Axial-flux modular permanent-magnet generator with a toroidal winding for wind-turbine applications

Abstract

NOTICEThis report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or any agency thereof. Abstract -Permanent-magnet generators have been used for wind turbines for many years. Many small wind turbine manufacturers use direct-drive permanent-magnet generators. For wind turbine generators, the design philosophy must cover the following characteristics: low cost, light weight, low speed, high torque, and variable speed generation. The generator is easy to manufacture and the design can be scaled up for a larger size without major retooling.

On the Optimal Pole Width for Direct Drive Linear Wave Power Generators Using Ferrite Magnets

“…Already in the 1960ies, development was made on ferrite generators [2], and Spooner was rather active in the 1990ies [3][4][5]. Even ferrite magnet transverse flux machines have been proposed [6]. Although some studies indicate that it in general does not pay off to replace neodymium magnets with ferrite magnets [7], it strongly depends on the neodymium price, and ferrites may be an alternative in situations where the larger weight of the machine is of little importance or even advantageous, provided that the actual cost of neodymium is sufficiently high so that the extra iron and winding needed is paid by the reduction in magnet cost.…”

Génératrice à aimants permanents à flux axial à grand diamètre avec entrefer immergé. éléments de conception et analyse des performances pour un cahier des charges d’hydrolienne

“…Le projet CoRMaT de l"Université Strathclyde à Glasgow peut également être cité : une machine à aimants permanent à flux axial à double rotor est utilisée pour la possibilité d"intégration de deux hélices en fonctionnement contrarotatif (Clarke et al, 2010). Dans (Muljadi et al, 1999 ;Brisset et al,2006), les auteurs proposent également des machines à flux axial, principalement pour des considérations industrielles comme la modularité (fractionnement de la puissance statorique), la facilité d"insertion des bobines (réduction des coûts de main-d"oeuvre pour la réalisation du bobinage). De manière générale, d"après (Chalmers et al, 1999 ;Dubois et al, 2000) les machines à flux axial poly entrefer peuvent avoir une meilleure compacité, un rendement et une capacité de fonctionnement à haute vitesse supérieurs aux machines à aimants permanents à flux radial.…”

Design and Performance Analysis of Coreless Axial-Flux Permanent-Magnet Generator for Small Wind Turbines

“…Power generation from the wind primarily converts energy from the wind into mechanical energy through the rotating blades of a wind turbine, and uses the converted mechanical energy to drive a generator to produce electrical energy. The overall performance of a wind power generation system is thus very dependent on the conversion efficiency of its power generator [1,2].…”