The Induction Machine Handbook

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The level of prosperity of a community is related to its capability to produce
: X7 j) u' w* {goods and services. But producing goods and services is strongly related to the
' E, X% Z4 r' ~' i7 _6 e# _4 [+ s+ Yuse of energy in an intelligent way.
Motion and temperature (heat) control are paramount in energy usage.
Energy comes into use in a few forms such as thermal, mechanical and
electrical.
Electrical energy, measured in kWh, represents more than 30% of all used
% I  }  ?8 J5 r$ |# Y; Renergy and it is on the rise. Part of electrical energy is used directly to produce
; c1 L9 h4 y7 s- j# C) vheat or light (in electrolysis, metallurgical arch furnaces, industrial space
1 V# _( z3 D5 j4 m  a, l- `, bheating, lighting, etc.).
, M& |* V2 l7 p2 X! ]) o6 WThe larger part of electrical energy is converted into mechanical energy in
electric motors. Among electric motors, induction motors are most used both for
home appliances and in various industries [1-11].
8 B8 ~$ q/ R6 X- Y" D" [6 ~This is so because they have been traditionally fed directly from the threephase
' q+ R) j3 ?0 x6 W0 ~& g) M0 k4 Ua.c. electric power grid through electromagnetic power switches with
adequate protection. It is so convenient.
/ Z9 u: t+ H/ S: X- z* n. WSmall power induction motors, in most home appliances, are fed from the
local single phase a.c. power grids. Induction motors are rugged and have
5 O/ O* w4 W7 N, M6 f8 Amoderate costs, explaining their popularity.
# m! g+ K. w7 HIn developed countries today there are more than 3 kW of electric motors
9 ~& T/ S9 R6 G, N- uper person, today and most of it is from induction motors.
# z% X4 D# V" V6 @While most induction motors are still fed from three-phase or single-phase
; I% C) M( Q& C( rpower grids, some are supplied through frequency changers (or power
electronics converters) to provide variable speed.
* g4 e6 F( ]. z6 G7 DIn developed countries, 10% of all induction motor power is converted in
variable speed drives applications. The annual growth rate of variable speed
1 n3 G  Y, `8 A/ C0 s3 N8 cdrives has been 9% in the last decade while the electric motor markets showed
an average annual growth rate of 4% in the same time.
0 N$ v. ?4 d6 u" B8 Y3 c9 u4 ]- wVariable speed drives with induction motors are used in transportation,
pumps, compressors, ventilators, machine tools, robotics, hybrid or electric
( B, t' \8 D  i0 |, b3 R. x/ z7 `vehicles, washing machines, etc.
6 Q$ Q( ?, o6 {7 c/ }# o
) }( A; z4 ^8 L/ Q1 A, i. `斑主,给我加点分阿,叩谢!

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afandi

好东西  已下载  多谢楼主提供

lipo

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dahu

谢谢斑竹啊