Steering wheel position detection circuit and steering wheel position detection method of EPS (Electric Power Steering) system

Abstract

The invention discloses a steering wheel position detection circuit of an EPS (Electric Power Steering) system. The steering wheel position detection circuit comprises a torque rotating angle sensor, a rotary transformer and an ECU (Electronic Control Unit), wherein the torque rotating angle sensor is used for obtaining an absolute rotating angle of a steering wheel; the rotary transformer is used for obtaining a rotating angle of a power-assisted motor; the ECU is used for collecting the output of the torque rotating angle sensor and calculating the absolute rotating angle of the steering wheel, and the ECU is also used for collecting the output of the rotary transformer and estimating the absolute rotating angle of the steering wheel. Once a calculating value of the absolute rotating angle of the steering wheel is not accordant with an estimated value, the ECU quits the calculating value, and just the estimated value is used as the absolute rotating angle of the steering wheel. According to the steering wheel position detection circuit disclosed by the invention, the problem that the calculated position of the steering wheel is inaccurate caused by signal burr of the torque rotating angle sensor or too-slow edge hopping can be solved.

Description

technical field [0001] The present application relates to an electric power steering system (Electric Power Steering, EPS system for short) of an automobile, in particular to a steering wheel position detection circuit therein. Background technique [0002] see figure 1 , which is the mechanical steering system on the car. It includes a steering wheel 11 , a steering column 12 , a steering gear 13 , a steering tie rod 14 and steering wheels 15 . The driver applies steering torque to the steering wheel 11, and the steering torque is input to the steering gear 13 through the steering column 12, and the amplified torque and decelerated motion of the steering gear 13 are transmitted to the steering rod 14, thereby driving the steering wheels 15 to move. [0003] see figure 2 , which is the electric power steering system on the car. On the basis of the mechanical steering system, it adds: [0004] ——The torque angle sensor 21 is used to detect the torque and the angle of ro...

AI Technical Summary

Problems solved by technology

[0027] The technical problem to be solved in this application is to provide a steering wheel position detection circuit of an electric power steering system, which can solve the problem of inaccurate calculation of the steering wheel position due to the glitch of the AS signal or the slow transition of the falling edge.

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