| 摘要 |
1,096,555. Semi-conductor pulse circuits PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. Nov. 10, 1966 [Nov. 13, 1965], No. 50453/66. Heading H3T. [Also in Division H2] A circuit providing a constant angular delay with variations in frequency for firing thyratrons or thyristors 1, 2 comprises a capacitor 19 which charges when a half-wave voltage Eb is positively increasing, and discharges when a higher half-wave voltage Ea drops below the peak Eb value. A transistor 21 conducts at the end of each charge and discharge to allow a gate and trigger circuit 26 to pass firing pulses to thyristors 1, 2. As the frequency varies, the time to charge and discharge capacitor 19 varies inversely hence keeping the firing angle substantially constant. The arrangement may be incorporated in an inverter for an inductive heating arrangement 9, 10 as shown or in a voltage stabilizing circuit, or rectifier. |
