Fast Evaluation of Self-Sensing Capability of Synchronous Machines

Convergence region and estimation error of high frequency injection sensorless control strictly depend on the selected synchronous machine and on the actual operating point. An accurate knowledge of the motor parameters is required to compute the self-sensing capability range. The aim of this article is to show a fast solution to identify the convergence region based on incremental parameters approximation with less experimental measurements than the conventional approach. The proposed method to reconstruct the motor convergence region is fully offline. It requires few samples of the inverse incremental inductances, which are processed through some math and a simple fitting procedure. The method is validated through experimental measurements for two different types of synchronous motors for a sensorless drive application.