Smoothing control of wind farm output fluctuations by using EWMA pitch controller

As wind turbine output is proportional to the cube of wind speed, the wind turbine generator output fluctuates due to wind speed variations. Hence, if the power capacity of wind power generators becomes large, wind power generator output can have an influence on the power system frequency. Some methods for smoothing the wind generator output fluctuations using several types of energy storage systems have been proposed, however, these methods have a cost problem. This paper proposes a new pitch control system for smoothing the wind generator output fluctuations, using a EWMA filtering approach. The simulation results show that the proposed pitch control system is very effective for smoothing the output power fluctuations with random wind speed variations.