A Novel Linear Permanent Magnet Vernier Machine With Consequent-Pole Permanent Magnets and Halbach Permanent Magnet Arrays

The Vernier permanent-magnet (VPM) machines are recently attracting more attention for utilisation in low-speed, high-torque applications including renewable energy conversion systems, electric vehicles and elevators. Although, the VPM machines present interesting advantages, they suffer from lower power factor (PF) in comparison to the conventional permanent-magnet (PM) drives. In this study, a novel structure of the VPM machine with dual-stator and consequent-pole (CP) rotor topology is proposed with enhanced PF. The objectives in this new structure are achieving higher torque density per PM volume, higher efficiency, simpler and more robust installation of PM pieces, lower cogging torque and simpler rotor core laminations compared to the previously proposed VPM structures with reasonably improved PF. The low PF issue of VPM machines is analysed in details and the novel CP-VPM geometry is designed to diminish this drawback. Then analytical relations are derived based on the magnetic-equivalent-circuit for evaluating the flux density distribution, induced back electromotive force, magnetising reactance and PF. The effectiveness of the novel structure in enhancing the operating features is validated using analytical and 2D-FE simulation results. Finally, it is concluded that the performance of the optimally designed structure can be enhanced reasonably so that to consider it as a good choice for direct-drive applications.

Section: Operation Principles Of Cp-vpm Machinementioning

confidence: 99%

“…However, choosing this ratio as 0.625, i.e. 1/1.6, leads to elimination of spatial harmonics with higher orders according to (6). Thus, some of undesirable spatial harmonics of air-gap magnetic field are omitted and the differential leakage inductance will be reduced.…”

Section: Operation Principles Of Cp-vpm Machinementioning

confidence: 99%

Dual‐stator consequent‐pole Vernier PM motor with improved power factor

Gorginpour

2019

“…13). This has been reported in both linear and rotary PMVMs [65][66][67], in which the Halbach PM array helps in intensifying the main flux path as well as reducing slot leakage flux while the consequent-pole rotor introduces a doubly-salient structure. Therefore, either the stator teeth or the rotor poles can be modulation poles.…”

Section: Evolution Of Topologiesmentioning

confidence: 82%

Permanent magnet vernier machine: a review

El-Refaie

2019

Permanent magnet vernier machines (PMVMs) gained a lot of interest over the past couple of decades. This is mainly due to their high torque density enabled by the magnetic gearing effect. This study will provide a thorough review of recent advances in PMVMs. This review will cover the principle of operation and nature of magnetic gearing in PMVMs, and a better understanding of novel PMVM topologies using different winding configuration as well as different modulation poles and rotor structures. Detailed discussions on the choice of gear ratio, slot-pole combinations, design optimisation and role of advanced materials in PMVMs will be presented. This will provide an update on the current state-of-the art as well as future areas of research. Furthermore, the power factor issue, fault tolerance as well as cost reduction will be discussed highlighting the gap between the current state-of-the art and what is needed in practical applications.

“…Recently, there are some investigations on a new type of linear primary PM vernier (LPPMV) machines, thanks to its mechanical integrity, high-thrust, low-speed, and low cogging torque characteristics [16,17]. Regarding the mentioned WEC type, there are some research on the linear vernier machines (LVMs) as the WEC, where the PM is commonly used in their structure, as well as the various structures are proposed [16,[18][19][20][21][22][23][24][25][26][27]. LVMs modelling is an important issue, which has been investigated by researchers.…”

Section: Introductionmentioning

confidence: 99%

Linear vernier machine wave converter modelling and analysis by MEC

Naderi

Sharouni

Moradzadeh

2020

This study presents a novel technique for modelling of linear primary permanent-magnet (PM) vernier machine wave converter based on an improved magnetic-equivalent-circuit (MEC) method. Saturation effect is considered by a new method, where the B-H curve fitting is performed using a novel non-linear function. The machine properties such as the number of PMs, number of slots, magnets size, and all other machine parameters can be selected arbitrarily in the proposed model. The machine structure is considered by 12 individual zones. Each of the flux tubes in core and air gaps is modelled by a non-linear reluctance, and the machine performances in both transient and steady-state conditions are studied. Various machine properties such as magnets size and winding configuration are analysed and the dynamic behaviour is compared in various cases. Comparison to finite-element method (FEM) shows the effectiveness and accuracy of the proposed MEC method and its much shorter processing time compared with FEM.