Speed-regulating system for switched reluctance motor specially used for electric vehicle

Abstract

The invention relates to a speed-regulating system for a switched reluctance motor specially used for an electric vehicle and belongs to the field of a power control system of the electric vehicle. The speed-regulating system is characterized in that an output end of a controller is connected with a control end of a power converter; an input end of the controller is connected with an external preset; the output end of the power converter is connected with the motor while the input end is connected with a storage battery; the number of poles of a stator/rotor of SRM (Switched Reluctance Motor) is 24/16; an output shaft of the switched reluctance motor is connected with a load; a sensor comprises a current detector and a position detector; the position detector is arranged in the switched reluctance motor; the output ends of the current detector and the position detector are respectively connected with the input end of the controller; the integrated consistency of the existing SRD (Switched Reluctance Driver) is specifically improved; the load characteristic of vehicle working condition is met; the instantaneous power is high; the overload capacity is high; the accelerating property is excellent; the speed adjustable range is wide; the fluctuating problem of low-speed torque of the motor is solved; the noise of the SRM is reduced; the service life of the battery is prolonged; the electricity-saving effect is obvious; and the demand on the motor for the electric vehicle is met.

Description

technical field [0001] The invention provides a special switched reluctance motor speed control system for electric vehicles, which belongs to the field of power control systems of electric vehicles. Background technique [0002] There are three main types of AC motors commonly used in electric vehicles: asynchronous, permanent magnet, and switched reluctance. Among them, asynchronous motors are mainly used in pure electric vehicles (including cars and buses), and permanent magnet synchronous motors are mainly used in hybrid vehicles (including In passenger cars and passenger cars), switched reluctance motors are currently more used in passenger cars. In particular, due to the characteristics of high efficiency and high power density, permanent magnet synchronous motors are basically used in hybrid cars at present. [0003] Electric vehicles are divided into three types: pure electric, hybrid and fuel cell. Regardless of pure electric vehicles, hybrid electric vehicles or f...

AI Technical Summary

Problems solved by technology

[0005] 1) Brushed DC series motor: the advantages are large starting torque and strong overload capacity; the disadvantages are the need to change carbon brushes, high-speed ring fire, not suitable for high-speed operation, low efficiency, large size, poor protection ability, and poor energy feedback , mainly used in electric tricycles

[0006] 2) Brushed permanent magnet DC motor: the advantage is that it has higher efficiency than the brushed DC series motor, good energy feedback, average starting torque and overload capacity; the disadvantage is that it needs to replace the carbon brush, has ring fire at high speed, and is not suitable for high-speed operation. Moderate efficiency, large size, poor protection ability, mainly used on electric tricycles

[0007] 3) AC motor: the advantages are simple structure and high reliability of the motor itself; the disadvantage is that the starting torque is small, the starting current is large, and the motor needs to increase the starting current to generate large torque, but due to the limited characteristics of the battery, it is difficult for the battery to provide The large current affects the improvement of the motor torque. This kind of motor has low efficiency, complex control, and poor energy feedback performance.

[0008] 4) Permanent magnet synchronous motor: the advantage is that it has high efficiency and good energy feedback; the disadvantage is that the torque cannot be increased at low speed, and there is a problem of out of step, so it is rarely used

[0009] 5) Brushless DC motor: The advantages are: the motor has good external characteristics, the motor is small in size, light in weight, and has a wide speed range. The disadvantage is that the motor itself is more complicated than the AC motor, and the operating current is large, especially the motor magnetic steel is easy to demagnetize, which reduces the motor speed. and battery life

This control method is not suitable for electric vehicle control, and is not suitable for vehicle working conditions

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