Abstract
The multi-cell inverter can obtain the high voltage power of a few kV without an output transformer, and has the low distortion and the characteristics of high efficiency. Therefore, the multi-cell inverter is suitable for the use of a power system, and the application to STATCOM or an energy storage system is studied. In the application which a system coordinates, the performance which maintains dc voltage at a steady value is required, taking in the effective power corresponding to loss. However, it is difficult to control the dc voltage of all the cells by the reason of the variation in the characteristics of each cell similarly. Therefore, dc voltage becomes unequal. In order to solve these problems, this paper proposes the system which equalization control of the dc voltage of all the cells. The equalization control uses interphase power decoupling control and inter-cell balancing control. From experimental results using mini model, the good results were obtained.
