Control method of p-eps power assist current

Abstract

The invention discloses a control method of P-EPS boosting current. The method comprises: setting torque reference value, and when detecting the input torque of a P-EPS is greater than the torque reference value, controlling the boosting current of the motor to decrease. According to the control method of the P-EPS boosting current, the boosting current is decreased when the input torque is too large by setting the torque reference value, so as to limit the current ahead of time, and thus the P-EPS dead center is protected, the motor is prevented from being in the maximum current working statefor a long time, frequent overtemperature caused by long time and large current working is prevented, and the motor is effectively protected; and the control method of the P-EPS boosting current alsoplays a role of protecting the dead center, and plays a role of protecting a rack of the P-EPS to some extent.

Description

technical field [0001] The invention belongs to the technical field of vehicle steering systems, and in particular, the invention relates to a control method of a P-EPS assist current. Background technique [0002] Electric Power Steering (EPS) technology is a new technology in the field of automobile steering in the past ten years, and has achieved considerable development abroad. EPS is also a research hotspot in the domestic steering industry. As a safety part of the car, the performance of EPS is directly related to the safety and reliability of the car, and the lightness and sensitivity of the driver. Electric power steering system is further divided into column type electric power steering system (C-EPS for short), pinion type electric power steering system (P-EPS for short) and rack type electric power steering system (R-EPS for short). [0003] For P-EPS, during the steering process of the car, the driver turns the steering wheel to give the EPS an input torque, and...

AI Technical Summary

Problems solved by technology

[0006] 1. If the motor is in the working state of maximum current for a long time, the temperature of the MOS tube in the motor and ECU will rise rapidly, which may cause the motor and MOS tube to burn out and stop the EPS;

[0007] 2. When the motor is in the working state of maximum current, the internal rack of P-EPS is close to the limit position at this time, and the input torque continues to increase, so that the motor is in the working state of maximum current for a long time, which may make the rack reach or even exceed limit position, thereby damaging parts

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