| 摘要 |
1293180 Standby battery charging systems SOC DES ACCUMULATEURS FIXES ET DE TRACTION 24 Dec 1969 [27 Dec 1968 1 Oct 1969] 62944/69 Heading H2H Apparatus for charging a battery forming part of an electrical standby supply system comprises an auxiliary battery which is charged by the main battery during the failure of the A.C. supply when the battery is maintaining the supply to the main load or supplying an auxiliary load, the main battery being recharged at a rapid rate when the A.C. supply is restored for a time dependent upon the degree of charge acquired by the auxiliary battery. In an apparatus for the provision of emergency lighting the main lighting apparatus (not shown) is supplied from an A.C. source 2, a main battery 1 being maintained fully charged from the A.C. source 2 by means of a trickle charger 3. When the A.C. source fails a relay 5 is de-energized, closing contacts 19, 20, 21 and opening contacts 22, 23. The battery 1 then supplies the auxiliary lighting 9 over contact 21 and a resistive shunt 8. The stabilized voltages obtained from the zener diodes Dz 1 , Dz 2 are used to apply constant bias to the amplifier 10 and to the circuit 11 so that the volt drop across the shunt 8, which is a measure of the value of the current flowing in the lighting load 9 causes a transistor T 4 to conduct accordingly whereby an auxiliary battery 12 is charged by the main battery 1 in accordance with the value of the discharge current of the battery 1. When the A.C. source 2 is restored the relay 6 is energized thereby changing over contacts 19-23. The battery 1 is then disconnected from the load 9 and the auxiliary battery 12 is connected to bias transistor T5 into conduction. Transistor T6 then causes a relay 6 to become de-energized thus closing contacts 24 whereupon the battery 1 is recharged at a high rate by a charging apparatus 4. As the battery 12 discharges the transistor will eventually cause the relay 6 to re-open contacts 24 whereupon the charge of the battery 1 is maintained by the trickle charger 3. In a second embodiment the battery 1 is arranged to energize the same lighting apparatus as the A.C. source 2 and the apparatus is arranged to permit the battery 1 to be recharged for a pre-determined time and to permit the battery temperature to effect the rate of charge. In a second embodiment the element 4 can be arranged to alter the charging voltage level of the element 3 to provide the rapid rate charging. |
