Reliability modeling of wind farms considering weather conditions

Wind speed correlation, time variation of wind turbine generator´s forced outage rate (WTG FOR), and dependent failure of WTGs in adverse weather are three factors that affect reliability evaluation of wind integrated power systems. These three factors are related to weather conditions, which can be divided into normal and adverse weather conditions. Although wind speed correlation has been well studied by researchers, the other two factors are not addressed in the existing reliability models of wind farms. A new enhanced reliability model of wind farms is proposed in this paper to effectively incorporate all of these factors. In the proposed model, WTGs are assumed to fail dependently in adverse weather, but independently in normal weather and the dependency of WTG FOR value on weather conditions is considered. Nataf transformation method (NTM) is chosen to simulate correlated random variables for correlated weather conditions, correlated wind speeds, and WTG dependent outages. In order to demonstrate the effectiveness of the proposed model, a series of studies have been carried out on the IEEE RTS with two wind farms added. The results validate the effectiveness of the proposed wind farm model.