PRODUCTS & SERVICES
From insight to foresight Building the first universal test stand for e-motors provides OEMs with the knowledge to develop products without compromise OEMs having to develop solutions to brand new challenges in such short timescales can leave uncertainties around e-motor reliability, efficiency and lubricant interaction. Both OEMs and lubricant additive developers can benefit from taking a more advanced approach to testing, using specialist test rigs to generate more actionable insights. Finding a common language between hardware designers and lubricant chemists is often difficult, especially when e-motors, e-axles and the materials inside them are evolving so quickly. When fluids are evaluated by external laboratories that offer only pass/fail results, it’s even harder to build an appreciation of lubricant and hardware interactions. Lubricants that look promising on paper can still perform suboptimally for reasons that aren’t always obvious. What’s needed is a deep understanding of what is actually going on inside the e-motor. The mechanical experts embedded within Afton Chemical’s lubricant additive R&D team have been working on exactly that for some time. They are translating OEM hardware needs into bespoke test setups, creating new and more relevant tests, and designing and fabricating the mechanical rigs to carry them out. This has equipped them perfectly for their latest project: building the first universal test stand for e-motors. Tracy McCombs, technical adviser in Afton’s OEM technical services team, outlines the challenges involved. “Building a proprietary test rig that is flexible enough to test a wide range of e-motor and e-axle designs, yet still deliver reliable and repeatable results, is not straightforward,” says McCombs.
Dedicated equipment and expertise is invaluable when translating chemistry to engineering
“We’ve kept one eye on the future to ensure we can accommodate rising e-motor speeds of up to 30,000 rpm. Inverters are also acknowledged as one of the most significant heat sources in any setup, so we’re developing an option to add thermal stress cycles to our e-motor testing. The test output will better predict real world performance and generate more actionable insights for OEMs.” Having test capability in-house provides invaluable opportunities to closely observe the behavior and condition of the e-motor and the lubricant at every stage of the test process. It provides the ability for unforeseen issues to be identified
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sooner, enabling the final lubricant and hardware solutions to be optimized in harmony and the resulting benefits quantified. The advantages of direct oil cooling e-motors have already become better understood through such collaboration. Afton worked closely with a major OEM to assess the impact of using thermally efficient e-lubricant to direct cool a pre-prototype e-motor, while simultaneously assessing its compatibility with copper and plastics. A bespoke test rig, designed by Afton, confirmed the thermal modeling and demonstrated that with the right fluid, direct cooling could enhance peak
e-motor efficiency – without compromising e-motor materials. Afton has worked closely with OEMs to develop performance lubricants alongside new equipment. E-motors just are the latest embodiment of the age-old interaction between hardware and fluid. The better this interaction is understood, using relevant test rigs and a more transparent testing process, the easier it is for OEMs to mitigate risk and bring optimized designs to market quickly, reliably and efficiently. FREE READER INQUIRY SERVICE To learn more about Afton Chemical, visit: www.magupdate.co.uk/PEHV