Implementation of permanent magnet synchronous motor drives system suitable for air conditioner application Muhammad Abdul Rahman
Air conditioners are being rapidly used by domestic consumers, industries and offices. Generally, an air conditioner system consists of two motors in the outdoor unit. It consists of a fan and a compressor motor that always running continuously at full speed with on off control technique, and wasteful electric power consumption especially during transient period. This work presents an implementation of a highenergy efficiency Permanent Magnet Synchronous Motor (PMSM) with variable speed drive system suitable for air conditioner application. The motors run continuously with optimum speed operation depend on the load demand. The motor drive system is implemented using two types of motors: surfacemounted and interior type PMSM suitable for fan and compressor motor, respectively. Sensored closed loop Field Oriented Control (FOC) drive is used for Surface mounted Permanent Magnet Synchronous Motor (SPMSM) A simplified Stator Flux Observer (SFO) is proposed for speed sensorless closed loop FOC drive for an Interior Permanent Magnet Synchronous Motor (IPMSM) The proposed SFO eliminates the use of the extended rotor flux in order to estimate the rotor position. A 32 bit fixed point digital signal processor from Texas Instrument, TMS320F2812 board is used as motor controller. The motor drive system was verified and experimentally tested on a 920 W, 4 poles, SPMSM and a 600 W, 4 poles, IPMSM. The step response of speed and load torque is applied to the motor drive system in order to observe the dynamic behaviour of system and the effectiveness of speed and current controller to sustain from sudden change of speed or load.