Development of a network-based power quality diagnosis system

This paper presents a network-based power quality (PQ) diagnosis system. In accordance with the IT development, PQ monitoring networks are prevalent in many existing systems because such networks can provide system-wide insights to users. The developed PQ management system of this paper also consists of network-based devices such as PQ monitoring systems (PQMS), the PQ Server, and the PQ diagnosis system (PQDS). PQMSs measure power quality data at various points in the power systems and send them to the PQ Server through the Ethernet. The PQDS diagnoses the PQ data stored in the PQ Server in order to provide various diagnosis functions to the users. However, in many existing PQ monitoring networks, it is still difficult to pin-point the event location and to find appropriate solutions. The developed PQDS focuses on identifying power quality events, especially on finding the fault location and the type of faults as well as various statistical and stochastic analyses. Therefore, it can help users cope well with power quality problems with the right measure in the right place. The PQ diagnosis system also provides event trend diagnosis, stochastic diagnosis, and PQ indexing functions for user convenience.