| 摘要 |
PURPOSE:To make small and light by decreasing numbers of parts by a method wherein a set of commutation circuits are used in common for a chopper unit and a DC switching unit. CONSTITUTION:A thyristor 3 of the chopper unit 2 is controlled by a gate signal fed from a gate circuit 19 and a prescribed DC voltage is generated by a smoothing condenser 24, smoothing reactor 25 and fly wheel diode 26. This DC voltage is applied to an inverter 8 through the DC switching unit 10, the inverter 8 generates a symmetrical 3 phase AC output at the voltage proportionate to a DC input voltage. During this operation, both the thyristors 3, 11 are turned off by the commution circuit 20 provided in common in the chopper unit 2 and DC switching unit 10. For this reason, only a set of the commutation circuits are employed, the number of the parts is decreased and the device can be made small size and light weight. |
