State-of-the-art Review on Frequency and Voltage Regulation Techniques from Wind Farms

The amount of wind power generation is rapidly increasing. These wind power generators will replace traditional synchronous generators in power systems. Therefore, modern wind turbines must have the similar characteristics of governor and exciter in a traditional synchronous generator to control the real or reactive power outputs by wind turbines. Then, the frequency or voltage stability of a power system can be maintained. In recent years, many studies have proposed various control methods for frequency or voltage regulations, and these methods have different advantages and disadvantages. Thus, this paper will investigate typical and representative control methods for frequency or voltage regulation by wind turbines, and reveal the main principles and key technologies of these methods. Moreover, this paper will provide the future trend about frequency and voltage controls by wind turbines.