| 摘要 |
1276964 Standby supply systems; converting INTERNATIONAL STANDARD ELECTRIC CORP 16 Nov 1970 [17 Nov 1969] 54400/70 Headings H2F and H2H A standby power supply system comprises an A.C. to D.C. rectifier unit 2, a D.C. to D.C. regulated converter 6, a battery 3 charged by a voltage regulated battery charger 5 and a thyristor switch 4 for connecting the battery to the output terminals of the unit 2 and to the converter input in the event of mains failure. If the output voltage of the unit 2, or, in the event of mains failure, the voltage of the battery 3 falls below a predetermined value, the converter 6 provides an output across a diode 8 to boost the voltage at output 11. The D.C. supply for the converter so provided by the battery 3 via the switch 4 and the converter comprises parallel arrangements of thyristor bridge inverters THY1-THY4, THY5-THY8 which supply out of phase A.C. signals to transformers TR1, TR2. The transformers are connected to diodes D1, D2 and D4, D5, the outputs from which are connected in parallel across diodes D3, D6 shown as the diode 8 in Fig. 1. The output of the converter is fed to a control and trigger pulse generating circuit (not shown) which controls the thyristor gates so that if the voltage at the output 11 is less than a predetermined value the thyristors are triggered to cause an increase in the mark space ratio of the pulses provided-by the output of the converter. |
