| 摘要 |
<p>An AC motor drive apparatus of this invention is constituted by an AC power source (SUP), a first circulating current type cycloconverter (CC-1) having an output terminal coupled to the AC power source, a phase-advanced capacitor (CAP) coupled to an input terminal of the first cycloconverter, a second circulating current type cycloconverter (CC-2) having an input terminal coupled to the phase-advanced capacitor, and an AC motor (M) coupled to an output terminal of the second cycloconverter. The first cycloconverter (CC-1) controls a current (IR, IS, IT) supplied from the AC power source (SUP) to be a sine wave (ea, eb, ec) in the same phase as that of the power source voltage, so that a voltage crest value (Vcap) of the phase-advanced capacitor (CAP) becomes substantially constant. The second cycloconverter (CC-2) supplies a sine wave current (Iu, Iv, Iw) of a variable frequency (0 to several hundred Hz) to the AC motor.</p> |
