Multi-level models

E-Drive Simulation

From concept phase to virtual testing

Modern e-drive designs have a high-power density and rotate at extremely high speeds. This leads to tough challenges in the handling of Noise Vibration and Harshness (NVH), durability, cooling and efficiency characteristics. Therefore, AVL offers simulation tools to address these challenges throughout all phases of development, from concept to virtual testing.

E-Drive in System Simulation

Our system simulation tool, AVL CRUISE™ M, helps you specify the component requirements. They act as targets for the e-motor design. As soon as the characteristics are known, it allows you to virtually perform the mechanical and electrical integration of the components into the powertrain. In addition, it can also analyze an e-motor thermal map model as part of the complete vehicle’s Heating, Ventilation and Air Conditioning (HVAC) system.

E-Motor Electromagnetic Simulation

With our e-motor tool you can perform 2D electromagnetic simulation and obtain detailed results for evaluation. Additionally, you can use all these results as boundary conditions for different engineering tasks. This includes component sizing, control strategy definition, evaluation of loss maps, investigation and optimization of e-motor cooling, structural durability and NVH.

E-Drive Dynamics and NVH Simulation

Our simulation tool, AVL EXCITE™, considers the highly non-linear interaction of flexible bodies, such as gear contacts and roller bearings. It can model the electromechanical coupling of the e-motor in both torsional and radial directions, accounting for different model fidelity levels with either fundamental, wave-based or 2D-electromagnetic-based pre-calculations. This coupling is necessary for rotor dynamics and NVH analysis.

You can also use the dynamic simulation results for durability and acoustic analysis of electrified powertrains. This includes structure and air borne noise analysis with AVL EXCITE™ Acoustics.

E-Drive Oil Splash

To avoid expensive prototyping and testing you need a deep knowledge of the e-motor’s lubrication system in advance. You can achieve this by simulating the oil flow paths in the transmission and e-motor housing under operating conditions.

This can be carried out using our PreonLab™ tool, which provides insights into oil volume flow rates at defined positions, including oil guide ribs, ducts, and channels. It also analyzes the wetting of critical components, such as bearings, overall oil distribution and oil flow velocities, as well as the dynamic oil level during operation.

PreonLab’s meshless approach makes it easy to model complex gear wheel set movements. In comparison with conventional CFD methods, this enables fast modeling with easy variant evaluations and short simulation times.

E-Drive Efficiency

Based on these dynamic results you can perform detailed investigations of mechanical friction losses of gears and roller bearings and use them for deriving friction maps. Together with drag-torque in the transmissions – which result from oil splashing (churning loss) – you can use these maps as input for CRUISE M. This enables you to investigate, for example, power flow and loss distribution during drive cycle tests.

E-Drive Thermal Simulation

For thermal analysis of e-drives you can add all relevant heat sources into the thermal models created by our 3D CFD simulation tool, AVL FIRE™ M. These heat sources can be pre-calculated as e-motor electromagnetic, as well as dynamic power losses in the gear contacts and the roller bearings. You can simulate all e-motor cooling concepts, such as free or forced air cooling, oil or water jacket cooling and oil spray cooling. Thermal simulation is possible for the structure and fluid in the same model, providing you with temperature distribution results for all components. Furthermore, you can use FIRE M to calculate the drag caused by oil splashing in e-motor and transmission housing.

Key Benefits

  • Multi-level models from concept phase to detailed component level
  • High accuracy of physically based simulation models
  • Electromagnetic expert knowledge is not required
  • The whole e-drive workflow is covered in one package and one license (except oil splash SPH)