Characterization of microgrid smart metering: phasor estimation under impaired conditions

The development of smart microgrids requires the adoption of distributed algorithms for energy management and control. In a microgrid, smart meters should also provide measuring functions similar to a PMU with comparable accuracy yet, being connected to a low-voltage distribution grid, they will have to cope with different electrical disturbances. This paper provides an accuracy analysis of known estimation techniques based on interpolated DFT (IpDFT) methods, under the impaired conditions of a low-voltage distribution grid. A brief discussion of expected impairments is provided first, then IpDFT is applied for the estimation of voltage phasors in the neighborhood of abrupt voltage amplitude variations. Results of experiments, run with the aid of an emulated power network, suitable data acquisition devices and signal processing, are presented and figures of merit concerning accuracy performance are discussed.