Study On Non-Contact Position Sensor Based On Hall Effect And Application

As the feedback of automobile electronic control system, the performance of positionsensor directly affects the stability and reliability of the automobile control system.Because the automobile works in the heat, vibration and harsh environments for long term,the legacy contacting position sensor with potentiometer principle can easily lead toresistance wear out due to the friction between brush and resistance, and finally impactingits output characteristic and life time.With the development of sensing technology, it is the trend to replace thepotentiometer with non-contact sensor. In recent years, with the rapid developments of thehall technology, the immunity to electromagnetic interference and anti-drift capability ofhall sensor is greatly improved. Meanwhile, prices have gradually decreased. So positionsensor based on hall effect is replacing the potentiometer sensor step by step.This paper introduces the status of automobile position sensor and technologydevelopment firstly, all kinds of non-contact position sensor technology are reviewed,especially for three types of sensor, hall, inductive and magneto-resistive, which are mostlikely to be used in automobile position sensor the technical solutions, and hall sensor isfinally chosen after a technical tradeoff.A design method of automobile position sensor based on hall effect is concluded afterthe research of this subject. The feasibility, APQP, demonstration program as well as themagnetic circuit simulation, prototype manufacturing, calibration and test, non-standardequipment development and the software tools are all discussed in details. This methodplays a guiding significance for the design and development of hall position sensors.The magnetic circuit design of triaxis hall IC and flat linear hall IC could be simulatedanalyzed with COMSOL Multiphysics fintite element analysis software.In this thesis, a non-contact throttle position sensor is designed based on triaxishall-chip MLX90360, and a non-contact pedal position sensor is also designed based onlinear hall-chip TLE4997. The performance of both sensors meets the specifiedrequirements and suitable for mass production.