Search results
Results From The WOW.Com Content Network
An induction motor or asynchronous motor is an AC electric motor in which the electric current in the rotor that produces torque is obtained by electromagnetic induction from the magnetic field of the stator winding. [1] An induction motor therefore needs no electrical connections to the rotor.
The motor always turns slightly slower than the synchronous speed. The difference between synchronous and operating speed is called "slip" and is often expressed as percent of the synchronous speed. For example, a motor operating at 1450 RPM that has a synchronous speed of 1500 RPM is running at a slip of +3.3%. In operation as a motor, the ...
A wound-rotor motor, also known as slip ring-rotor motor, is a type of induction motor where the rotor windings are connected through slip rings to external resistance. Adjusting the resistance allows control of the speed/torque characteristic of the motor.
As the slip increases, the skin effect starts to reduce the effective depth and increases the resistance, resulting in reduced efficiency but still maintaining torque. The shape and depth of the rotor bars can be used to vary the speed-torque characteristics of the induction motor.
Dahlander motor wiring for low speed (delta connection) and high speed (double star connection)The Dahlander motor is based on a 'consequent pole' connection. The primary factor in determining the speed of an induction motor is the number of poles, given by the formula
Rotor slip provides necessary induction of rotor currents for motor torque, which is in proportion to slip. When rotor speed increases, the slip decreases. Increasing the slip increases induced motor current, which in turn increases rotor current, resulting in a higher torque for increase load demands. Wound rotor; This rotor operates at ...
A linear induction motor (LIM) is an alternating current (AC), asynchronous linear motor that works by the same general principles as other induction motors but is typically designed to directly produce motion in a straight line. Characteristically, linear induction motors have a finite primary or secondary length, which generates end-effects ...
In vector control, an AC induction or synchronous motor is controlled under all operating conditions like a separately excited DC motor. [21] That is, the AC motor behaves like a DC motor in which the field flux linkage and armature flux linkage created by the respective field and armature (or torque component) currents are orthogonally aligned such that, when torque is controlled, the field ...