Review and Analysis of Coaxial Magnetic Gear Pole Pair Count Selection Effects

Magnetic gears perform the same function as mechanical gears using magnetic fields instead of interlocking teeth. A review of the design processes used in the literature demonstrates that a critical design parameter, pole pair count, is often given inadequate consideration. In addition to reviewing...

Full description

Saved in:
Bibliographic Details
Published in:IEEE journal of emerging and selected topics in power electronics 2022-04, Vol.10 (2), p.1813-1822
Main Authors: Praslicka, Bryton, Gardner, Matthew C., Johnson, Matthew, Toliyat, Hamid A.
Format: Article
Language:English
Subjects:
Cogging factor (<italic xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">CT )
Design parameters
efficiency
Electromagnetic losses
finite element analysis (FEA)
Gear ratios
Integers
magnetic forces
magnetic gear
Magnetic gears
Modulation
Modulators
Optimization
permanent magnet (PM)
pole pairs
Power electronics
Prototypes
radial flux
ripple factor
Ripples
Rotors
Symmetry
Torque
torque density
Torque measurement
torque ripple
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Magnetic gears perform the same function as mechanical gears using magnetic fields instead of interlocking teeth. A review of the design processes used in the literature demonstrates that a critical design parameter, pole pair count, is often given inadequate consideration. In addition to reviewing the existing prototypes, this article uses a parametric simulation study to analyze the impacts of pole pair counts on gear performance and illustrate how the optimal pole counts vary with gear ratio and various design parameters. This article also introduces new ripple factors, which better correlate with torque ripple than the cogging factor ( C_{T} ) used in previous articles, and illustrates why designs with noninteger gear ratios tend to have much smaller torque ripples than designs with integer gear ratios. While selecting the pole counts to minimize symmetry can reduce torque ripple, designs without any symmetry are shown to experience unbalanced magnetic forces on each rotor. Thus, it is recommended to select pole counts that result in an even number of modulators but not an integer gear ratio. This article also reveals that for a fixed gear ratio, a nontrivial optimum pole count minimizes the electromagnetic losses.
ISSN:2168-6777
2168-6785
DOI:10.1109/JESTPE.2021.3053544