Analytical Methods for Minimizing Cogging Torque in Permanent-Magnet Machines

Zhu, Li; Jiang, Shan; Zhu, Z. Q.; Chan, C. C.

doi:10.1109/tmag.2008.2011363

Cited by 328 publications

(43 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The 15 poles and 16 slots combination gives very low values of cogging torque because of the high value of the least common multiple of the poles and slots [28]. To make a better presentation for the cogging torque, a machine of 70 poles and 60 slots is used in this subsection only.…”

Section: Cogging Torque Comparisonmentioning

confidence: 99%

A Simple and Efficient Quasi-3D Magnetic Equivalent Circuit for Surface Axial Flux Permanent Magnet Synchronous Machines

Hemeida

Lehikoinen

Rasilo

et al. 2019

IEEE Trans. Ind. Electron.

View full text Add to dashboard Cite

This paper presents a simple and efficient magnetic equivalent circuit (MEC) model for surface axial flux permanent magnet synchronous machines. The MEC model is used to solve all the electromagnetic properties of the machine including the no load, full load voltages, cogging torque, torque ripple and stator iron core losses. Moreover, this approach can be extended for all surface permanent magnet synchronous machines. The main novelty of this approach is the development of a static system, which accounts for the rotation. The model takes into account the rotor rotation via time dependent permanent magnet magnetization sources. The static system matrix facilitates a very fast solving. In addition, to take into account the 3D effect, a multi-slicing of the machine in the radial direction is done. This boosts the simulation time to only 60 seconds for 6 slices and 50 time steps including the non-linear behaviour of the stator elements with a great accuracy. Additionally, the number of elements in the MEC can be adjusted to reduce the computational time. This model is verified by means of 3D and 2D multi slice finite element (FE) models. In addition, experimental validations are also provided at the end. Index Terms-Analytical modeling, Axial flux permanent magnet synchronous machines (AFPMSM), Cogging torque, Magnetic equivalent circuit (MEC), Surface permanent magnet synchronous machines (SPMSM), Torque ripple. Peter Sergeant received the M.Sc. degree in electromechanical engineering and the Ph.D. degree in engineering sciences from

show abstract

Section: Cogging Torque Comparisonmentioning

confidence: 99%

A Simple and Efficient Quasi-3D Magnetic Equivalent Circuit for Surface Axial Flux Permanent Magnet Synchronous Machines

Hemeida

Lehikoinen

Rasilo

et al. 2019

IEEE Trans. Ind. Electron.

View full text Add to dashboard Cite

show abstract

“…The interaction between the Stator excitation source (PM, excitation coil) and rotor pole of machine at no-load is called cogging torque. The magnetic circuit consists of an existing PM and coil having co-energy, the total co-energy is formulated as [20,21].…”

Section: Cogging Torquementioning

confidence: 99%

Modular Rotor Single Phase Field Excited Flux Switching Machine with Non-Overlapped Windings

Rahman

Khan

et al. 2019

Energies

View full text Add to dashboard Cite

This paper aims to propose and compare three new structures of single-phase field excited flux switching machine for pedestal fan application. Conventional six-slot/three-pole salient rotor design has better performance in terms of torque, whilst also having a higher back-EMF and unbalanced electromagnetic forces. Due to the alignment position of the rotor pole with stator teeth, the salient rotor design could not generate torque (called dead zone torque). A new structure having sub-part rotor design has the capability to eliminate dead zone torque. Both the conventional eight-slot/four-pole sub-part rotor design and six-slot/three-pole salient rotor design have an overlapped winding arrangement between armature coil and field excitation coil that depicts high copper losses as well as results in increased size of motor. Additionally, a field excited flux switching machine with a salient structure of the rotor has high flux strength in the stator-core that has considerable impact on high iron losses. Therefore, a novel topology in terms of modular rotor of single-phase field excited flux switching machine with eight-slot/six-pole configuration is proposed, which enable non-overlap arrangement between armature coil and FEC winding that facilitates reduction in the copper losses. The proposed modular rotor design acquires reduced iron losses as well as reduced active rotor mass comparatively to conventional rotor design. It is very persuasive to analyze the range of speed for these rotors to avoid cracks and deformation, the maximum tensile strength (can be measured with principal stress in research) of the rotor analysis is conducted using JMAG. A deterministic optimization technique is implemented to enhance the electromagnetic performance of eight-slot/six-pole modular rotor design. The electromagnetic performance of the conventional sub-part rotor design, doubly salient rotor design, and proposed novel-modular rotor design is analyzed by 3D-finite element analysis (3D-FEA), including flux linkage, flux distribution, flux strength, back-EMF, cogging torque, torque characteristics, iron losses, and efficiency.

show abstract

“…Concerning the cogging torque, many methods have been used such as the lateral force [30], complex permeance [31,32] and energy [33,34]. In PM machines, calculating and minimizing the cogging torque is classically evaluated using either the virtual work or Maxwell stress tensor methods.…”

Section: Electromagnetic and Cogging Torquesmentioning

confidence: 99%

An Analytical Subdomain Model of Torque Dense Halbach Array Motors

et al. 2018

View full text Add to dashboard Cite

A two-dimensional mathematical model estimating the torque of a Halbach Array surface permanent magnet (SPM) motor with a non-overlapping winding layout is developed. The magnetic field domain for the two-dimensional (2-D) motor model is divided into five regions: slots, slot openings, air gap, rotor magnets and rotor back iron. Applying the separation of variable method, an expression of magnetic vector potential distribution can be represented as Fourier series. By considering the interface and boundary conditions connecting the proposed regions, the Fourier series constants are determined. The proposed model offers a computationally efficient approach to analyze SPM motor designs including those having a Halbach Array. Since the tooth-tip and slots parameters are included in the model, the electromagnetic performance of an SPM motor, described using the cogging torque, back-EMF and electromagnetic torque, can be calculated as function of the slots and tooth-tips effects. The proposed analytical predictions are compared with results obtained from finite-element analysis. Finally, a performance comparison between a conventional and Halbach Array SPM motor is performed.

show abstract

Analytical Methods for Minimizing Cogging Torque in Permanent-Magnet Machines

Cited by 328 publications

References 25 publications

A Simple and Efficient Quasi-3D Magnetic Equivalent Circuit for Surface Axial Flux Permanent Magnet Synchronous Machines

A Simple and Efficient Quasi-3D Magnetic Equivalent Circuit for Surface Axial Flux Permanent Magnet Synchronous Machines

Modular Rotor Single Phase Field Excited Flux Switching Machine with Non-Overlapped Windings

An Analytical Subdomain Model of Torque Dense Halbach Array Motors

Contact Info

Product

Resources

About