PITCHY: A pithch controller to minimize frequency fluctuation in hybrid power systems

Abstract

Wind energy is widely considered as a major source of clean energy. As such, wind turbines are becoming popular in the renewable energy world. The output of the wind turbine varies with randomly changing speed of the wind. This is a critical problem for wind turbines in general, and fixed speed wind generators in particular. However, conventional pitch controllers and governor control systems are not capable enough to keep the power system frequency to the expected stage. By using variable reference line power in pitch controller of wind turbine, frequency fluctuation can be minimized significantly. In this paper, we propose PITCHY, a novel pitch controller to minimize output frequency of wind turbines. PITCHY minimizes frequency fluctuation by generating reference power using low pass filter (LPF). We design a simulation model and evaluate PITCHY using PSCAD/EMTDC. We used a number of wind (induction) generators having varying governor control systems in our simulation. The results show that using PITCHY power system frequency fluctuation can be varied from 49.9 to 50.1 Hz.