Research on Low Frequency Torque Ripple of In-wheel Motor of Four Wheel Independent Drive

摘要

In-wheel motor is a key power element for four wheel independent drive electric vehicle. It can supply accurate driving force control and achieve energy saving in electric power vehicle. Switched Reluctance (SR) motor has become an ideal candidate due to high output torque and reliable performance. However, huge output torque ripple in operation, which affects the comfort and handling stability of electric vehicle, limits its application in vehicle. In this paper, some factors behind low frequency noise and torque ripple of SR motor are investigated from a view of energy consumption including magnetic flux path pattern in SR motor and current imbalance. Furthermore, phase current balance control strategies to improve output torque ripple in operation are proposed. Results show that low frequency noise and torque ripple can be eliminated by applying the proposed current balance control strategy. It provides a good design method for SR motor to achieve excellent comfort and handling performance in four wheel independent drive vehicle.