Analysis of a gas dissolved in an insulating medium of a high-voltage device

An analysis device for analysing a gas dissolved in an insulating medium of a high-voltage device, the analysis device comprising:

• a separator configured to transfer the dissolved gas into a gas phase to obtain an analysis gas mixture;
• an analysis sensor configured to generate a sensor signal output signal as a function of a composition of the analysis gas mixture, wherein the composition of the analysis gas mixture corresponds to a concentration of a gas converted into a gas phase in the analysis gas mixture;
• a pump configured to transport the analysis gas mixture from the separator to the analysis sensor;
• and
• an evaluator, which is configured:
• to determine a first intermediate value based on the sensor signal, which depends on the concentration of the gas converted into the gas phase in the analysis gas mixture, and a disturbance value and a second disturbance value based on a first regression model, where the first intermediate value is a concentration of the gas converted into the gas phase influenced by the first disturbance value and the second disturbance value, and the first disturbance value comprises a temperature and a moisture content of an environment of the analysis sensor and the second disturbance value comprise a flow velocity of the insulating medium;
• to determine a second intermediate value based on the first intermediate value and at least one specific value of the analysis device using a second regression model, wherein the at least one specific value of the analysis device comprises a property of the analysis sensor or the analysis device;
• and
• to determine a value for a concentration of the dissolved gas in the insulating medium based on the second intermediate value.

An analysis device for analysing a gas dissolved in an insulating medium of a high-voltage device, the analysis device comprising:

• a separator configured to transfer the dissolved gas into a gas phase to obtain an analysis gas mixture;
• an analysis sensor configured to generate a sensor signal output signal as a function of a composition of the analysis gas mixture;
• a pump configured to transport the analysis gas mixture from the separator to the analysis sensor;
• and
• an evaluator, which is configured:
• to determine a first intermediate value based on the sensor signal and at least one disturbance value;
• to determine a second intermediate value based on the first intermediate value and at least one specific value of the analysis device;
• and
• to determine a value for a concentration of the dissolved gas in the insulating medium based on the second intermediate value,
• wherein the evaluator:
• comprises a processor and a measuring device configured to determine a temperature of the processor;
• and
• is configured to determine a temperature in an environment of the analysis sensor based on the temperature of the processor.

A method for determining a concentration of a gas that is dissolved in a liquid insulating medium for a transformer, a choke, or a tap-changer, the method comprising:

• receiving an analysis gas mixture at an analysis sensor, the analysis gas mixture comprising a portion of the gas that was dissolved in the insulating medium after having been converted into a gas phase by passing through a semipermeable membrane of an analysis device that is in fluid communication with the liquid insulating medium comprising the dissolved gas;
• generating a sensor signal as an output signal of the analysis sensor as a function of a composition of the analysis gas mixture, wherein the composition of the analysis gas mixture corresponds to the concentration of the gas converted into the gas phase in the analysis gas mixture;
• determining a first intermediate value based on the sensor signal, which depends on the concentration of the gas converted into the gas phase in the analysis gas mixture, and a first disturbance value and a second disturbance value based on a first regression model, where the first intermediate value is a concentration of the gas converted into the gas phase influenced by the first disturbance value and the second disturbance value, and the first disturbance value comprises a temperature and a moisture content of an environment of the analysis sensor and the second disturbance value comprise a flow velocity of the insulating medium;
• determining a second intermediate value based on the first intermediate value and at least one specific value of the analysis device using a second regression model, wherein the at least one specific value of the analysis device comprises a property of the analysis sensor or the analysis device;
• and
• determining a value for the concentration of the gas that is dissolved in the liquid insulating medium based on the second intermediate value.