This paper presents an efficient controller for washing machine applications employing an on-line energy optimizer. The control scheme is based on a standard rotor flux fieldo-rientation for three phase induction motors. The torque current command is given by the speed regulator whilst the flux current command is given by the energy optimiser. The proper level of flux is selected in order to minimise the motor input power for any speed/torque operating condition. The proposed system does not require any additional measurements with respect to a standard vector controller. Experimental investigations are presented based on a TMS320F240 DSP controller, an IGBT inverter and a four poles, 500 W induction motor for washing machine applications. The system performance and the efficiency improvements achieved by the proposed controller are presented and discussed.
