| 摘要 |
PURPOSE:To prevent the wrong ignition of thyristors of a full-wave bridge type converter, by providing a means for generating two small-width pulses, for one of phase shifting circuits which produce small-width pulses to control the gates of the thyristors. CONSTITUTION:The thyristors Th1-Th6 of a three-phase full-wave rectifier circuit are controlled by small-width pulses from a controller 1 which comprises transformes T1-T3 and porcelain phase shifters which have output windings Ng and control windings NC1, NC2. A pulse transformer PT is coupled to one of phase shifting circuits to generate two pulse signals. One thyristor of a pair determined by the phase sequence of power is supplied with an auxiliary pulse when the other thyristor is supplied with a small-width pulse. This results in smoothly starting the full-wave rectifier circuit through a simple construction, preventing the wrong ignition of the thyristors due to noises and heightening reliability. |
