A Petri Net Strategy for Fault Diagnosis and Location in Power Distribution Systems to Prevent Local Power Shortages

A power distribution system is usually composed of a number of distribution substations and distribution lines, where the latter are fragile and often suffer from faults, leading to serious local power shortages. For all distribution substations, it is complex and costly to diagnose and locate faulty input lines from the multiple input lines of distribution substations. This paper reports a Petri net strategy to diagnose the faulty input lines to prevent local power shortages. The structure of a supervisor is proposed to detect and locate the faulty input lines by supervising the variations of power loads that are stored in a battery energy storage system. The stored power loads can be uninterruptedly distributed to the output lines during the fault diagnosis processes. Moreover, there are other auxiliary distribution substations that can urgently supply power loads to a distribution substation once the faulty input lines of the distribution substation are diagnosed. The local power shortages of the distribution substation are prevented during the fault diagnosis processes. In addition, the structures of power distribution systems and their control systems are formally defined by using Petri nets. The derivation processes of fault detection and location strategies are verified by the mathematical methods of Petri nets. Finally, a case study is presented.