Study On Three-Phase PMSM Used In Direct Drive Washing Machine

Currently，driving motors of washing machine include single-phase induction motor,universal motor, switched reluctance motor and variable-frequency induction motor.Because efficiency of driving motors is low, with the transmission system, efficiency ofentire driving system of washing machine is low.To overcome weaknesses of traditional transmission system, a kind of direct drivemotor is designed to increase efficiency of washing machine. In this paper, according to thelow efficiency problem of traditional washing machine. A kind of three-phase PMSM usedin direct drive washing machine is designed to replace the traditional washing machinedriving system. PMSM has high efficiency, high torque density, low cogging torque, andability of increasing speed by weaken the field, which meets the requirement of washingmachine. Stator of prototype is traditional induction motor’s stator, non-uniform air gapstructure, and single-layer chain winding are used. Hollow shafting is used to connectbetween the washing machine and motor, it can make washing machine operate stably. Inthe same structure of non-uniform air gap structure of rotor，comparing cogging torque andD-axis and Q-axis reactance under the radial segmented structure,“V” segmented structureand tangential embedded structure.Besides, analysis iron loss of stator and eddy currentloss of permanent magnet. Analyze the distribution of iron loss of stator and current loss ofpermanent magnet. Sensorless control method such as VVVF and SMO methods are usedto control PMSM used in direct drive washing machine. Simulation results are proved thatcontrol methods are reasonable.Choose single-phase to three-phase converter to drive the PMSM., control methods ofconverter can meet the requirements of washing machine. It is proved that PMSM used indirect drive washing machine can save much energy in experiment.