A sensorless voltage control of stand-alone induction generator with PWM converter for renewable energy applications

This paper presents a deadbeat current control strategy for a stand-alone induction generator (IG), working with variable speed and load to regulate both the IG terminal voltage and the dc-bus voltage of the pulse-width modulation (PWM) converter. The deadbeat current controller is a good application for the IG to reject the IG terminal voltage sensor. Furthermore in the proposed system, not an encoder but a newly designed phase locked loop (PLL) circuit is used to determine the stator voltage vector position of the IG. PWM converter does not control the frequency of IG but it works in synchronizing with the IG frequency by using the phase information of the PLL circuit. A 2.2 kW laboratory prototype has been built to confirm the feasibility of the proposed method.