| 摘要 |
Apparatus for controlling the voltage on a commutating capacitor in a thyristor time ratio control power circuit whereby the energy stored in the capacitor may be continuously adjusted to a magnitude required for commutation so that the size of the commutating circuit can be significantly reduced. An inductive circuit is provided in a charging current path for the capacitor so that the capacitor can be charged above available source voltage by capacitive/inductive action. A controllable switch connected in parallel with the inductive circuit provides a short-circuit path for terminating charging of the capacitor. A logic circuit monitors capacitor voltage, source voltage and load current and closes the controllable switch when the capacitor voltage reaches a magnitude established by the logic circuit as sufficient to commutate the measured magnitude of load current. |
