Modifying power curve of Variable Speed Wind Turbines by Performance Evaluation of Pitch-Angle and Rotor Speed Controllers

Abstract

The Power curve of wind turbine ignores the dynamic behavior of the wind and represents the wind turbine power as a function of the average wind speed. Power curve is not an adequate tool for estimating the power of variable speed wind turbines. Because, in addition to average wind speed, the output power of these turbines is highly dependent on the dynamic of the wind. In this paper, by introducing a new curve named controllers power curve, a method is presented to modify power curve of variable speed wind turbines according to the wind dynamics. The controllers' power curve is a 3-D curve that represent the amount of electrical power that generated because of controllers' performance taking to account the wind characteristics and reactions of controllers to instantaneous wind speed variations. In proposed method, the EPF of the wind represents the wind dynamics. Also the controllers' performance is simulated using a new factor named controllability factor. Simulation studies showed the effectiveness of the proposed method based on controllers' power curve.