Title :
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
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;
Conference_Titel :
Electrical Insulation Conference and Electrical Manufacturing & Coil Winding Conference, 2001. Proceedings
Conference_Location :
Cincinnati, OH
Print_ISBN :
0-7803-7180-1
DOI :
10.1109/EEIC.2001.965692
