| 摘要 |
PURPOSE:To make generation of commutation failure to hard and to protect an inverter by a method wherein a core is inserted in a current-limiting reactor to enlarge inductance thereof, and turn-off time at the trough of full-wave rectification is elongated. CONSTITUTION:An AC voltage supplied from an AC electric power source is rectified by a rectifying circuit 1, and is supplied to the inverter 4 through the current-limiting reactor 2. The core 3 is inserted in the current-limiting reactor 2. The inverter 4 is consisting of a switching device of thyristor, etc., and the first recovery diode, etc., and is performing proper frequency switching operation. When the core is inserted in the current-limiting reactor 2, because turn-off time is elongated, generation of commutation failure is made to hard. |
