Accurate calculation of short-circuit electromagnetic force is crucial for both mechanical strength check and the optimal design of gas-insulated transmission lines (GIL). Since the full 3D numerical simulation method is highly time-consuming, a novel lightweight 2D multi-slice electromagnetic field-circuit coupled method for computing transient electromagnetic force is proposed, where appropriate port voltage degrees of freedom (DoFs) are introduced for the solid GIL conductor terminals. When the transient magnetic field equations are combined with the constraint equations of circuit part, including nodal voltage and loop current DoFs, a direct field-circuit coupling scheme is thus derived. The proposed method can simultaneously consider the effect of interphase-shunts and ground wires, as well as the skin effect and proximity effect. It can accurately capture the transient electromagnetic characteristics of GIL spanning from several to tens of kilometers under different short-circuit conditions. The transient electromagnetic forces, as well as the induced voltages and currents of the enclosure, are analysed by the proposed method for both single-phase and three-phase enclosed GIL under various short-circuit conditions. The proposed method has the advantages of high accuracy and lightweight computational cost, and thus it is also suitable for conducting important simulation tasks such as mechanical strength checks during the design optimisation phase of long-distance GIL.

中文翻译：

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一种新型多层电磁场-电路耦合长距离气体绝缘输电线路暂态计算方法

准确计算短路电磁力对于气体绝缘输电线路（GIL）的机械强度校核和优化设计至关重要。由于全3D数值模拟方法非常耗时，因此提出了一种计算瞬态电磁力的新型轻量级2D多层电磁场电路耦合方法，其中为固体GIL引入了适当的端口电压自由度（DoF）导体端子。当瞬态磁场方程与电路部分的约束方程（包括节点电压和环路电流DoF）相结合时，就可以导出直接场电路耦合方案。该方法可以同时考虑相间分流器和地线的影响，以及集肤效应和邻近效应。它可以准确捕捉不同短路条件下GIL跨越数公里至数十公里的瞬态电磁特性。通过所提出的方法，对各种短路条件下的单相和三相封闭式 GIL 的瞬态电磁力以及外壳的感应电压和电流进行了分析。该方法具有精度高、计算成本低的优点，因此也适合在长距离GIL设计优化阶段进行机械强度校核等重要仿真任务。