New energy vehicle and its motor torque determination method, device and motor

Abstract

A new energy vehicle and its motor torque determination method, device, and motor, the method comprising the following steps: obtaining the motor speed of the motor, the motor speed having a direction and value; using hysteresis control to correct the motor speed direction; determine the direction of the motor torque according to the direction of the motor power of the motor and the direction of the motor speed; determine the value of the motor torque according to the value of the motor power and the value of the motor speed. The solution of the present invention can correct the direction of the motor speed to avoid frequent changes in the direction of the motor torque when the motor speed fluctuates near zero, thereby more properly determining the direction of the motor torque and ensuring driving safety while protecting the motor .

Description

technical field [0001] The invention relates to the field of power systems of new energy vehicles, in particular to a new energy vehicle and its motor torque determination method, device and motor. Background technique [0002] At present, new energy vehicles including pure electric vehicles and hybrid vehicles have received widespread attention. In specific applications, it is necessary to properly determine the motor torque so that the vehicle can output torque within a suitable range of motor torque according to actual needs. [0003] In the prior art, the motor torque can be obtained according to the motor power and the motor speed of the motor, for example, through the following calculation formula: [0004] T=9550*P / N; [0005] Wherein, T is used to represent the motor torque in Newton-meter (NM); specifically, as a vector, the motor torque includes the value of the motor torque and the direction of the motor torque. [0006] P is used to represent the motor power, ...

AI Technical Summary

Problems solved by technology

[0008] However, when the motor speed fluctuates around zero, the direction of the motor speed will change between positive and negative with the fluctuation, the direction of the motor torque will change with the direction of the motor speed, and the frequent changes in the direction of the motor torque Not only will it damage the motor, but it will also cause driving hazards in severe cases

Taking the vehicle in the driving state as an example, when the direction of the motor power is positive, if the motor speed drops to zero during the climbing process of the vehicle, due to the inertia and gravity, the wheels may reverse slightly, causing the direction of the motor speed to be reversed. If it becomes negative, according to the corresponding relationship between the motor power, motor speed and motor torque, the direction of the motor torque will then become negative, so that the reverse torque output will cause the vehicle to slip backwards, causing the risk of rear-end collision

If during the process of reversing the vehicle, due to inertia or gravity, the wheels may rotate slightly forward and forward, causing the direction of motor speed to become positive, and the direction of motor torque will then become positive, thereby outputting forward torque Causes the vehicle to rush forward, causing a collision hazard

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