Various embodiments of the teachings herein include methods for determining the state of an electrical switchgear assembly. The method may include: measuring an electric current and a voltage dropped across the switchgear assembly; ascertaining a time interval of an arc occurring during a switching operation; comparing the ascertained time interval to a reference value specific to the switchgear assembly; measuring a voltage profile during the time interval; and comparing the voltage profile with a reference voltage profile. The time interval begins when the value of the measured voltage exceeds a first threshold value. The time interval ends when the value of the current intensity falls below a second threshold value.

Fault-indicator assemblies that can each be mounted externally to a corresponding electronic device to provide a visual indication that an internal fault has occurred within the electronic device. A fault-indicator assembly of the present disclosure can be configured for electrical devices such as electrical power transformers, capacitors, and reactors, among others. Some embodiments can be configured to connect to existing orifices of a conventionally manufactured electronic device, such as an orifice for a conventional pressure-relief valve. Such embodiments can be deployed without any modifications to the electrical devices and can be readily retrofitted to existing electrical devices. In some embodiments, a pressure-relief valve can be integrated with the fault-indicator assembly to provide both fault-indication functionality and pressure-relief functionality in the same assembly.

A method for detecting partial discharges of an electrical operating device, wherein electromagnetic signals are captured at different positions of the operating device in a decentralized manner by a plurality of sensor apparatuses, where a sinusoidal phase progression is centrally determined for a voltage by a voltage-measuring assembly, and at least one phase point characterizing the phase progression is provided, and the electromagnetic signals are each provided with a time stamp, and a partial discharge signal is determined in each of the electromagnetic signals, and the at least one time stamp of the characterizing phase point and the time stamps of the partial discharge signals are taken into consideration by an evaluation assembly in a superposition of the sinusoidal phase progression with the partial discharge signals. An assembly detects partial discharges of an electrical operating device by the method.

A gas monitoring system includes a gas-insulated switchgear, wherein the gas-insulated switch gear has at least two separated chambers which are filled with an insulating gas surrounding high or medium voltage components. A first sensor is connected to the first chamber and a second sensor is connected to the second chamber, both sensors adapted to measure a physical property of the insulating gas in their respective chambers over time. A computer unit is adapted to calculate from the two sensor measurements a leakage rate of the insulating gas in one of the two chambers using an adaptive filter, in particular a Wiener filter.

A partial discharge (PD) detection apparatus for gas-insulated equipment includes a photon collector, an optical splitter, a first photoelectric conversion module, an ultraviolet fluorescent crystal, a second photoelectric conversion module, and a signal processing module, where the ultraviolet fluorescent crystal is configured to convert a second optical radiation signal into an optical radiation signal of an ultraviolet fluorescence band, and the signal processing module is configured to calculate first apparent intensity based on a first voltage signal output by the first photoelectric conversion module, calculate second apparent intensity based on a second voltage signal output by the second photoelectric conversion module, and determine discharge intensity of the optical radiation based on a ratio of the second apparent intensity to the first apparent intensity. Technical solutions of the present disclosure are not affected by an unknown distance between a discharge position and a detection point.

The invention relates to a high-voltage transformer which is configured as a toroidal transformer. The high-voltage transformer has a magnetizable core (310) and a high-voltage winding (330) and a low-voltage winding (320) around the magnetizable core (310). The high-voltage winding (330) is embodied at least partially as a pilgrim step winding.

Fault-indicator assemblies that can each be mounted externally to a corresponding electronic device to provide a visual indication that an internal fault has occurred within the electronic device. A fault-indicator assembly of the present disclosure can be configured for electrical devices such as electrical power transformers, capacitors, and reactors, among others. Some embodiments can be configured to connect to existing orifices of a conventionally manufactured electronic device, such as an orifice for a conventional pressure-relief valve. Such embodiments can be deployed without any modifications to the electrical devices and can be readily retrofitted to existing electrical devices. In some embodiments, a pressure-relief valve can be integrated with the fault-indicator assembly to provide both fault-indication functionality and pressure-relief functionality in the same assembly.

A high-voltage bushing has an insulator, which contains an insulating gas and an insulating solid, and an inner conductor which is led through the insulator. A mounting flange is employed for the mounting of the high-voltage bushing on a wall. A sensor, which is arranged on the mounting flange and is configured for the detection of at least one reaction product of the insulating gas and/or of the insulating solid. A corresponding method monitors an operating state of the high-voltage bushing.

The present disclosure relates to a coaxial lead structure and method for radiating a GIS partial discharge UHF signal outward. The structure includes a GIS cavity, a circular hole provided on the GIS cavity, a medium cylinder provided at the circular hole and sealing the circular hole, a thin cylindrical metal lead that extends into and is fixed to the medium cylinder, and a ground lead connected to the thin cylindrical metal lead. According to the present disclosure, a relatively strong signal may be obtained outside a coaxial lead structure, and detection of a partial discharge UHF signal at this position may increase the detection sensitivity by one time compared with the detection methods of built-in and external disc insulators.

An approach to detecting partial discharge events involves retrofitting an electrical system to include a capacitive sensor configured to capacitively sense partial discharge events of a component of the electrical system. The capacitive sensor has a first electrical conductor that forms a first terminal of the capacitive sensor, a second electrical conductor that forms a second terminal of the capacitive sensor, and a dielectric that separates the first electrical conductor and the second electrical conductor. The capacitive sensor generates an electrical sensor signal at an output of the capacitive sensor in response to the partial discharge event. The electrical sensor signal is converted to an optical signal and the optical signal is processed to detect an occurrence of the partial discharge event.