Tesla Model 3 sees automaker’s first use of permanent magnet electric motors
March 12, 2018
Tesla’s Model 3 electric vehicle will be the company’s first car to incorporate a permanent magnet electric motor, reports Reuters. The automaker has previously relied on AC induction motors, such as those used in its Model S and Model X.
Neodymium permanent magnets are widely used in electric and hybrid automotives and are said to be lighter, stronger and more efficient than induction motors in general. The research group IMARC estimates that the market for neodymium-iron-boron magnet used in Tesla’s motors is now worth more than $11.3 billion, with demand rising at a compound annual growth rate of 8.5% between 2010 and 2017.
Speaking to Charged Electric Vehicles Magazine during a panel at the Coil Winding, Insulation & Electrical Manufacturing Exhibition (CWIEME) in Chicago, USA, in late 2017, Konstantinos Laskaris, Tesla’s Chief Motor Designer, stated, “It’s well known that permanent magnet machines have the benefit of pre-excitation from the magnets, and therefore you have some efficiency benefit for that. Induction machines have perfect flux regulation and therefore you can optimise your efficiency. Both make sense for variable-speed drive single-gear transmission as the drive units of the cars.”
“So, as you know, our Model 3 has a permanent magnet machine now. This is because for the specification of the performance and efficiency, the permanent magnet machine better solved our cost minimisation function, and it was optimal for the range and performance target. Quantitatively, the difference is what drives the future of the machine, and it’s a trade-off between motor cost, range and battery cost that is determining which technology will be used in the future.”
According to Tesla, the Model 3 is “a smaller, simpler and more affordable electric car” than the company’s previous models, and has been designed and built as the world’s first “mass-market electric vehicle.” It is expected to begin shipping in Europe in late 2018, and is currently on display at the Geneva Auto Show, Geneva, Switzerland, March 8-18.