40. o 1960 +--~---+---iT-.......-......-.....-+--r--+-----'I
-r;. ~ 1970 , Cio I I I o( I - :t , I f ~ 1980 _i_ Cf.:. 'L.c- ~
1990 I [, !- i I I l~ 'l-f I i I --y--- -+ -""'"0) 2000 -~ -,,-
44J6SJ1 4.iLb.l1 ~ J1iJ1 http://www.sayedsaad.com/montada
45. olin uWt.r o. JW utL~ b.l~I~ ~~ ~J ~ ~WI ~~ (jA .1&1 ~~
'":I4311~ ~ :~~/li~w.. 4'. "'" _ lIP 1) Electric system loss :
Total electric energy lossesin the electric system. It consists of
transmission, transformer, and distribution losses between the
supply and receiving points (IEEE 100 - Dec. 20(0). ~4J4-Sll ~ Jii
: ~~ ~ ~IJ~ jj IEEE 100 ~ ~~ &:d~I.J&ll ~ ~IJ~ o~ ~
~t..J+S31 ~ ~ ~Jf5J1 4lU2.U 4tsJl ~IJ~ ~ ~1.J.Jf-S.U ~':lI.J
JI~':l1 u=aw ~ ~.J.Jl1IJ ~':l~.J JAd3I ~ ~IJ~ (jA 2) Energy losses:
A general term applied to the energy that is converted to a form
that can not be effectively used ( lost) during the operation ofan
energy producing, conducting, or consuming system. : 4.it.b.n ~~J~
~~ ~ ~~ r~':l ~ ~ J~ ~I 4Jthll f"~ f"ls:. ~ ,JA r~ ~':lI.J Ji,UlJ
4lU2Jl [.:jJ1 3)Energy loss: The difference between energy input
and output as a result of transfer of energy between two points
(IEEE -1(0) : 4.iLbJI .w . 0-:U~ 0 4.ilJa.ll.t. -:t ~ ..:. .tl':' W
4.iUa 0 :: .al AlA ~ ~ fJ"...:1""""'. ~ [.;- J fJ"O O:I!'J c.;- .:r
-n- http://www.sayedsaad.com/montada
46. 4) The energy loss: is the time integration of demand
losses in successive time interval. : 4.il.b.1l .iii Ulst.l.a
4...a.lo ~l .':1t ~u ~ 0 .l11l ~ 1.1 ~. t..S.:j ~ ~..).J""'"
1,jA..J*'. ..) 6ol,JM.4 V"" ..r 5)Percent energy loss :is simply a
ratio ofpower consumed internaJly in equipment to the total energy
input. 6)Demand losses (power losses) : Demand losses are the
summation of the product of square of the load current in each
circuit element of the distribution system, at the instant of the
system maximun demand, multiplied by the resistance of the circuit
element in which it is Oowing. : i..)~ ~'J~ ~ ~ A':tI ~ A,'.e ,
,Ie' ,.1l t......:iJt ~l...La '-I' ,I,..,t.:. e ....A ~. f' '" ~ '"
I.r..) ~ .:.Y" .l)I4 4J"6I ~~ lor UJ1.4 JS3 ~ ~ ..)W 4.4JI.i.43l ~
4J~ ' f'1JalU ~ ~i ~JJa. ~ -H- tu", .e't1 UUa11 JiiJl~ ..Jt-I ~
http://www.sayedsaad.com/montada
47. 7)Technicallosses : are standard operating losses due to
physicatmechanisms inherent in the design of the distribution
circuits. This includes, for example, line heating and leakage
current due to improper grounding of equipment. Circuits that are
out of balance or have significant phase angles will also show
technical losses ~ 4.Ill ~': tt ~Itt 4.a..",w u ."..:tI 6!1~''U'
l.ot. ~ ~I.lu.tI U.Li'II_ ". f...J-ftd(S'" .JAI"..,. ~J ~ ~ ~ ~r ~
~1j.;JJJ:.:i~ .t;"p....., , ~ ~ ~ , I~ ~ ~.JjI.1I ~1JJ ~
.j14Jjl&SIJi. .;JJ.1I uti ~I o~ ~t..M3I Ji:. ~.lll ~ ~~ ~
~'J.."u.. ~.uw.... .;I.jJ:It l:!1.jJ l+1 ~ 8) Non -Technical losses
: are all the remaining types of losses, such as lossesdue to power
theft : 4lU JF ..:.a'J~ ,,4jfoSJ1 ~iJ4'l.dlP; ~IJ,JiWI &.- ~IJ~
~41lel.jol)t1 ~ ~ - y,. - ~.Jf-S.1I 'JUUt ~ JWI
http://www.sayedsaad.com/montada
48. 9)Load losses : ( power and distribution transformers)
Those losses which are incident to the carrying of~,specified load
G load losses include I2R loss in the windings due to load and eddy
currents ~ stray loss due to leakage fluxes in the 'windings, core
clamps, and other parts, and the loss due to circulating currents (
if any) in parallel wiadings , or in parallel winding stands (IEEE
100 - Dec 20(0)" :~~J~ ~"'J~ ~~ ~tJ~ If,,a1A IEEE-tOO ~ ~~ ~~t.,.JJ
~ 41 ~ ~~ ~ ~'J~ C9~ 0 i.).1M ~l1~J ~ (; ~tJJJt:.a'.Jt+mJ ~ ~'..J~
41Jii ~~~ I 2R ~ ~ ~'J~ ~ ''''J:3;; ~~J CJAJ (; ~.iW1 ~ ~ ~~ ~ ~~~,
QtJ+iJl JiiJ o (.$~~' g:.'~~' ~J ' ~ J ~~ u~ ( ~~J w' )~J.1 ~'..J~
~ ~,.) ~lJ~ ~'J II ~,~ ~WAJ' ~b.J 10)Load losses: Losses that are
caused primarily by the resistance ofthe winding conductors to the
current tha! flows through them" These losses can be reduced by
lowering the resistance of the windings and by lowering the
temperature rise ofthe transformer" :~u'J~ ~ ~.;W .;l;lU ~~ ~~
~j1.14 ().t ~~, ~~ ~ ~'J~ ~ ",,+.;J ~ OJ~ ~j ~lJ..W 4.AJt1.4 ~ ~'J~
o~ ~ ~ ~ iJ'..J'a - Yt - ~'4.Jf5J' UUa3 ~ Ji.iJ
http://www.sayedsaad.com/montada
49. 11) Load losses: lVbich arise from the resistance of
the,windings, when the transformer is in use, and from the eddy
currents which flow both in the windings and the transformer
housing due to stray flux. Sometimes referred to a copper losses,
or short circuit losses, as they are measured by shorting the
windings. ~IJJ3I ~I.;~ y..J' J~ J.aiM ~ ulJ.1.J 4..aJL i.J.ll Ul.l~
3~ ~~ J';~ ~ ~~lj J~ MJ ul..i.Wl ~ JS .,} ~ ~J uaW ~IJ ~ o.;JIJ
~IJ~ Jt ~.::;.l1I ulJ~ !dlJ~ 3~ u~ ld~1 .~~~~ 12) No- load lo-sses
: Those losses that are incident to the excitation of the
regulator. No load losses include core loss, dielectric loss,
conductor loss in the winding due to exciting current, and
conductor loss due to circuitlating current in parallel windings.
These losses change with the excitation voltage. ( IEEE-tOO) : ~
uJji..Ll : ~ ~ ~IJ~~' ~ b~1 ~ Uiji,j ~IJ~ !I~ ~.jo41I ~J ' oJ.t"'i1
.;.jd ~ ~')I ~1J.W4~.jo41I ~ , JjLII oW , ~1 .w ~ ........ ~IJ AU.I
o:tA ~. '1 .':t1 ~t.iJ." .~ l1.lJ1 l..WI ~.....,-:- ..)!lI-J r,;--
~, ..r-:-- i.$';..,..., ir: /.SJJ .;. ( IEEE - 100 ~~ ~~I~ ~ ~JJ)
f#';~' -"&1- http://www.sayedsaad.com/montada
50. 13) Core Loss: Losses that are mainly caused by the
resistance of the iron core to the magnetie flux .J)lagnetizingit
these losses can be reduced by lowering the flux density, using
higher - grade steel and careful assembly procedures. ~~ ~
($J.jJ:lJ ~ tc.,liA u.- I..al..al ~~ ~ ~IJ~ ~ l.w......u ..~.JltI
~US ..~.&':'':. ~lJu.t1 o~ ..~.&.:.,: .'.< ~ ~ fIA .;J~J
~~, ~~ "4~ ~ ~U~ ~ ~ wI." OJ,*" ~l ~ 14) No - Load losses or Iron
losses : Which result from energtsing the iron core. These are
incurred whenever the transformer is coupled to the nerwork, even
if no power is being drawn. : J:.Al ~,,,,,,u.. .ji ~ ~,,,,,,u..
J,p.aJl ~.; ~ I~ ~~ ~tJ:..t4 J:!w ~ Jl~1 V- ~1.l1l -:aIJ~ ~ J~ V-
o.;.i ~ ~ .j1." uA' ~ -n- ~'U .d 4l1.J:U1 Jii.U~ .Jt""'" ~
http://www.sayedsaad.com/montada
51. 15) Eddy current Bosses: are losses caused by the current
induced in the iron by the alternating magnetic field .. As the
magnetic flux changes with the alternaring current in the coil, a
current is induced in the iron that flows at right angles or cross
- sectionally to the magnetic flux e : ~t.JJ3l ~:.()~ utJ~
.':...,u, ... II JJ" .....t.~fl_ ~ ~ ..l.l.bJLa ~JW .1.":tl
~''''~.A ...A ~'~...J ~~ u~ ... " . ~'~~ ~ .-i JJ ":A~ J ,":tj 0.,
....t...~ ~ ~t~r.~ ~ ~~ ~ JS,J. ~ J' ~1l ~lJj o~1 ~ ~ tSln,.,
J;..bJ ~ ~~ ...t.Ui...tJl ..~ .n ~ ~ ~. I) 16) Stray Load loss (
synchronous machines) : The losses due to eddy currents in copper
and additional core losses in the iron, produced by distortion
ofthe magnetic flux by the lood current, and including that portion
the core loss associated with the resistance drop (IEEE 100) . :
J~~Jii J).JJ1 ~ .ui cJ.i ( IEEE. 100 ) ~ ~t:i3 ~~1~ ~ ~~t~n ~
..:a'J~J UMWSi ~ 4+e',J.11t ~I..)~ ~ ~..>.! (~'jl;JI ~'i5U ) te.
'" '" ,L_ tl La:la ...."'.&.oJ) ..~ .It, 0 ""'. "'... -m
,J..l~. j I.r'" tS~.J u--..) ... ~ U-:-' ~ (Jo4 ~ ",,",.j ". t.:r
4..A,Jl1.J.b~ t'j:JLtJ ~l Jii ~ ,.~ - YV - ~~Jf5J 4,iu,.n ~ .w.n
http://www.sayedsaad.com/montada
52. 17) Stray loss : Can be define as the loss due to stray
electromagnetic flux in the windings , core clamps, magnetic
shields, enclosure or tank walls (IEEE C 57,,110..1986) : 4)J.;W:J
u'J~ ~ JS ~ .).;W ~Ui..4.J~' ~ ~ ~.) .iii ~~ up ~'J~ ~ Jt
CJ'j&J1.La.....J1~J ' ~~ ~ ~J ' ~ ~l..J~Q.J ;; ~.J ~Lil.tJ
(IEEE C 57 ~ ~~ ~~,~ ~ f.ill~J) II ~ 18) Hysteresis loss (power and
distribution transformers): The energy loss in magnetic material
that results from an alternating magnetic field as the elementary
magnets within the material seek to align themselves with the
reversing magnetic field ( IEEE - 100 )" ( o..)J1ll u~~.J ~.JjUl
u'l~ ) ~, J1i ~ ~. ".. ....L.Ui..A tI ... - .".eo ~1JJ ~Ui...t.n
JW. -.i 4.iUa.n Jii ..A v-~~ U~V-" J.... !) u- vr- II
~~~~~~~~l:Y~~u.n~~~ ( IEEE - 100 ~ ~t.L.a'"..n ~ 4tUj,J) - YA-
~"4Jf-SJ 4!t.h1, ~ *! http://www.sayedsaad.com/montada
53. 19) Field 12R loss: The product of the measured resistance,
in ohms, of the field winding, corrected to a specified
temperature, and the square ofthe field current in ampers, ( IEEE
.. 100 ) " : ~12R Jii 4.JJ ~ ~, ~ ~, ,..J~'-4 ' 4..w.li..3
4...tJtL.n l.:'~ J,..,.1~.J' o ,J:HA'llj ~ e:J.)A.J ' oJJ:ll...4
oA". ( IEEE .. 100 ~ t.:a1J.,.a1~ ~ ~j.,) 20) Armature 12R loss (
Synchronous machine) The sum of the I2R losses in all armature
current paths" Note: The 12R loss in each current path shall be the
product ofthe resistance in ohms, as measured with direct current
and corrected to a specified temperature, and the square of its
current in amperes (IEEE -100 ) (4.l.';;" ~~~') ~ ~ 1 2R iii p...3'
~ ~ J.idIt ~';'" ~ 1 2R ~'J~e~ ~ ~ ~.J (-J'I4 "'-,Jli..3t ~~ J-ola.
..fA .H ;.....JS3 1 2R .1W : ~ J:HA'i4 j.,{JJ ~.)t4.J ' OJ.b.A
1I.;t..fA ~.;J JJl;. a...",a .J ,JJ.4-t (IEEE - 100 ~~ ulLa'~ ~
~jJ) - ,11 - ~~~U~~JW http://www.sayedsaad.com/montada
54. 21) Auxiliary losses: are losses caused by the use of
cooling equipment.such as fans and pumps to increase the loading
capability of substation transfomers : ~$~ ~.~ ~~.J CJI.,JAJI ~
~":l~ .tl~ ..:a1A.a f't~t ~ ~~ ~tJ~ ~ ~~ ~ ~":l~ ~ .4..J..."..,..,
o.sl.".J da~ 22) Utilization time for losses : The total duration
time needed at maximum peak power consumption to give the same
total energy losses as for the normal load duration curve. : .w.u
~'JI (jAj ~ ~ ~ ~ ~ oJ.)~ ~J ~ I"~ ~ f'IJ~ vej .,. ($JWl Ja=JlI"IJJ
~ ~ 4iUUl -:"IJ"u.. http://www.sayedsaad.com/montada
87. 10.8 b= IR Is 0.60.4 ; 0.2 "l //1 2.5 +--------+-!--f---J
/1/ j I . / ! I 2 -t-------+--t-l-.-/-/-1- 1~ / I ~r / i ".P I 1
I...... ' o IJ.. o - 'if - l~ .sJl.J:lJ ~ .w.l
http://www.sayedsaad.com/montada
88. http://www.sayedsaad.com/montada
89. ~')t '":'~ 4.itLU.J i JJin "" JW Power and Energy Losses
(Power Losses) c.)Jil ~J~ Jii Wi. ,)J1:i /f'Ji R 4..4J.L ,,:' (~4~
e;JjiJ Ji.j .1a5..Jl ) ~1.JJfS 0&4 ,,'I : ($J~ Pr ~I o,;~ S
1=-- .s S = apparent power =~W i,JJi31 P = active power = Ua.i.ll
i,;Ji1l Q = reactive power = Ua.i.lI ~ i,;JiJI Pr = active power
loss = Ua.i.lI i,;Ji1 Jii ()!.Ij, ~~ J~ ~U:a (,)4 ~J o,;l.p. ~
4Ja.i3I iJJi1 ~'JjiL J,~ OA.,H (reactance) X 4&a~ ~4J+S.11 ~~J
J1i ~ JI ~.:~I o~ : "J~ Qr ~ .;#:- o,;JiJ Jii D! ,;~/(AJI o. =3XI 2
o, =X{~)2 =X{~)2+x{~r -,,0 - http://www.sayedsaad.com/montada