Nonlinear observer-based speed control of a synchronous reluctance motor

This paper presents a design for a closed-loop sensorless control scheme for a synchronous reluctance motor. The sensorless controller operates in an estimated dq reference frame and is a combination of an input/output linearization speed controller and a full order nonlinear observer. The control scheme is implemented in the laboratory using a real-time DSP, a three-phase inverter, and a 100 watt motor. The implementation does not require measurement of the motor terminal voltage and, instead, relies on compensation for the nonideal behavior of the inverter. Experimental results show successful tracking of a varying speed command.