As the world moves towards a cleaner and greener future, electrical machines for various industrial purposes and transport applications have gained a lot of attention. Permanent magnet synchronous machines (PMSMs) are usually the solution for electric vehicle (EV) applications thanks to their high efficiency, compactness and high-power density. On the downside, although the price of rare-earth materials has recovered close to historical levels, concerns still remain and the questions on the environmental sustainability of these materials have also been raised, which has encouraged the researchers to consider rare-earth-free machines.The switched reluctance machine (SRM) is one of the competitive alternatives, thanks to the simple and robust construction, high reliability and inherent fault tolerance capability. However, it has a bad reputation when it comes to torque ripple and acoustic noise. And the highly nonlinear characteristic brings much difficulty to routine design purposes and machine optimisation.Therefore, some of the above mentioned problems are addressed - a torque-ripple-reduction, reliable and low-cost system of SRMs is presented in this thesis. Firstly from the modelling point of view, a combined magnetic equivalent circuit (MEC) and finite element (FE) model of SRMs is developed for fast characterization the nonlinear behavior. Secondly from the control point of view, various torque-ripple reduction techniques are implemented and compared. Moreover, a minimal current sensing strategy with enhanced fault-detection capability is proposed and validated experimentally. It requires two current sensors, to replace the phase current sensors, with no additional devices for fault detection, to achieve a more compact and low-cost drive. Finally from the reliability point of view, an interturn short-circuit fault detection method and a rotor position estimation approach are investigated and validated experimentally, which leads to a more reliable system. / Doctorat en Sciences de l'ingénieur et technologie / info:eu-repo/semantics/nonPublished

This thesis is focused on the design of vector control of interior permanent magnet synchronous motors. The first part of this work deals with vector control transformations and mathematical modelling of synchronous motors. Furthermore, algorithms of sensorless control are discussed, especially HF injection sensorless methods. One of these methods was used for torque and speed control. Problem of phase delay caused by filters and it’s compensation is also discused. One of the HF injection sensorless method was implemented on both motors. The results of simulations in MATLAB/Simulink and tests of real motors on dSpace are included.

The thesis is focused on the issue of sensorless vector control of a synchronous motor with permanent magnets in the low-speed range. In the first part, there is a brief description of the synchronous motor and the necessary transformations for the application of vector control. This is followed by the overview of sensorless methods for position estimation by injecting a high-frequency harmonic signal. The practical part is devoted to the implementation of a control algorithm to develop kit STM32NUCLEO-L476RG, which is preceded by the identification of all engine parameters. As part of the implementation, a structure including current, speed and position control was designed. The functionality and robustness of the settings have been successfully tested due to the different inertia and load.