Low cost PWM converter for utility interface of variable speed wind turbine generators

Abstract

In this paper, a low cost PWM power converter for a variable speed wind turbine generator (WTG) is discussed. A six-switch PWM converter is utilized to convert a three-phase power from a WTG to a single-phase electric utility. The proposed converter consists of two stages. The first stage is a variable frequency PWM converter with 4-IGBTs to control the output power of the generator. The second stage employs 2-IGBTs to return the power to the electric utility. These two stages have common DC-link. The utility output current is sinusoidal with a good quality. Suitable PWM control via space vector modulation is designed to control the generator. Current regulated PWM is used to control the utility side. Results from the simulation of the power converter are presented in this paper. The proposed converter is suitable for utility interface of WTGs up to 20 kW ratings.