Design, Prototyping and Testing of a Rotating Electrical Machine With Linear Geometry for Shipboard Applications

Abstract

Conventional rotating electrical machines are characterized by stator and rotor structures featuring a cylindrical geometry around the shaft rotational axis. Although advantageous for mechanical reasons, the cylindrical geometry results in overall machine shapes and dimensions that may be unsuitable for installation. This particularly occurs in shipboard applications, where electric motors and generators are subject to stringent room constraints and need to be fit in unusually shaped compartments. This paper presents the development and test of a dual-shaft rotating permanent-magnet electric machine prototype having a linear structure that facilitates its onboard use for such applications as electric propulsion and rudder actuation. In fact, the proposed machine topology has overall dimensions which can be adjusted to fit the space available for installation. The operating concept and the detailed electromechanical design of the machine are first described. Then the manufacturing and factory test of the prototype under inverter supply are illustrated. Finally, the validation of the prototype as a boat propulsion variable-speed inverter-fed motor is presented. It is proved that, despite of its highly non-conventional electromechanical design, the machine can be effectively fed from a general-purpose inverter for permanent magnet motors.

Segmented Hairpin Topology for Reduced Losses at High-Frequency Operations

“…Nowadays, transport electrification is one of the most viable solutions to reduce emissions and meet fuel economy requirements. Hybrid and pure electric vehicles are being developed for all transport applications [1], [2], [3], [4]. Besides these requirements, power density, efficiency and reliability are also objectives of primary importance to achieve when designing a more electric vehicle.…”