Analysis of a two phase brushless motor used in a CPU cooling fan

Author

Fussell, Barry K.

Author_Institution

Dept. of Mech. Eng., New Hampshire Univ., Durham, NH, USA

fYear

2001

fDate

2001

Firstpage

379

Lastpage

386

Abstract

Cooling fans for PC microprocessors often use two phase brushless motors to reduce electrical noise and to extend fan life. They are made with the winding on the inside of the motor (stator), and the magnet on the outside (rotor). This paper describes the analysis of an existing motor using a lumped parameter model. The flux paths are described and a circuit model is developed. From this model, startup and running torque are derived using the change in magnetic energy with angle. The derived torque is then compared to experimental measurements

Keywords

brushless machines; cooling; lumped parameter networks; machine theory; magnetic flux; rotors; stators; torque; ventilation; CPU cooling fan; PC microprocessors; circuit model; electrical noise; fan life extension; flux paths; lumped parameter model; rotor; running torque; startup torque; stator; two-phase brushless motor; winding; Brushless motors; Circuit noise; Cooling; Fans; Magnetic analysis; Magnetic flux; Microprocessors; Noise reduction; Phase noise; Stator windings;

fLanguage

English

Publisher

ieee

Conference_Titel

Electrical Insulation Conference and Electrical Manufacturing & Coil Winding Conference, 2001. Proceedings

Conference_Location

Cincinnati, OH

ISSN

0362-2479

Print_ISBN

0-7803-7180-1

Type

conf

DOI

10.1109/EEIC.2001.965692

Filename

965692