SECONDARY POWER SUPPLY Russian patent published in 2000 - IPC

FIELD: electrical engineering; stand-by power supplies. SUBSTANCE: power supply has supply mains condition sensor, adjustable converter, ON/OFF unit, storage battery charge/discharge unit, and devices for changing the load over from power mains to battery supply and vice versa, all built around comparators. Converter is connected to load through isolating diode; first lead of diode anode is connected to battery charging circuit set up of series-connected part of choke coil, inductive- capacitive filter, converter, and diode which are connected in parallel with capacitor; second lead of battery charging circuit is connected through limiting resistor to plus terminal of storage battery; discharging circuit of storage battery is connected through transistor collector to isolating diode cathode and through transistor emitter, to plus terminal of storage battery; base output of transistor is connected through switch to comparators detecting condition of converter and battery power equipment. Such arrangement provides for connecting storage battery directly to battery discharge control transistor without auxiliary components within desired rate of discharge. EFFECT: simplified design. 1 dwg