Design of an Electric Machine Integrated with Trans-Rotary Magnetic Gear

Abstract

Design aspects of the trans-rotary magnetic gear (TROMAG) integrated rotary machine are discussed in this paper, with particular focus on optimizing system cost and weight. Analytical models are used for design of the TROMAG. Optimal designs of the rotary machine are found by using a populationbased genetic algorithm and two-dimensional finite-element analysis and thermal considerations. Weight, volume, and cost of the resultant system are then compared with the Pareto-optimal set of a permanent magnet linear tubular machine that is designed for the same force and speed specification. It is shown in this paper that, for high-force low-speed reciprocating motion applications, an electromechanical motion system consisting of a TROMAG and a rotary electric machine can far surpass a conventional direct drive linear machine in terms of weight, volume, and initial and operating cost.Index Terms-Finite-element analysis (FEA), linear permanent magnet (PM) machines, magnetic gear, trans-rotary magnetic gear.

Magnetic equivalent circuit modelling of coaxial magnetic gears considering non‐linear magnetising curve

“…One of the most important specifications of MGs is their ability to transfer torque. Various kinds of MGs are introduced in the literature such as trans-rotary axial MGs [7,8], and linear MGs [9] that each kind has advantages and limitations. Some structures such as spur worm type [10,11], type [12,13], and bevel type [10,14,15] have been proposed, but they have low torque transmission capability because of engaging a few numbers of magnet poles [14][15][16].…”

Axial-Flux PM Disk Generator With Magnetic Gear for Oceanic Wave Energy Harvesting

“…Concentric planetary magnetic gears have been explored, where attempts have been made for making them industrially feasible, by applying winding function theory (WFT) [13], and by using passive methods of oscillation repression [14]. Different design aspects of trans-rotary magnetic gear (TROMAG) were analyzed in [15] and [16], which were further integrated with electrical machines to inspect the viability of their application [17], [18]. Substantial studies were performed on coaxial radial magnetic gears in [19]- [22].…”

Analysis, design and experimental verification of a coaxial magnetic gear using stationary permanent‐magnet ring

“…It is well known that the mechanical gears can achieve a high torque density but always suffer from some inherent problems, which actually causes a higher use-cost. In contrast, the magnetic gear (MG) offers significant advantages of reduced noise, minimum vibration, free from maintenance, improved reliability, and inherent overload protection [1], thus being promising alternative to the mechanical gears in the applications of electric vehicles [2], wind power generation [3], and low-speed high-torque reciprocating applications [4]. In [5], the development status of MGs, including the converted and field-modulated topologies, has been reviewed.…”