Mobile Application for Power Substation Monitoring for Maintenance Operations

Abstract

Power substations are the most critical units of any electricity supply system. These substations either step down or step up voltages from one level to another, or maintain the same level of voltage for interconnections. Substations that operate at medium to high voltage levels have critical components such as transformers, circuit breakers, protection relays, DC batteries among others, that require regular monitoring and analysis for maintenance operations. These components also detect potential anomalies that could lead to unplanned outages and system failure. In this paper, we present an automated monitoring system that enables authorized substation operators to remotely access and receive critical substation information on trips and alarms necessary for rapid maintenance response and intervention of faults. At the crux of the monitoring system is a hardware controller system which has a microcontroller, relays, and shift registers, for acquiring and processing signals from the transformer control panel at the substation. The controller system, which also functions as a data logger, communicates the substation data to a cloud server using the GSM/GPRS (Global Service Mobile/General Packet Radio Service) communication protocol. A user interface system on a mobile device interacts and access prevailing conditions at the substation from the controller system through the server system. A prototype of the substation monitoring system design was implemented and tested through numerical simulation and field tests at a 33/11kV substation of the ECG (Electricity Company of Ghana). The results show that authorized substation operators are able to remotely monitor and receive in real-time, critical substation information such as alarms, trips, warnings, and the winding loads on transformers necessary to facilitate rapid maintenance to avoid system failures and shut-down.