The switching operations of circuit breakers and disconnectors in substations can generate very fast transients, including transient earth voltage rise and intense electromagnetic radiation, causing severe disturbance of on-site electronic devices in substations and seriously affecting the development of smart power equipment. The power supply of an on-site electronic device provides a path along which the disturbance couples with the device. In this article, we investigated the coupling mechanism and measures to suppress this disturbance. We found that, for most on-site electronic devices, their power supply includes a power line that connects the exterior and interior of the shielding box, greatly reducing the shielding effectiveness and inducing disturbance from the outside to the inside. This article proposes a shielding–crossing isolation transformer as the power supply of which the primary winding is outside and the secondary winding is inside of the shielding box, without a power line across the shielding box. This arrangement proved to deliver the high performance in terms of eliminating disturbance from the power supply. This article provides an understanding of the mechanism according to which the electromagnetic disturbance couples through the power supply. A method to determine the electromagnetic compatibility of on-site electronic devices in a substation is also proposed.

中文翻译：

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变电站现场电子设备电源端口电磁干扰耦合特性及其抑制

变电站断路器和隔离开关的投切操作会产生极快的瞬态，包括瞬态地电压升高和强烈的电磁辐射，对变电站现场电子设备造成严重干扰，严重影响智能电力设备的发展。现场电子设备的电源提供了干扰与设备耦合的路径。在本文中，我们研究了耦合机制和抑制这种干扰的措施。我们发现，对于大多数现场电子设备来说，它们的电源包括一根连接屏蔽盒外部和内部的电源线，大大降低了屏蔽效果，并引起了从外部到内部的干扰。本文提出了一种初级绕组在屏蔽箱内，次级绕组在屏蔽箱内的电源，采用屏蔽-交叉隔离变压器，电源线不穿过屏蔽箱。事实证明，这种安排在消除电源干扰方面提供了高性能。本文介绍了电磁干扰通过电源耦合的机制。还提出了一种确定变电站现场电子设备电磁兼容性的方法。事实证明，这种安排在消除电源干扰方面提供了高性能。本文介绍了电磁干扰通过电源耦合的机制。还提出了一种确定变电站现场电子设备电磁兼容性的方法。事实证明，这种安排在消除电源干扰方面提供了高性能。本文介绍了电磁干扰通过电源耦合的机制。还提出了一种确定变电站现场电子设备电磁兼容性的方法。