The influence of rotating field direction on core losses in electrical machine laminations

The measurements of rotational core loss in machine laminations show significant differences in losses when the rotating field reverses its direction from clockwise (CW) to counterclockwise (CCW) direction of excitation. A novel design of a magnetizing test fixture based on an electromagnetic Halbach array is used to perform measurements on a non oriented silicon steel sample of M36G29 at three different frequencies of interest to the industry 60 Hz, 400 Hz, and 1 kHz. The experimental results are fed to three types of electrical machine models, 2-pole induction machine (IM), 6-4 switched reluctance motor (SRM), and 2-pole brushless DC machine (BLDC) to investigate the effect of reversal of the rotating field direction on the delivered core loss in the stator. Results reveal that the IM experiences the highest effect of field reversing followed by the BLDCM, and then the SRM which is the least affected.

[1]  Jianguo Zhu,et al.  Improved measurement with 2-D rotating fluxes considering the effect of internal field , 2005 .

[2]  Pragasen Pillay,et al.  Design of a Novel Test Fixture to Measure Rotational Core Losses in Machine Laminations , 2012 .

[3]  K. A. Hempel,et al.  Power loss in electrical steel under elliptically rotating flux conditions , 1996 .

[4]  Takashi Todaka,et al.  Counterclockwise/clockwise (CCW/CW) rotational losses under high magnetic field , 2009 .

[5]  Jianguo Zhu,et al.  Measurement and Modeling of Rotational Core Losses of Soft Magnetic Materials Used in Electrical Machines: A Review , 2008, IEEE Transactions on Magnetics.

[6]  Afef Kedous-Lebouc,et al.  Macroscopic anisotropy characterization of SiFe using a rotational single sheet tester , 1995 .

[7]  Nick Stranges.  An investigation of iron losses due to rotating flux in three phase induction motor cores , 2000 .

[8]  S. Yanase,et al.  2-D magnetic rotational loss of electrical steel at high magnetic flux density , 2005, IEEE Transactions on Magnetics.

[9]  Anthony John Moses,et al.  Importance of rotational losses in rotating machines and transformers , 1992 .

[10]  K. Atallah,et al.  Calculation of the rotational power loss in electrical steel laminations from measured H and B , 1993 .

[11]  J. Sievert,et al.  Two-dimensional magnetic measurements - history and achievements of the workshop , 2011 .

[12]  Turgut Meydan,et al.  Errors in the power loss measured in clockwise and anticlockwise rotational magnetisation. Part 1: Mathematical study , 2006 .

[13]  Turgut Meydan,et al.  Errors in the power loss measured in clockwise and anticlockwise rotational magnetisation. Part 2: Physical phenomena , 2006 .