A Novel State of Charge Feedback Strategy in Wind Power Smoothing Based on Short-Term Forecast and Scenario Analysis

Abstract

The battery energy storage system (BESS)-integrated wind farm (WF) has been widely proposed in the literature to reduce the variability of wind power generation. The state of charge (SOC) feedback strategy is a basic and important strategy to keep the SOC of BESS within its proper range while BESS smoothing out the fluctuations of the WF. In this paper, a novel SOC feedback strategy in wind power smoothing based on short-term forecast and scenario analysis is proposed. Other than mainly considering the real-time information in existing strategies, the principal idea of the new SOC feedback strategy is to estimate the SOC varying curve of the BESS in the advance control period with the assistance of the forecasted wind power data. Dynamic SOC margins are determined by scenario analysis to handle the uncertainty in wind power forecast. When the BESS suffers from over-charge or over-discharge in the advance control period, the SOC feedback strategy is then triggered to adjust the BESS output at the current control moment. The effectiveness of the new SOC feedback strategy is validated in case study by using historical wind power data of a WF in Gansu province of China.