EPS control method for improving hand touch of steering wheel rapidly manipulated by driver

Abstract

The invention discloses an EPS control method for improving hand touch of a steering wheel rapidly manipulated by a driver. The method comprises the following steps: in step S1, a three phase current of a permanent magnet synchronous motor is obtained, the collected three phase current is subjected to Clarke conversion and Park conversion, and therefore an actual field current instruction id and an actual torque current instruction iq are obtained; in step S2, a steering wheel torque signal, a vehicle speed signal and steering wheel angular velocity omega are obtained in real time; in step S3, electric motor stator voltage us is detected and is compared with a maximum voltage Umax which can be provided by an inverter; in step S4, when us is less than Umax, an EPS system enters a torque loop to execute id=0 control; in step S5, when us is greater than Umax, the EPS system enters a rotating speed loop to execute advance angle magnetic-field-weakening control. According to the EPS control method, overall consideration is given to specific requirements of EPS system time sharing for torque and rotating speed, and a problem that the steering wheel is difficult to manipulate in an EPS system due to heavy weight is well addressed.

Description

technical field [0001] The invention relates to the technical field of automobiles, in particular to an EPS control method for improving the driver's fast steering wheel feel. Background technique [0002] Electric power steering system (electric power steering system, EPS), because of its compact structure, energy saving and environmental protection, and can also match different programs according to different models, greatly shortening the development cycle, so EPS has basically been popularized in passenger cars in the market . In recent years, with the rapid development of power electronics technology, new motor control theory and rare earth permanent magnet materials, permanent magnet synchronous motors (permanent magnet synchronous motor, PMSM) have been rapidly popularized and applied. Compared with the traditional electric excitation synchronous motor, the permanent magnet synchronous motor, especially the rare earth permanent magnet synchronous motor has the advant...

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Problems solved by technology

[0003] However, the permanent magnet synchronous motor is different from the separately excited motor, which can adjust the excitation current to expand the speed, which greatly limits the speed regulation range of the permanent magnet synchronous motor. Although this can meet the requirements of the EPS system for the motor speed under normal working conditions, However, under special working conditions, such as emergency obstacle avoidance, the driver needs to quickly manipulate the steering wheel to avoid obstacles, which requires the permanent magnet synchronous motor to provide an instantaneous high speed, otherwise it will cause heavy steering of the steering wheel

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