2025 lEEE International Conference on Predictive Control of Electrical Drives and Power Electronics (PRECEDE 2025)

Main subject of this tutorial is the design and control strategies for linear machines (LMs). Starting with a brief introduction to the development and categories of such machines, their potential applications will be exposed in the tutorial, including MAGLEV vehicles, linear metro, compressor, etc.

Three types of LMs, linear induction machine (LIM), linear oscillatory machine (LOM), and linear doubly-fed machine (LDFM), will be introduced in details. First, design criteria and performance analysis methods of LIM will be specifically exposed, emphasizing the main differences with the classic rotary induction machine, caused by the presence of large air-gaps, half-filled slots as well as the end effects. Advanced control techniques specifically employed for LIM, like loss minimization control, model predictive control, etc., will be presented. Second, a new type of double stator permanent magnet switched flux LOM will be introduced, with emphasis on the design of parallel magnetic circuit and the principle of how the LOM utilizes the working magnetic field to simultaneously generate permanent magnet thrust and high positioning force. Afterwards, the resonant frequency tracking control and sensorless control strategies specifically adopted to LOM will be introduced. Moreover, for the LDFM, its special structure and basic operating principle will be described, especially the unique direct-coupled trait. The asymmetry of three-phase winding will be analyzed quantitatively. Based on the analysis of static and dynamic end effect, the equivalent circuit model considering end effect will be presented, with which a simplified filed oriented control and static end effect compensation strategy in connection with dc power supply will be further introduced. Finally, conclusions are given out, of which some emerging directions and techniques of LMs and drives are prospected.