| 摘要 |
PURPOSE:To average the quantity of energy which is stored in or released from a coil by a means wherein a thyristor converter is composed of plural units so that the converter can be switched to series or parallel connection if necessary. CONSTITUTION:In the initial stage of an energy storage period t1-t2, a switch 6 is closed, other switches 7, 8 are open and converter units 21, 22 are connected in series with each other. As a result, DC voltage double that of a single unit can be outputted. At the time t5 when the current of a coil becomes almost a half of a rated level, the connection of the converter units is shifted from series to parallel, the switches 7, 8 are closed and another switch 5 is opened. The shifting can be also effected by closing a switch 51, opening a switch 52 and disconnecting a thyristor converter from the coil for a short time. In the second half of the storage period t5-t2, a DC voltage becomes a level corresponding to a single unit but amperage becomes double. |
