FIELD: electrical engineering. SUBSTANCE: method is related to facilities for compensation for capacitive currents of single-phase contact to ground in electrical networks of 6.0-35.0 kV with insulated neutral, it can be employed for more accurate measurement of capacitance of network phases to ground for subsequent resonance adjustment of arc control reactors. Proposed method measuring capacitance consists in formation of artificial potential on neutral of network by insertion of source of non-commercial frequency into neutral and in measurement of voltage of neutral displacement across open winding of voltage transformer. Generator of variable frequency is utilized as source of non-commercial frequency. Smoothly changing frequency of generator one finds resonance frequency of arc control reactor and capacitance of network. After it conduction of reactor on resonance frequency is calculated as ratio of current of reactor to voltage in neutral, then required value of conduction of reactor on frequency of 50 Hz is obtained with the aid of relation of two frequencies: of 50 Hz commercial frequency to found resonance frequency. In correspondence with second version method measuring capacitance lies in formation of artificial potential on neutral of network by insertion of source of non-commercial frequency into neutral. Generator of variable frequency is employed as source of non-commercial frequency. Resonance frequency of arc control reactor and capacitance of network are found by smooth change of frequency of generator. After it value of capacitance of network is calculated as value inversely proportional to square of found resonance frequency with known fixed initial induction of reactor on commercial frequency. EFFECT: increased accuracy of measurement of capacitance of network. 2 cl, 1 dwg
Authors
Dates
2001-07-20—Published
2000-01-25—Filed