Smart Meters for Microgrids

Nowadays the primary goal of the electric power industry is modernization on the basis of new technologies and network equipment such as distributed generation, smart grids, smart meters, intelligent electronic devices, etc. One of the requirements imposed on smart grids is improvement of power quality. Moreover, of great importance for the power quality improvement is, in particular, decrease to a minimum in high harmonics in supply voltage. The problem posed by the authors is topical since high harmonics in supply voltage considerably decrease the efficiency of electric equipment. There are publications that address various methods for calculation of an expected harmonic spectrum, if the voltage-current characteristic of nonlinear consumer is known, and describe experimental methods for harmonic measurement. Normally, these publications are of academic character and cannot be used in practice. The complexity lies in the fact that the spectral composition of voltage in system depends on many factors and is virtually of random character. The meter suggested in the paper is intended for separate measurement of the energy of high harmonics and the energy of fundamental harmonic. It can provide objective data for identification of the harmonic source.