The Induction Machine Handbook

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The level of prosperity of a community is related to its capability to produce
5 E/ `5 R$ p7 ngoods and services. But producing goods and services is strongly related to the
use of energy in an intelligent way.
  ?' J6 Z0 t8 y% j0 [) A! YMotion and temperature (heat) control are paramount in energy usage.
0 |- |$ K" K7 z+ G2 I7 T% gEnergy comes into use in a few forms such as thermal, mechanical and
9 @! ^3 ?& }6 ?) o7 helectrical.
" A" c4 F" {7 D1 zElectrical energy, measured in kWh, represents more than 30% of all used
& n  J% t7 }' O& S% @. r6 Nenergy and it is on the rise. Part of electrical energy is used directly to produce
; k) F" F7 R5 Nheat or light (in electrolysis, metallurgical arch furnaces, industrial space
heating, lighting, etc.).
The larger part of electrical energy is converted into mechanical energy in
7 c) ~* Q( U1 n) u! N' W# melectric motors. Among electric motors, induction motors are most used both for
% R( E5 z% [$ T& Y4 j1 Hhome appliances and in various industries [1-11].
& H! Z, \( Z3 OThis is so because they have been traditionally fed directly from the threephase
# Q# M* Z4 Y  w5 O1 @a.c. electric power grid through electromagnetic power switches with
' ]) n4 z5 o9 W6 Y* Y6 D0 Badequate protection. It is so convenient.
' p. ]& b! J# n" c5 e" V0 p+ Y9 W1 LSmall power induction motors, in most home appliances, are fed from the
0 {: R) f- s9 K# w+ U6 m; _local single phase a.c. power grids. Induction motors are rugged and have
6 r/ }6 h/ Z9 ]& kmoderate costs, explaining their popularity.
+ [" Z/ t/ ]  v5 {$ l* c! C! X* q$ S" ]In developed countries today there are more than 3 kW of electric motors
per person, today and most of it is from induction motors.
While most induction motors are still fed from three-phase or single-phase
% D% _; H4 `  `1 T" Y7 Q1 Jpower grids, some are supplied through frequency changers (or power
1 [/ D# y) v6 I6 _' ]$ Relectronics converters) to provide variable speed.
In developed countries, 10% of all induction motor power is converted in
0 H( V" y. o, L% W5 Uvariable speed drives applications. The annual growth rate of variable speed
drives has been 9% in the last decade while the electric motor markets showed
4 i  l0 i9 {) M$ v: N( G0 B& f9 jan average annual growth rate of 4% in the same time.
! H- [" K4 E) [9 @Variable speed drives with induction motors are used in transportation,
# \! v& K! H# e  Y, k, k: Y; hpumps, compressors, ventilators, machine tools, robotics, hybrid or electric
vehicles, washing machines, etc.

! z" ^2 d, y8 Q* D6 [( N斑主,给我加点分阿,叩谢!

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好东西

afandi

好东西  已下载  多谢楼主提供

lipo

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dahu

谢谢斑竹啊