| 摘要 |
A multiple pulse-width modulation power conversion device for variable-speed drive of a three-phase AC motor comprises three units (111, 112, and 113), each unit including n (n >/= 2) batteries (1211, 1212, and 1213), each made up of a DC power supply or at least one battery cell, and n power converters (1311, 1312, and 1313) for converting the DC power of each of these batteries to single-phase AC power. Single-phase AC terminals within each unit are connected in series, and of the single-phase AC terminals within each unit, one of the single-phase AC terminals that is not connected to the single-phase AC terminal of another power converter is connected to a star connection, and the other is connected to a respective one of three input terminals of a three-phase AC motor. The power conversion device further comprises control circuits (1411, 1412, ... 1433) for controlling the power converters such that the AC outputs applied to the single-phase AC terminals of the n power converters within each unit are of the same phase, and further, for effecting multiple pulse-width modulation such that the AC outputs from the three units are separated by an electrical angle of 120 DEG . <IMAGE> |
