Analyzing the Accuracy of Measurement by a Shunt Current Sensor with a Delta-Sigma Converter in Electric Drives
«NRU «MPEI», Алексей Сергеевич Анучин, Dimid Surnin, Maksim Lashkevich, Aleksandеr A. ZHARKOV, Vidim N. OSTRIROV · Elektrichestvo · 2018
This article considers the accuracy of current measurement using a shunt sensor in an adjustable speed drive using delta-sigma modulation. Current measurement with resistive shunts is becoming increasingly common due to the appearance of galvanically isolated delta-sigma microchips (modulators). This solution is cheaper than the closed-loop Hall-effect current sensors and has already been successfully used in some industrial electric drives. The accuracy of the obtained result after demodulation in the microcontroller is investigated in the article. By modeling, the maximum error was obtained as a function from the oversampling ratio, the type of digital filter and the relative value of the input sigal.