# Iron loss calculation example PMSM in 2d

Description:
Iron loss calculation
LastUpdate:
2012-04-27
OperaVersion:
14R1
Modul:
Opera2d
Solver:
RM
Tag:
Iron loss, Hysteresis- and eddy current loss, Steinmetz formula
Screenshot:

## Description

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

B and flux
Order 0 plot
Order 1 plot
Iron loss

B and flux
Order 0 plot
Order 1 plot