ENERGY STORAGE DEVICE HAVING UNBALANCE CURRENT COMPENSATION FUNCTION IN THREE-PHASE SYSTEM

摘要

The present invention relates to an energy storage device having an unbalance current compensation function in a three-phase system, which maintains an unstable frequency and a voltage level of a system through output current in the energy storage device and corrects the unbalance current by applying a power conversion device of a three-phase four-wire voltage-type inverter which senses the current of the system. Four phases (R, S, T, N) are controlled using the three-phase, four-wire voltage-type inverter. The R, S and T phases have an output function and the N phase acts as a loop to allow an unbalanced current to flow in the inverter, but unbalance the DQ conversion-based three-phase output using the average value, calculates the unbalance value of the three-phase from the unbalance load current, calculates the minimum value and the maximum value of each phase to acquire the average value, individually determines the output as the unbalance current of each phase by subtracting the average to each phase, and controls the N-phase from the value to correct the value as the unbalance current in the inverter.;COPYRIGHT KIPO 2017