]},

Wherein, I is the rotor inertia of wheel, S ^*Be the desired slip rate, r is the effective rolling radius of wheel, m _tBe the quality of 1/2nd motor-driven vehicles, k is constant, and V is the moving velocity of motor-driven vehicle,

Be the longitudinal acceleration of motor-driven vehicle, S is drive wheel straight skidding rate;

6) electric machine controller is according to target drives moment T _dObtain motor torque bid value T _m=i _gi ₀T _d, motor torque is dynamically controlled, finish the driving anti-slip regulation; In the formula, i _gBe the transmission ratio of electric machine controller, i ₀Main reduction gear transmitting ratio for electric machine controller.