Method of capacitance current measuring
Tiecheng Lu · Dianli zidonghua shebei · 2005
A method to measure the capacitance current at the secondary winding of PT is introduced.Constant voltages with same amplitude but different frequencies are injected into the open-delta of PT to get its grounding capacitance current i0 and then to calculate the capacitance current of network.The selected frequencies of injected voltage influence the measurement accuracy,which are 45 Hz,48 Hz and 52 Hz in this paper.A simulative test is carried out with a field 10 kV PT,voltages of different amplitudes and frequencies are injected into the open-delta of PT with different concen-trated capacitances instead of grounding capacitance.The calculative results from measured data show its feasibility.