Western interconnection experience with phasor measurements

The demand for reliability has placed emphasis on service restoration and has highlighted the need for more precise exercise of the art and science of protection & control both for local as well as the more complex schemes protecting the integrity of the interconnected grid. Understanding the complexities of the interconnected power grid and the need for proper planning, comprehensive maintenance, and sound operating practices is the key to reliability and preventing the problems of tomorrow. Advanced analysis, and operational tools and application of latest technologies such as Synchronized Phasor Measurement Units (PMU) are imperative to tackle phenomena (stability detection, reactive power management, load encroachment, etc.) that continue to affect grid reliability. This paper addresses improvements in technology and application of PMUs for wide area measurements and practical visualization of the measurements in multifaceted power delivery system. Performance of Phasor measurement units (PMU) and challenges associated with use of different technologies (manufactures and algorithms), industry efforts to identify the standard requirements for PMU, and some of the initiatives in North America associated with interconnection phasor measurement requirements are summarized. Some applications of protection and control of synchronized phasors designed as part of wide-area protection and dynamic control schemes are covered. Challenges for use in such precision applications, and the experiences to date in the Western part of the North America are also presented. Sample recordings of synchronized phasors recent during system disturbances in the Western North American grid are also presented. The many variables and the precision requirements in protection and control applications are discussed and methodology for and optimum design is explored. Discussion on architecture alternatives for high availability that will drive for redundancy is discussed at the conclusion of this paper. The lessons learned from installed base PMU systems can be applied towards complex grid integrity protection applications and advanced wide-area warning systems for a more robust power delivery.