Giáo trình Bảo vệ rơ le – Dự án RE II

Giáo trình Bảo vệ rơ le – Dự án RE II
U!<jJj-+%!MPm.<l>Tl+9Al/#%/k-%Am/.<m/+%/Pk!Hk./Pl.Pm.<m/
+%/Pk!9>l+%!j#./Pl#>k
Al/AkM+j>!./Pm:+%/j%9Ak.<l%AlM+A0;/j+%#%>Tj+l0#%Tk/
/A#Aj+.<l%A%
b) Rơle điện động
Nguyên lý hoạt động
%G!MP#Jj+0T9G./Pl.<l+j%A/+!<lH`M%>%/k%:/%
%fA
[%/+jHk !A+!<lH`Md9Ak/
d
&Ak+!<lH`Mt+jHk./Pl/
t

Al/&/l#/j%>%/k%:/%%fA#A+j+Am:>j#>k
dt
w[•/
d
&Ak+j9>l+./Pl
#>kzw[‚
dt
/
t
%AM9>l+zw[
d
‚/
d
/
t
5Gs5/%A:<:GUw[/
d
/
t
.Jl#
9P+!<lH`Mt09Ak:+!<lH`Mt !AM&Ak.j#/Pj-./Pm:Pj!%A/+!<l
.>Tl+:Jj+<j/#/Pj-#%/k/
d
w/
t
w/+jUw[/
t
9!j+AkM:<:G.<l+9`l-&Tj/
+%/Pk!Hk./Pl[%/:Al+%./Pl3AM+%/Pk!&Tj/#`k5<jƒ#%/k#%/kz#%AM.<m/0
T9G5Gs9Ak:&/Pl+&Tj//Aj#/l#!=/k%+!mA9>l+./Pl#>k&Ak:<:G
[%/:<l##%A/+!<lH`M.>Tl+.<m/+%/Pk!Hk./Pl#%/k+%/Pk!:<
:G#!=/k%U
#=
+!s#%AM.<m/
Ứng dụng
T9G./Pl.<l.>Tl+5>mH!l9Ak:T9G+<5!`j##Aj+H!l0-%Am
;%Ajj#%Pm+%Pj#AlT9G5Jj#./Pl.<l.Pm#J#/l5<j:<:GU#=&Ak5Gs
#J.<l%AlM+!mAT9GAl/T9G./Pl.<l3AM+%/Pk!;%<+j:Al+%
5Jj##>k#!MU#=%m%>H!k%/Pk!##>l.<l./Pk!;%/Pm
c) Rơle từ điện
Nguyên lý làm việc
~
Giáo trình Bảo vệ rơ le – Dự án RE II
x>l9Ak:&/Pl++!mAT9G9Al/AkMH>lA#P+T5Tm9>l+./Pl#>kH#>k
#>Tk+!mAA:+%`:&/s%+>m!#Aj+H!l9P:<l#+!<lH`M;%/+jHk
./Pl+%AlM !A!MP9/j+%!=/Pm!H/Ps%>%/k%:/%%fA
>k#>TkA:+%`:&/s%+>m!&Tj/+Am:>j#>k#Aj+H!l9P
;%!+jHk#AlA:<:G !AM
>l+./Pl#>k9Akzw[•
dt

U<:G !AMUw[q#/m9Pl&Tj/Hk./Plo
Đặc điểm
T9G#>k./Pl+j.<l%AlM9Tj0+<5!`j##Aj+.<l%mq+Tsdvrdv„o
5>mH!l%/Pk!##>l.<l%jA0+<5!`j#./Pk!;%/Pm+Tsd.Pjt…
[%<9Ak:&/Pl+Tm:Al+%3AM+%/Pk!&/kTm:Al+%3AM+%/Pk!:<:G
#!=/k%U
#=
wv
d) Rơle nhiệt

T9G%/Pl#9Ak:<l#9Al/#%/Pj#=/l./PlH!k.Pm=Am&Pl.<l+T&Ak
:Al+%./Pl;%m/=/l !Aj#Am/0#%>TkH!k;Gk:&Tj/;%Tm/.<l#>k0+<#Jj+
#Tg!kTm./PlAj-3AM+%/Pk!.Pj~vv0#`k5<j~v†09Al/:Tj/
.:
.Pj
d~v./PlAj-:<l#+%/Pk!#Tj/€€vT9G%/Pl#;%<#Aj+.<l#>j+#%Tk/
#%G#/lHk./Pl&/k+j !Aj#/j%%/Pl#9Tj-%Am/+`k#%Tk//A.Pm-%Aj#
j%Tk//A9Ak:&/Pl+#>k;%Am&Ak//`M‡5ˆ.Pj&Ak/-%!j#0P;%<
H!k.Pm=Am&PlJj:Al+%.>Tl+U!<j=Am&PlJj:Al+%#%>TkH!k
;Gk:+`k!+%AmM
!MP9/jH>lA#P#Aj+H!l%/Pl#+!mAHk./Pl0AkMAM5>m
H!l-%<m=/PjT9G%/Pl#+j-%/Pj;/:9Al/;Gj-0!MP9/j9Ak:&/Pl+H>lA
#P5>l;%Aj+%A!&Pk/AsTmHAk/+!mA%A/;/:9Al/;%/=/l.<j#j%`k
#>m+T=AmT9G%/Pl#9Ak-%/Pj;/:9Al/;Gj-q=/:G#A9o+`j!#Al#>k%A/#`j:
;/:9Al/0:<l##`j:%Pl5<j/AsTm=Gjq#%>TkH!k/&A+j|‰•/0‰€•
‰
Giáo trình Bảo vệ rơ le – Dự án RE II
zGo:<l##`j:%Pl5<j/AsTm9Tjq#%>Tk9Ak.<k#%A!%AM#%Gj-+<:r
/;G0%>.<k#%A!/AsTm`j-tv9`k/&AoA/-%/Pj%Gj-9Al/&Tj/
%A!#%Ak%:<l##`j:=Jk-%>T-%Aj-+Ajj%Jl+%Ak
[%/.<j#jHHk-%/Pj;/:9Al/;Gj-!<j&Pk-%/jA;/:9Al/+j
%Pl5<j/AsTm%m%T0+j#%PmH!k#>l+#/Pj-+%Hk./Pl !A%Jl+H`M
./Pl#Tm=A !A%Pm.<l!<j+9TjMP!+`k!-%/Pj;/:9Al/-%Am/+j
+%/Pk!HAk/9Tj&Ak:mPj!+`k9>l+.`mM:Al%#%/k+%Pj#Al#`j:-%/Pj
<l0HAkM&AkJj
e) Rơle điều khiển
j+%>j+J%>:<l#T9G#!/A0%>+j;/j+%#%>Tj+%m0
#`k5<j#%A#Aj+9Tj0;%AmJJj#9Tj0%Pl5<j%Am+A
1.1.4.2. Rơle tĩnh
a) Những hạn chế của rơle điện- cơ
%.Pj;%Am%>sJ:Šv+Aj+#%/Pj#=/l=Am&PlT9G+%!mMPj!
+!s+%/m#%>l+%/Pl&Tj/+T+`j!55Aj%9Ak./Pl#>k&Ak+T;%/j0+T+`j!#%>kA
%Ak%9Ak#/Pj-./Pm:%Tl-;/:
T+`j!.&Ak55Aj%+Tr./Pl#>k+j%>s.Jl+./Pm:n
r%`l:n:Al+%./Pl#>k.:`j#;%Amtv:50+T+`j!55Aj%.k
=`mM09k30+!<lH`M%A%+!s+Tsdv:5
r[Gj:+%/j%3Aj+n&/Pl+../Pl#>k#>Tj+;/Advv0.Aj-+!mA+Ts
dvv%>Tk#%>Tk. !A=/PjHkqo~;%< !A9l+0;%/.
9`s+Am#%Ak%-%`k#`k5<j+<%/Pl-&Tj/+Aj+#%Ak%-%`k#>lH&Ak%Ak/
%>s#%Ak%-%`kAkM#%>Tk;%Aj9Tj+j#%Pm9Ak:5A/;Pj# !Am.`j#
%/Pk!
rT+`j!.&Ak55Aj%9Al/#%>Tk+%/m9Ak9Al/..T=/Pj0:<l#
Hk%Jl+:<l#Aj-%>Tk;%j#%>l+%/Pl.>Tl+%>s-%Gj-3>m9/j-%>j+
#Al-+`k+j%>+Aj+-%Gj-5<j%l+0/Am/#/j+%0-%Gj-#Ps0-%Gj-.Pj:0
g.j:!<j=Am&Pl+%:<l#.<j/#>Tl.T/Am9Ak:<l#.>TkH`M
-%`-%<j/0+!s-%Am/+`kH!k#Tj/:>Tk/-%`k#>mT9G0;Gk:#%G:<l#5T
.<k<j/H`M-%>j+#Al-+%/Pj::<l##!m#%/Pj#=/l%/-%/j+A:Ak.<l#/+`lM0
+%/j%3Aj+0#<j+.<l&Ak+Aj++%>j+J=Am&Pl#%/k;%/P:#*
b) Rơle tương tự
T9G9Al/AkM+j.Jl+#>9Ak+Aj+#%<5<j&Ak‹AT9G%>Hk0
Aj-0j+9Pl+%-%A0+<5!`j#09Ak+Aj+.Al/9>Tl9/P#!l+qAA9o/j%/Pl!
AkM.>Tl+55Aj%&Tj/:<l#%AM%/Pk!.Al/9>Tl.`k!&Ak+j/Aj#/l+%!`m
.Pm+%#/j%/Pl!.`k!AqT9G9Al/AkM<k:+Aj+9Al/T9G=AjH`s0T9G./Pl
#>mo`j!#!j+T9G9Al/AkM<k:+Aj+;%<j/5A!n
Š
Giáo trình Bảo vệ rơ le – Dự án RE II
* Khối tiếp thu
[%<j/AkM<k:%A/-%`k+%/j%9Ak=<l.9>Tk&Ak=<l55Aj%0.Al/
9>Tl.`k!A+!mA=<l-%`lAkM<k::<l##%A//Aj#/l+%!`m
p<l-%`l.9>Tkn9`jM#/j%/Pl!#>k+Aj+:AjM=/PjHk.Pm=/Pj
.<m/#%Ak%.Al/9>Tl:<l#+%/Pk!%Tk+`k!+%/m%9>!
p<l55Aj%+j#%Pm9Ak:&/Pl+#%G%A/!MP#Jj++%/j%9Akn
rx5Aj%%A/.Al/9>Tl./Pl#%G/Aj#/l#!MPl#.<j/qH!k+%+Aj+
T9G=Am&Pl;%Am+Aj+%0=Am&Pl59Pl+%0=Am&Pl !AjAj-0=Am&Pl;Gj:
Aj-0o
rx5Aj%%A/.Al/9>Tl./Pl#%G/Aj#/lj+-%AqH!k+%T9G
=Am&Pl;%Am+Aj+%0T9G./l%%>Tj+<5!`j#0o
* Khối thực hiện
U!l+./j+%+!mA;%<j/AkM#%>l+%/Pl%>s=/Pj.<m/.<l#<l#+!mA
:Al+%./PlAk/%>;%!Pj+%.Al/#/j%/Pl!.Pm.>A.Pj+!<l+Jj#:AjM+Jj#
* Khối trì hoãn
U<l#:Al+%;%Aj+.>Tl+5>mH!l##T9G#/s%9Ak:Al+%#/+%
-%`05>mH!l;%`!+%/j%9Ak:<l#;%`!;%!Pj+%.Al/#%!`l##Ajq[o
UAl+%#/j+%-%`H!k.Pm#/k%As;%<j/+%/m%./l%
Tj/T9G#/s%+%-%Gj-&/Pl++%/m%./l%+Aj+=<l-%`l#T9G.Pm
-%<j/%Tl-=Am&Pl0#%<#%>Tk+j%A/+Aj+%n
p%/m%./l%+Aj+#%<5<j.`k!&Ak.Pm-%!k%Tl-&Tj/T9G
p%/m%./l%+Aj+#%<5<j+%!`m#;%<j/55Aj%.Pm3Aj+./l%
>Ts#Aj+.<l+!mAT9G
c) Rơle kỹ thuật số
Jl+./Pm:n+Aj+#/j%/Pl!3>m9/j=P#+!mAT9G;/s#%!`l#5<jTmHAl
5<jqHAl%/l-%`v0do:Akj+j#%Pm#%>l+%/Pl%/Pk!+%>j+J#!`k#>l
/j%/Pl!.`k!&Ak.>Tl++%!MPm5A#/j%/Pl!5<j.Pm./Pk!;%/Pm#/j%/Pl!A
*) Chức năng và cấu trúc tổng quan rơle số
U<l#T9G5<j+j%>s9Al/%/Pl:&!l+%>j+J5A!n
do%>j+J.9>Tkn9Ak+%>j+J.`k!#/P&Ak !A#l%`j#0
%Jk:.09l+0#/j%A%>s#%<5<j:Al+%./Pl:AkT9G-%Am/+A%Aj+
9>Tl&Ak.`k!#/Pj/+%!9Akn
rgk=A-%A0Hk#!#/j%
rj-=A-%A0Aj-#%>j#>l†P<
Œ
Giáo trình Bảo vệ rơ le – Dự án RE II
x<j9>Tl&Ak+!l#%Pm9Al/#!kMMP!+`k!+!mAT9G%>s9>TlAkM;%/
;%<+j5>l+<j#%>Tk9Ak%/k%5/&Ak+`=Jk0Hk#!#/j%0Aj-#%>j
#>l†P<=Jk;%<%>;%/5>l+<j5Gs+j:<l#=/Pj.<l:Al%+!mA
#%Ak%-%`k#`k5<j+<%/Pl-0#%>Tk;Gk:#%G:`j#.<j/3>j;%/Pj
5/%A+Aj+#%Ak%-%`k#%>j#>l%/l+%&Ak†P<U<l#Gj#.Jl+=/Pl# !A#l
;%Aj+>sA9Ak;Gk:#%G.j#%>Tk5/%A%>s#%Ak%-%`k !Aj.<l#>lH
9Tj0;%<+%!;/k0;%/PjHkAj- !Aj.<l+<j:`j#HAl%/k%5/
g.j%>sHkAj-.&Ak+`k.>Tl+n
r/Pj%m9Al/=Jk%>s&Ak.Jl+=/Pl#q;%<=As%kA0
HAm/.<lo
rl+#%<#%`j-A#%Ak%-%`k#`k5<j+<%/Pl-<k:9l++>j0
;%/+`k;Pj#%Tl-9l+=Jk-%`k:Pk:
r%!`m%jA.Pj:>j+./PlAj-#%/j+%%Tl-0 !/./l%+Tst>j&Tj/

./l%:>j+
&Ak>j&Tj/dv
./l%:>j+

%>s&/Pl+#P#%>l+%/Pl+%!mMPj!=Jk-%`k+>j
to%>j+J9`j-:`s!0#/j%#Aj+A%5>l+<j0;%Tm/.<l+Aj+T9G
+%!mMPj!<k:+Aj+&/Pl+5A!n
p`j-:`s!Hk0Aj-0#`k5<j0.Pj:-%A.>A&Ak=<l.Pl::`s!
pl+5<j#/Pj-Pj!+`k
p/j%#Aj-%`#/j+%A+Aj+5<j9/Pl!+`k%>n
rgk0Aj-%/Pl!H!lq%Jl+5<j/A∆!0∆/o
rAj+#%Ak%-%`k#%>j#>l-%AHkAj-
rj+9Pl+%-%A
p/j%+Aj+=/Pm!#%>j+.Jl+#>5>l+<j05>Ts.Pm-%Aj#%/Pl5>l
+<j
|oAj+#%Ak%-%`k=Am&PlT9G&Ak%/+%Gj-5>l+<jn
[%/3AmMA5>l+<j#%/k:H!9+A%5Gs;%Tm/.<l+%AlM+%>j+J=Am
&PlT9G.Pm3>m9/j>j&Tj/5>l+<j`jMU<l#T9G5<j+j%/Pk!+%>j+JT9G
;%Aj+%A!H+Aj+#%>l+%/PlU<l#:H!9+%>T#/k%=Am&PlT9G
#>T>j5Gs=Jj#.`k!#/Pj-%`l9`jM%>s5<j9/Pl!.A#/Pj-#!l+H/Ps=/Pj0
.Pm#/j%./l%9>Tl+!l#%Pm+Aj+#%<5<j+!mA5>l+<j`jM&Ak#/j%A#%Tk//A
#Ps+`k+%&/Pl+•Žj•5>l+<j<k#%Tk/:<l#:H!9+!s%/+%Gj-9Al/
H/Ps=/Pj+!mA5>l+<j.Pm+j#%Pm9`jMAH!k5A!AkM
€o%>j+J•Žj•5>l+<j
~o%>j+J•jl•qPj!+jo
•
Giáo trình Bảo vệ rơ le – Dự án RE II
‰o%>j+J#>l;/Pm:#A#%/Pj#=/l0%>;/Pm:#A0.>j#0+%`l-0
;/Pm:#A./PlAj-.Pm•j•0•Žj•.!m;%<&Ak%`j#9Ak;/Pm:#A+Aj+&/
3>m9/j+j+%AlM#<j#;%<Pm+j%>s3>m9/j=Aj#/j%/Pl!%AM=Aj.<l+`k
#%/Pj#
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;%Aj+%A!#%>Tk+j%>sGj#.Jl#=/Pl#/P0;%</<j%A!Aj+
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1.2. Áp dụng những nguyên tắc điều khiển học trong bảo vệ rơ
le
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.>T+=K&)9(:8#.>?H`M./)"-+A0+"+;%*/-%B#C+,!#4P
=8-%'=K&).>E+/D/#%/)!%>%$%&]dd



Hình vẽ 1.1.
dv
Giáo trình Bảo vệ rơ le – Dự án RE II
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dd
Giáo trình Bảo vệ rơ le – Dự án RE II
1.3. Những kết quả đạt được trong việc thực hiện bảo vệ.
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