Three Phase PMSM And Its Control System Of Home Appliances

Household washing machines, air-conditioning compressor and other electrical appliances, generally use the single-phase power (220V,50Hz). At present, the single-phase asynchronous motor is driven by split-phase capacitor is mainly adopted. The efficiency of the transmission is only about 30%. In recent years, people have studied the single-phase permanent magnet motor which is also derived by split-phase capacitor, and it could increase the efficiency to 50%. The secondary winding of the single phase motor does not work when the motor running. Therefore, compared to the same power levels three-phase motor,the utilization of the motor materials is reduced at least 30% and the efficiency is also reduced at least 50%. With the development of the power electronics technology, the inverter washing machine and air-conditioning has a rapid development, but they still use the single-phase induction motor or single phase permanent magnet motor, and it only changing the frequency of the power supply, the higher efficiency is the result of the shift running.This inverter in this paper intends to use the single-phase power as input, and the output is symmetrical three-phase inverter.Three-phase low-voltage permanent magnet motor can make the transmission efficiency increased to 80% at least. The new control system of shifting speed which is based on the EMF automatic tracking control strategy is studied, and the open-loop frequency control of the without position sensor of the permanent magnet motor is realized. The control strategy of this system is introduced, at the same time the preliminary theoretical is also analyzed.Utilizing some general formula for the electromagnetic design of motor, the permanent magnet synchronous motor is designed combining with the motor design features of the household appliance. By using the Ansoft electromagnetic analysis software and the computational method of the field-circuit couple, the transient performance parameter of the motor is calculated. Finally, the electromagnetic design program is completed by constantly adjusting the value of the design. The single phase induction motor is rebuild according to the program. The correctness and feasibility of the procedure is proven, and it is also simple and convenient. This paper has important theoretical significance and great project worth to the improving design of the permanent magnet synchronous motor and its control system in the future.