Applications of single and three phase induction motor single kontakt Chemnitz
An induction motor is therefore an asynchronous machine The relative motion between the rotating field and the rotating rotor is called the slip and is given by: S = is the rotor speed.
Since the rotor current is proportional to the relative motion between the rotating field and the rotor speed, the rotor current and hence the torque are both directly proportional to the slip.
The actual speed of the motor depends on the load it must drive.
Ignoring the effect of the back EMF set up by the induced currents in the rotor windings, the flux density B will be proportional to the applied voltage.
History The stator carries the motor primary windings and is connected to the power source.
Increased rotor resistance also has the added benefit of reducing the input surge current and increasing starting torque on switch on, but all of these benefits are at the expense of more complex rotor designs and unreliable slip rings to give access to the rotor windings.
Synchronous speed in RPM is given by: Nis the powerline frequency in Hz and p is the number of poles per phase.
There are normally no external connections to the rotor which carries the secondary windings. When a current flows in the stator windings a current is induced in the shorted secondary windings by transformer action.