Temperature effects on torque production and efficiency of PM motors using NdFeB magnets

Author

Sebastian, Tomy

Author_Institution

General Motors Saginaw Div., MI, USA

fYear

1993

fDate

2-8 Oct 1993

Firstpage

78

Abstract

The author investigates the temperature effects of PM (permanent magnet) motors using neodymium magnets on the torque production capability and on the efficiency of the motor. When PM motors are designed to operate in a wide temperature range, the reversible demagnetization of the neodymium magnets with temperature and the increase in winding resistance with temperature influence the maximum torque capability at rated speed and efficiency of the PM motor. The maximum torque at rated speed is limited due to the fixed DC link voltage of the inverter feeding the motor. It is shown that over an operating range of -40°C to 150°C the maximum torque capability and efficiency of the motor can vary over a wide range. It is also shown that for certain designs a nearly flat maximum torque versus temperature characteristics may be obtained. PM motors with trapezoidal back electromotive force waveform are considered

Keywords

invertors; machine testing; machine windings; permanent magnet motors; permanent magnets; thermal analysis; torque; -40 degC to 150 degC; NdFeB magnets; PM motors; designs; efficiency; fixed DC link voltage; inverter; machine testing; rated speed; reversible demagnetization; temperature effects; torque production; trapezoidal back electromotive force waveform; winding resistance; Brushless DC motors; DC motors; Demagnetization; Magnetic analysis; Neodymium; Permanent magnet motors; Production; Synchronous motors; Temperature distribution; Torque;

fLanguage

English

Publisher

ieee

Conference_Titel

Industry Applications Society Annual Meeting, 1993., Conference Record of the 1993 IEEE

Conference_Location

Toronto, Ont.

Print_ISBN

0-7803-1462-X

Type

conf

DOI

10.1109/IAS.1993.298907

Filename

298907