Gas monitoring system and respective method
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.
1 . A gas monitoring system comprising:
a gas-insulated switchgear comprising 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, the statistical step and/or change detection comprising identifying an expected range based on past sensor measurements and checking if a current sensor measurement is outside of the expected range, and
in response to a determination that a jump and/or a change occurred:
reset a leakage rate calculation of the insulating gas in the chamber or
remove the jump and/or change by applying an offset to the sensor measurements.
2 . The gas monitoring system according to claim 1 , whereby the computer unit is adapted to:
decide on either of resetting the leakage rate calculation or removing the jump and/or change depending on, in case jump is determined, on a height of the jump and/or a direction of the jump and/or on an additional measurement signal indicative to a status of the gas-insulated switchgear, and/or whereby
the computer unit is adapted to:
calculate a leakage rate of the insulating gas in the chamber.
3 . The gas monitoring system according to claim 1 , whereby a jump and/or a change is characterized by a measurement that is ≥1.5, 2.0 or 2.5 of a standard deviation of the measurements of the last one hour, last two hours, last one day or last two days.
4 . The gas monitoring system according to claim 1 , whereby the statistical change detection comprises sequentially discounting autoregression time series modelling.
5 . The gas monitoring system according to claim 1 , whereby the physical property of the insulating gas is indicative of a density of the insulating gas in the chamber.
6 . The gas monitoring system according to claim 1 , whereby the gas-insulated switchgear comprises a voltage transformer.
7 . The gas monitoring system according to claim 1 , whereby the insulating gas is SF6.
8 . A method for detecting a jump and/or a change in a gas-insulated switchgear comprising a chamber filled with an insulating gas surrounding a high or medium voltage component, comprising:
Measuring, by a sensor, a physical property of the insulating gas in the respective chamber over time, and
Performing 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 comprises identifying an expected range based on past sensor measurements and checking if a current sensor measurement is outside of the expected range.
9 . The method according to claim 8 , whereby, if a jump and/or a change occurred, the method comprises:
Resetting a leakage rate calculation of the insulating gas in the chamber or
Removing the jump and/or change by applying an offset to the sensor measurements.
10 . The method according to claim 9 , whereby the method comprises:
Deciding on either of resetting the leakage rate calculation or removing the jump and/or change depending on, in case jump is determined, on a height of the jump and/or a direction of the jump and/or on an additional measurement signal indicative to a status of the gas-insulated switchgear.
11 . The method according to claim 8 , the method comprises:
Calculating a leakage rate of the insulating gas in the chamber.
12 . The method according to claim 8 , whereby a jump and/or a change is characterized by a measurement that is ≥1.5, 2.0 or 2.5 of a standard deviation of the measurements of the last one hour, last two hours, last one day or last two days.
13 . The method according to claim 8 , whereby the statistical change detection comprises sequentially discounting autoregression time series modelling.
14 . The method according to claim 8 , whereby the physical property of the insulating gas is indicative of a density of the insulating gas in the chamber.
15 . A gas monitoring system comprising:
a gas-insulated switchgear comprising a chamber filled with an insulating gas surrounding a high or medium voltage component,
a sensor operatively connected to the chamber and configured to generate a plurality of measurements of a physical property of the insulating gas in the chamber at a plurality of times, and
a microprocessor configured to:
perform, on the plurality of sensor measurements, a detection operation comprising at least one of a statistical step detection for determining whether a jump has occurred and a statistical change detection for determining whether a change has occurred, the detection operation comprising identifying an expected range based on a subset of the plurality of sensor measurements and determining whether a current sensor measurement of the plurality of sensor measurements is outside of the expected range, and
in response to a determination that a jump and/or a change occurred:
reset a leakage rate calculation of the insulating gas in the chamber or
remove the jump and/or change by applying an offset to the plurality of sensor measurements.
16 . The gas monitoring system according to claim 15 , whereby the microprocessor is further configured to:
determine whether to reset the leakage rate calculation or remove the jump and/or change based on, in response to a determination that a jump has occurred, a height of the jump and/or a direction of the jump and/or on an additional measurement signal indicative to a status of the gas-insulated switch gear.
17 . The gas monitoring system according to claim 15 , whereby the microprocessor is further configured to calculate a leakage rate of the insulating gas in the chamber.
18 . The gas monitoring system according to claim 15 , wherein a jump and/or a change is determined based on a measurement that is ≥1.5, 2.0 or 2.5 of a standard deviation of the measurements of a previous predetermined time period.
19 . The gas monitoring system according to claim 1 , whereby the statistical change detection comprises sequentially discounting autoregression time series modelling.
20 . The gas monitoring system according to claim 1 , whereby the physical property of the insulating gas is indicative of a density of the insulating gas in the chamber.