Patent ID: 6847185
Filing Date: 2005-01-25
Classification: H02P

Abstract:
1. A winding switching device of a three-phase AC motor comprising an AC motor in which a winding having each phase is formed by a plurality of windings and a connecting terminal connecting the windings to each other and both terminals of the winding having the phase are provided on an outside of a motor, winding switching means for properly switching the connecting terminal, and a variable frequency power source for supplying a variable voltage having a variable frequency to the AC motor, wherein the winding switching means includes a plurality of three-phase rectifying means connecting one of ends of the winding having the phase to the variable frequency power source and connecting the other end and the connecting terminal to an input terminal on an AC side of the three-phase rectifying means for each phase, and a semiconductor switch provided to open and close both ends on a DC output side of the three-phase rectifying means.