Bin Feng, Yao Chuanfei, Feng Jixiang, Liang Fangwei, Sun Qiuqin
School of Physics and Electronic Science, Changsha University of Science and Technology, Changsha, 410114, China.
State Key Laboratory of Power Systems, Tsinghua University, Beijing, 100084, China.
Sci Rep. 2025 May 26;15(1):18378. doi: 10.1038/s41598-025-01904-4.
Corona discharge is a typical discharge in gas-insulated equipment; however, the correlation between microscopic discharge process and macroscopic electromagnetic (EM) wave signals excited by discharge remains unclear. Therefore, this study innovatively employs the space current pulse as a bridge to reveal their relationship through the multi-scale simulation. First, the needle-plate discharge process in SF gas is simulated based on a fluid dynamics model. Then, the effects of voltage, temperature, and the curvature of needle tip on the space current pulse are investigated. Lastly, the current pulses generated under varying conditions serve as excitation sources, and the finite-difference time-domain (FDTD) method is utilized to establish correlations between the corona discharge stages and discharge conditions and the amplitude-frequency characteristics of excited EM waves. The simulation results indicate that in the rising and falling stages of current pulse, the spectral energy is predominantly concentrated in the high frequency band (2.3-3.0 GHz) of the ultra-high-frequency (UHF) range, whereas the spectral energy constitutes the highest proportion within the mid-high frequency band (1.6-2.3 GHz) in the stabilization stage. As voltage, temperature, or the curvature of needle tip increases, there is a corresponding rise in the proportion of EM energy within both the low frequency band (0.2-0.9 GHz) and the mid-low frequency band (0.9-1.6 GHz), as well as in the mid-high frequency band; conversely, the proportion of energy within the high frequency band diminishes. The proposed multi-scale simulation method provides a novel way to obtain the characteristics of EM waves induced by partial discharge (PD) in gas.
电晕放电是气体绝缘设备中的一种典型放电现象；然而，微观放电过程与放电激发的宏观电磁（EM）波信号之间的相关性仍不明确。因此，本研究创新性地采用空间电流脉冲作为桥梁，通过多尺度模拟来揭示它们之间的关系。首先，基于流体动力学模型模拟了SF气体中的针 - 板放电过程。然后，研究了电压、温度和针尖曲率对空间电流脉冲的影响。最后，将不同条件下产生的电流脉冲作为激励源，利用时域有限差分（FDTD）方法建立电晕放电阶段、放电条件与激发EM波的幅频特性之间的相关性。模拟结果表明，在电流脉冲的上升和下降阶段，频谱能量主要集中在超高频（UHF）范围的高频带（2.3 - 3.0 GHz），而在稳定阶段，频谱能量在中高频带（1.6 - 2.3 GHz）中占比最高。随着电压、温度或针尖曲率的增加，低频带（0.2 - 0.9 GHz）、中低频带（0.9 - 1.6 GHz）以及中高频带内的EM能量比例相应增加；相反，高频带内的能量比例减小。所提出的多尺度模拟方法为获取气体中局部放电（PD）感应的EM波特性提供了一种新途径。
