| 摘要 |
PROBLEM TO BE SOLVED: To obtain an inverter apparatus which uses a bipolar transistor, in which carriers between its base and its emitter in a turning-off operation are extracted safely and efficiently and in which a switching loss can be reduced greatly. SOLUTION: In this inverter apparatus, a pulse signal which is pulse-width- modulated for every phase is obtained on the basis of a three-phase sine-wave input and on the basis of a triangular-wave carrier signal. On the basis of the pulse signal, a drive circuit 4 switch-controls transistors 1012 and 1014 which constitute the transistor bridge of an inverter circuit. Electric power is supplied to each phase of a three-phase load. In this case, the outputs of the transistors, which constitute the transistor bridge or/and the drive circuit 4, are coupled capacitively to a ground side terminal or a power-supply side terminal of a pre-stage transistor by the transistors. |
