The article describes digital and analogue methods for linearising the conversion function of thermoresistive transducers, with a detailed analysis of analogue methods. Analogue methods for linearising bridge circuits and measurement circuits based on passing a reference current through a resistance temperature detector (RTD) are considered. Linearisation of bridge circuits is based on the formation of the compensatingsupply voltage of the bridge circuit, which depends on the change in the measured temperature. When using the measurement method based on passing a reference current through an RTD, nonlinearity compensation is achieved by changing the conversion coefficient of the measuring signal or passing an additional current through the RTD, which linearly depends on the value of the RTD’s voltage change (measured temperature value). When passing an additional compensation current through the RTD, the nonlinearity error is not grater than0.1°C in the range of 0...800°C, and the schematic diagram of the measuring transducer contains a minimum number of elements, which allows to increase its reliability. In general, the choice of a linearisation method depends on the requirements for accuracy, operation rateand resource limitations of the measuring system.

The article presents a method of implementing a functionally integrated device for temperature measurement, which allows for controlled heating of the primary temperature transducer, measurement of the heating temperature as well as the temperature and differential temperature of the investigated and reference samples. The heating speed is regulated by the selection of the frequency and duration of the control impulses. To measure the temperature and temperature difference, it is proposed to use measuring currents of different polarity, which make it possible to simplify the device design. The methods of linearisation of the conversion function of primary temperature transducer based on the formation of compensating currents in given measurement ranges have been investigated. The conducted studies showed that the temperature measurement error does not exceed 0.11°C and 0.005°C in the control heating mode and in the temperature measurement mode, respectively. The temperature measurement error of the investigated and reference samples and the differential temperature measurement error does not exceed ±0.003°C and 0.001°C, respectively.

УДК: 621.382

Розглянуто проблематику побудови засобів магнітної діагностики плазми в термоядерних реакторах наступного покоління. На основі проведеного аналізу запропоновано новий підхід до реалізації функціонально інтегрованих пристроїв вимірювання магнітного поля у таких реакторах, новизною яких є поєднання сенсорів Холла та індукційних котушок. Такий підхід забезпечує періодичне in-situ самокалібрування сигнальних трактів, а відтак підвищення точності пристроїв магнітної діагностики в жорстких умовах експлуатації. Подано результати розроблення апаратно-програмної системи, основними компонентами якої є 3Dзонд, що поєднує сенсори Холла та індукційні котушки, аналоговий фронт-енд сигнального
перетворення та програмні засоби подальшого цифрового перетворення сигналів. Відповідно до концепції злиття даних подано структуру та послідовність калібрування функціонально інтегрованих пристроїв магнітної діагностики термоядерних реакторів, а також програмне забезпечення для аналізу шумових стохастичних процесів вимірювальних кіл на основі дисперсій Аллана.
Ключові слова: сенсор; магнітне поле; інтегрування сенсорів; злиття даних; калібрування.

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