METHOD FOR TEMPERATURE ERROR COMPENSATION OF THERMISTORS, DEVICE FOR METHOD IMPLEMENTATION Russian patent published in 2020 - IPC G01R17/10 G01K7/08 G01K1/20 

FIELD: measurement.

SUBSTANCE: invention relates to measurement equipment, in particular to measurements of electrical resistances of thermal resistors, and can be used in instrument engineering, in temperature measurements, including during calibration and calibration of thermistors: resistance thermometers, thermistors, posistors, and their use for temperature measurements, higher accuracy of temperature measurement by compensation of temperature error of thermal resistors. This is solved by the fact that in the thermistors temperature measurement method, which consists in limitation of the current passing through the thermistor, by adding an additional thermally independent resistor to the measuring circuit, the power supplied to the additional thermally independent resistor is maintained constant regardless of change of resistance of the thermistor in the range of measured temperatures. In order to perform the task in the above method, the permissible value of the power supplied to the additional thermally independent resistor is set according to the expression , where is the set value of the current flowing in the measurement circuit; ΔT^Perm. is permissible error of temperature measurement by thermistor due to its heating by flowing measurement current; δ_T is thermistor thermal dissipation coefficient; R^*₁ is maximum value of resistance of thermistor at boundaries of range of measured temperatures, for thermistor - lower boundary of range of measured temperatures, for resistance thermometer and posistor - upper boundary of range of measured temperatures; R₂ is resistance value of additional thermally independent resistor. Besides, in order to implement the disclosed method, a measurement transducer is proposed for measuring temperature in the form of a voltage divider comprising a power supply connected in series, thermistor, additional thermally independent resistor, voltage at the thermistor is the output of the converter, where the source of supply is a source of stabilized current. In order to implement the disclosed method, a measurement transducer is also provided for measuring temperature in the form of a voltage divider, comprising a series-connected power supply, a thermistor, an additional thermally independent resistor, voltage across the thermistor is the output of the converter, where power supply source is a controlled power supply source, control inputs of which are connected to outputs of additional thermally independent resistor.

EFFECT: technical result when implementing the declared group of solutions is compensation for temperature error of temperature measurement by thermoresistor due to heating (self-heating) of thermistor (resistance thermometer, thermistor, posistor) with flowing measurement current.

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