MotorCAD helps in mitigating skin and proximity effect losses in stator windings, optimizing electric motor performance.
Understanding Skin and Proximity Effect Losses
- Skin effect: AC fields induce current loops in the conductors increasing the flux linkage in the center, leading to higher reactance in this location, the result is the current flows near the surface instead of in the full cross section area, leading to higher resistance and higher losses.
- Proximity effect: similar to skin effect, but in this case the redistribution of the current is due to the flux produced by nearby conductors. Main source of AC conductor losses.
The conductors positioning has a huge impact:
In high speed electric motor applications, skin and proximity effect losses are significant factors that can affect performance and efficiency.
Full FEA Models: High Accuracy, Longer Calculation Times
MotorCAD is capable of accurately solving full FEA AC conductor losses, considering the placement of the conductor within the slot. Both single-slot and multi-slot calculations are supported. While full FEA provides highly accurate results, solving slots with numerous conductors can take several hours. MotorCAD allows users to modify and adjust conductor positions to optimize their arrangement within the slot.
MotorCAD plots Ohmic loss distribution as well:
Hybrid FEA Models: Balance Between Accuracy and Speed
To address the trade-off between accuracy and computational efficiency, MotorCAD can utilize Hybrid FEA models, which offer high accuracy while solving very quickly. However, particularly when calculating stranded winding AC losses, the hybrid model may need to be fine-tuned by comparing its results with the full FEA solution.
