Power Flow Optimisation and Grid Integration of Wind Turbines with the Doubly-Fed Induction Generator

In this work the integration of wind turbines with the electrical network as a conventional energy supplier is focused. A procedure to reduce the electrical losses on a doubly-fed induction generator drive and to attend to the new requirement of the power companies on wind energy conversion system is presented. The method is based on the control of the reactive power flow on a back-to-back converter consisting of 2 IGBT-inverters connected by a DC-link. The machine and mains side inverters allow together with the active power balance between generator and mains supply the production of reactive power on both rotor and net-side independently. The output LC-filter contribution is also taken into account. Experimental results from a 4 kW test bench are shown