Distributed power quality monitoring

One of the most important characteristics of the electric power system is its observability. The observability is essential not only for the power flows and power supply reliability indices, but also for the power quality indicators, particularly for the nonsinusoidality of supply voltage waveform. The wide use of power electronics components in intelligent electric power systems, which will increase in the future, leads to the occurrence of harmonic voltage and currents. Moreover, the electric power system facilities can be represented by both the sources and the consumers of high harmonics []. In this connection the assessment of impact of individual facilities on the power quality is a topical problem. The observability of electric power systems can be provided with the use of phasor measurement units (PMUs). The paper proposes a distributed power quality monitoring system based on the available PMU infrastructure to continuously control the level of high harmonics in different cutsets of the electric power system.