Real-time Ring Main Unit (RMU) Monitoring System for Distribution Network

An overhead line is usually used in electric power transmission and distribution system to transmit electrical energy along with large distances. The overhead lines are replaced by underground cables in some areas due to their advantages like less power outage and safety. With the introduction of underground cables, Ring Main Unit (RMU) came into existence. It is a compact, enclosed switchgear used for medium voltage power distribution. This paper mainly focuses on monitoring of the RMU. A monitoring system for RMU is necessary to minimize the time taken to find the fault. The present RMUs installed in HUBBALLI do not have a monitoring system. Hence, there is a requirement for a device that continuously monitors the status of the relay and circuit breaker present inside the RMUs. This paper proposes a device that overcomes the problems faced by unmonitored RMUs. This device checks the status of each feeder of the RMU and intimates to the concerned officers if any change occurs. This change is also reflected in the panel installed in the section office of HESCOM. This device minimizes the time taken to detect the fault in the feeders by reflecting the changes immediately which will in turn reduce the outage of the power supply.