高压直流接地极单极运行对变压器脉动冲击.pdf

周加斌，等
2022 52 8 ELECTRIC DRIVE ng electrode from bipolar to unipolar earth mode was discussed. Based on the principle of field-circuit
coupling，the DC magnetic bias co-simulation model of transformer was established and analyzed the action
mechanism of grounding electrode unipolar earth mode on AC power network and transformer excitation
characteristics. Through analysis of the simulation model，the results show that when the DC grounding pole from
bipolar to unipolar earth mode，magnetic bias current flowing through the AC power grid is pulsating DC current that
varies with time，its instrusion into transformer winding causes the excitation current of transformer winding
fluctuation change，with the increase of pulse DC amplitude，between transformer excitation current peak and valley
difference also gradually increased. When the operation mode of DC grounding electrode is adjusted，the simulation
model can provide certain babis for the level monitoring of AC power network DC magnetic bias level and the
evaluation of transformer excitation characteristics.