An energy function based contingency screening method for ATC assessment with transient stability constraints

For the effective use of power system under the deregulated environment, it is important to make a fast and accurate evaluation of the maximum available transfer capability (ATC) from a supply point to a demand point. An ATC assessment requires (n-1) security assessment under multiple supply/demand scenarios. An ATC assessment with transient stability constraints (transient stability ATC) involves a huge computational burden and has a dominant part in overall computational cost of ATC assessment. In this paper, a novel contingency screening method for transient stability ATC assessment is proposed, which utilizes a contingency severity index obtained by an energy function approach. This severity index takes into account the influence of the transaction under study on severity of contingencies. Numerical example shows that the proposed method is proven to be an efficient method to find the severest contingencies from the viewpoint of ATC assessment.