| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an inverter in which a reverse bias can be applied to a gate terminal of a switching element with a non-insulating and simple power source circuit to overcome a conventional inverter in which when a size is increased, it is necessary to raise noise resistance and to apply a lower voltage to the gate terminal than a source (emitter) terminal to turn off the switching element thus causing a circuit configuration to be complicated. <P>SOLUTION: The inverter comprises: an intermediate voltage power source circuit for converting to lower a voltage from a DC source of a drive source of a three-phase bridge circuit and an AC motor to an optimum voltage to turn on the switching element without insulation; an off-power source circuit receiving a power source supply voltage from the intermediate voltage power source circuit and which can lower the voltage from the source (emitter) of a low side switching element to a gate; and a non-insulating low-level power source circuit for converting the output voltage from the intermediate power source circuit to a further lower voltage. <P>COPYRIGHT: (C)2004,JPO |
