An optimal control strategy of a variable speed wind energy conversion system

In this paper a method of tracking the maximum power in a wind energy conversion system is presented. The control algorithm does not require measurement of the wind velocity. In order to absorb maximum power from the wind turbine, speed control of the synchronous generator is required. To achieve this control, an AC-DC-AC converter is interposed between the stator of the generator and the utility grid. The AC-DC rectifier consists of power diodes and the DC-AC inverter consists of thyristors. With proper control of the firing angle of the thyristors the maximum power tracking is achieved. The control strategy is based on the form of wind turbine´s power-speed characteristic curves. The simulation system consists of a simulated wind turbine and a synchronous generator.