NO-BREAK POWER SUPPLY UNIT Russian patent published in 2004 - IPC

FIELD: power engineering; no-break dc and ac auxiliary power systems for nuclear power plants. SUBSTANCE: no-break power supply unit that has three-phase mains, three-phase rectifier, diesel-generator set, input selector switch, storage battery, dc buses, first and second inverters, and ac buses is provided in addition with dc voltage regulator and one more three- phase rectifier; storage battery has first and second leads, first one being connected to plus terminal of three-phase rectifier through first and second electronic switches and second lead, to dc plus bus through third electronic switch whose output is connected to dc plus bus and to plus output of dc voltage regulator; output of first inverter is connected to both inputs of second inverter with aid of current transformer, rectifier, L-shaped filter incorporating choke and capacitor, ac buses being connected to outputs of both inverters; second inverter is connected to dc plus bus through fourth electronic switch and to minus bus, directly; mentioned electronic switches are built around diodes. EFFECT: enhanced reliability and voltage stability across buses. 3 cl, 4 dwg, 1 tbl