【摘要】 针对地磁感应电流(GIC)导致电网变压器出现的异常问题，研究GIC畸变对变压器产生的电磁干扰与机械-声传播影响。首先分析了GIC入侵电网的关键路径与原理，根据实测数据研究GIC变化规律。提出考虑GIC畸变的变压器干扰传播模型，将电磁-机械-声路径划分为电磁干扰域与振动-噪声传播域的耦合。然后仿真分析不同干扰场景下变压器多场物理特征信息，总结电流畸变率、畸变时刻对变压器电流、磁通、振动、噪声的干扰与传播影响规律。最后搭建动模实验平台，测量变压器的多场物理参数，并与仿真对比，验证所提模型与结论的正确性。结果表明，在GIC畸变的“拐点”处，变压器振动噪声异常加剧；“拐点”越接近电流最大值，该问题越严重。研究GIC畸变率Δk与振动噪声参数的映射关系，当Δk>3时，GIC干扰已危害变压器的结构稳定性，为电网变压器的态势感知与辨识提供依据。更多还原

【Abstract】 Aiming at the abnormal problem of power grid transformer caused by geomagnetic induced current(GIC), the influence of GIC distortion on electromagnetic interference and mechanical-acoustic propagation of transformer was studied. Firstly, the critical path and principle of GIC invading power grid were analyzed, and the change law of GIC was studied according to the measured data. A transformer interference propagation model considering GIC distortion was proposed, and the electromagnetic-mechanical-acoustic path was divided into the coupling of electromagnetic interference domain and vibration-noise propagation domain. Then, the multi-field characteristic information of the transformer under different interference scenarios was simulated and analyzed, and the influence of current distortion rate and distortion time on transformer current, magnetic flux, vibration and noise was summarized. Finally, a dynamic simulation experiment platform was built to measure the multi-field parameters of the transformer, and was compared with the simulation to verify the correctness of the proposed model and conclusion. The results show that the abnormal vibration and noise of the transformer are aggravated at the “inflection point” of GIC distortion. The closer the “inflection point” is to the maximum current, the more serious the potential damage to the electrical components will be. The mapping relationship between GIC distortion rate Δk and vibration noise parameters was studied. When Δk>3, GIC interference has endangered the structural stability of transformer, which provides a basis for situation awareness and identification of power grid transformer.更多还原