| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a three-phase inverter circuit which can give free wheel action to a first semiconductor element by lessening the control power to a second semiconductor switch element, and also can interrupt a short circuit in the case where a short circuit accident has occurred in one or the first semiconductor switch element. <P>SOLUTION: In a three-phase inverter circuit where three converting circuits include two switch circuits on positive electrode side and negative electrode side each and the junctions between these two switch circuits are connected each to three-phase AC terminals, each switch circuit has a first semiconductor switch element which switches on or switches off, in controlled phases, DC voltage and a second semiconductor switch element which is connected in parallel with this first semiconductor switch element, in reverse polarity to it. The second semiconductor switch element in each switch circuit is constituted of a voltage control type of semiconductor switch. <P>COPYRIGHT: (C)2008,JPO&INPIT |
