發(fā)布時間：2019-03-16 21:09

【摘要】：詳細論述了直流系統(tǒng)單極運行及磁暴引發(fā)的變壓器直流偏磁的異同點,進而探討了地磁感應電流(GIC)的等效源建模問題。通過PSCAD/EMTDC平臺搭建了計及變壓器偏磁效應的雙機系統(tǒng)仿真模型,對線路事故過負荷進行了仿真研究,分析評估線路距離保護耐受GIC的能力。仿真結果表明GIC通過中性點接地變壓器侵入電力系統(tǒng)后,可能造成變壓器鐵心不對稱飽和,從而使測量阻抗發(fā)生周期性波動。距離保護Ⅲ段作為下級變壓器的遠后備保護,在線路事故過負荷造成負荷轉移的情況下,其動作可靠性降低,可能受GIC擾動而發(fā)生誤動。
[Abstract]:The similarities and differences of DC bias caused by magnetic storm and monopole operation of DC system are discussed in detail. Furthermore, the equivalent source modeling of geomagnetic induced current (GIC) is discussed. The simulation model of two-machine system considering the magnetic bias effect of transformer is set up by PSCAD/EMTDC platform. The over-load of line accident is simulated and the ability of line distance protection and tolerance to GIC is analyzed and evaluated. The simulation results show that when GIC invades the power system through the neutral grounding transformer, it may cause asymmetrical saturation of the core of the transformer, thus causing periodic fluctuation of the measuring impedance. As the remote backup protection of the lower transformer, the operation reliability of the distance protection section 鈪，

本文編號：2441965