Comparison of μPMU and PMU

Phasor Measurement Units (PMUs) have been used for several years to record information on power system, especially in transmission system. Their ability to synchronize to Global Positioning System (GPS) time, enables them to make accurate measurements of angle differences. However, due to their cost and the small angle differences they are rarely used in distribution system. The recently developed micro Phasor Measurement Unit (μPMU) claims a capability of micro-second resolution and milli-degree accuracy, which is 100 times the resolution of traditional transmission-type PMU. Therefore, μPMUs could be an extremely useful tool for distribution systems and microgrids. To better understand the advantages of μPMUs compared to traditional PMUs, this paper provides the experimental results of a comparative testing of these two devices based on the C37.118.1 standard for Synchrophasor [1].