Reliability Analysis Of Generation And Transmission Systems Integrated With Wind Farms

The wind has stochastic volatility, so the large scale wind generation connected to grid has adverse effect on the reliability stability of power systems. Reliability of power systems is one of important indices which have directive significance for the plan, operation and maintenance of power systems. So the paper analyzes the reliability of composite generation and transmission system including wind farms.The paper systematic introduces the assessment progress of composite generation and transmission system including wind farms. Which mainly include:wind speed simulation, reliability model and reliability analysis method. On the forecast wind speed of wind farms, the paper proposes a hybrid algorithm integrating wavelet decomposition and time series analysis. The non-stationary time series change to stationary time series of different scales by wavelet decomposition, then refactoring to original scale and forecasting the each layer wind speed by time series analysis. These methods improve the forecasting precision of non-stationary wind speed. In the reliability analysis method, the paper setting up outage models of wind and conventional generators, which mainly include independent outage model and common outage mode etc. Through the virtual components to define common outage that it effective covers the independent and common outage. In the reliability analysis method, Monte Carlo simulation has low efficiency. So the paper will use layered important sampling technology in reliability evaluation. According to the important degree and category of system components, the system state space is separated into different levels of subspace. It will optimize the system important sampling function gradually. So the later algorithm will have more advantage.It avoids the degeneration phenomenon of conventional sampling in the higher reliability system and improves the calculation efficiency.The paper writes the reliability simulation program for IEEE-RTS79base on wind speed model, reliability model and reliability analysis method by Matlab7.0. The main analysis content includes the change of reliability level when wind farms access system by different capacity, and then calculate the effective load carrying capability of the wind farm. The simulation analysis explains the wind farms influence on the reliability of composite generation and transmission system. And also verify the efficiency and adaptability of the paper’s reliability algorithm.