SOURCE OF THREE-PHASE VOLTAGE WITH CONTROLLED ASYMMETRY Russian patent published in 1994 - IPC

FIELD: electrical engineering. SUBSTANCE: source of three-phase voltage with controlled asymmetry has unit 1 of asymmetry control with generator 3 of single-phase sinusoidal voltage to which output three line voltage dividers 4-6 are connected in parallel being provided with monitoring devices 7 and phase inverters 12 across their outputs and four voltage transformers 8-11. First leads of primary windings of transformers 8-10 are connected to outputs of proper voltage dividers. Second leads of primary windings and common terminals of voltage dividers are ties to body of unit of asymmetry control. First network of first secondary windings of transformers 8-10 connected in series aiding is linked with one end to first output terminal of unit for asymmetry control and with other end - to fourth output terminal. Second network of second secondary windings of transformers 8-10 is connected with one end lead to fourth output terminal. Second secondary windings of transformers 9 and 10 are interconnected in aiding and in opposition to second secondary winding of transformer 8. Secondary winding of transformer 11 has midpoint tap coupled to other end lead of mentioned second network, second and third output leads of unit of asymmetry control are linked to first and second end taps of secondary winding of transformer 11 which primary winding is coupled to output of phase inverter 12 connected with input between outputs of voltage dividers 5 and 6. It has 90 degrees voltage shift across output of phase inverter with reference to voltage across its inputs. Transformation ratios by first secondary windings and by second secondary windings of transformers 8-10, transformer 11 and transmission ratio K₅ of phase inverter determined as relation of amplitude of output voltage of phase inverter to amplitude of its input voltage conform to relationship 2:2:2: 2: 1: 1: 2 . EFFECT: increased accuracy and adaptability in setting asymmetry. 1 dwg