To outline the state-of-the-art from the engineering point of view about Electric motor cooling in automotive applications, involving academic world and industries, it was organized a highlighting workshop that has called, to share their vision, players in automotive induced activities, from OEM, to Tier One and Tier Two suppliers. Technology is evolving to allow higher and higher efficiencies and more performing motors.
How much is it important, what is the state of the art and what are next technological moves concerning the electric motor cooling in automotive applications? Outstanding representatives of the academic and industrial world have provided their expertise and vision on this issue.
At the helm of the event, organized by Electric Motor Engineering and Tecniche Nuove and broadcast last January 31st, we have found Professor Marco Villani, professor of Electrical Machines Design and Electric Systems for Mobility at the University of L’Aquila.
The session was opened by Alessandro Ventura, Corporate Technical Director Meccanotecnica Umbra, who has cast the spotlights on Mechanical seals for electric motors cooling systems. The range of products he evaluates includes Mechanical Seals for different appliances: for automotive, for household, for aviation sector, but also for medium-duty and Hi-duty application and for hydropower applications.
Reference markets are manifold: automotive, aviation, agriculture, food&beverage, mining, energy, refrigeration, civil sector, appliances, Pulp&Paper, chem/pharma and industrial general purpose.
The stator housings and Rotor shafts for Electric motors with integrated cooling circuits were instead the theme of the speech by Philipp Bucher, Head of Sales LCD LaserCut AG. Under the magnification lens, the added values of 3D additive manufacturing in terms of improved motor cooling: integrated housing cooling, integrated shaft cooling, integrated end shields cooling, integrated power electronics cooling, integrated peripheral features, integration of weight reducing holes and minimal material need. Among the important topics that they have considered in 3D additive manufacturing there are housing and shaft designs that need to be developed from the very begin, based on the specific 3D manufacturing requirements and chances.
Giada Venturini, E-Machine Engineer Motor Design Ltd, and Husain Adam, Thermal Specialist Engineer Motor Design Ltd, spoke instead of Advanced Software for Thermal Analysis of Electric Motors. High power density, high efficiency, low cost are the advantages that can be given by advanced cooling systems. Several solutions and configurations for eMobility are discussed more in details.
«Thermal response analysis is essential for meeting the performance: machine operating temperature limits the electric loading, increasing in operating temperature cuts insulation life, magnet performance is very sensitive to temperature and copper loss is temperature dependent.
The message sounds clear: effective thermal management is critical to ensure high power dense machine lifetime and reliability. The two young engineers stressed Ansys Motor-CAD capabilities concerning both thermal and Cooling types. Wide room was also dedicated to Direct Stator Cooling & Flooded Stator Cooling and to Oil Spray Cooling, Oil jets and Oil Dripping Cooling.
The workshop was ended by the speech EV/HEV motors and advantages in terms of thermal dissipation through potting, delivered by Alberto Menozzi, Plant Manager – Technical Director, Demak Polymers of Demak Group, which can boast mechanical and chemical know-how: the company’s great value precisely derives from the combination of these two competences.
The core of his speech is the resin encapsulation of electric motors for EV/HEV applications.
Thanks to the experience gained during these last years, many advantages of a full resin potting compared to other technologies, such as impregnation and trickling. The resin is a perfect electrical insulator, and it delivers properties that are absolutely incomparable to other insulating methods, including: enhanced water and dust resistance, chemical resistance, less vibration, less noise and most of all, perfect heat dissipation and improved thermal shock resistance.