Power quality in power supply systems of mining and processing enterprises in Russia

This paper investigates the effect of load factor frequency converters and thyristor on electrical power quality. Recommendations for reducing influence higher harmonics switching overvoltages characteristics are provided. Higher were measured by a PKK57 complex device controlling parameters digital oscilloscope Tektronix TDS 2024V type. Impulse recorded an active resistance divider DNEK-10 type above-mentioned oscilloscope. The obtained data processed Loginom 6.4 software methods mathematical statistics. lower threshold level was set equal to 0.8, at which sinusoidal distortion voltage curves correspond RF standard suppression degree from 5th 17th transformers with capacity 250–6,300 kV. A ranged 95 45%. use ‘transformer–converter–electric receiver’ system as applied supply systems mining processing enterprises substantiated. It shown that electric motors up 2,500 kW inclusively require protection against overvoltages. Conventional RC-absorbers based RC-circuits connected terminals be highly efficient protecting Thus, quality in Russia can ensured 0.8 or greater. Provided transformer does not exceed 1,000 A, more less expensive ‘transformer–converter–electrical is recommended. Effective inclusive provided using proposed conventional RC absorber, maintains overvoltage rate exceeding 1.7.