A gas monitoring system includes a gas-insulated switchgear including a chamber filled with an insulating gas surrounding a high or medium voltage component, a sensor operatively connected to the chamber and adapted to measure a physical property of the insulating gas in the chamber over time, and a computer unit adapted to perform on the sensor measurements a statistical step detection for determining if a jump has occurred and/or a statistical change detection for determining if a change has occurred, whereby the statistical step and/or change detection includes identifying an expected range based on past sensor measurements and checking if a current sensor measurement is outside of the expected range.

A sensor system for determining physical variables of a switchgear assembly having a sensor connection, which is designed for connection to the switchgear assembly, within which a humidity sensor and/or a pressure sensor and a light sensor for detecting light flashes are arranged. A switchgear assembly is provided that is filled, in particular, with a protective gas, comprising at least one such sensor system.

A gas leak detection device includes a learning section, which has a correlation between a gas temperature inside gas pressure containers and a surface temperature of the gas pressure containers in a learning period corresponding to a current value flowing in the conductor, to make database, and a diagnosis section, which extracts a gas temperature corresponding to the measured current value and the surface temperature from the learning section in a diagnosis period, corrects a gas pressure value corresponding to an arbitrary surface temperature to a gas pressure value of a reference temperature using the extracted gas temperature, and detects a leak of the insulating gas based on the corrected gas pressure value.

A sulfur hexafluoride (SF6) insulated circuit breaker system has a tank constructed to hold a quantity of SF6; a circuit breaker having contacts insulated by the SF6; a heater operative to supply heat to the SF6; and a thermal capacitor in conductive engagement with the tank, and operative to store heat energy and constructed to conduct the heat energy to the SF6 in the tank. A thermal energy storage system for a sulfur hexafluoride (SF6) insulated circuit breaker system having a tank storing a quantity of SF6 includes a thermal capacitor operative to store heat energy and constructed to engage the tank and conduct the heat energy to the SF6 in the tank.

A method for determining a quantity of a gas contained in a tank of a gas insulated switchgear. The method includes during a calibration phase: (i) acquiring a plurality of successive sets of calibration samples comprising a gas pressure, a gas temperature and an ambient temperature, (ii) for each set of calibration samples, determining a corrected gas temperature from a model and (iii) determining a gas quantity contained in the tank from a gas state equation and from the determined corrected gas temperature. The method further includes during a measurement phase: (v) determining a corrected gas temperature from the model and from an acquired gas temperature, gas pressure and ambient temperature, and (vi) determining the quantity from the gas state equation and from the determined corrected gas temperature.

The invention relates to an electric switching device (1), comprising at least one switching-device pole filled with insulating gas and a monitoring apparatus (14). The monitoring apparatus (14) comprises a density monitor (15) and a housing part (16), wherein a gas chamber (17) is contained in the housing part (16), which gas chamber is connected to the switching-device pole and to the density monitor (15) and can be connected to a testing device for the density monitor (15), and wherein the housing part (16) contains a shut-off element (20), which can be actuated into an open position and into a closed position. The actuation of the shut-off element (20) is independent of the connection of the gas chamber (17) to the testing device.

A sulfur hexafluoride (SF6) insulated circuit breaker system has a tank constructed to hold a quantity of SF6; a circuit breaker having contacts insulated by the SF6; a heater operative to supply heat to the SF6; and a thermal capacitor in conductive engagement with the tank, and operative to store heat energy and constructed to conduct the heat energy to the SF6 in the tank. A thermal energy storage system for a sulfur hexafluoride (SF6) insulated circuit breaker system having a tank storing a quantity of SF6 includes a thermal capacitor operative to store heat energy and constructed to engage the tank and conduct the heat energy to the SF6 in the tank.

Mechanical, electronic, algorithmic, and computer network facets are combined to create a highly integrated advanced sensor that monitors the gas density, state-of-repair, and events associated with switchgear. Measurements of gas pressure, atmospheric pressure, gas temperature, are used with models of the non-ideal behavior of a particular gas to realistically estimate gas density. A hierarchical system of signal processing optimizes measurements working within high-frequency, real-time, short-term, medium-term, diurnal, long-term, and historical timeframes and overcomes measurement errors present in real-world applications. The time at which a condition such as gas density will reach a particular level is calculated. Events such as threshold attainments and switchgear operation are detected. A large memory stores all raw data values allowing flexible re-processing and verification at any future time. Instantaneous as well as logged information is communicated in convenient formats over a selected digital network. An embedded web server provides a familiar graphical user interface.

A gas leak detection device includes a learning section, which has a correlation between a gas temperature inside gas pressure containers and a surface temperature of the gas pressure containers in a learning period corresponding to a current value flowing in the conductor, to make database, and a diagnosis section, which extracts a gas temperature corresponding to the measured current value and the surface temperature from the learning section in a diagnosis period, corrects a gas pressure value corresponding to an arbitrary surface temperature to a gas pressure value of a reference temperature using the extracted gas temperature, and detects a leak of the insulating gas based on the corrected gas pressure value.

A gas monitoring system includes a gas-insulated switchgear including a chamber filled with an insulating gas surrounding a high or medium voltage component, a sensor operatively connected to the chamber and adapted to measure a physical property of the insulating gas in the chamber over time, and a computer unit adapted to perform on the sensor measurements a statistical step detection for determining if a jump has occurred and/or a statistical change detection for determining if a change has occurred, whereby the statistical step and/or change detection includes identifying an expected range based on past sensor measurements and checking if a current sensor measurement is outside of the expected range.