| 摘要 |
PURPOSE:To switch from power running to regenerative braking in a short time by adding a thyristor to a parallel connection circuit of a forward converter and a backward converter. CONSTITUTION:In case of power running an exciting signal is not given to a thyristor 11, so that an AC voltage supplied by a secondary winding 2b of a transformer 2 is applied to a motor 9 through a forward converter 3, a filter 7 and an inverter 8. In case of regenerative braking the thyristor 11 is excited and a backward converter 4 is in operation. Therefore, a three-phase AC voltage generated by the motor 9 is returned through the inverter 8, the filter 7, the backward converter 4 and the transformer 2. With above configuration the switching from the power running to the regenernative braking can be made in a short time and a circulating current can be eliminated. |
