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GIÁO TRÌNH

ĈRO˱ͥQJÿL͏n
B͡ môn Cung C̭SĈL͏n Trang 5
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FKXҭQKyDÿҥLOѭӧQJPүXKRһFÿҥLOѭӧQJFKXҭQ
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WKLӃWEӏÿR1KѭYұ\ÿӝFKtQK[iFFӫDWKLӃWEӏÿRÿѭӧFGLӉQWҧGѭӟLKLQKWKӭFVDLVӕ
1.1.KiLQLӋPYӅÿROѭӡQJÿLӋQ
7URQJWKӵFWӃFXӝFVӕQJTXiWUuQKFkQÿRÿRQJÿӃPGLӉQUDOLrQWөFYӟLPӑLÿӕL
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YӟLPӝWÿѫQYӏÿmÿѭӧFÿӏQKWUѭӟF
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KӓQJWURQJPҥFKÿLӋQ
ĈROѭӡQJOjTXiWUuQKVRViQKÿҥLOѭӧQJFKѭDELӃWYӟLÿҥLOѭӧQJÿmELӃWFQJ
ORҥLÿѭӧFFKӑQOjPPүXPүXQj\ÿѭӧFJӑLOjÿѫQYӏ

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FөWKӇ
'өQJFөÿR YjPүXÿR:
D'өQJFөÿR
&iFGөQJFөWKӵFKLӋQYLӋFÿRÿѭӧFJӑLOjGөQJFөÿRQKѭGөQJFөÿRGzQJÿLӋQ
$PSHPpWGөQJFөÿRÿLӋQiS9{QPpWGөQJFөÿRF{QJVXҩW2iWPpWYY
E0үXÿROjGөQJFөGQJÿӇNK{LSKөFPӝWÿҥLOѭӧQJYұWOêQKҩWÿӏQKFyWUӏVӕ
FKRWUѭӟFPүXÿRÿѭӧFFKLDOjPORҥLVDX

ĈRO˱ͥQJÿL͏n
B͡ môn Cung C̭SĈL͏n Trang 6
- /RҥLOjPPүXGQJÿӇNLӇPWUDFiFPүXÿRYjGөQJFөÿRNKiFORҥLQj\ÿѭӧF
FKӃWҥRYjVӱGөQJWKHRWLrXFKXҭQNӻWKXұWÿҧPEҧROjPYLӋFFKtQK[iFFDR
- /RҥLF{QJWiFÿѭӧFVӱGөQJÿROѭӡQJWURQJWKӵFWӃORҥLQj\JӗPQKyPVDX
0үXÿRYjGөQJFөÿRWKtQJKLӋP
0үXÿRYjGөQJFөÿRGQJWURQJVҧQ[XҩW
&iFSKѭѫQJSKiSÿR ÿѭӧFFKLDOjPORҥL
D3KѭѫQJSKiSÿRWUӵFWLӃS OjSKѭѫQJSKiSÿRPjÿҥLOѭӧQJFҫQÿRÿѭӧFVRViQK
WUӵFWLӃSYӟLPүXÿR
3KѭѫQJSKiSQj\ÿѭӧFFKLDWKjQKFiFKÿR
- 3KѭѫQJSKiSÿRÿӑFVӕWKҷQJ
-PKѭѫQJSKiSÿRVRViQKOjSKѭѫQJSKiSPjÿҥLOѭӧQJFҫQÿRÿѭӧFVRViQKYӟL
PүXÿRFQJORҥLÿmELӃWWUӏVӕ
9tGͭ:
'QJFҫXÿRÿLӋQÿӇÿRÿLӋQWUӣGQJFҫXÿRÿӇÿRÿLӋQGөQJYY
E3KѭѫQJSKiSÿRJLiQWLӃS ljSKѭѫQJSKiSÿRWURQJÿyÿҥLOѭӧQJFҫQÿRVӁÿѭӧF
WtQKUDWӯNӃWTXҧÿRFiFÿҥLOѭӧQJNKiFFyOLrQTXDQ
9tGͭ:
0XӕQÿRÿLӋQiSQKѭQJWDNK{QJFy9{QPpWWDÿRÿLӋQiSEҵQJFiFK
- 'QJÐPPpWÿRÿLӋQWUӣFӫDPҥFK

- 'QJ$PSHPpWÿRGzQJÿLӋQÿLTXDPҥFK
6DXÿyiSGөQJFiFF{QJWKӭFKRһFFiFÿӏQKOXұWÿmELӃWÿӇWtQKUDWUӏVӕÿLӋQiSFҫQ
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6DLVӕ
.KLÿRVӕFKӍFӫDGөQJFөÿRFNJQJQKѭNӃWTXҧWtQKWRiQOX{QFyVӵVDLOӋFKYӟLJLi
WUӏWKӵFFӫDÿҥLOѭӑQJFҫQÿR/ѭӧQJVDLOӋFKQj\JӑLOjVDLVӕ
6DLVӕJӗPORҥL
6DLV͙K͏WK͙QJ OjVDLVӕFѫEҧQPjJLiWUӏFӫDQyOX{QNK{QJÿәLKRһFWKD\ÿәL
FyTX\OXұW6DLVӕQj\YӅQJX\rQWҳFFyWKӇORҥLWUӯÿѭӧF
Nguyên nhân:
'RTXiWUuQKFKӃWҥRGөQJFөÿRQKѭPDViWNKҳFYҥFKWUrQWKDQJÿRYY
6DLV͙QJ̳XQKLrQ OjVDLVӕPjJLiWUӏFӫDQyWKD\ÿәLUҩWQJүXQKLrQGRVӵWKD\
ÿәLFӫDP{LWUѭӡQJErQQJRjLQJѭӡLVӱGөQJQKLӋWÿӝP{LWUѭӡQJWKD\ÿәLFKӏXҧQK
KѭӣQJFӫDÿLӋQWUѭӡQJWӯWUѭӡQJÿӝҭPiSVXҩWYY
Nguyên nhân:
- 'RQJѭӡLÿRQKuQOӋFKQKuQQJKLrQJÿӑFVDLYY

ĈRO˱ͥQJÿL͏n
B͡ môn Cung C̭SĈL͏n Trang 7
- 'QJF{QJWKӭFWtQKWRiQNK{QJWKtFKKӧSGQJF{QJWKӭFJҫQÿ~QJWURQJWtQK
WRiQ1KLӋWÿӝP{LWUѭӡQJWKD\ÿәLFKӏXҧQKKѭӣQJFӫDÿLӋQWUѭӡQJWӯWUѭӡQJÿӝҭPiS
VXҩWYY
3KѭѫQJSKiSKҥQFKӃVDLVӕ
ĈӇKҥQFKӃVDLVӕWURQJWӯQJWUѭӡQJKӧSFyFiFSKѭѫQJSKiSVDX
  ĈӕL YӟL VDL Vӕ KӋ WKӕQJ WLӃQ KjQK ÿR QKLӅX OҫQ Yj Oҩ\JLi WUӏ WUXQJ EuQK FӫD
chúng.
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4XDQKӋJLӳDVDLVӕWѭѫQJÿӕLYjVDLVӕTXLÿәL
d
dmdm
qd
KA
A
A
A
A
A
A
**%100. '

'

'

J
(1.4)
dm
d
A
A
K
OjKӋVӕVӱGөQJWKDQJÿR.
d
d 1)
1ӃX.
d
FjQJJҫQEҵQJWKuÿҥLOѭӧQJÿRJҫQEҵQJJLӟLKҥQÿR'A càng bé thì phép
ÿRFjQJFKtQK[iF7K{QJWKѭӡQJSKpSÿRFjQJFKtQK[iFNKL.
d
t 1/2.
9tGө 0ӝWGzQJÿLӋQFyJLiWUӏWKӵFOj$'QJ$PSHPpWFyJLӟLKҥQÿR$ÿӇ
ÿRGzQJÿLӋQQj\.ӃWTXҧÿRÿѭӧF$
7tQKVDLVӕWX\ӋWÿӕLVDLVӕWѭѫQJÿӕLVDLVӕTXLÿәL
*LҧL
6DLVӕWX\ӋWÿӕL

ĈRO˱ͥQJÿL͏n
B͡ môn Cung C̭SĈL͏n Trang 8
'A =~A
1

-A~= 5 - 4,95 = 0,05 A
6DLVӕWѭѫQJÿӕL
%100.
A
A
A
'
'
KRһF
%1%100.
5
05,0
%100.
1

'
'
A
A
A
6DLVӕTXLÿәL
%5,0%100*
10
05,0
%100.
'

dm
qd
A

A
J
%LӉXGLӉQVӕÿR
.ӃWTXҧÿRÿѭӧFELӇXGLӉQGѭӟLGҥQJ
0
X
X
A
và ta có X = A.X
0
(1.5)
9tGө , $WKuĈҥLOѭӧQJÿROjGzQJÿLӋQ,
ĈѫQYӏÿROj$PSH$
&RQVӕNӃWTXҧÿROj
+ӋÿѫQYӏÿR
*LӟLWKLӋXKӋ6, 6\VWqPH,QWHUQDWLRQDOG8QLWpVKӋWKӕQJÿѫQYӏÿROѭӡQJ
WK{QJGөQJQKҩWKӋWKӕQJQj\TXLÿӏQKFiFÿѫQYӏFѫEҧQFKRFiFÿҥLOѭӧQJVDX
- ĈӝGjLWtQKEҵQJPpWP
- .KӕLOѭӧQJWtQKEҵQJNLO{JDPNJ
- 7KӡLJLDQ WtQKEҵQJJLk\V
- 'zQJÿLӋQWtQKEҵQJ$PSH$
%ӝLYjѭӟFVӕFӫDÿѫQYӏFѫ EҧQ
%ӝLVӕ ѬӟFVӕ
+ Tiga (T): 10
12
+ Mili (m): 10
-3

+ Giga (G): 10
9

+ Micro (P): 10
-6
+ Mêga (M): 10
6
+ Nano (n):10
-9
+ Kilô (K): 10
3
+ Pico (p):10
-12
7URQJÿy;OjÿҥLOѭӧQJÿR
X
0
OjÿѫQYӏ ÿR

ĈRO˱ͥQJÿL͏n
B͡ môn Cung C̭SĈL͏n Trang 9
&Æ8+Ӓ,9¬%¬,7Ұ3
A. &kXKӓLWUҳFQJKLӋP
ĈӑFNӻFiFFkXKӓLFKӑQYjW{ÿHQêWUҧOӡLÿ~QJQKҩWYjRFiF{ӣFiFFӝWWѭѫQJ
ӭQJ
TT 1ӝLGXQJFkXKӓL abc
d
1.1. *LiWUӏEҵQJKLӋXVӕJLӳDJLiWUӏÿ~QJFӫDÿҥLOѭӧQJFҫQ
ÿRYjJLiWUӏÿRÿѭӧFWUrQPһWÿӗQJKӗÿRÿѭӧFJӑLOj
a. 6DLVӕSKө
b. 6DLVӕFѫEҧQ
c. 6DLVӕWX\ӋWÿӕL
G6DLVӕWѭѫQJÿӕL
#ð #ð #ð

#ð
1.2.
7ӹ OӋ JLӳD VDL Vӕ WX\ӋW ÿӕL Yj JLi WUӏ WKӵF FҫQ ÿR WtQK
WKHRÿѭӧFJӑLOj
a. 6DLVӕWѭѫQJÿӕL
b. 6DLVӕSKө
c. 6DLVӕFѫEҧQ
d. 7ӹOӋSKҫQWUăPFӫDVDLVӕWX\ӋWÿӕL
#ð #ð #ð
#ð
1.3 .KLÿRÿLӋQiS[RD\FKLӅX9YӟLGөQJFөÿRFyVDLVӕ
WѭѫQJÿӕLWKuVDLVӕWX\ӋWÿӕLOӟQQKҩWFyWKӇFyYӟL
GөQJFөOj
a. 10V;
b. 2,2V;
c. 3,3V;
d. 1,1V.
#ð #ð #ð
#ð
%%jLWұS
1.4. 1rXFiFÿӏQKQJKƭDYӅÿROѭӡQJ.
1.53KѭѫQJSKiSÿROjJu"&yPҩ\SKѭѫQJSKiSÿR"
1.6ĈѫQYӏÿROjJu"7KӃQjRJӑLOjÿѫQYӏWLrXFKXҭQ"
1.7'өQJFөÿROjJu"
1.86DLVӕOjJu"&yPҩ\ORҥLVDLVӕ"3KѭѫQJSKiSKҥQFKӃVDLVӕ"&iFKWtQKVDLVӕ"

ĈRO˱ͥQJÿL͏Q
B͡ môn Cung C̭SĈL͏n Trang 10
&+ѬѪ1*,,
0Ӝ76Ӕ&Ѫ&Ҩ8Ĉ2&+ӌ7+ӎ.,0

*LӟLWKLӋX
+LӋQQD\NKRDKӑFNӻWKXұWUҩWSKiWWULӇQ1JѭӡLWDÿmFKӃWҥRUDÿѭӧFQKLӅXWKLӃWEӏ
ÿROѭӡQJÿLӋQWӱFKӍWKӏNӃWTXҧÿREҵQJKLӋQVӕFyÿӝFKtQK[iFFDR7X\QKLrQFiFWKLӃW
EӏÿROѭӡQJVӱGөQJFѫFҩXFKӍWKӏNӃWTXҧÿREҵQJNLPYүQÿѭӧFVӱGөQJUҩWSKәELӃQ
WURQJFiF[tQJKLӋSWUѭӡQJKӑFFNJQJQKѭWURQJFiFSKzQJWKtQJKLӋPYuWtQKѭXYLӋWFӫD
Qy&iFWKLӃWEӏÿROѭӡQJVӱGөQJFѫFҩXÿRFKӍWKӏNLPÿѭӧFGQJQKLӅXQKҩWOj9{QPpW
Yj$PSHPpWKѫQWKӃQӳDFiFFѫFҩXQj\WKDRWiFVӱGөQJÿѫQJLҧQYjJLiWKjQKFNJQJ
UҿKѫQUҩWQKLӅXVRYӟLFiFWKLӃWEӏÿROѭӡQJFKӍWKӏNӃWTXҧÿROѭӡQJEҵQJKLӋQVӕ9uYұ\
QJѭӡLF{QJQKkQFҫQKLӇXU}FҩXWҥRQJX\rQOêKRҥWÿӝQJFNJQJQKѭVӱGөQJWKjQKWKҥR
FiFFѫFҩXÿRFKӍ WKӏNLP
1JX\rQWҳFFKXQJFӫDFiFORҥLPi\ÿRFKӍWKӏNLP
+LӋQQD\WDFKӍKӑFFiFFѫFҩXFKӍWKӏNӃWTXҧÿREҵQJNLPFzQFiFFѫFҩXFKӍWKӏ
NӃWTXҧÿREҵQJVӕÿѭӧFÿӅFұSWURQJSKҫQWKLӃWEӏÿROѭӡQJFKӍWKӏVӕ
ĈӕLYӟLFiFFѫFҩXFKӍWKӏNLPNKLWKӵFKLӋQPӝWSKpSÿROX{QWXkQWKHRWUuQKWӵ
sau:
7tQKLӋXFӫDÿҥLOѭӧQJFҫQÿRÿѭӧFÿѭDYjRPҥFKÿRYjÿѭӧFELӃQÿәLWKjQKÿҥL
OѭӧQJÿLӋQÿҥLOѭӧQJÿLӋQQj\ÿѭӧFÿѭDYjRFѫFҩXÿRYjNӃWTXҧÿRÿѭӧFÿѭDUDNKӕL
FKӍWKӏVѫÿӗÿѭӧFKuQKWKjQK
2.1.1. SѫÿӗNKӕL


+uQK6ѫÿӗNKӕLFӫDFѫFҩXÿR
&KX\ӇQÿәLVѫFҩSOjPQKLӋPYөELӃQÿәLFiFÿҥLÿRWKjQKWtQKLӋXÿLӋQ
ĈyOjNKkXTXDQWUӑQJQKҩWFӫDWKLӃWEӏÿR
0ҥFKÿROjNKkXJLDF{QJWK{QJWLQÿRVDXFKX\ӇQÿәLVѫFҩSOjPQKLӋP
YөWtQKWRiQYjWKӵFKLӋQWUrQVѫÿӗPҥFK0ҥFKÿRWKѭӡQJOjPҥFKÿLӋQWӱYL[ӱOêÿӇ
QkQJFDRÿһFWtQKFӫDGөQJFө ÿR
&ѫFҩXFKӍWKӏÿROjNKkXFXӕLFQJFӫDGөQJFөWKӇKLӋQNӃWTXҧÿRGѭӟL
GҥQJFRQVӕYӟLÿѫQYӏ
&yFiFKWKӇKLӋQNӃWTXҧÿR

+ &KӍWKӏEҵQJNLP
&KӍWKӏEҵQJWKLӃWEӏWӵJKL
+ &KӍWKӏGѭӟLGҥQJFRQVӕ
1KѭYұ\FѫFҩXÿREDRJӗPFySKҫQWƭQKYjSKҫQÿӝQJ
ChuyӇQÿәLVѫFҩp MҥFKÿR
&ѫFҩu chӍ thӏ

ĈRO˱ͥQJÿL͏Q
B͡ môn Cung C̭SĈL͏n Trang 11
3KҫQWƭQKFyQKLӋPYөELӃQÿәLÿLӋQQăQJÿѭDYjRWKjQKFѫQăQJWiFGөQJ
OrQSKҫQÿӝQJ
3KҫQ ÿӝQJ JҳQ OLӅQ YӟL NLP JyF TXD\ FӫD NLP[iF ÿӏQK WUӏ Vӕ FӫD ÿҥL
OѭӧQJÿѭӧFÿѭDYjRFѫFҩXÿR
.KӕLFKӍWKӏ
2.1.2. Nguyên lý:
9ӟLFiFORҥLPi\ÿR FKӍWKӏNLPQrXWUrQWX\YӅFҩXWU~FFyNKiFQKDXQKѭQJFK~QJ
FyFKXQJPӝWQJX\rQWҳFVDX
.KLGzQJÿLӋQFKҥ\WURQJWӯWUѭӡQJVӁVLQKUDPӝWOӵFÿLӋQWӯOӵFQj\VӁVLQKUD
PӝWP{PHQTXD\OjPTXD\NLPFKӍWKӏPӝWJyFD, góc quay D FӫDNLPOX{QWӹOӋYӟLÿҥL
OѭӧQJFҫQÿREDQÿҫXQrQQJѭӡLWDVӁÿRJyFOӋFKQj\ÿӇELӃWJLiWUӏFӫDÿҥLOѭӧQJFҫQÿR
&ѫFҩXÿRNLӇXWӯÿLӋQ
2.2.1. .êKLӋX
2.2.2. 6ѫÿӗFҩXWҥR
.KXQJTXD\NKXQJTXD\EҵQJQK{PKuQKFKӳQKұWWUrQNKXQJ FyTXҩQGk\ÿӗQJ
EӑFYHFQL7RjQEӝNKӕLOѭӧQJNKXQJTXD\SKҧLFjQJQKӓFjQJWӕWÿӇVDRFKRP{PHQ
TXiQWtQKFjQJQKӓFjQJWӕW7RjQEӝNKXQJTXD\ÿѭӧFÿһWWUrQWUөFTXD\KRһFWUHREӣL
dây treo.
1DPFKkPYƭQKFӱXNKXQJTXD\ÿѭӧFÿһWJLӳDKDLFӵFWӯ1-S FӫDQDPFKkP
YƭQKFӱX
Hình 2.2a: Ký hiӋXFѫFҩu tӯÿLӋn

Hình 2.2b: Ký hiӋXFѫFҩu tӯÿLӋn
NS
Khe hӣ cӵctӯ
Lӓi sҳt non
Ĉӕi trӑng
Cuӝn dây
Nam châm
Cӵc tӯ
Kim chӍ thӏ
Lò xo
x
+uQK6ѫÿӗ cҩu tҥRFѫFҩXÿRNLӇu tӯ

ĈRO˱ͥQJÿL͏Q
B͡ môn Cung C̭SĈL͏n Trang 12
/}LVҳWQRQKuQKWUөQҵPWURQJNKXQJTXD\WѭѫQJÿӕLÿӅX
.LPFKӍWKӏÿѭӧFJҳQFKһWWUrQWUөFTXD\KRһFGk\WUHR3KtDVDXNLPFKӍWKӏFy
PDQJÿӕLWUӑQJÿӇVDRFKRWUӑQJWkPFӫDNLPFKӍWKӏQҵPWUrQWUөFTXD\KRһFGk\WUHR
+ Lò xRÿӕLNKiQJNLӇPVRiWKRһFGk\WUHRFyQKLӋPYөNpRNLPFKӍWKӏYӅYӏWUt
EDQÿҫXÿLӇPYjNLӇPVRiWVӵTXD\FӫDNLPFKӍWKӏ
2.2.3. 6ѫÿӗQJX\rQOê
1JX\rQOêKRҥWÿӝQJ.KLFyGzQJÿLӋQFҫQÿR,ÿLYjRFXӝQGk\WUrQNKXQJ
TXD\VӁWiFGөQJYӟLWӯWUѭӡQJӣNKHKӣWҥRUDOӵFÿLӋQWӯ)
F = N.B.l.L (2.1)
7URQJÿy1VӕYzQJGk\TXҩQFӫDFXӝQGk\
%PұWÿӝWӯWK{QJ[X\rQTXDNKXQJGk\
/FKLӅXGjLFӫDNKXQJGk\
,FѭӡQJÿӝGzQJÿLӋQ
/ӵF ÿLӋQWӯQj\VӁVLQKUDPӝWP{PHQTXD\0
q

:
NBILb
b
FM
q

2
2
(2.2)
7URQJÿy EOjEӅUӝQJFӫDNKXQJGk\
Yj/E 6OjGLӋQWtFKFӫDNKXQJGk\
Nên: M
q
= N.B.S.I (2.3)
Mômen quay này làm pKҫQÿӝQJPDQJNLPÿRTXD\ÿLPӝWJyFD QjRÿyYjOz[R
ÿӕLNKiQJEӏ[RҳQOҥLWҥRUDP{PHQÿӕLNKiQJ0
ÿN
WӹOӋYӟLJyFTXD\D.
M
ÿN
= K.D .OjÿӝFӭQJFӫDOz[R
.LPFӫDFѫFҩXVӁÿӭQJOҥLNKLKDLP{PHQWUrQEҵQJQKDX
M
q
= M
ÿN

N.B.S.I = K.D (2.4)
b
F

)µ
N
S
+uQK6ѫÿӗ nguyên lý
ҩӇ
I
K
BSN
. 
D

ĈRO˱ͥQJÿL͏Q
B͡ môn Cung C̭SĈL͏n Trang 13
ĈһW C = const

D = C.I (2.5)
&JӑLOjÿӝQKҥ\FӫDFѫFҩXÿRWӯÿLӋQ$PP&KRELӃWGzQJÿLӋQFҫQWKLӃWFKҥ\
TXDFѫFҩXÿRÿӇNLPÿROӋFKÿѭӧF PPKD\YҥFK
.ӃWOXұQ TXDELӇXWKӭFWUrQWDWKҩ\UҵQJJyFTXD\D FӫDNLPÿRWӹOӋYӟLGzQJÿLӋQ
FҫQÿRYjÿӝQKҥ\FӫDFѫFҩXÿRGzQJÿLӋQYjÿӝQKҥ\FjQJOӟQWKuJyFTXD\FjQJOӟQ
7ӯJyFD FӫDNLPWDVX\UDJLiWUӏFӫDÿҥLOѭӧQJFҫQÿR
ĈһFÿLӇPYjӭQJGөQJ
DĈһFÿLӇP
- ĈӝQKҥ\FDRQrQFyWKӇÿRÿѭӧFFiFGzQJÿLӋQPӝWFKLӅXUҩWQKӓWӯ
-12
y10
-14
).
- 7LrXWKөQăQJOѭӧQJÿLӋQtWQrQÿӝFKtQK[iFUҩWFDR
- &KӍÿRÿѭӧFGzQJYjiSPӝWFKLӅX

- .KҧQăQJTXiWҧLNpPYuNKXQJGk\TXD\QrQFKӍTXҩQÿѭӧFGk\FӥQKӓ
- &KӃWҥRNKyNKăQJLiWKjQKÿҳW
0X͙QÿRÿ˱ͫFFiFÿ̩LO˱͕QJ[RD\FKL͉XSK̫LTXDF˯F̭XQ̷QGzQJ
EӬQJGөQJ
6ҧQ[XҩWFiFGөQJFөÿR
- ĈRGzQJÿLӋQPLOL$PSHPpW$PSHPpW
- ĈRÿLӋQiSPLOL9{QPpW9{QPpW
- ĈRÿLӋQWUӣ{PPpW
2.3. &ѫFҩXÿRNLӇXÿLӋQWӯ
2.3.1.Ký KLӋX
constC
K
BSN



Hình 2.5: ký hiӋXFѫFҩXÿRÿLӋn tӯ

ĈRO˱ͥQJÿL͏Q
B͡ môn Cung C̭SĈL͏n Trang 14
2.3.2.6ѫÿӗFҩXWҥR
D3KҫQWƭQKJӗPFXӝQGk\SKҫQWƭQKWUzQKRһFSKҷQJNK{QJFyO}LWKpS
E3KҫQÿӝQJJӗPOiWKpSQRQKuQKEiQQJX\ӋWJҳQOӋFKWkPWUrQWUөF7UrQWUөF
FzQFyOz[RÿӕLNKiQJNLPYjEӝSKұQFҧQGӏXNLӇXNK{QJNKt
2.3.3.1JX\rQOêKRҥWÿӝQJ
.KLFyGzQJÿLӋQFҫQÿR,ÿLYjRFXӝQGk\SKҫQWƭQKWKuQyVӁWUӣWKjQKPӝWQDP
FKkPÿLӋQYjSKLӃQWKpSVӁEӏK~WYjRUmQK/ӵFK~WQj\WҥRUDPӝWP{PHQTXD\
WUөF

2

1
IKM
q

(2.6)
'ѭӟLWiFGөQJFӫD0
q
NLPVӁTXD\PӝWJyFD/z[RVRVӁEӏ[RҳQGRÿyVLQKUD
P{PHQÿӕLNKiQJWӹOӋYӟLJyFTXD\D.
M
ÿN
=K
2
.D (2.7)
.LPVӁQJѭQJTXD\NKLP{PHQWUrQFkQEҵQJQJKƭDOj

2
2
1
2
2
1
I
K
K
KIK 
DD
(2.8)
7KӵFUDӣYӏWUtFkQEҵQJNLPFKѭDGӯQJOҥLQJD\PjGDRÿӝQJTXDOҥL[XQJTXDQK
YӏWUtÿyQKѭQJQKӡFyEӝFҧQGӏXEҵQJNK{QJNKtVӁGұSWҳWTXiWULQKGDRÿӝQJQj\

2.3.4.ĈһFÿLӇPYjӭQJGөQJ
DĈһFÿLӇP
- &ҩXWҥRÿѫQJLҧQGӉFKӃWҥRJLiWKjQKUҿ
- ĈRÿѭӧFÿLӋQPӝWFKLӅXYj[RD\FKLӅX
Hình 2.6: &ѫFҩXÿRNLӇXÿLӋn tӯ
1. Cuӝn dây phҫQWƭQK 4. Trөc quay.
2 Rãnh hҽp. 5. Bӝ cҧn dӏu kiӇu không khí
3PhiӃn thép /z[Rÿӕi kháng.
6
1
2
3
5
4
0
1
2
3

ĈRO˱ͥQJÿL͏Q
B͡ môn Cung C̭SĈL͏n Trang 15
- .KҧQăQJTXiWҧLWӕWYuFyWKӇFKӃWҥRFXӝQGk\SKҫQWƭQKYӟLWLӃWGLӋQGk\OӟQ
- 'RFXӝQGk\FyO}LOjNK{QJNKt QrQWӯWUѭӡQJ\ӃXYuYұ\ÿӝQKҥ\NpPYjFKӏX
ҧQKKѭӣQJFӫDWӯWUѭӡQJQJRjL
- &ҩSFKtQK[iFWKҩS
- 7KDQJFKLDNK{QJÿӅX
EӬQJGөQJ
- &KӃWҥRFiFGөQJFөÿRWK{QJGөQJ9{QPpW$PSHPpWÿR$&
- 'QJWURQJVҧQ[XҩWYjSKzQJWKtQJKLӋP
&ѫFҩXÿRNLӇXÿLӋQÿӝQJ

2.4.1 êKLӋX
2.4.2.6ѫÿӗFҩXWҥR
&ѫFҩXÿRÿLӋQÿӝQJ+uQKJӗPFyFXӝQGk\SKҫQWƭQKÿѭӧFFKLDWKjQK
SKҫQ QӕL WLӃS QKDX ÿӇ WҥR UD Wӯ WUѭӡQJ ÿӅX NKL Fy GzQJ ÿLӋQ FKҥ\ TXD 3KҫQ ÿӝQJ Oj
Hình 2.7: Ký hiӋXFѫFҩXÿRÿLӋQÿӝng
)
2




I
1
I
2
)
1
1
2
Hình 2.8: Ký hiӋXFѫFҩXÿRÿLӋQÿӝng
1- CuӝQGk\WƭQK
2- CuӝQGk\ÿӝng.
I
1
- 'zQJÿLӋn chҥy trong cuӝn dây 1

ĈRO˱ͥQJÿL͏Q
B͡ môn Cung C̭SĈL͏n Trang 16
NKXQJGk\ÿһWWURQJFXӝQGk\WƭQKYjJҳQWUrQWUөFTXD\+uQKGiQJFXӝQGk\FyWKӇ
WUzQKRһFYX{QJ&ҧSKҫQÿӝQJYjSKҫQWƭQKÿѭӧFEӑFNtQEҵQJPjQFKҳQWӯÿӇWUiQKҧQK

KѭӣQJFӫDWӯWUѭӡQJQJRjLÿӃQVӵOjPYLӋFFӫDFѫFҩXÿR
2.4.3.Nguyên OêKRҥWÿӝQJ
.KLFyGzQJÿLӋQ,
1
,I
2
'&KRһF$&ÿLYjRFXӝQGk\GLÿӝQJYjFӕÿӏQKVӁWҥRUD
mômen quay:
M
q
= k
q
I
1
I
2
GzQJÿLӋQ'&
+RһF
)
1
(
0
21
³

T
q
dtii
T
kqM

GzQJÿLӋQ$&
9ұ\JyFTXD\
21
II
k
k
c
q

D
KRһF
)
1
(
2
0
1
dtii
Tk
k
T
c
q
³

D
K
c
OjKҵQJVӕ[RҳQFӫDOz[R
1ӃX

const
k
k
c
q

WKuWKDQJÿRWX\ӃQWtQKWKHR,
1
,I
2
2.4.4.ĈһFÿLӇPYjӭQJGөQJ
&ѫFҩXÿRÿLӋQÿӝQJFyWKӇGQJWURQJPҥFKPӝWFKLӅXYj[RD\FKLӅXWKDQJÿR
NK{QJÿӅXFyWKӇGQJÿӇFKӃWҥR9{QPpW$PSHPpWYj2iWPpWFyÿӝFKtQK[iFFDRYӟL
FҩSFKtQK[iFy 1KѭӧFÿLӇPOjWLrXWKөF{QJVXҩWOӟQ
&Æ8+Ӓ,9¬%¬,7Ұ3
$&Æ8+Ӓ,&Ӫ1*&Ӕ%¬,
ĈӑFNӻFiFFkXKӓLFKӑQFkXWUҧOӡLÿ~QJQKҩWYjW{ÿHQ{ÿmFKӑQYjRFӝWWѭѫQJ
ӭQJ
TT 1ӝLGXQJFkXKӓL
a
bcd
2.1.
&ѫFҩXÿRWӯÿLӋQÿRÿѭӧFFiFÿҥLOѭӧQJ:
a. ĈLӋQPӝWFKLӅX
b. ĈLӋQ[RD\FKLӅX
c. ĈLӋQ[RD\FKLӅXPӑLWҫQVӕ
d. &ҧPӝWFKLӅXOүQ[RD\FKLӅX
#ð
#ð #ð #ð
2.2. &ѫFҩXÿRWӯÿLӋQWKDQJÿRÿѭӧFFKLD:

a. ĈӅXWX\ӃQWtQK
b. 7ӹOӋWKHRKjPORJDULW
#ð
#ð #ð #ð

ĈRO˱ͥQJÿL͏Q
B͡ môn Cung C̭SĈL͏n Trang 17
c. 7ӹOӋEұF
d. 7ӹOӋWKHRKjPPNJ
2.3
ĈһFÿLӇPFKtQK FӫD  ORҥL Fѫ FҩX ÿR NLӇX ÿLӋQ Wӯ NLӇX
ÿLӋQÿӝQJYjNLӇXWӯÿLӋQOj
a. .LӇXÿLӋQWӯ3KpSÿRFKtQK[iFYjÿӝQKҥ\FDR
b. .LӇXÿLӋQÿӝQJ3KpSÿRFKtQK[iFYjÿӝQKҥ\FDR
c. .LӇXWӯÿLӋQ3KpSÿRFKtQK[iFYjÿӝQKҥ\FDR
d. %DNLӇXOjQKѭQKDXNK{QJNKiFELӋW
#ð #ð #ð #ð
2.4
ĈӇPӣUӝQJJLӟLKҥQÿRFKRFѫFҩXÿRÿLӋQWӯÿӇÿRÿLӋQ
iS[RD\FKLӅXWUrQ9SKҧLGQJ:
a. ĈLӋQWUӣSKөPҳFQӕLWLӃS
b. ĈLӋQWUӣSKөPҳFVRQJVRQJ
c. %LӃQiSÿROѭӡQJ
d. %LӃQGzQJÿROѭӡQJ.
#ð #ð #ð #ð
2.5
.KLÿRÿLӋQWUӣ*yFTXD\FӫDNLPFjQJOӟQWKuNӃWOXұQ:
a. ĈLӋQWUӣUҩWOӟQ
b. ĈLӋQWUӣFjQJOӟQ
c. ĈLӋQWUӣFjQJQKӓ

d. 7XǤORҥLPi\ÿR
#ð #ð #ð #ð
2.6
.KLÿRÿLӋQWUӣEҵQJPi\ÿRFKӍWKӏNLP7UӏVӕSKҧLÿѭӧF
ÿӑFWUӏWӯ:
a. 3KҧLTXDWUiL
b. TráLTXDSKҧL
c. *LӳDUDELrQ
d. 7ҥLYӏWUtNLPGӯQJOҥL
#ð #ð #ð #ð

ĈRO˱ͥQJÿL͏Q
B͡ môn Cung C̭SĈL͏n Trang 18
.
2.7 .KLÿRGzQJÿLӋQKRһFÿLӋQ iS*yFTXD\ FӫDNLP FjQJ
OӟQWKuNӃWOXұQ
a. 7UӏVӕFjQJQKӓ
b. 7UӏVӕQKӓUҩW
c. 7UӏVӕFjQJOӟQ
d. 7XǤORҥL
#ð
#ð #ð #ð
2.8 .KLÿRGzQJÿLӋQKRһFÿLӋQiSEҵQJPi\ÿRFKӍWKӏNLP
7UӏVӕSKҧLÿѭӧFÿӑFWUӏWӯ
a. 3KҧLTXDWUiL
b. 7UiLTXDSKҧL
c. *LӳDUDELrQ
d. 7ҥLYӏWUtNLPGӯQJOҥL
#ð
#ð #ð #ð

%&kXKӓL
1. 1rXQJX\rQOêOjPYLӋFFӫDPi\ÿRFKӍWKӏNLPYjFiFFKLWLӃWFKXQJFӫDPi\ÿR
FKӍWKӏNLP
2. 1rXFҩXWҥRQJX\rQOêKRҥWÿӝQJYjÿһFÿLӇPӭQJGөQJFӫDFiFFKӍFiFFѫFҩX
ÿRWӯÿLӋQÿLӋQWӯÿLӋQÿӝQJ
7+Ӵ&+¬1+48$16È71+Ұ1%,ӂ79ӄ&Ҩ87Ҥ29¬ĈҺ&Ĉ,ӆ0&Ӫ$
&È&&Ѫ&Ҩ8Ĉ27+Ӵ&+¬1+7Ҥ,/Ӟ3
1. &KRKӑFVLQKTXDQViWYjQKұQELӃWWPӝWVӕFѫFҩXÿR WKѭӡQJGQJ
yêu cҫX :
- 9LӃWWrQFiFFѫFҩXÿR
- 1rXF{QJGөQJYjQJX\rQOêOjPYLӋFFӫDFiFORҥLFѫFҩXÿR ÿmÿѭӧFTXDQViW
1rXQKӳQJÿLӇPJLӕQJYjNKiFQKDXFӫDFiFFѫFҩXÿRÿmÿѭӧFTXDQViW.
1rXӭQJGөQJFӫDFiFFѫFҩXÿRÿyYjRFiFORҥLGөQJFөÿR
- 3KkQORҥLFiFcѫFҩXÿR ÿmÿѭӧFTXDQViWWKHRWӯQJQKyP
+ Nhóm FѫFҩXÿRÿLӋQÿӝQJ
+ Nhóm FѫFҩXÿRWӯÿLӋQ
+ Nhóm FѫFҩXÿRÿLӋQWӯ

ĈRO˱ͥQJÿL͏Q
B͡ môn Cung C̭SĈL͏n Trang 19
+ Nhóm FѫFҩXÿRFҧPӭQJ
/jPFiFEjLWұSWҥLOӟS
%%jLWұS
1rXFiFÿӏQKQJKƭDYӅÿROѭӡQJ
3KѭѫQJSKiSÿROjJu"&yPҩ\SKѭѫQJSKiSÿR"
ĈѫQYӏÿROjJu"7KӃQjRJӑLOjÿѫQYӏWLrXFKXҭQ"
'өQJFөÿROjJu"
6DLVӕOjJu"&yPҩ\ORҥLVDLVӕ"3KѭѫQJSKiSKҥQFKӃVDLVӕ"&iFKWtQKVDLVӕ"

ĈRO˱ͥQJÿL͏Q

%͡P{Q&XQJ&̭SĈL͏Q Trang 20
&+ѬѪ1*,,,
Ĉ2&È&ĈҤ,/ѬӦ1*Ĉ,ӊ1&Ѫ%Ҧ1
*LӟLWKLӋX
7URQJTXiWUuQKOҳSUiSEҧRGѭӥQJVӳDFKӳDYjYұQKjQKFiFPҥFKÿLӋQKRһFKӋ
WKӕQJÿLӋQÿzLKӓLQJѭӡLF{QJQKkQSKҧLQҳPÿѭӧFFiFWK{QJVӕFӫDFiFÿҥLOѭӧQJFѫ
EҧQWURQJPҥFKÿLӋQPҥQJÿLӋQKRһFKӋWKӕQJÿLӋQ7ӯÿyÿѭDUDSKѭѫQJiQOҳSÿһWEҧR
GѭӥQJVӱDFKӳDYjYұQKjQKPҥFKPҥQJKRһFKӋWKӕQJÿLӋQWӕLѭXQKҩWÿӗQJWKӡLÿҧP
EҧRDQWRjQFKRQJѭӡLYjWKLӃWEӏ0XӕQYұ\QJѭӡLF{QJQKkQÿLӋQSKҧLQҳPÿѭӧFFiF
SKѭѫQJSKiSÿRYjNLӇPWUDFiFÿҥLOѭӧQJFѫEҧQÿyPӝWFiFKQKXҫQQKX\ӉQYjFyQKѭ
Yұ\PӟLQkQJFDRÿѭӧFFKҩWOѭӧQJFӫDPҥFKPҥQJÿLӋQYjKӋWKӕQJÿLӋQ
ĈRGzQJÿLӋQ
ĈRGzQJÿLӋQPӝWFKLӅX'&
D'өQJFөÿRGөQJFөÿӇÿRGzQJÿLӋQÿӑFWKҷQJQJѭӡLWDGQJ$PSHPpW
.êKLӋX
b. 3KѭѫQJSKiSÿR
.KLÿR$PSHPpWÿѭӧFPҳFQӕLWLӃSYӟLSKөWҧ,KuQK
Ta có: R
Wÿ
= R
t
+ R
m
7URQJÿy
R
m
OjÿLӋQWUӣWURQJFӫD$PSHPpW Jk\VDLVӕ
0һWNKiFNKLÿR$PSHPpWWLrXWKөPӝWOѭӧQJF{QJVXҩW
mA
RIP

2

.
7ӯÿyÿӇSKpSÿRÿѭӧFFKtQK[iFWKu R
m
SKҧLUҩWQKӓ
F0ӣUӝQJJLӟLKҥQÿRFKR$PSHPpWWӯÿLӋQ
.KLGzQJÿLӋQFҫQÿRYѭӧWTXiJLӟLKҥQÿRFӫDFѫFҩXÿRQJѭӡLWDPӣUӝQJWKDQJ
ÿREҵQJFiFKPҳFQKӳQJÿLӋQWUӣVRQJVRQJYӟLFѫFҩXÿRJӑLOj6KXQWÿk\OjSKѭѫQJ
SKiSSKkQPҥFK
Ta có: I
S
R
S
= I
A
R
m
hay
S
m
A
S
R
R
I
I

(3.1)
R

m:
ÿLӋQWUӣWURQJFӫDFѫFҩXÿR
R
S
: ÿLӋQWUӣFӫD6KXQW
A
I
phө tҧi
A
R
t
R
m
x
x
U
Hình 3.1: Vѫÿӗ mҳcAmpemét
-
+
-
+

ĈRO˱ͥQJÿL͏Q
%͡P{Q&XQJ&̭SĈL͏Q Trang 21
7ӯWDVX\UD
S
Sm
A
AS
R

RR
I
II 


Vì: I = I
A
+ I
S
OjGzQJÿLӋQFҫQÿRQrQWDFy
S
m
S
Sm
A
R
R
R
RR
I
I


1
(3.2)
ĈһW
S
m
i
R

R
n  1
Ta suy ra I = n
i
I
A
S
m
i
R
R
n  1(
OjEӝLVӕFӫD6KXQW &iFKWtQKÿLӋQWUӣ6KXQW
n
i
: cho ELӃWNKLFyPҳF6KXQWWKuWKDQJÿRFӫD$PSHPpWÿѭӧFPӣUӝQJQ
i
OҫQVRYӟL
O~FFKѭDPҳF6KXQW
7ӯWDWKҩ\QӃX5
S
FjQJQKӓVRYӟL5
m
WKuWKDQJÿRÿѭӧFPӣUӝQJFjQJOӟQ
ĈLӋQWUӣVKXQWFyWKӇWtQKWKHRFiFKVDX
max.tai
max.
*
A
mA

S
II
RI
R


(*)
7URQJÿy,
WҧL
OjGzQJÿLӋQTXDWҧL
1

i
m
S
n
R
R
 $PSHPpW ÿѭӧF PҳF QKLӅX ÿLӋQ WUӣ 6KXQW NKiF QKDX ÿӇ Fy QKLӅX WҫPÿR NKiF
QKDXQKѭKuQKYӁ+uQK
Hình 3.26ѫÿӗ mҳFÿLӋn trӣ Shunt
ÿӇ ӣ ӝ iӟih ÿ
C
I
S
Shunt
I
A
R
S

I
R
m
R
1
R
3
2
3
R
2
1

ĈRO˱ͥQJÿL͏Q
%͡P{Q&XQJ&̭SĈL͏Q Trang 22
&yWKӇGQJFiFKFKX\ӇQÿәLWҫPÿRWKHRNLӇX6KXQW$\UWRQ(Hình 3.3):
0ҥFKÿRNLӇX6KXQW$\UWRQFyWҫPÿR
.KLNKyD.ӣYӏWUtWҫPÿRQKӓQKҩW
ĈLӋQWUӣ6KXQWӣYӏWUt
R
S1
= R
1
+ R
2
+ R
3
1ӝLWUӣFӫDFѫFҩXOj5
m
.KLNKyD.ӣYӏWUt

ĈLӋQWUӣ6KXQWӣYӏWUt
R
S2
= R
1
+ R
2
1ӝLWUӣFӫDFѫFҩXOj5
m
+ R
3
.KLNKyD.ӣYӏWUt
ĈLӋQWUӣ6KXQWӣYӏWUt
R
S2
= R
1
1ӝLWUӣFӫDFѫFҩXOj5
m
+ R
3
+ R
2
9tGͭ&KRFѫFҩXÿRFyQӝLWUӣ5
m
= 1k: 'zQJÿLӋQOӟQQKҩWTXDFѫFҩXOjPA. Tính
FiFÿLӋQWUӣ6KXQWӣWҫPÿRP$WҫPÿRP$WҫPÿRP$
*LҧL
ӢWҫPÿRP$
ÈSGөQJF{QJWKӭF

max.
max.
*
Atai
mA
S
II
RI
R


Ta có



max.
max.
3211
*
Atai
mA
S
II
RI
RRRR
:


6,52
10*950

1*10*50
6
3
ӢWҫPÿRP$
ÈSGөQJF{QJWKӭF
max.
max.
*
Atai
mA
S
II
RI
R


Ta có:




max.
3max.
212
*
Atai
mA
S
II
RRI

RRR
199
.1
10*9950
).1(*10*50
3
6
3
6
RkRk :

:


ӢWҫPÿRP$
ÈSGөQJF{QJWKӭF
max.
max.
.
Atai
mA
S
II
RI
R


Hình 3.3: MҥFKÿRNLӇu Shunt Ayrton
C
I

3
I
A
I
R
1
R
2
R
3
I
2
I
1
1
2
3
K
I
m

ĈRO˱ͥQJÿL͏Q
%͡P{Q&XQJ&̭SĈL͏Q Trang 23
Ta có:




max.
23max.

13
.
Atai
mA
S
II
RRRI
RR
1999
.1
10.99950
).1.(10.50
23
6
23
6
RRkRRk :

:


Thay vào ta có:
3
3
21
6,52
199
.1
R
Rk

RR :
:

:

 337,47
200
10004,10467
3
R
:

526,0
2000
6,1052
1999
6,521000
1
1
R
R
R
2
= 52,6 - (47,337 + 0,526) = 4,737:
9ұ\JLiWUӏFiFÿLrQWUӣ6KXQWӣFiFWҫPÿROj
R
S1
= R
1
+ R

2
+ R
3
= 0,526 + 4,737 + 47,337 = 52,6 :
R
S2
= R
1
+ R
2
= 0,526 +4,737 = 5,263 :
R
S3
= R
1
= 0,526 :
G0ӣUӝQJWҫPÿRFKRFѫFҩXÿLӋQWӯ
7KD\ ÿәL Vӕ YzQJ Gk\ TXҩQ FKR FXӝQ Gk\ Fӕ ÿӏQK YӟL OӵF ÿLӋQ Wӯ ) NK{QJ ÿәL
F = n
1
.I
1
= n
2
I
2
= n
3
I
3

=
9tGө) $PSHYzQJFKRWҫPÿR
I
1
= 1A; I
2
= 5A; I
3
= 10A.
.KLÿy n
1
= 300 vòQJFKRWҫPÿR$
n
2
YzQJFKRWҫPÿR$
n
3
YzQJFKRWҫPÿR$
H0ӣUӝQJWҫPÿRFKRFѫFҩXÿLӋQÿӝQJ
0ҳFVRQJVRQJFiFÿLӋQWUӣ6KXQWYӟLFXӝQGk\GLÿӝQJ&iFKWtQKÿLӋQWUӣ6KXQW
JLӕQJQKѭYӟLFiFKWtQKӣFѫFҩXWӯÿLӋQ
ĈRGzQJÿLӋQ[RD\FKLӅX$&
D1JX\rQOêÿR
&ѫFҩXÿLӋQWӯYjÿLӋQÿӝQJÿӅXKRҥWÿӝQJÿѭӧFYӟLGzQJÿLӋQ[RD\FKLӅXGRÿyFy
WKӇGQJKDLFѫFҩXQj\WUӵFWLӃSYjPӣUӝQJWҫPÿRQKѭ$PSHPpWÿRGzQJÿLӋQPӝW
FKLӅX
5LrQJFѫFҩXWӯÿLӋQNKLGQJSKҧLELӃQÿәLGzQJÿLӋQ[RD\FKLӅXWKjQKGzQJÿLӋQ
PӝWFKLӅX1JRjLUDGRWtQKFKtQK[iFFӫDFѫFҩXWӯÿLӋQQrQFѫFҩXQj\UҩWWK{QJGөQJ
WURQJSKҫQOӟQ$PSHPpWWURQJPi\ÿRYҥQQăQJ920
E0ӣUӝQJWҫPÿR

ĈRO˱ͥQJÿL͏Q
%͡P{Q&XQJ&̭SĈL͏Q Trang 24
- 'QJÿLӋQWUӣ6KXQWYjÿL{WFKRFѫFҩXWӯÿLӋQ$PSHPpWFKӍQKOѭX
ĈL{WPҳFQӕLWLӃSYӟLFѫFҩXGRÿyGzQJÿLӋQL
cLtb
TXDFѫFҩXGzQJFzQOҥLTXDÿLӋQ
WUӣ6KXQW
1yLFKXQJFiF$PSHPpWFKӍQKOѭXFyÿӝFKtQK[iFNK{QJFDRGRKӋVӕFKӍQKOѭX
WKD\ÿәLWKHRQKLӋWÿӝWKD\ÿәLWKHRWҫQVӕ9uYұ\FҫQSKҧLEQKLӋWÿӝYjEWҫQVӕ
'ѭӟLÿk\OjFiFVѫÿzEWҫQVӕFӫDFiF$PSHPpWFKӍQKOѭXEҵQJFXӝQFҧPYjWөÿLӋQ&
0һWNKiF FiF $PSHPpWWӯ ÿLӋQ FKӍQKOѭXÿѭӧF WtQK WRiQ YӟL GzQJÿLӋQFy GҥQJ
KuQKVLQKӋVӕKình dáng K
hd
= 1,1
I
Dk
BSW
hd
.
D
.KLÿRYӟLFiFGzQJÿLӋQNK{QJSKҧLKuQKVLQVӁJk\VDLVӕ
ѬXÿLӇPFӫDGөQJFөQj\OjÿӝQKҥ\FDRWLrXWKөF{QJVXҩWQKӓFyWKӇOjPYLӋFӣ
WҫQVӕ+]y 1kHz.
1KѭӧFÿLӇPÿӝFKtQK[iFWKҩS
- Ampemét ÿLӋQWӯOjGөQJFөÿRGzQJÿLӋQGӵDWUrQFѫFҩXFKӍWKӏÿLӋQWӯ0ӛLFѫ
FҩXÿLӋQWӯÿѭӧFFKӃWҥRYӟLVӕ$PSHYjVӕYzQJQKҩWÿӏQK
9tGө
&XӝQGk\WUzQFy,: $YzQJFXӝQGҽWFy
AIW 150100 y

YzQJGRÿyNKL
PӣUӝQJWKDQJÿRFKӍFҫQWKD\ÿәLVDRFKR,:OjKҵQJVӕEҵQJFiFKFKLDÿRҥQGk\WKjQK
QKLӅXÿRҥQEҵQJQKDXYjWKD\ÿәLFiFKQӕLJKpSFiFÿRҥQÿyQKѭKuQKDÿӇÿRGzQJ
ÿLӋQQKӓKuQKEÿӇÿRGzQJÿLӋQWUXQJEuQKKuQKFÿӇÿRGzQJÿLӋQOӟQ
Hình 3.4: Ampemét chӍQKOѭX
C
R
M
R
S
I
CLTB
V
D
I
S
+
-
I
AC
+uQK&iFSKѭѫQJSKiSEWҫn sӕ cӫa Ampemét chӍQKOѭX
a. Bù tҫn sӕ cӫa Ampemét chӍQKOѭXEҵng
cuӝn cҧm
C
R
CU
LR
MN
R
C

b. Bù tҫn sӕ cӫa Ampemét chӍnh
OѭXEҵng tөÿLӋn C
cҧm
C
C
R
CU
R
MN

ĈRO˱ͥQJÿL͏Q
%͡P{Q&XQJ&̭SĈL͏Q Trang 25
- $PSHPpWÿLӋQÿӝQJWKѭӡQJVӱGөQJÿRGzQJÿLӋQӣWҫQVӕ+]KRһFFDRKѫQ
(400 y YӟLÿӝFKtQK[iFFDRFҩSy 0,2).
7\WKHRGzQJÿLӋQFҫQÿRPjFXӝQGk\WƭQKYjFXӝQGk\ÿӝQJÿѭӧFPҳFQӕLWLӃS
KRһFVRQJVRQJKuQK
- .KLGzQJÿLӋQFҫQÿRQKӓKѫQ$QJѭӡLWDPҳFQӕLWLӃSFXӝQGk\WƭQK$
1,
A
2
) và
FXӝQGk\ÿӝQJKuQKD
- .KLGzQJÿLӋQFҫQÿROӟQKѫQ$FXӝQGk\WƭQKYjFXӝQGk\ÿӝQJÿѭӧFJKpS
song song (hình 3.7b).
$PSHPpWÿLӋQÿӝQJFyÿӝFKtQK[iFFDRQrQÿѭӧFVӱGөQJOjPGөQJFөPүX&iF
SKҫQWӱ5/WURQJVѫÿӗGQJÿӇEVDLVӕWҫQVӕYjWҥRFKRGzQJÿLӋQӣFXӝQGk\
trùng pha nhau.
.KLFҫQÿRFiFGzQJÿLӋQOӟQÿӇPӣUӝQJWKDQJÿRQJѭӡLWDFzQGQJPi\ELӃQ
GzQJÿLӋQ%,
&ҩX WҥRFӫDELӃQGzQJJӗPFyFXӝQGk\

b. ĈRGzQJÿLӋn trung bình
Hình 3.6: Mӣ rӝQJWKDQJÿRFӫD$PSHPpWÿLӋn tӯ
I
1
I
2
II
FĈRGzQJÿLӋn lӟn
I
I
DĈRGzQJÿLӋn nhӓ
+uQK6ѫÿӗ $PSHPpWÿLӋQÿӝng
b. A-mét
B
A
1
L
1
R
1
A
2
L
2
R
2
a. mA-mét
B
A
2

A
1

ĈRO˱ͥQJÿL͏Q
%͡P{Q&XQJ&̭SĈL͏Q Trang 26
- &XӝQVѫFҩS:
1,
ÿѭӧFPҳFQӕLWLӃSYӟLPҥFKÿLӋQFyGzQJ,
1
FҫQÿR
- &XӝQWKӭFҩS:
2
PҳFQӕLWLӃSYӟL$PSHPpWFyGzQJÿLӋQ,
2
FKҥ\TXD
ĈӇÿҧPEҧRDQWRjQFXӝQWKӭFҩSOX{QOX{QÿѭӧFQӕLÿҩW
&XӝQWKӭFҩSÿѭӧFFKӃWҥRYӟLGzQJÿLӋQÿӏQKPӭFOj$&KҷQJKҥQWDWKѭӡQJ
JһS Pi\ ELӃQ GzQJ Fy GzQJ ÿLӋQ ÿӏQK PӭF Oj $ $ $ $ 7Uӯ
QKӳQJWUѭӡQJKӧSÿһFELӋW
7DFyWӹVӕELӃQGzQJ
1
2
2
1
W
W
I
I
K
i

7ӹVӕ.
i
EDRJLӡFNJQJÿѭӧFWtQKVҹQNKLWKLӃWNӃ%,QrQNKLWUrQDPSHPpWFyVӕÿR
I
2
WDGӉGjQJWtQKQJD\ÿѭӧF,
1
I
1
= K
i
I
2
9tGө %LӃQGzQJÿLӋQFyGzQJÿLӋQÿӏQKPӭFOj$:
1
= 1 vòng.
;iFÿӏQKVӕYzQJFӫDFXӝQWKӭFҩSYjWuP[HPNKLDPSHPpWWKӭFҩSFKӍ,
2
= 2,85A
WKuGzQJÿLӋQFXӝQVѫFҩSOjEDRQKLrX
*LҧL
- 7ӹVӕELӃQGzQJ
120
5
600

i
K
- 6ӕYzQJFXӝQWKӭFҩS:

2
= K
i
W
1
= 120 vòng
- 'zQJÿLӋQVѫFҩS,
1
= K
i
I
2
=120 x 2,85 = 342A
Ampe kìm:
$PSHNuPOjPӝWPi\ELӃQGzQJFyOҳSVҹQPӝWDPSHPpWYjRFXӝQWKӭFҩSĈѭӡQJ
Gk\FyGzQJÿLӋQFҫQÿRÿyQJYDLWUzFXӝQVѫFҩS0ҥFKWӯFӫD$PSHNuPFyWKӇPӣUD
QKѭPӝWFKLӃFNuP.KLFҫQÿRGzQJÿLӋQFӫDPӝWÿѭӡQJGk\QjRÿyFKӍYLӋFPӣPҥFKWӯ
UDYjFKRÿѭӡQJGk\ÿyYjRJLӳDNuPUӗLÿyQJPҥFKWӯOҥL$PSHPpWJҳQWUrQNuPVӁFKӍ
FKRELӃWJLiWUӏGzQJÿLӋQFҫQÿR
&KӭFQăQJFKtQKFӫD$PSHNuPOjÿRGzQJÿLӋQ[RD\FKLӅXÿӃQYjLWUăPDPSHPj
NK{QJFҫQSKҧLFҳWPҥFKÿLӋQWKѭӡQJGQJÿӇÿRGzQJÿLӋQWUrQÿѭӡQJGk\GzQJÿLӋQ
TXDFiFPi\PyFÿDQJOjPYLӋF
I
1
A
W
1
W
2
I

2
Hình 36ѫÿӗ cҩu tҥo BI

ĈRO˱ͥQJÿL͏Q
%͡P{Q&XQJ&̭SĈL͏Q Trang 27
Ngoài UDWUrQ$PSHNuPFzQFyFiFWKDQJÿR$&9'&9YjWKDQJÿRÿLӋQWUӣ
ѬXÿLӇPJӑQQKҽVӱGөQJWKXұQWLӋQDQWRjQ7KѭӡQJGQJÿӇÿRGzQJÿLӋQWUrQ
ÿѭӡQJGk\GzQJÿLӋQFKҥ\TXDFiFPi\PyFÿDQJYұQKjQKPjNK{QJFҫQFҳWPҥFK
1KѭӧFÿLӇPFKӏXҧQKKѭӣQJFӫDWӯWUѭӡQJQJRjL
ĈRÿLӋQiS
'өQJFөÿRYjSKѭѫQJSKiSÿR
D'өQJFөÿRĈӇÿRÿLӋQiSÿӑFWKҷQJWUӏVӕWDGQJ9{QPpW
.êKLӋX
E3KѭѫQJSKiSÿR
Khi ÿR9{QPpWÿѭӧFPҳFVRQJVRQJYӟLÿRҥQPҥFKFҫQÿR

Ta có:
V
V
r
U
I
(1)
r
V
+ҵQJVӕELӃW,
V
VX\UDÿLӋQiS8
OFF
:

DCV
ACV
ACA
1
2
3
4
5
6
7
8
:
V
A
Hình 3.9: KӃt cҩu ngoài cӫa Ampe kìm
1.Gӑng kìm; 2. Chӕt mӣ gӑng kìm;
3. Núm xoay; 4. Nút khóa kim;
V
+uQK6ѫÿӗ mҳc vôn mét
V
r
V
I
I
Phө tҧi

ĈRO˱ͥQJÿL͏Q
%͡P{Q&XQJ&̭SĈL͏Q Trang 28
'zQJTXDFѫFҩX,
V

làm TXD\NLPPӝWJyFWӹOӋYӟLGzQJÿLӋQ,
V
FNJQJFKtQKWӹOӋ
YӟLÿLӋQiSFҫQÿR87UrQWKDQJÿRWDJKLWKҷQJWUӏVӕÿLӋQiS
7ӯVX\UD,
V
Jk\VDLVӕPXӕQJLҧPVDLVӕWKuSKҧLWăQJÿLӋQWUӣU
V
.
0һWNKiF9{QPpWFNJQJWLrXWKөPӝWOѭӧQJF{QVXҩW
V
V
r
U
P
2

 r
V
FjQJOӟQWKu
P
V
FjQJQKӓÿLӋQiS8ÿRÿѭӧFFjQJFKtQK[iF
ĈRÿLӋQiS'&
D1JX\rQOêÿR
ĈLӋQiSÿѭӧFFKX\ӇQWKjQKGzQJÿLӋQÿRÿLTXDFѫFҩXÿR
1ӃXFѫFҩXÿRFy,
max
YjÿLӋQWUӣQӕLWLӃS5WKu

MAX
m
do
do
I
RR
V
I d


9ӟL5
m
OjÿLӋQWUӣWURQJFӫDFѫFҩXÿR
7әQJWUӣYjR9{QNӃ=
V
= R + R
m
&iFFѫFҩXWӯÿLӋQÿLӋQWӯÿLӋQÿӝQJÿӅXÿѭӧFGQJOjP9{QPpW'&%ҵQJFiFK
QӕLWLӃSÿLӋQWUӣÿӇKҥQFKӃGzQJÿLӋQTXDFѫFҩXFKӍWKӏ5LrQJFѫFҩXÿLӋQÿӝQJFXӝQ
Gk\GLÿӝQJYjFXӝQGk\FӕÿӏQKPҳFQӕLWLӃS
E0ӣUӝQJJLӟLKҥQÿR
0ӛLFѫFҩXÿRFKӍJLӟLKҥQÿRÿѭӧFPӝWJLiWUӏQKҩWÿӏQK9uYұ\ÿӇPӣUӝQJJLӟL
KҥQÿRFӫD9{QPpW .KLÿLӋQ iS FҫQÿR YѭӧW TXiJLӟL KҥQÿR FKR SKpSFӫD 9{QPpW
QJѭӡLWDPҳFWKrPPӝWÿLӋQWUӣSKө5
P
QӕLWLӃSYӟLFѫFҩXÿR
Ta có: U
P
= IR
P


P
P
R
U
I

U
V
= I.r
V

V
V
r
U
I

V
V
P
P
r
U
R
U


V
P

V
P
r
R
U
U


V
VP
V
VP
r
rR
U
UU 


Vì: U
P
+ U
V
= U
nên:
V
P
V
VP
V
r

R
r
rR
U
U


1
ĈһW
U
V
P
n
r
R
1
U
V
n
U
U

 U = U
V
.n
u
V
P
U
r

R
n  1(
EӝLVӕÿLӋQWUӣSKө
+ӋVӕQ
u
FKRELӃWNKLPҳFÿLӋQWUӣSKөWKuWKDQJÿRFӫD9{QPpWÿѭӧFPӣUӝQJQ
u
OҫQ
1ӃX5
p
UҩWOӟQVRYӟLU
V
WKuWKDQJÿRFjQJÿѭӧFPӣUӝQJ
R
P
FjQJOӟQVRYӟLU
v
WKuFӣÿRFjQJÿѭӧFPӣUӝQJ
+uQKGQJÿLӋn trӣ phө (R
P
ÿӇ mӣ rӝng giӟi
hҥQÿRFKR9{QPpW
V
r
V
I
Phө tҧi
R
P
U

p
U
V
U