SKF has revealed its latest developments for improving the efficiency of electric powertrains at the 32nd International Electric Vehicle Symposium (EVS 32) on 19-22 May 2019.
Sales of electric vehicles (EVs) are poised to increase dramatically. According to a recent report from IHS Markit, these vehicles will account for more than 30% of new cars sold in key markets by 2040 – up from just 1% in 2016.
Anthony Simonin, EV and HEV Competence Centre Manager at SKF, said: “In order for these vehicles to work efficiently, the motors that drive them must run at very high speeds – up to 30,000rpm, or three times the speed of typical industrial motor – which places enormous strain on the bearings they employ.”
On SKF’s booth (E25) at EVS 32, the company showed its latest developments for overcoming this issue. SKF presented new designs for bearings and their associated polymer cages that ensure they can withstand the higher speeds, acceleration and temperatures generated by these motors, and lubricants that are able to maintain their effectiveness under these conditions.
Furthermore, SKF highlighted its insulating solutions that are immune to the current leakage, caused by the high-frequency voltage switching of the inverter that occurs when electric motors run at high speeds. This current leakage can cause pitting on the surfaces of conventional electrically conductive steel bearings, which can lead to catastrophic failure. Made of naturally insulating ceramics, SKF’s hybrid bearings negate this issue. These bearings are 40% less dense than steel equivalents (enabling them to run at cooler temperatures), have ten times the service life and require less lubrication.
Anthony Simonin explained: “SKF is also working on another solution to the problem of current leakage that promises to be more cost-effective than the use of hybrid bearings, further details of which we will share together with new developments around conductivity at EVS 32.”
SKF also exhibited low-friction tapered roller bearings (TRBs) for use in automotive powertrains that reduce power losses caused by friction by around 50% in comparison with conventional TRBs
Finally, experts from SKF were be available to discuss the company’s broad range of existing bearing solutions for hybrid and fully electric powertrains.
Anthony Simonin concludes: “EVs are the future. Though they currently account for a relatively small part of the market, making them as efficient and reliable as possible through the design of components, such as bearings, will be vital as they take a larger share.”
EVS 32 was be held in Lyon, France, on 19-22 May 2019. SKF be exhibited at booth E25.