Iron loss calculation example PMSM in 2d

Michael Henschel
Iron loss calculation
Iron loss, Hysteresis- and eddy current loss, Steinmetz formula
screenshot: PM_motor_basic_ironloss_constant_speed_B_and_flux.png


Hysteresis and Eddy-current losses in Synchronous machines can be estimated using the Steinmetz formula

Hysteresis loss: <m 16>P_{h}={K_{h} {B^n}_{m} f}/{rho}</m>

  • Varies linearly with frequency
  • <m>B_m</m> is the maximum flux density
  • <m>K_h</m> is usually provided by the lamination manufacturer
  • <m>n</m> usually varies from 1.5 to 2.5
    <m 16>n=B^2_{m} a+B^2_{m} b + c</m>

Eddy current loss: <m 16>P_{e}={K_{e} B^2_{m} f^2}/{rho}</m>

  • Varies with the square of frequency and flux density
  • <m>K_e</m> is usually provided by the lamination manufacturer

Estimating Bm from OPERA

  • Use OPERA-2d/RM to model the machine in transient mode (a series of static snapshots may also be enough).
  • Record a series of output times in one ‘excitation cycle’.
  • A series of commands employing TABLES is used to record the values of flux density in each element over the excitation cycle. Therefore, a flux density waveform over the excitation cycle is stored for each element.
  • Perform a harmonic analysis on the flux density waveform.
  • The iron loss per harmonic order is computed, and accumulated to the total iron loss.
  • Harmonic content and losses can be quantified and visualised

Simple PM generator

B and flux
Order 0 plot
Order 1 plot
Iron loss

Realistic PM Generator Solutions

B and flux
Order 0 plot
Order 1 plot

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models/opera2d/ironloss_pmsm/start.txt · Last modified: 2014/01/31 13:33 by mueller Valid CSS Driven by DokuWiki do yourself a favour and use a real browser - get firefox!! Recent changes RSS feed Valid XHTML 1.0