Introducing Distributed Energy Resources (DER) in distribution systems and high interest on microgrid deployment are fundamentally changing the way that distribution systems are planned, operated, protected, and managed. The conventional SCADA systems for several reasons will not be able to provide adequate monitoring, visibility and control requirements to detect and respond to fast system dynamics introduced by highly variable DERs and/or other grid-edge devices. Synchrophasor measurement technology and phasor measurement unit (PMU) applications, which are primarily introduced and applied at transmission systems, nowadays are slowly finding their way into distribution systems. At distribution levels, PMUs can be applied at specific nodes across medium voltage circuits or on selected laterals, to address challenges brought about by changes in dynamic nature of the system. PMUs provide high resolution synchronized (GPS time-stamped) measurement and multiple point field monitoring that are needed to implement distributed controls and advanced automation schemes.
This paper describes the research, development and demonstration projects on distribution PMU applications performed by San Diego Gas and Electric (SDG&E). The paper focus is on comparing the data monitoring and controls via traditional SCADA systems with those of a PMU system. Several study cases are reported to describe and categorize the technical requirements and issues that support utilization of PMUs for deploying high resolution and time-stamped data measurement outside of the substations. The paper also describes the technology, equipment implementations, and infrastructure that are used in the recent projects to achieve the synchrophasor data transfer and monitoring, both locally (e.g. at substation level), and centralized (at control centre). The primary application would be for system operators to monitor and control the distribution systems and to introduce advanced SCADA visualization and condition-based monitoring of critical assets. Two key topics described in details are PMU placement criteria and performance monitoring indices of interest for operators and planning engineers.
Frank Goodman, Amin Salmani, Farid Katiraei, Shadi Chuangpishit, Mehrdad Yazdanian, Amin Zamani; Presented at the CIGRÉ Canada Conference on Power Systems, Calgary, Canada, Oct. 2018, paper 097
KEYWORDS: Phasor Measurement Units (PMUs), Distribution System, Renewable Integration, Data Monitoring, synchrophasor measurement technology, Distribution PMU (D-PMU)