Research On Torque And Angle Sensor For Electric Power Steeirng System

The torque and angle sensor is one of the key parts of an electric powersteering(EPS) system, and the characteristic of EPS system is much concerned with theoutput of the torque and angle sensor. In order to meet the needs of electric powersteering system for torque and angle measurement requirements, this thesis designed anew intelligent sensor that measure torque and angle signal without contact.At first, the principle and feature of various EPS sensors were analyzed, especiallythe sensor that could measure the torque and steering angle at the same time. After that,it introduced the basic theory of giant magneto resistance, and summarized theconventional torque measuring methods. According to the vehicle steeringcharacteristics and GMR chip performance, this thesis presented a new measuringmethod that can measure the angle and toque at the same time. Through analyzing theangle and torque measurement for gear transmission, it determined the gear basicparameter requirements.Secondly, in this thesis, the drive gear, a torsion bar and several other key parts ofthe sensor were detailed designed. In this thesis, the measuring circuit included: anglesensor circuit chip module, power supplying management module, JTAG module, andCAN communication module.It designed each measurement circuit.At last, calibration test device was designed, and sensor calibration tests werecarried out. It had been found that the sensor has excellent output characteristic, andcould satisfy the requirement of performance for EPS torque and angle sensor.