METHOD AND ELECTRONIC DEVICE FOR THE CONTROL OF TEMPERATURE OF A METALLIC FILAMENT BY INDIRECT MEASUREMENT

摘要

The invention relates to a method and an electronic device for the control of temperature of a metallic filament, by indirect measurement. According to the invention, the method for the temperature control of a metallic filament consists in determining the filament resistance based on the measured values of the voltage and intensity of the current on the filament, comparing the said resistance to a reference value and bringing it to the reference value corresponding to a desired temperature, according to a characteristic of resistance variation with the temperature. The device, as claimed by the invention, comprises a voltage step down converter () in synchronous configuration, with two commutation elements and a numerical control circuit represented by a microcontroller (), where the control of the two commutation elements is achieved by means of a pulse-width repetition ratio modulated signal, where the duration of the positive plateau is computed by a microcontroller () based on an algorithm and applied to the commutation elements via a driver (), the converter load being represented by a metallic filament () the voltage of which is measured with a transducer () and is transmitted to the microcontroller () via an analogue-to-digital converter (), the current passing through the filament () being measured with a current transducer () which transmits the same to the microcontroller () using another channel of the analogue-to-digital transducer, a bidirectional communication channel being established between the microcontroller () and a computer () on which a user application is installed.