20-06-2012, 05:29 PM
NEW STRUCTURE OF UNIVERSAL MOTOR USING SOFT MAGNETIC COMPOSITES
NEW STRUCTURE OF UNIVERSAL MOTOR .pptx (Size: 315.34 KB / Downloads: 30)
INTRODUCTION
Works on both ac and dc
Operates at same speed and output
Operates at speed exceeding 3500 rpm
High speed result in small size and weight
WHAT IS SMC
Powder metallurgy techniques
material is made of iron powder of high purity and compressibility
grains are bonded with a coating of an organic material, which produces high electrical resistivity.
coated powder is then pressed into solid material using a die and finally heat treated to anneal and cure the bond
permeability of this material, however, is lower than that of electrical steels.
It is expected that this material would be appropriate for construction of permanent magnet (PM) motors
It is suitable for specially structured, such as claw pole, motors with three-dimensional (3D) fluxes.
CONSTRUCTION
Main parts are
Field system
Armature
Commutator and
Brushes
Field system
It is stator and is used to create uniform magnetic field.
Commutator
Made of high conductivity hard drawn copper
Provides electrical connections between rotating armature coils and stationary external circuit
Brushes
High resistance carbon brushes used
Supplies current to armature winding from commutator
APPLICATIONS
Small power applications
Examples: Sewing machines, fans, portable hand tools, hair dryer and electric shaver
High power applications
Examples: Vacuum cleaners, food mixers and blenders, motion picture projectors and adding machines
CONCLUSION
Highly advantageous
Reduces cost
Less size and weight
Low eddy current losses
Copper requirement is reduced
Researches is reported on universal motor