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THREE-PHASE MOTOR Electromagnetic fields 2011
Juan Esteban Hoyos Rosero Julian David Jimenez Cabezas Eduin Augusto Naranjo Rincon National University of Colombia Manizales caldas

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abstract— This document presents the procedure and results of a preliminary study of the project of Electromagnetic Fields about a triphasic motor. Keywords- Triphasic motor, rotor, stator, carcass, magneticnucleus, static coil, bornera.

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III. THEORETICAL BACKGROUND Nicola Tesla, a Serbian-American inventor, discovered the principle of the rotating electromagnetic field in 1882, which is the basis of the alternating current; he invented the alternating polyphasic current motors and generators system that provides the planet with energy. Without his inventions, nowadays it would not be possible todrive the growth of industries and the development of communities without electricity. The triphasic motor is composed fundamentally of a rotor and a stator. Both parts are formed by a great number of ferromagnetic sheets, with grooves in which the stator and rotor are. By feeding the triphasic coil of the stator, with a system of triphasic tensions, a rotating magnetic field is created, thatinduces an electromagnetic force in the springs of the rotor, and because all the springs form a closed circuit, then a current circulates through it, obligating the rotor to rotate in the same sense of the stator’s rotating field. Rotating motor parts: A. Stator It is the static part of the motor and is composed of: Carcass: part that serves as a support for the magnetic nucleus. It is constructed offused iron or laminated steel. Magnetic nucleus: it is a piling a ferromagnetic sheets, isolated from one another by varnishes. Stator coil: coils that have the function of producing a magnetic field. They are found in the grooves (open or semiclosed) of the nucleus. Bornera : a set of bornes located at the front part of the carcass, which serves to connect the network to the back ends of thestator coil. The bornes to which the front ends of the coils are connected to are identified currently with U1, V1, W1 and the bornes to which the back ends of the coils are connected to are U2, V2, and W2. .

I. INTRODUCTION

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wo basic types of motors are designed for functioning with alternate polyphasic current: synchronous motors and induction motors. The synchronous motor is, in essence,a triphasic alternator that functions inversely. The field magnets are mounted on a rotor and excited with a continuous current, and the frame coils are divided in three parts and fed with an alternating triphasic current. The variation of the three current waves in the frame provoke a variable magnetic reaction with the field’s magnetic poles, making the field spin at a constant velocity, whichis determined by the current’s frequency in the line of the alternating current’s potential. II. OBJETIVES  Implement electromagnetic laws in a practical application.  Present the conceptual characteristics of a triphasic motor in a general way.  Have a dominance of the concepts of electromagnetic theory involved in the project.  Meet the initial conditions arranged for the development of theproject of electromagnetic fields. III. JUSTIFICATION In the implementation of the Project will implement the electromagnetic laws, as well as fundamental characteristics of three phase motors and their interaction with electromagnetic theory. Also search to see in practice as the magnetic field affects the motor windings with the stator and the magnets of the same, and so that practice can see thebehavior of the fields studied in class.

B. Rotor Basically it is formed by an axis and a package offerromagnetic sheets with surrounding grooves for locating the rotating coils. The ends of the axis are introduced in “bujes or rodamientos” that must offer the minimum friction, so that they do not have an influence on producing an increase in the motor’s absorbed current. According to the...