Adequacy Study On Power System Containing Wind Farms

As the worldwide energy crisis and environmental pollution are becoming increasingly serious, countries around the world have begun to develop and utilize new energy actively. Wind energy is attracting more and more attention due to its clean, no pollution and renewable nature and wind power is regarded as an important alternative to traditional fossil fuels because it is easy to implement with low operating costs and it doesn't require any fuel in generation process. However, the intermittent and uncontrollable natural of wind speed has an impressive effect on the output power of a wind farm and the reliability of power system, so it is necessary to evaluate the power system adequacy containing wind farms.In order to discus the impact of terrain influence and wake effect on the wind farm output and power systerm reliability indices, this paper proposes a Monte Carlo simulation technique to evaluate adequacy of wind farms with considering wind speed random variation, WTG reliability, hilly terrain influence and wake effect. A quadratic interpolation method is used to study the optimal distribution of WTGs in a wind farm.The main content and conclusions are as follows: (1) The theoretical principles of Monte Carlo simulation technique, the advantage and disadvantage of analytical technique, non-sequential and sequential Monte Carlo simulation are introduced. An example is used to illustrate that sequential Monte Carlo technique is more accurate.(2) An essential prerequisite in adequacy analysis of a wind farm is to realistically simulate the hourly wind speed. Weibull distribution and several ways to estimate Weibull distribution parameters are detailed in the paper, such as mean wind speed and standard deviation, mean wind speed and fastest wind speed, least-squares and maximum likelihood. An example is used to show that the mean wind speed and standard deviation method is more available depending on actual wind data.(3) A wind farm reliability model considering wind speed random variation, WTG reliability, hilly terrain influence and wake effect is established. Wind farm outputs with and without considering terrain influence and wake effect are investigated in this paper, and the results show that the terrain influence and wake effect will have a great impact on the wind farm outputs.(4) Based on the wind farm dynamic analysis principles, a quadratic interpolation method is proposed to study the optimal distribution of WTGs in a wind farm. Reliability of a wind farm with and without the optimal WTG distribution are investigated by using the proposed technique. The results show that, the optimal layout of wind farm will reduce the wake effect of WTGs and increase the outputs, and will make a great contribution to the power system reliability.