Research On Evaluation Indices For Reliability Of Grid-connected Wind Farms

As wind power develops rapidly, there are lots of problems appear when wind power connects grid, of them, the most important thing is reliability. Compared with conventional power supply, wind power has strong randomness. Conventional reliability evaluation indices for power supply such as loss of load expectation (LOLE), expected energy not supplied (EENS) can not show directly the contribution of wind farm to power system reliability. Therefore, the research and development on the reliability indices of wind power to their own specific measure and establishment of wind power complete theoretical system on reliability evaluation are greatly necessary.On the basis of the analysis to factors affecting the wind farm's reliability, this paper proposes a tree-like four-story evaluation system, which uses fuzzy-AHP as evaluation method. All these form a complete reliability evaluation system in theory. The evaluation system has advantage, which considers the economy as an important factor affecting the reliability. All these meet the market requirements. Also, the paper makes evaluation example to demonstrate the application process, so that research has a certain theoretical level and practical value. In addition, the paper analyzes the indices' changing properties and laws when lower-level indices of wind farms are changed. Meantime, on this basis, the effective ways to improve wind farm's reliability are proposed.These evaluation data and analysis results provide an important reference to study economic and true value of wind power. They can be used as an important reference for wind farm investors, as well as some help for the design of wind farms. Besides, they not only run certain significance for the wind farm planning, but also are the basis for the Government to formulate policies and the power companies to determine electricity price. Lastly, they make greatly contribution for wind power to healthy development.