Inertia Compensation Method and Related Devices for Electric Power Steering System

Abstract

The inertia compensation method and related devices of the electric power steering system provided by the present invention directly take the steering wheel torque as input, and calculate the second component of the inertia compensation torque based on the steering wheel torque, which belongs to feed-forward compensation; calculate the inertia compensation torque according to the motor speed and vehicle speed The first component belongs to feedback compensation. From the perspective of the force transmission path, the change of the driver's hand force leads to the change of the angular acceleration of the steering wheel shaft, which in turn causes the change of the angular velocity, and finally leads to the change of the rotation angle; it can be seen that there is an obvious time sequence from the torque to the rotation angle. The present invention combines feedback compensation and feedforward compensation, thereby reducing the hysteresis of inertia compensation torque caused by sampling and calculation delays, enabling inertia compensation torque to truly exert its due compensation effect, and reducing the impact of rotational inertia on the system The influence of dynamic characteristics makes the steering response of the system more sensitive and precise, thus improving the driver's driving experience.

Description

technical field [0001] The invention relates to the technical field of vehicles, and more specifically, relates to an inertia compensation method and a related device of an electric power steering system. Background technique [0002] The electric power steering system is a power system that uses the output torque of the motor to assist the driver and perform steering operations. The power assist motor is one of the core components of the electric power steering system. The greater the load on the front axle of the vehicle, the greater the power assist torque required, that is, the greater the power demand for the assist motor, making the volume of the assist motor larger; and the larger the volume of the assist motor, the greater its moment of inertia will also increase. Due to the existence of the deceleration mechanism, the influence of the moment of inertia of the booster motor on the system increases by the power of 2; this leads to a relatively large negative impact o...

AI Technical Summary

Problems solved by technology

This calculation process based on the feedback signal will cause a delay or lag of the signal, resulting in a delay or lag of the output inertia compensation torque

When this delay or lag exceeds a certain level, the inertia compensation function will lose its practical effect, not only cannot compensate the steering feel, but may even have a negative effect

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