Real-time short-circuit analysis of active distribution systems

In this paper a real-time short-circuit calculation method for large-scale distribution systems with a high penetration of distributed generators is proposed. Recent years have witnessed increasing penetration of distributed generators. Thus, distribution systems have become active, where the fault current flow is no more straightforward. Additionally, modern distributed generator's models differ from the classical synchronous generator's models. Hence, traditional short-circuit calculation methods are not applicable in today's systems. The proposed method is based on the superposition theorem. An improved back/forward sweep in the sequence domain is used for calculation of the faulted system state. Results show that the proposed method is highly accurate and particularly suitable for real-time applications in large-scale systems, where the calculation time is of critical interest.