"Active flux" based wide speed range motion sensorless control of permanent magnet synchronous machines

Abstract

The main goal of the thesis is to offer new solutions for the sensorless control system of the permanent magnet synchronous machines in a wide speed range. A novel concept called “active flux” is introduced for unified motion sensorless AC drives and particularity, in this thesis for the IPMSM and PM-RSM. The key element of a sensorless controlled drive is the estimation of the rotor position and speed. Different estimation methods exist in the literature, but achieving low speed operation was possible by now only with the signal injection method. Based on the “active flux”, this estimation is now achieved much simpler and with less computation effort than using signal injection mehod. To show the versality of the novel active flux concept, experimental results from two different experimental platforms, containing two PMSMs prototypes (the IPMSM and PM-RSM) and with four proposed control methods (vector control, direct torque control and two equivalent proposed strategies for wide speed range ) are presented and discussed. Consequently, once the performance of the position sensorless control drive is presented, the position sensored one is not included in the thesis.