| 摘要 |
1,162,918. Rectifying. GENERAL MOTORS CORP. 17 Aug., 1967 [20 Sept., 1966], No. 37969/67. Heading H2F. [Also in Division H3] A steep-fronted trigger pulse for a thyristor connected to a load able to accept a rapidly rising switch-on transient is produced by a first circuit response to a trigger pulse and connected across a first D.C. source and a second circuit responsive to the first to connect a second D.C. source to the gate of the thyristor. If the output of a full-wave rectifier 21 is sufficiently positive, a trigger pulse from 14 causes thyristor 30 to conduct. This renders conducting a fast turn-on transistor 40 and so connects a D.C. supply 24 to the gate of the main thyristor 10 to cause the latter to conduct and energize the load 16. The capacitors steepen the pulse edge. The trigger signals are synchronized with the A.C. supply and a Zener diode 70 prevents excessive voltage on the transistor when triggering occurs at the peak of the cycle. |
