| 摘要 |
FIELD: electric measurement technology; determining condition of power-plant insulation and predicting its life expectancy. SUBSTANCE: method involves additional measurement of frequency response tgδ(W) and frequency Wof maximum of dielectric power factor before ageing, as well as dependence of difference between frequency Wand current valueof maximum of dielectric power factor for reference insulationaged due to expiration of its service life, measurement of tgδ of inspected power plant insulation at frequency W″, determination of frequency W′ corresponding to tgδ on above-mentioned characteristic tgδ(W); condition of insulation is determined by frequency difference W-W″ andof maximum of tgδ for reference insulation aged due to expiration of its service life; additionally introduced in device are storage unit, frequency difference measuring unit for source of superimposed as current and frequency corresponding to dielectric power factor on frequency response tgδ(W), temperature sensor, functional converter, insulation residual life measuring unit; frequency difference measuring unit is connected through its first input to output of tgδ measuring unit, through its second input, to storage unit, and through output, to input of functional converter whose second input is connected to temperature sensor output and its output, to first input of residual life measuring unit whose second input is supplied with reference voltage Vand its output is connected to input of final circuits. EFFECT: improved validity of insulation condition evaluation and its service life prediction. |
