Energy storage application in low-voltage microgrids for energy management and power quality improvement

The study deals with the application of energy storage connected to the low-voltage microgrid by coupling inverter for simultaneous energy management and ancillary services that include the compensation of power quality disturbances. The usefulness of storage equipment as a solution to various problems that accompany microgrid development is discussed. Then, the idea is presented to join different tasks the storage can perform in one application. Control algorithm is presented for storage inverter, which enables storage unit to be charged or discharged according to assumed schedule and to contribute to power quality improvement through the compensation of reactive power, current harmonics and unbalance. Effectiveness of compensation is examined on the simulation model of test microgrid. Moreover, the results of tests performed in real test microgrid configured in the Laboratory of Distributed Generation at the Lodz University of Technology are presented in the study.