Giáo trình Bảo vệ rơ le – Dự án RE II

1.1. Những vấn đề cần đề cập trong việc thực hiện bảo vệ hệ
thống cung cấp điện.
1.1.1. Những vấn đề chung về bảo vệ rơle
 !"#$%&'%(%%)#%*+!+,-./)0+1#%23!,#%/)
#$%#456+*&(+%7.89(:&/)+;%<=$%#%>?+@A+"+-%B#C
-%B9D+"+#>?%E-0+"+56+*#%>?;F#%G%/)
#>EHI./)#J;%"+A&(./)"-/K:;%"#%,-
"+#%/7#=L+1HI#J+A+%4M !A+1#%2=L.*#1 !":N+
+%-%F-&(=L%>%O;%/./)"-=L/K:#%,-0+"+%8#/P!#%Q;%<
#%29(:&/)+=$%#%>?&(#R%S.L%+@A+"+:"M-%"#9(:&/)+5
5&(+@A#(%)#%*=L/K:
"++%7.89(:&/)+;%<=$%#%>?9(:+%./)"-0HI
./)&(#B5*9)+%;%O//D/%4+%-%F-&(7!.2;FH(/#$%#4
(M+1#%23!,#%/)56+*
%>&'M56+*9(:*/9456%4#.8=$%#%>?+@A%)
#%*1/+%!&(+"+%8#/P!#%Q1//P0+I+"++%7.89(:&/)+
;%<=$%#%>?+1#%2#4!M+T3!,#%/)56+*
U!*H!M#$%4#.8=$%#%>?+@A%)#%*&(+@A+"+%8
#/P!#%Q;%/3!,#%/)56+*0+B-%"#%/)+(%A%+(#*#+%V56+*
&(+"+%9M+%WA;%O/-%B;%<=L%>%O0H.1-%B+I94/&X
H!M#$%4#.8=$%#%>?0.Y#%?/9(:/K:.>E+56%>%4/+@A
-%B=L56+*
%/7#=L=K&)T9G9(94/#%/7#=L#6.8=K&)+1+%N+J
#%6+%/)#*#MP!+B!P!#P
"+%)#%*./)%/).4/;%<#%29(:&/)+=$%#%>?7!
#%/7!#%/7#=L=K&)T9GK&)T9G#%GHZ/9/P#Q+#$%#4&(+%7
.89(:&/)++@A#,#+K+"+-%B#C+@A%)#%*./)[%/3!,#%/)56+*0
=K&)T9G+\#-%B#C%>%O094/1A;%O/:4./)%?:"M+\#
./)

pT9GHk./Pl
pT9G./PlAj-
pT9G+<5!`j#
pT9G#<m#Tm0
Ho%`9Al/#%G+Aj+%:Jj++T+`j!
pT9G5T+`j-n9Al/AkM.>Tl+:Jj+#>l+#/Pj-&Ak:Al+%./Pl+`k=Am
&Pl
pT9G#%>j+`j-n9Al/AkM:Jj+&Ak:Al+%#%< !A=/PjAj-.
9>Tk%AM=/PjHk./Pl
Go%`#%G/Aj#/l&Ak+%/Pk!+Aj+.Al/9>Tl./&AkT9G
pT9G+>l+.Al/
pT9G+>l+#/Pm!
t
Giáo trình Bảo vệ rơ le – Dự án RE II
pT9G+>l+.Al/r+>l+#/Pm!
pT9G59Pl+%
pT9G./l%%>Tj

1.1.3. Đặc tính vào -ra của rơle

u!A%Pl/>sA.Al/9>Tl&Ak&AkA+!mAT9G%>%/k%:/%%fA
[%/3=/Pj#%/P#>kv.Pj3t#%/kMwMd.Pj;%/3w3t#%/kM#J#>k
MwMd.PjMwMtq%AmM=`l+oPj!3#J#/Pj-#%/kM;%<.<m/MwMt[%/
3/Am:#>k3t&Pk9Al/3d#%/kMwMt.Pj3w3d#%/kM/Am:#>kMt&PkMwMd
1.1.4. Các loại rơle thường gặp trong hệ thống bảo vệ Rơle
1.1.4.1. Rơle điện cơ
a) Rơle điện từ
Nguyên lý làm việc
x>l9Ak:&/Pl++!mA9Al/T9GAkMH>lA#P!MP9/j./Pl#>kyGj#:<l#
T9G%>%/k%:/%%fA[%/+%Hk./Pl/./&Ak+!<lH`M+!mAA:

+>m!
T9G-%`+>l+:Al+%#>kA:+%`:&/s%+>m!+j+`j!#!j+5A+%
:<l#-%/jA;%G%Tm;%<;%/j9Tj+k:<l#-%/jA%m.Pm;%/+%Hk&Ak
+!<lH`MA:+%`:#%/k#<m9>l+%!j#./Pl#>k+!mA+!<lH`M&AkA:+%`:
&/s%+>m!-%`+>l+%A/=P;%<=Jk%A!0Jj-=/l%!j#&Pk:<l#=P09>l+
%!j#A:+%`:&/s%+>m!9Ak:%/Pl:&!l/>sJj-;%/+Jj#./Pl+!<lH`M
€
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

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;%<

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

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/

.K:569(:&/)+#*#%,#+@A=8-%'=K&)
S%E-+"+=8-%'=K&)+@A:8##A#%/7#=L+1#%2Y:,#
%/b!;%*/-%B#C+,!#4P%'#&'M0/K#%/7#’#A#%/7#=L
.>T+=K&)9(:8#.>?H`M./)"-+A0+"+;%*/-%B#C+,!#4P
=8-%'=K&).>E+/D/#%/)!%>%$%&]dd
Hình vẽ 1.1.
dv
Giáo trình Bảo vệ rơ le – Dự án RE II
[%*/-%B#C.7.>E+f/9(%c-%B#C%4M+K:%W
%'.>E+#%<#/&(+%7.89(:&/)++@A.>?H`M.>E+=K&)#h
:"M=/7HI&(#h:"M=/7./)"-[%*/+1#%2Y:n=8
9f+#%(%-%B#%N#6%L+%%AM.Y+6+0=89f+51%(/='++A0
%_+%c=8-%';%"+._+#>+%+%7.8&'%(%.>?H`M
%c/"#L+@A.4/9>E:(;%*/%'.>E+0.>E+55"%
&D/%c/"#L.•./b!+%“%+@A+"+-%B#C#%(%-%B+@A1
%c/"#L.•H/b!+%“%(M.>E+#%/7#9'-;%/#%/7#;7=K&)
%c#%<#/5A!;%/55"%.•+1;7# !K.>E+#!Mb.7
;%*/3C9‘&( !M7#.L%g
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+%>T#$%.•.>A&(#>D+.`M;%/#%/7#9'-5T.Y*/&(;%/./b!
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:8##R%/)!+%;%*/+%,-%(%q.</;%/+If/9(;%*/Ao.2;%*/
(M#/7%(%#%6+%/)+\#:"M+\#./)&(-%"#:8##R%/)!
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(+e;%<=A/?#%6+%/).>E+;%/
;.
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-#:A3
qdr€o—
.`M
.: 
&(
-#:A3
9(HI./).L%:N+&(HI./)-%Q#K/9D%,#
##A#%/7#=L.>E+=K&)$=K&)5];%<#"+.8#+%7
.89(:&/)+=$%#%>?0+%7.8.L%:N+%AM+%7.8-%Q+#K/:A30P
+B-%K/+%,-%'n

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-#:A3
qdr~o
u!A%)qdrto&(qdr~o+%#A#%,Mn#A5]%'.>E+:8#.8%4M

#%$#%$-%K//K:HI./);%i.8+@A=K&)
;. 
0./b!(M#>T
N&D/&/)+#J%)5*%4M
q&$[
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ngm :/
o
[R+%#%>D+=A=$+@AT9G./)#C#%>?+%“=F=’d‹|%_+
d‹€5&D/;R+%#%>D+=A=$+@AT9G./)+Th.`M+%#%,M&/)+5C
d‰
Giáo trình Bảo vệ rơ le – Dự án RE II
HQT9G./)#C+%-%F-/K::8#5*9>E.";2+"+=K\+"+
#%/7#=L=K&)g&'M0;R+%#%>D++@A/AH/b!;%/2#!/A+e
.>E+/K:
Độc lập đối với điều kiện vận hành:K&)-%K/.>E+#%/7#;75A
+%.K:=K#"+.8.W;%/3!,#%/)56+*i#%/7#=LH>E+=K&)
2.K:=K./b!;/)(M#%$%c/"#L;%i/.8-%K/.>E+
#R%#"H6A#P+"++%7.89(:&/)+max &(min +@A#%/7#=L.>E+=K
&)%>&'M#A-%K/;/2:#A56#"+.8.W+@A=K&)i+K%A/+%7.8
#P#N+9(.K:=K.>E+MP!+B!.8+9'-.*/&D/./b!;/)&'%(%
T9G./)#C+1:8#>!./2:9(+1HK//"#L./b!+%“%80.Y#%?/
,#.T/K.*/&D/=8-%'#%6+%/)./b!+%“%
1.3.2. Các yêu cầu khác đặt ra đối với bộ phận bảo vệ.
a) hiệu quả kinh tế:[%/96A+%f+"+-%>T"#*#%,##
#%/7#;7=K&)=’T9G0+%W#A;%<+B+%W‘.7M7!#*;/%#7&b
.B!#>=A.B!&$’55"%&D//".B!#>+@A#A#%/7#=L.>E+=K

#%7+"+#S%E-=L56+*
/)+xCHQ+"+:4+%/#P+"+=K:H!9#4P#R%HK:
=K+A%T&$94/A.>E+%c5A/-%4:+1#%23KMAH+"-*/
1:94/#h&/)+-%`#R+%+"++%“#/P!;–#%!'#&(+"+MP!+B!;%"+
._#A.*/&D/569(:&/)+&(#%6+%/)=K&)+@AT9G0#A#%,M’n=K
&)./)#C#%6+%/)=’+%,#="HXq+I+1#P=K&)#”%0#>T
N&D/+%!M2:4+%#”%&$;%<+1%c#/7-./2:+T;%R&(%c
-%B#C+%!M2.8o#%K:•%c+%“#/P!;–#%!'##./b!;/)
#*#%,#&(#%/b!#>?%E-+1%/b!>!H/2:%T5&D/T9G./)
+T$#%71/K/#%R+%.>E+#4/5A(MAM>?/#A#%R+%H^=K&)
=’T9G./)#C%T&(HBHB1#%AM#%7+%T9G./)+T
1.4. Sơ đồ cấu trúc của bảo vệ
#>?%E-=K&).T/K0%’:;/2:#A56#%AM.S/+@A
:8#.4/9>E(.15&D/:8#/"#L:*+q/"#L !M+%/7!o%>9(
=K&)HI./)0=K&)./)"-0.>E+#%6+%/ž=’T9G./)+T#%$
>?/#AH•H(H^5T.Y./)!MP#\+.2=/2#%L5T.Yq+If/9(
5T.Y+%R%o/b!(M#%6+%/).>E+&$5*9>E:4+%&(%c-%B
#C+,!#4P+IR#P;%<+B#%/7#5T.Y#/2;%A/
#>?%E-=K&)-%N+#4-0MP!+B!-%K/55"%%A/.4/
9>E#%G=/P.8%AM569)+%-%Aq%>=K&)+1%>D059)+%0
;%K+"+%o&$15]#"+.8;%/;7# !K%'.>E+#h5655"%
&>E# !":8#/"#L/D/%4(.10#N+9(5T.Y+1#%2=/2!#%L:8#
:N+.8-%N+#4-+A%T .</;%/:V/:8##%A/.4/9>E.>E+5
5"%94/.*/+%/7!&D/:8##S%E-+"+.4/9>E;%"+h.1;%/%c
=K&)-%N+#4-#%6+%/).*/&D/T9G./)+T0>?/#A5]H^5T.Y
#/2;%A/.2=/2!#%LxT.Y#/2;%A/(M+%-%F-#%GHZ/:4+%H•
H(%T
&(5T.Y9\-"-—5T.Y=*#R0%c:*/ !A%)/cA+"+-%B
#C+1#%2;%<.>E+-%K"%:8#+"+%.BM.@:(+%“#%2%/)%)
#%*=K&)+@A:8#5*%,#.L%#A#%/7#=L.>E+=K&)=’+"+%

5A!n¡000[¢£¡0[¢£0œ—+"+
-%B#C(M0%c=/7#%/PiZ&(&(ZA+%“+1#%2+1%A//"
#L+@A.4/5*9G0#%<#%>?;‘%/)!9(¤v‚&(¤d‚
P+4%%c-%B#C9/+%>.•P!#P0#5T.Y=K&)
T9G+I5CHQ8•/%c=89/++1#P9(=8-%`=/)#—%c
-%B#C9/+(M0=/75*&(+156=/7.S/9/P#Q+&(+1#%2+1:8#5*
9>E&<#'+"+/"#Lq=AY:#/D/%4:8#HK/%,#.L%o#
;%/=/7+*ZA+%“+1#%2+1%A//"#L¤v‚%_+¤d‚*/&D/-%B#C
(M0:<#K#"%f++@A569(:&/)+.>E+#%6+%/)%?9/+%(:
$+"+.4/9>EZ&(+1:8#/"#L9/P#Q+0+I.4/9>E.B!
A+%“+1%A//"#L0=8-%`=/)##%6+#79(%c-%B#C9A/
2+1#%2HI#$:%c/".4#56=/7.S/+@A=/P.8
%AM569)+%-%Aq&$56/".4=/2!#%L3!,#%/)56+*oP#%6++%,#
T9G#%6+%/)+%N+J=8-%`=/)#g.1##%6+#7%c-%B
#C%F-9A/;%<#%2&\:_##5T.Y=K&)./)#C
x5"%&D/:8#5*-%B#C#>T#60-%B#C9/++1>!./2:9(
.K:=K569(:&/)+#*#+@A#A†/#0&$%c#A†/#(M9(:&/)+i
+%7.8+%!M2:4+%#5T.Y-%B#C9/+>T#6K%%>i+@A
d•
Giáo trình Bảo vệ rơ le – Dự án RE II
56#%AM.S/%/)#.8.*/&D/569(:&/)++@A#A†/#i+%7.8+%!M2
:4+%#%$R#%TK%%>i+@A56#%AM.S/%/)#.f#+%7.8-%B#C
#>T#6
1.4.2. Những phần tử tương tự trong sơ đồ bảo vệ điện tử.
¥#%T5&D/%c-%B#C9/+5*%c-%B#C#>T
#6#!M7#R%&(;%<#!M7#R%0+%W#A#%>?_-#=K&)./)
#C%e=8-%'5A!n=8;%!7+%.4/0;%!7+%.4/#%!'##"9(:&/)+%>
:8#=8+80=8#R+%-%`&&œ-%B#C%`=8/0-%B#C9)+%-%Aœ
:8#5*#>?%E-0#+^:8#5T.Y=K&)#A&hA_-
-%B#C9/+&hA_--%B#C#>T#6%'#&'Mn.4/9>E;7# !K#h

Giáo trình Bảo vệ rơ le – Dự án RE II
9D%T#%?//A#"+.8+@A=K&)+%R%.2+%=K&)+%R%#%6+
%/)%/):&Q+@A:$%9(94/-%›#C=L56+*A;%O/:4+%#>D+#/P
q;%/=K&)+%R%9(:&/)+.Wo
 !"#$%%/P+N!=K&).*/&D/+"+-%B#C;%"+%A!
+@A%)#%*./)0=K&)H6#c+%=K&)+%R%+1#%2.>E+.K:=K
#%G=A+"+%5A!n
Ao K&)+%-%B#C=P+4%q=K&)(M.>E+f/9(H6#c
;%K+(+%o
=o K&)-%Q._##P+^-%B#Cq=K&)(M+1#P9(H6#c
#4/+%Vo
+o U8#T9G-%Q.>A&(#5T.Y=K&)+%-%B#C=P
+4%0T9G(M5]./b!;%/2:i:"M+\#+@A-%B#C:(#A !A#`:
1:8#5*#>?%E-=K&)+%R%;%<.K:=K=K&)#(=8
+%/b!H(/+@A:4+%+B#%/7#=K&):(5]+1:8#5*.4.>E+f/9(
&^+%7#+@A=K&)+%R%0&$7!56+*3!,#%/)#4/&^+%7#(M#%$
=K&)+%R%5];%<\:=\#.>E+&(H.115];%<#"+.82
+1#%2.K:=K=K&).*/&D/+"+56+*3!,#%/)#4/&^+%7#(M
>?/#A._#:8#94/=K&)+1#P9(=K&)-%Q
—:8#5*#>?%E-+Q#%20=K&)H6#c+1#%2#%K:•&A/#I
+@A=K&)-%Q+@A-%B#C#>TN
1.6. Những loại bảo vệ chính bằng rơle.
1.6.1 Bảo vệ dòng điện: K&)HI./)#"+.8##>?
%E-HI./)+@A:4+%=K&).>E+#J9PH !"#K/%AM\:4+%
%c=K&)(M#%6+%/)=’T9G+>?.8q+If/9(T9GHI
./)oT9G5]#"+.8;%/HI./)#:4+%.>E+=K&)&>E# !"
:8#/"#L%,#.L%.•.>E+#%/7#9'-gI./)(Mf/9(HI./)
;%i/.8qHI./)#"+.8o+@A=K&)&(;‘%/)!9(
;.&
/"#LHI./);%i/.8+@A=K&)9(/"#LHI./)+@A

#LHI./)+6+.4/+@A-%Q#K/0#N+9(n

;.&
{
.:
qdrŒo

;.&
{
:A3
-%Q#K/
K&)HI./)+6+.4/9(:8##%c=K&).T/K%,#
H^T9G=K&)
1.6.2. Bảo vệ điện ápnK&)./)"-+1t94/n6+#/2!&(+6+
.4/
a) Bảo vệ điện áp cực tiểun9(=K&)5]#"+.8##>?%E-
./)"-/K:./H5!,#%/)HI./)\:4+%T9G./)"-+6+#/2!
5]#"+.8;%/./)"-+@A:4+%.>E+=K&)/K:.7H>D//"#L.•
.>E+#%/7#9'-.2=K&)#"+.8/)"-.>E+#%/7#9'-(Mf/9(./)
"-;%i/.8+@A=K&)n
;.&
N+9(:!*#"+.8+B#%OA:• !A
%)5A!n
 •
;.&
qdr•o
2=K&);%<#"+.8#+%7.8=$%#%>?0#%$./)"-
;%i/.8-%K/%O%T./)"-.L%:N+
.:
&(%O%T./)"-+6+

Giáo trình Bảo vệ rơ le – Dự án RE II
{
;.&
qdrddo
2+%=K&);%<#"+.8#+%7.8=$%#%>?0#%$+e
#>T#6%>+"+#>?%E-#P0#A-%K/.K:=K !A%)5A!n

;.&
{
.:
qdrdto

;.&
{
:A3&'%(%
.1
:A3&'%(%
9(./)"-+6+.4/+1#%23!›#%/)# !"
#$%&'%(%i+%7.8=$%#%>?#4/%c+6++@A:4+%.>E+=K
&)
K&)=’T9G./)"-+6+.4/3CHQ/(%+%=K&)&D/=8
9f+i#:8#5*:4+%+@A%)#%*J9>E
1.6.3. Bảo vệ có hướng:
K&)+1%>D#"+.8;%/3!,#%/)56=/7.S/ !A#f
+@A9)+%-%A/cAHI./)&(./)"-+@A:4+%.>E+=K&)RHQn
#>?%E-.>?H`M+!+,-#h%A/-%RAq%$%dr|o0+K%A/#!#`:

d 
&A
t

d
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Trích đoạn Các loại rơle, sơ đồ nối rơle với máy biến dòng và dòngđiện thao tác Bảo vệ dòngđiện cực đại lựa chọn thiết bị BVDCĐ Bảo vệ chạm đất Bảo vệ đường dây trên không và đường dây cáp

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