Slot design of induction motor
Based on a practical slot fill of 45 percent, the maximum number of turns would probably.3, or 69 turns per coil.
This paper constitutes a study of the impact of the rotor slot selection on the electromagnetic characteristics of the 4-pole, 3-phase, and aluminum cage induction motor, with the use of FEM.
The MLT value is converted into turns per feet to resolve the units and the value of ohms per foot for 22 AWG.162.
Moreover, the increase of the rotor slot number has as an impact the stronger magnetization of the rotor parts close to the neutral zones of the magnetic field.So, the rotor shaft diameter, the depth of the rotor bars, and the air gap length are the same in every case.Deptment of Electrical and Computer Engineering, University of Patras, 26500 Patras, Greece.In one case, a 15-slot stator is used to illustrate an odd-slot fractional-pitch lap winding.Figure.34 12-slot lamination, 2 poles, 3-phase constant-pitch lap pattern.The angular location for the phase 2 winding (CW direction) is only.5.1.3, brushless dc motors initially were designed in large numbers for spindle drives in Winchester disk drives.Consequent pole windings are very popular in single-phase ac motors of fractional-horsepower size.The stator used for the simulations is chosen from a real motor in the Laboratory, whose resistance was calculated through DC current injection spell slots 3 5 and also whose geometrical variables were known.In a three-phase motor there are three windings or phases positioned 120 electrical apart.The motors that will be simulated have 4 magnetic poles and 36 stator slots.With the aid of a FEM software, an engineer can design accurately the machine, by also providing the conducting and magnetic properties of the materials used.Figure 3: The mesh distribution in the motor with 28 rotor slots.The motor with 28 rotor slots draws the greatest starting current.Total conductors (theoretical) (SA) (turn/in2) Total conductors (theoretical).2192 x (5.12) where SA slot area The total conductors must be an even number because 2 conductors equal 1 turn.According to 15, 16, the air gap relative permeance takes the following form in order to take into account the iron core saturation, considering the fundamental harmonic: where So, the influence of the rotor and stator MMF on the magnetic flux density due to the.
Now, since this design is a four-pole bldc design, there are two full electrical cycles for one full mechanical cycle.