Decomposition approach and analysis for a Z-matrix building process

An effective and procedural decomposition approach for Z-matrix building is proposed in this paper. There have been many papers in the literature regarding the Z-matrix building algorithms for large-scale power systems. Those methods mostly emphasised the relationship between the bus voltages and bus current injections. This paper provides a new perspective in observing the relationship. Bus voltages, bus current injections and branch currents were all investigated. The building algorithm can be accomplished by a simple search technique with two proposed matrices and is easily implemented. With these two matrices, the relationships among bus current injections, branch currents and bus voltages can be found. Those matrices will be very helpful in observing the structural changes in short-circuit analysis and contingency analysis. Numerical examples show that the proposed method is very effective and suitable to be used for large-scale power systems.