Constant Control during the Designated Time for Grid Code of Long-term Fluctuation of Wind Turbine Generator Systems and Forecast Error Adjusting Method

Abstract

For the carbon neutral society, installation of renewable energies is increasing. In particular, expectations for Wind Turbine Generator Systems (WTGSs) have raised in Japan. However, since output of the WTGSs fluctuates, it may cause difficulty in the operation of the electric power system, such as reduction of frequency stability by the imbalance of power supply-demand. As a measure, transmission and distribution companies introduced grid codes for WTGSs. Therefore, Energy Storage System (ESS) is usually used to satisfy the grid code. However, because the ESS is expensive, kW and kWh capacity should be small. Therefore, this study proposes the constant control during the designated time by using forecast to reduce the ESS capacity requirement while satisfying the grid code. In addition, as measures for the forecast error, kW and kWh adjustment considering renewal are proposed too. The result by simulation showed that the proposed method can reduce 36% of ESS capacity compared to the conventional method.