- 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:

** 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