INTERDICTION
By 1895, the polyphase induction motor invented by Nicola Tesla had practically developed into its present squirrel-cage shape. The slip-ring induction motor was developed shortly afterwards. Due to its simplicity and cost-effectiveness, the 3-phase squirrel-cage induction motor is now by far the most common type of engine used for industrial plant driving, especially low power ratings (up to 20 kW).The slip-ring induction motor is not as simple as the cage induction motor but its starting output and speed can be controlled by attaching external equipment (commonly resistors) through slip-rings to the rotor circuit. Three-phase induction motors may be produced to the desired output level, but normal operating speeds are connected to the power source.
The theory of motor operation
When the stator windings are connected to the three-source source a circular magnetic field is created - a field similar to the field of the poles of DC machines, but it rotates in a vacuum as if the poles of the DC were rotating. This rotating field cuts the files of the revolving organ that is restricted to itself and infer with it an electric driving force that causes the passage of currents in the revolving organ that creates a magnetic field in the rotating member that is also rotating - and an attractive force occurs between the poles of the rotating member field and the poles of the rotating member field and creates a torque that leads to The rotation of the rotor in the direction of rotation of the resulting rotating field of the stator. [5]
Rotor speed
N=NS – (S*NS)
N = Rotor Speed
S= Slip
NS = stator speed
Rotor Frequency
F1 = S * F2
F2 = Stator Frequency
Importance Three-Phase Induction Motor
General-use or three-phase induction motors are machines operating on a three-phase AC supply. These motors are inherently designed in every condition for everyday use. Which is why they are used in applications that include pumps, compressors, conveyors, pumps, material handling, and machine tools to name a few. Moreover, because of advantages such as low cost, solid design, high performance, and strong power factor, these motors are a staple of industrial applications. [2]
Why are motors with three phases the chosen choice?
Three-phase general-purpose motors have developed an eerie knack over the years to have a multitude of on-the-go utilities. No wonder their advantages range from producing little to no voltage flicker at the start of the engine to having a relatively
longer maintenance-free lifetime than single-phase engines, it!
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