Design of a Variable Phase-Pole Induction Machine for Electric Vehicle Applications

The electrification of the transport sector requires significant research in electrical machines and drives to fulfil the application constraints. High torque demands at low speed and high-speed requirements at relatively low torque are posing challenges for the design of efficient machines with a compact and sustainable design. The ability to reach very high speeds makes a variable phase-pole machine attractive for electric traction. Moreover, their dimensions compared to conventional machines has not been sufficiently investigated. This work describes the design and control of a variable phase-pole induction machine with distributed windings for electric vehicle applications. The induction machine is designed to work in two switchable configurations: three-phase/six-pole, and nine-phase/two-pole. The control model is developed based on Harmonic Plane Decomposition. The proposed machine is compared to a conventional induction machine with non-switchable phase-pole configuration, showing a reduction in size for the same coverage of the torque-speed map.