| 摘要 |
PURPOSE:To shorten a time interval during which a power system is adversely effected by resuming operation of a cycloconverter upon reset of primary winding voltage and controlling the current flowing through an overvoltage suppressing circuit to zero. CONSTITUTION:When the source bus voltage is normally reset and an overvoltage suppressing circuit is operating, a control circuit 11 outputs a signal (c) for switching a relay 13A and (d), (q) axes current command values IdRY, IqRY for taking in current, equal to the current flowing through the secondary winding of an induction machine, are provided to a cycloconverter control circuit 50. At the same time, contact of a relay (e) is switched by an output from an OFF delay timer 11H and a primary delay circuit 13B is inserted into the circuit in order to suppress abrupt variation of output. Consequently, current flowing through the overvoltage suppressing circuit drops below a predetermined value and normal reset takes place. |
