| 摘要 |
PURPOSE: To realize reduction in size of the apparatus as a whole and fabrication cost thereof by simplifying a structure of the power supply for driving a switching element. CONSTITUTION: An inverter apparatus is formed in the structure that six IGBT 3 to 8 are connected, by the 3-phase bridge connection, between a positive power supply line 1 and zero-potential power supply line 2 and a control signal from a control circuit is applied to the gates of IBGT 3 to 8 through photocouplers 25, 29, 32, 35 to 37. Moreover, a DC power supply circuit 45 is provided as the common power supply for driving the gates of the zero potential side IGBT 4, 6, 8 and the drive capacitors 50, 53, 56 are also provided as the power supplies to drive the gates of the positive side IGBT 3, 5, 7. In addition, charging circuits 52, 55, 58 are also provided to charge the drive capacitors 50, 53, 56 from the DC power supply circuit when the zero-potential side IGBT 4, 6, 8 turn on. |
