• IEEEFellow-AnnetteMütze• Einrichtung eines Christian Doppler Labors

für Bürstenlose Antriebe für Pumpen- undLüfteranwendungen(www.cdg.ac.at)

• OGEPreisdesOVE(ÖsterreichischeGesell-schaft fürEnergietechnik imÖsterreichischenVerband für Elektrotechnik und Informations-technik-MadeleineBali

• Stipendium des Hans List Fonds 2016 -ChristianPaar

• ICEM2016BestPosterPresentationAward-ThomasTanzer

• ITEC2016BestPaperPrize-HeinrichEickhoff• APEC 2016 Best Presentation Award -

AlexanderConnaughton• Zahlreiche Veröffentlichungen in renommier-

tenFachzeitschriften,insbesondereIEEE

Auszeichnungen2016

EAM

InstitutfürElektrischeAntriebstechnikundMaschinen

Das InstitutEineKurzdarstellung

Technische Universität GrazInstitut für Elektrische Antriebstechnik und MaschinenInffeldgasse18/1,8010Graz,AustriaT:+43(0)316873-7241,helga.liebmann@tugraz.at► www.tugraz.at/institute/eam/

3178 IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 51, NO. 4, JULY/AUGUST 2015

Design Constraints of Small Single-Phase PermanentMagnet Brushless DC Drives for Fan Applications

Stephan Dunkl, Annette Muetze, Senior Member, IEEE, and Gerhard Schoener

Abstract—Permanent magnet brushless dc (BLDC) machinesare widely used due to various advantages such as high efficiencyand high torque density, and therefore compactness as well as longexpected lifetime. All of these benefits are of major interest whendesigning a drive for a small fan application of a few watts. Thispaper presents the design investigations of a small single-phaseBLDC motor for such an application. Notably, it discusses differ-ent constraints which arise during the design process and whichmay be of special relevance due to the particular given power leveland application.

Index Terms—Dynamic simulation, multidomain model,single-phase brushless dc (BLDC) fan.

I. INTRODUCTION

BRUSHLESS dc (BLDC) motors have gained popularitydue to their high efficiency, silent operation, compact

form, reliability, and low maintenance [1], [2]. Permanentmagnet (PM) BLDC motors use PMs for the rotor field exci-tation and an electronically commutated winding on the stator.Notably, with the use of rare earth magnets, these motors canhave higher efficiency and be more compact when comparedto induction motors and mechanically commutated dc motors.Single-phase PM BLDC motors, although less efficient com-pared to their three-phase counterparts, are cost-effective andeasy to mass manufacture. They are used in applications whichrequire output power ranging from a fraction of a watt to a fewtens of watts [3], [4].

The target application was a small fan drive motor. To meetthe specifications and because fan applications do not need highstarting torques, an outer rotor single-phase BLDC appeared tobe a good and cost-effective solution. Furthermore, it ensuressimple motor construction and minimal electronic part count[5]–[7].

This paper discusses the design of a single-phase BLDCdrive and presents different design constraints that arose. Fur-

Manuscript received September 3, 2014; revised January 26, 2015; acceptedJanuary 27, 2015. Date of publication February 24, 2015; date of currentversion July 15, 2015. Paper 2014-IDC-0599.R1, presented at the 2013 IEEEEnergy Conversion Congress and Exposition, Denver, CO, USA, September16–20, and approved for publication in the IEEE TRANSACTIONS ON INDUS-TRY APPLICATIONS by the Industrial Drives Committee of the IEEE IndustryApplications Society.

S. Dunkl and A. Muetze are with Graz University of Technology, 8010 Graz,Austria (e-mail: stephan.dunkl@tugraz.at; muetze@tugraz.at).

G. Schoener is with MSG Mechatronic Systems GmbH, 8551 Wies, Austria(e-mail: gerhard.schoener@mechatronic-systems.at).

Color versions of one or more of the figures in this paper are available onlineat http://ieeexplore.ieee.org.

Digital Object Identifier 10.1109/TIA.2015.2406856

Fig. 1. Stator and drive circuit of a single-phase outer rotor BLDC fan motor.

thermore, it discusses the relationship between different designparameters and the final motor performance. With this aimin mind, three different parameter studies will be presented.These parameter studies will vary the height and material ofthe magnets used, the number of turns of the winding, andthe dimensions of the motor. While much of the analysis mayappear to follow classical machine theory, aspects such asmanufacturability and particular motor dimensions may requirespecial treatment due to these machines’ small sizes (Fig. 1).In the context of today’s energy debate in which the energyconversion efficiencies of small energy converters have alsobecome very important (not only their cost), we consider suchdiscussion to be of renewed interest.

This paper is divided into six sections. Sections II–V discussthe specifications and challenges of the motor design and howthese were solved. In the main Section VI, different designconstraints and relations between the design parameter and themotor performance are presented. The theoretical studies drawnfrom a multidomain model have been validated experimentally.Moreover, the experimental results of a prototype drive areprovided.

II. DESIGN SPECIFICATION

The small fan drive to be designed should provide an outputpower of Pout = 1 W at an operating speed of nr = 5000 r/minat the motor shaft. Furthermore, the specifications of the smallfan drive include some fairly restrictive operating conditions:

1) outer diameter of 30 mm;2) guaranteed performance for a dc supply voltage of Udc ∈

{8 V . . . 16 V};3) maximum current of Imax = 1 A.

0093-9994 © 2015 IEEE. Personal use is permitted, but republication/redistribution requires IEEE permission.See http://www.ieee.org/publications_standards/publications/rights/index.html for more information.

April2017

Das Institut beschäftigt sich mit FragestellungenausdenBereichenderelektrischenAntriebstechnik,elektrischen Maschinen und Stromrichtertechnik,besonders im Hinblick auf deren Einsatz in einemoptimiertenGesamtsystem.

Daraus ergeben sich Projekte, die Analyse,Dimensionierung&Optimierung,Untersuchung ver-schiedener Topologien, sowie Fragen zur System-integrationzumInhalthaben.

Der größte Teil der laufenden Projekte findet inZusammenarbeitmitderIndustriestatt.

• ElektrischeAntriebstechnik• ElektrischeMaschinen• Leistungselektronik• Stromrichtertechnik• Antriebsregelung• Zu diesen Themengebieten gehörende experi-

mentelleArbeiten

2016

• Magneticmaterialdegradationduetodifferentcuttingtechniquesanditsmodelingforelectricmachinedesign

• ControlaspectsofsingleandthreephasePMdrivesinfractionalhorsepowerapplications

• Thermal design of electric traction machinesintegratedinhybridelectricvehicles

2015

• Thermal modelling of water-cooled electricmachinesofsometensofkilowatts

• A high efficiency modular wide input voltagerangepowersupply

• Design of IM and SynRM machine basedactuators for elevated temperature environ-ments

• Motorentwicklung für kleine Leistungen (einige10W bis 100W, Massenproduktion; mehrereProjekte)

• Einfluss materialwissenschaftlicher Frage-stellungen auf Maschinen- und Antriebsaus-legung

• Leistungselektronische Systeme (einige W biseinigekW;mehrereProjekte)

• Anwendungsoptimierte Regelung z. B. verlust-minimal

• SensorloseRegelung(keinePositionssensoren)• Thermische Simulationen und Motordimensio-

nierungfürElektrotraktionsantriebe(einige10kWLeistung)

• GroßgeneratorenamFrequenzumrichter(einige10bis100MW)

• HVDCDC – Hochspannungs-DC-DC-Wandler(ET&ITKooperation)

Betätigungsfelder AusgewählteProjekte Dissertationen

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