Comparative study on tuning methods for variable speed drives

The aim of this study is to analyse the tuning and compare the performance of four well known speed control algorithms used in variable speed drives: the proportional-integral, integral-proportional, two degrees of freedom proportional-integral and state feedback motion controllers. The study compares pole-placement-based tuning with command-tracking frequency response function (FRF) based tuning. The assessment is focused on the resulting command tracking, mechanical impedance, and sensitivity FRFs. Simulation and experimental results confirm that tuning the controllers with the command-tracking FRF approach leads to an increased disturbance rejection capability of the speed loop.