Induction Motors like the ones in the Tesla Model S, require no rare earth elements like EV's that use IPM or internal permanent magnet motor. Electromagnetic induction makes magnetrons in microwaves ovens possible, makes electrical energy transmission possible, make large high voltage ac transformers possible.
We can make electric transportation without rare earth metals that China controls!
In the wikipedia article on the Tesla Model S we see this:
Front and rear motor combined output up to 615 kW (825 bhp), 1,300 N⋅m (960 lb⋅ft), 3-phase AC induction motor
Ding ding ding, we have a winner, no magnets required!
These luxury performance vehicles weigh or have a mass of around 5000lbs, but wild acceleration :)
Made in America, in California too, amazingly!
As electricity moves through a metallic or super conductor, it produces magnetic fields around the outside as Vertasium shows in his video about how electricity moves through wires. Be that DC or AC, its current flow that produced a magnetic field around the conductor.
A low efficiency AC transformer can be made by wrapping coils of wire, insulated & or covered in lacquer around a collection of thin iron plates. Done inside H shaped iron laminated sheets, a magnetic transformer formed. This robust type of heavy wall wart adapter, or magnetic ballast, or electromagnetic transformer are resistant to operating in very cold & hot environments & can last decades, though their electrical efficiency is less than electronic switching type transformers that are more common now, these magnetic ballasts & transformers are much longer lasting with 10-20x the operating life of the fragile easily broken low lifetime electronic equivalents that have better energy efficiency.
Tesla's AC induction motor & VDF controller or poly-frequency produces a motor generator set that can recuperate up to 60kw of regeneration energy to charge the DC energy storage battery array or traction battery.
China raised rare earth metal prices up to 500% within a 3-month period in 2011 & prices for neodymium & dysprosium have remained high, causing magnet makers outside of china to experience cost related shutdowns & supply chain issues related to only have 1 supplier of the elements used for making the magnets.
IPM or internal permanent magnetic motors offer very high electrical efficiency of up to 98% at a cost structure known as premium efficiency, & can utilize variable frequency AC or DC electrical energy & also offer nearly instant torque response & a very broad power output band across different rotation speeds, nearly ideal for things like my 2017 Segway Mini Pro, made by Ninebot in China- the OG magnesium alloy body with larger battery model for $1000, not that plastic iron unit for $499 that superseded it. Most electric bicycles use IPM motors as they are lighter than induction motors, smaller & offer amazing power, torque, useful in electric scooters, motorcycles & electric cars, SUV's, buses, trucks, & other applications. In rail cars large induction motors that are not mass constrained offer a unique sequential variable speed drive solution, also used in isopods propeller drive units on large yachts & ships. In solar electric boats & battery electric boats with Minnkota electric motors, similar IPM electric motors are used. Nearly all RC drones use fixed coils with magnets mounted to the prop drive to make powerful low mass high efficiency electric motors in DJI & other drones from Parrot & others.
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