CONTROLLING SYSTEM FOR MULTILEVEL INVERTER AND CONTROLLING METHOD FOR THE SAME

摘要

According to an embodiment of the present invention, provided is a system for controlling a multi-level inverter, which is capable of uniformly controlling direct voltages among cell inverters. The system comprises: a multi-level inverter having multiple cell inverters which are connected to each other in series; a primary controller to calculate voltage command values to output target current values to a grid; and a cell controller to detect phase values of the voltage command values and phase delay values of output voltages, to compensate for the phase delay values to the phase values for each of the cell inverters, and to calculate final voltage command values.