A permanent magnet motor is a type of brushless electric motor that uses long lasting magnets rather than winding in the field.
This type of motor can be used in the Chevy Bolt[1], the Chevy Volt, and the Tesla Model 3.[2] Other Tesla models use traditional induction motors motors.[3] Front motors in all-wheel drive Model 3 Teslas are also induction motors.
Long lasting magnet motors are more efficient than induction engine or motors with field windings for several high-efficiency applications such as for example electric powered vehicles. Tesla’s Chief Engine Designer was quoted discussing these advantages, saying: “It’s well known that permanent magnet machines have the benefit of pre-excitation from the magnets, and for that reason you involve some efficiency advantage for that. Induction devices have perfect flux regulation and therefore you can optimize your efficiency. Both seem sensible for variable-acceleration drive single-gear tranny as 
the drive systems of the cars. Therefore, you may already know, our Model 3 includes a permanent magnet machine now. It is because for the specification of the efficiency and efficiency, the long term magnet machine better solved our cost minimization function, and it had been optimal for the range and performance target. Quantitatively, the difference can be what drives the future of the device, and it’s a trade-off between motor cost, range and battery cost that is Transmission Chain identifying which technology will be used in the future.
The magnetic field for a synchronous machine could be provided by using long term magnets manufactured from neodymium-boron-iron, samarium-cobalt, or ferrite on the rotor. In a few motors, these magnets are mounted with adhesive on the top of rotor core such that the magnetic field is radially directed over the air gap. In other styles, the magnets are inset in to the rotor core surface or inserted in slot machine games just below the surface. Another type of permanent-magnet engine has circumferentially directed magnets placed in radial slots offering magnetic flux to iron poles, which in turn set up a radial field in the air flow gap.
The main application for permanent-magnet motors is in variable-speed drives where in fact the stator comes from a variable-frequency, variable-voltage, electronically managed source. Such drives can handle precise speed and position control. Due to the lack of power losses in the rotor, in comparison with induction engine drives, also, they are highly efficient.
Permanent-magnet motors could be made to operate at synchronous quickness from a supply of continuous voltage and frequency. The magnets are embedded in the rotor iron, and a damper winding is usually placed in slot machines in the rotor surface to provide starting capability. This kind of a motor will not, however, have means of managing the stator power aspect.