Integrated approach to online system wide power quality monitoring

SP PowerGrid Ltd is responsible for the management and maintenance of transmission and distribution (T&D) network in Singapore. The T&D network comprises 400 kV, 230 kV, 66 kV, 22 kV and 6.6 kV systems with over 9000 substations that are electrically connected by a fully underground cable system spanning more than 25,000 kilometres. In our proactive effort to meet power quality challenges head on, SP PowerGrid has put in place a comprehensive power quality program. Setting up an online integrated power quality monitoring system (PQMS) is one of many initiatives of the program. The PQMS monitors, analyses and benchmarks the power quality performance of the system, and provide useful data for network operations amongst others. This paper presents the design concepts, technologies, complexities and challenges faced in setting up the online integrated PQMS. Practical implementation issues are also discussed.