可控磁飽和電抗器在中壓電網接地系統中運行狀況的建模與仿真

馬淋淋 梁艷萍

摘 要：針對10-35 kV的中壓電網經弧線圈接地運行方式中，消弧線圈的補償度不能根據電容電流大小連續平滑調節的問題，提出了一種基于可控磁飽和電抗器的新型消弧線圈。并以一臺額定電壓為10 kV的可控磁飽和電抗器為研究對象，基于磁路分段的原理，充分考慮直交流繞組共同作用情況下磁路和電路的非線性問題，建立了消弧線圈的“磁路-電路耦合仿真模型”，并在系統模型中進行了仿真實驗。對實驗波形的計算結果表明，該消弧線圈可在電網發生單相接地故障時，能夠根據單相接地電容電流的大小平滑調整補償度，使接地電流得到有效抑制，保證接地電弧順利自熄，提高系統的供電可靠性，并給出了諧波的抑制策略。

關鍵詞：可控磁飽和電抗器；消弧線圈；單相接地故障；中性點；諧振

DOI：10.15938/j.emc.（編輯填寫）

中圖分類號：TM 474 文獻標志碼：A 文章編號：1007 -449X（2018）00-0000-00（編輯填寫）

Abstract： A new arc suppression coil based on magnetically controlled saturated reactor is proposed aimed to solve compensation degree of arc suppression coil cannot be continuously adjusted smoothly according to the capacitance current at 10-35kV Medium-voltage power network. Taking a magnetically controlled saturated reactor with rated voltage of 10kV as the research object， based on principle of magnetic circuit segmentation， the coupling simulation model of magnetic circuit and circuit of arc suppression coil is established considering the nonlinear problem of magnetic circuit and circuit which is under the combined action of AC winding and DC winding. The calculation results of the experimental waveform show that the suppression coil can adjust compensation degree smoothly according to the size of the single-phase grounding capacitor current when single phase earth fault occurs in power grid. Therefore the grounding current can be effectively suppressed， the grounding arc can be smoothly extinguished， and the power supply reliability of the system can be improved， and the harmonic suppression strategy is given.

Keywords： controllable magnetic saturation reactor， arc-extinguishing coil， single phase ground fault； neutral point； resonance