| 摘要 |
1279553 Automatic voltage and current control WANDEL U GOLTERMANN 14 April 1970 [17 April 1969] 17564/70 Heading G3R A D.C. stabilizer of the type wherein a series transistor 7 is controlled by a regulator 10 to maintain a constant output voltage at terminals 9, 9<SP>1</SP> as set by a reference circuit 13 or a constant maximum current as set by a reference circuit 14, is provided with a control circuit 30 which maintains the voltage across the transistor 7 within a predetermined range by firing or cutting off thyristors 5, so that a rectifier 1 supplied from a transformer 2 produces an upper or lower D. C. voltage determined respectively by the thyristors 5 and rectifiers 4 as connected to the ends and to tappings 3 of the secondary winding of the transformer. The upper and lower limits of the predetermined voltage range across transistor 7 are respectively determined by threshold circuits 20, 21 and 22, 23, the former functioning upon occurrence of the upper limit to drive a bistable multi-vibrator 24, 28 into the conductive state to deliver a blocking signal to the thyristor 5 via circuit members 16, 17, 25. When the lower limit is reached the multi-vibrator 24, 28 is blocked by the circuit 22, 23 to supply a firing signal to the thyristors 5. The tappings 3 are chosen so that the difference between the upper and lower D. C. voltages produced by the rectifier 1 is smaller than the predetermined voltage range across the transistor 7. |
