TRANSFORMERLESS POWER SUPPLY Russian patent published in 1997 - IPC

FIELD: secondary power supplies designed, for example, to feed electronic electricity meters, electronic voltmeters and wattmeters, miscellaneous protective and automatic-control relays from monitored line. SUBSTANCE: device has excess voltage damping unit built up of two sections with equal AC resistances, bridge rectifier, filter, and two-step voltage regular with second-stage master element current regulating unit, and operational amplifier supplied with power from first step, its output being connected to first load lead. Inverting input of operational amplifier is connected via resistors to leads for connecting first and second loads and noninverting input, via equal-value resistors, to leads for connecting power supply. Device may have two bridge rectifiers whose leads are connected cumulatively and in parallel; each section of excess voltage damping unit has series-connected resistor and capacitor connected through their common point to respective lead for connecting power supply: vacant leads of resistors and capacitors of first and second sections of excess voltage damping unit are connected to respective inputs of first and second bridge rectifiers. EFFECT: simplified design. 2 cl, 3 dwg