Abstract：Current methods,such as Copula theory,are inadequate to model multiple dependent wind power outputs accurately.Moreover,the point estimate method cannot handle the correlation among wind power outputs.Thus,an improved point estimate method based on Pair Copula and probability integral transformation is proposed for probabilistic load flow studies.The probabilistic model of multiple correlated wind power outputs is firstly constructed by Pair Copula.The point estimate method is then used to generate samples in the independent normal domain.Finally,based on the probability integral method,the samples are transformed into the actual probabilistic domain in order to find the characteristics of the power system operation.In this way,the point estimate method can handle multiple dependent wind generations with arbitrary distributions.The modeling and analysis for the power outputs of adjacent wind farms in Australia verify the goodness-of-fit of Pair Copula.The probabilistic load flow of the IEEE 118-bus system is solved to demonstrate the effectiveness of the proposed method.
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2015, Vol. 30 
