A canonical model for the study of faults in power systems

The authors introduce a general class of fault conditions encompassing all possible faults in a power system, e.g., simultaneous symmetrical and unsymmetrical short circuits, line interruptions, and predicted breaker operations at different locations. The influence of mutually coupled lines, static VAR systems and/or faults at several busbar systems are also considered. The fault conditions are described in both the (three) phase and sequence domains, with the same simplicity. The proposed model of a faulted power system, is in a canonical form, over the general class of fault conditions. It is found that its effectiveness is equal in both domains. The authors also present the model solution procedure for various fault conditions in the general frame of the study of faults. They present the derivation of the canonical model and numerical examples. The application of the canonical model to faults that include buses of distinct voltage levels is stressed.