THE INDIRECT INDUCTION MOTOR TORQUE METHOD DEVELOPMENT BY USING STM32F4 MICROCONTROLLER

Abstract

To measure the dynamic characteristics of an induction motor, such as the angular velocity,
the phase current of the stator winding, the phase voltage dependence in time, the STM32F4 microcontroller
firmware was used, such as the capture-comparison mode of the built-in timer channels and the analog to
digital converter in the multichannel scanning mode. The algorithm for adjusting the microcontroller timer
for signals capture and adjusting the built-in analog-to-digital converter for performing analog values such
as current and voltage is presented. The developed software for collecting measured data from various
channels is described and considered in this article. The scheme of connections of the necessary equipment
for carrying out the experiment is presented. The angular velocity, stator current and asynchronous motor
voltage data arrays obtained from the STM32F4 microcontroller are presented. The method of asynchronous
electrical motor torque determination on the friction torque example as the most difficultly determined from
the point of view of high-precision measurements of the obtained small values of idle current values, net
power, and also value of idling speed is very close to synchronous motor angular velocity. The obtained
friction torque values were compared with the similar results obtained from the results of another proposed
graph-analytical technique. The voltage sensor rectified signal converting into a sinusoidal signal algorithm
for further use is developed and implemented. The ratios for calculating and analyzing the asynchronous
friction torque calculated by different paths are given. The experimental data arrays obtained from the
STM32F4 microcontroller are presented in the form of Microsoft Excel charts.