Active Suppression and Elimination of PT Ferromagnetic Resonance Using a Damping Resistor Parallel Model
In ungrounded neutral systems,due to the unfavorable combination of ground capacitance and electromagnetic voltage transformer inductance,ferromagnetic resonance often occurs when the system voltage undergoes large disturb-ances,resulting in PT damage.To this end,a method of suppressing and eliminating PT ferromagnetic resonance by using a damping resistor parallel model is proposed.The damping resistor is parallelly connected to the model at the PT open tri-angle,and a large damping resistor is used to achieve early suppression of high-frequency resonance.By analyzing the PT primary zero sequence current and open triangle zero sequence voltage,single-phase grounding fault and resonance are dis-tinguished,and the damping small resistor is controlled to eliminate resonance.A simulation on model established by MATLAB/Simulink verifies the feasibility of the proposed method.
NETL
NSTL
万方数据
