Balanced Truncation Approach to Power System Model Order Reduction

Abstract This article demonstrates the application of balanced truncation based model order reduction to the task of dynamic reduction of power systems. The entire power system is separated into an external area and a study area; dynamic reduction of the external area is conducted. The benefit of applying the balanced truncation technique is that key input–output relationships between these areas are retained during the reduction process. For perturbations originating in the study area, patterns in the dynamic behavior of the external area, such as generator coherency, are well captured by the reduced equivalent. The efficiency of the balanced truncation algorithm is also explored in the context of changing system conditions. Illustrative applications using a test system representative of the northern grid of India have led to some key findings on the coherency of the generators in this grid.

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