CADFEM Technology Days: Electromagnetics Best Practice

MDL will be delivering two presentations as part of this event: 'Modelling of hairpin windings in Motor-CAD' & 'Electromagnetic Losses Modelling in Motor-CAD'.

  • Presented by Dr. Shaoshen Xue (Senior Research Engineer) & Dr. Mircea Popescu (Chief Technology Officer)
  • Online Virtual Event
  • 1st June 2021

Motor Design Ltd will be delivering two presentations at the CADFEM Technology Day dedicated to electromagnetics best practice.

Modelling of hairpin windings in Motor-CAD – Dr. Shaoshen Xue, Senior Research Engineer

This presentation introduces the modelling of electric motors with hairpin windings in Motor-CAD. The influence of number of layers and conductor size of hairpin windings of electric motors for electric vehicle applications is investigated. Firstly, the hairpin winding technology for electric motors is reviewed and key design rules are introduced. Based on these design rules, a traction motor with hairpin winding technology is then modelled in Motor-CAD. The influence of the hairpin winding layers on the DC and the AC copper losses is investigated, based on the results obtained considering different operating points and drive cycles. The results indicate that using a higher number of winding layers does not always lead to higher efficiency. The trade-off between DC and AC losses under different operating points and drive cycles must be considered when designing for the optimal number of winding layers. Furthermore, using a larger conductor and higher fill factor for hairpin winding not necessarily lead to higher efficiency. Finally, the optimal conductor size for electric motors with hairpin windings is identified by carrying out optimizations considering drive cycle efficiency.

Electromagnetic Losses Modelling in Motor-CAD – Dr. Mircea Popescu, Chief Technology Officer

Total losses in electrical machines can be measured accurately. The segregation in electromagnetic loss components: core, AC winding, magnets, sleeve/retainer, is difficult to achieve via experiments. Therefore, an accurate estimation of loss components via calculation is essential. Motor-CAD uses a combination of 2D FEA and analytical algorithms to estimate electromagnetic losses. In this presentation, the mechanism for all these losses is explained: causes, methods to mitigate losses and how Motor-CAD estimates such losses.