Design And Control System Research On Redundant Direct-drive In-wheel Motor

With the aggravation of global environmental pollution and resource problems,it is a kind of solution to replace the internal combustion engine with new energy vehicles.China is the largest automobile production and consumption country,so the research and industrial promotion of electric vehicle technology has become the focus of competition in the automotive industry.In this paper,a new type of multi-redundant direct-drive in-wheel permanent magnet brushless motor is designed based on sub motors.The paper designs a kind of direct-drive in-wheel PMSM with new structure based on sub motors.The stator of the motor is composed of four sets of three-phase windings with special winding arrangement.With the same motor,each of the stator part can be independently controlled.Therefore,there are four sub motors in the air gap.Two kinds of fault tolerant motor electromagnetic schemes are designed,which are suitable for high speed and low speed starting respectively.On the basis of this,a kind of hybrid fault tolerant motor,which is suitable for both the two modes,is designed by optimizing the parameters.Magnetic field distribution and steady state performance of the hybrid motor are studied based on Ansoft and Matlab.In addition,the simulation and experiments are carried out on a fault tolerant BLDCM prototype with four identical sub motors.The performance of the motor under normal operating conditions and several failure modes is simulated.A fault diagnosis and fault tolerant control scheme based on current compensation is proposed.The hardware platform of double closed loop control system based on dsPIC is established.The operating performance of the motor under normal conditions is measured,and the current detection and compensation function of the control system under the fault condition is also given.The experimental results show that the proposed multi redundant motor structure based on sub motor has good fault tolerance.