Search results
Results from the WOW.Com Content Network
The rotor is made of permanent magnet. Small synchronous motor with integral stepdown gear from a microwave oven. A synchronous electric motor is an AC electric motor in which, at steady state, [1] the rotation of the shaft is synchronized with the frequency of the supply current; the rotation period is exactly equal to an integer number of AC ...
A permanent magnet motor is a type of electric motor that uses permanent magnets for the field excitation and a wound armature. The permanent magnets can either be stationary or rotating; interior or exterior to the armature for a radial flux machine or layered with the armature for an axial flux topology.
A permanent magnet synchronous generator is a generator where the excitation field is provided by a permanent magnet instead of a coil. The term synchronous refers here to the fact that the rotor and magnetic field rotate with the same speed, because the magnetic field is generated through a shaft-mounted permanent magnet mechanism, and current is induced into the stationary armature.
The low-acceleration, high speed and high power motors are usually of the linear synchronous motor (LSM) design, with an active winding on one side of the air-gap and an array of alternate-pole magnets on the other side. These magnets can be permanent magnets or electromagnets. The motor for the Shanghai maglev train, for instance, is an LSM.
The motor from a 3.5 in floppy disk drive. The coils, arranged radially, are made from copper wire coated with blue insulation. The rotor (upper right) has been removed and turned upside-down. The gray ring inside its cup is a permanent magnet. This particular motor is an outrunner, with the stator inside the rotor. DC brushless ducted fan. The ...
Synchronous motor, it does not rely on induction and so can rotate exactly at the supply frequency or sub-multiple. The magnetic field of the rotor is either generated by direct current delivered through slip rings or by a permanent magnet.
Synchronous motors are occasionally used as traction motors; the TGV may be the best-known example of such use. Huge numbers of three phase synchronous motors are now fitted to electric cars [citation needed]. They have a neodymium or other rare-earth permanent magnet. One use for this type of motor is its use in a power factor correction scheme.
Except for permanent magnet generators, a generator produces output voltage proportional to the magnetic flux, which is the sum of flux from the magnetization of the structure and the flux proportional to the field produced by the excitation current. If there is no excitation current the flux is tiny and the armature voltage is almost nil.