Pulse torque method of permanent-magnet synchronous motor for lowering electric power steering

Abstract

The invention discloses a pulse torque method of a permanent-magnet synchronous motor for lowering electric power steering. The method comprises the following steps of a, obtaining a tooth groove rotary angle according to an electric rotor angle, and estimating tooth groove torque of the permanent-magnet synchronous motor; b, obtaining a flux harmonic rotary angle according to the electric rotor angle, and estimating flux harmonic torque of the permanent-magnet synchronous motor; c, weakening periodic pulse torque caused by a tooth groove and flux harmonic waves through an iterative control algorithm. Through the iterative learning control algorithm, the periodic pulse torque caused by the tooth groove and the flux harmonic waves is weakened, and the precision of motor controlling is improved, so that an EPS system obtains a better steering hand feeling.

Description

technical field [0001] The invention relates to an automobile electronic technology, in particular to an electronic technology in an electric power steering system of an automobile, which is used for reducing the pulsating torque of a permanent magnet synchronous motor. Background technique [0002] The electric power steering system is composed of a steering column, a reduction mechanism, a rack and pinion, a power assist motor, a sensor, and an ECU control unit. The torque sensor is connected in the middle of the steering shaft through a torsion bar. When the car is turning, the torque sensor starts to work and converts the relative rotation angle into torque electrical signals. These electrical signals are sent to the electronic control unit ECU through the data bus, that is, the torque applied by the driver on the steering wheel. The electronic control unit ECU according to The rotation torque of the steering wheel and the vehicle speed and other data signals send actio...

AI Technical Summary

Problems solved by technology

[0004] In terms of body design, the schematic diagram of the cogging torque waveform is as follows figure 1 As shown, there are many ways to weaken the cogging torque and flux harmonic torque, but it is impossible to completely eliminate the pulsating torque generated by the motor body due to the manufacturing process of the motor.

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