Permanent magnet motor

A permanent magnet electric motor is a kind of brushless electric motor that uses permanent magnets instead of winding in the field.

This type of motor is used in the Chevy Bolt[1], the Chevy Volt, and the Tesla Model 3.[2] Various other Tesla models use traditional induction motors motors.[3] Front motors in all-wheel drive Model 3 Teslas are also induction motors.

Long term magnet motors are more efficient than induction motor or motors with field windings for several high-efficiency applications such as for example electric vehicles. Tesla’s Chief Engine Designer was quoted talking about these advantages, saying: “It’s popular that permanent magnet machines have the advantage of pre-excitation from the magnets, and for that reason you have some efficiency benefit for that. Induction machines have ideal flux regulation and therefore you can optimize your efficiency. Both seem sensible for variable-speed drive single-gear tranny as the drive products 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 lasting magnet machine better solved our price minimization function, and it had been optimal for the range and performance focus on. Quantitatively, the difference is what drives the future of the device, and it’s a trade-off between motor price, range and battery price that is determining which technology will be used in the future.
The magnetic field for a synchronous machine may be provided by using permanent magnets made of neodymium-boron-iron, samarium-cobalt, or ferrite on the rotor. In some motors, these magnets are installed with agricultural Chain adhesive on the surface of the rotor core in a way that the magnetic field is certainly radially directed over the air gap. In other designs, the magnets are inset into the rotor core surface or inserted in slot machine games just underneath the surface. Another kind 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 atmosphere gap.

The primary application for permanent-magnet motors is in variable-speed drives where the stator is supplied from a variable-frequency, variable-voltage, electronically controlled source. Such drives can handle precise speed and position control. Due to the lack of power losses in the rotor, as compared with induction electric motor drives, they are also highly efficient.

Permanent-magnet motors can be designed to operate at synchronous acceleration from a supply of constant 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 area to supply starting capability. Such a motor will not, however, have method of managing the stator power aspect.