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2
2.1 (dc machine),
. , . , 19 , .
1832 Hippolyte Pixii. Pixii . , , Werner Von Siemens 1856, . HefnerAlteneck 1872.
, . , .
2.2 .
(stator) (rotor). . 2.1 . . , , B. , .
. 2
22
S
+_
i
=0
B
F
F
eR
r
++
_
_
e
e
l
. 2.1
,
. , . , . , (brushes). .
, . , , . , (. 2.2). , . , , .
2.2.1
(. 2.1),
. 2
23
. , . , . . 1.18,
( )e = v B l (2.1) ,
, . , l,
e e vBl = = (2.2)
, .
S
N
. 2.2 ,
.
. 2
24
0 90o 180o 270o 360o
ee rC
e rC
e
0 90o 180o 270o 360o
() () . 2.3
() ()
, , 2e vBl= (2.3) , . ,
. 180, . 2.1, . , . , , . 2.3. , (. 2.3).
. (2.3) . . (2.3), v ,
rv r= (2.4)
, r () r rad/s. Sp, , r l. ,
12 (2 )pS rl rl = = (2.5)
,
pS B = (2.6)
. (2.4), (2.5) (2.6) . (2.3),
2e r re C = = (2.7)
. (2.7) , . ,
. 2
25
. Ce 2/. .
. 2.1 , . R, i. Lenz . 2.1. , Laplace. Laplace, Lenz , . , ( ), .
2.2.2
. 2.1,
. 2.3. . , . 2.1 .
S
=0
B
F
F
R
r
++
_
_
e
e
+ _
ie
bp bn
R
+bp
_bn
i
=180
+
+
_
_
. 2.4
. 2
26
0 90o 180o 270o 360o
ee rC
. 2.5 ,
,
(. 2.4). . . , bp . , bn . , (. 2.5). , .
180 , . (commutation). , . ( ). , .
2.2.3
(),
, . Laplace , . Laplace . 1.19,
( )i= F l B (2.8)
Laplace . 2.6, F F F ilB = = = (2.9)
0F F = = (2.10)
Laplace
sinT T rF rilB = = = (2.11)
r F, 90. , ,
. 2
27
22 TT T T rilB C i i = + = = = (2.12)
.
, . 2.5. , . , , (. 2.4).
. (2.12) . CT, , i . . 2.6 , CT = 2/.
, , ( ). , ea.
S
=0
B
F
F
V
r
++
_
_
e
e
+ _
iea
bp bn
. 2.6
. 2
28
2.3 ,
, (armature), . , . , , , . , . , , (coils). (turns). . , , ().
180 . e m,
2e mP = (2.13)
, . 90 . , 180 . , 180 , , . , . (full pitch coils). 180, (fractional pitch coils).
(simplex) (multiplex). , . . 1, 3, 5 2, 4, 6 , , .
, (two layer winding). , .
, , (lap windings), (wave windings) (frog leg).
2.3.1
,
. . , . , , . ,
. 2
29
. . . 2.7 16 .
. . , .
, .
2.3.2
,
(. 2.8). , . , , , , . , , .
2.3.3
. 2m, m .
. 2.7 16
. 2.8
. 2
210
2.4 , ,
, . , . 2.3. , (yoke), . , , . . 2.9. . 2.10.
, .
, , . . . . . , (air gap), . . , .
. , . , . , . .
. , . , . , , , .
, . , . . . . , , , . , , .
, , . , , . , . , .
. 2
211
. , , , . (National Electrical Manufacturers Association), 70C, 100C, F 130C 155C.
N S
S N
S S
N
N
. 2.9
. 2
212
-
-
. 2.10 . LeroySomer
2.5
,
. . , (main field). , ,
. 2
213
. (armature field), . , , (armature reaction).
. (flux weakening). 2.5.1
,
. . . 2.4 .
, . , . 2.11, . , , . (. 2.11) (. 2.11). , . , , .
, , . , , . , .
2.5.2
, . . 2.11 , . . , , . .
, . , . , . . , .
. 2
214
S
Ne
Bt
BaG
NS
()
Ba
BeBt
S
N e
Bt
Ba
M
() () . 2.11 (). ()
() 2.5.3
, .
, , . . ,
. 2
215
. , .
, , . . 2.12 , . , , . , , .
S
N
N
d-
S
SN
S N
G
. 2.12
. 2
216
1hp. , , . , . 2.5.4
,
. , . (compensating winding) . , . , . , , . , , . .
. , Ldi/dt. , , . .
2.6 , ,
, () , . , Pout Pin, Ploss
out in lossP P P= (2.14) ,
(efficiency)
100%outin
PP
= (2.15)
: (copper losses). Pcu
a e, Ra Re
2 2cu a a e eP I R I R= + (2.16)
. 2
217
(iron, core losses). Piron
. r
2 1.5iron i rP C (2.17) (mechanical losses). Pfw,
(friction) (windage). . .
br br aP V I= (2.18)
, Ia Vbr . 2V, . (stray losses). ,
. Pstray . , 1% , .
2 2stray s a rP C I (2.19) ,
, loss cu iron fw br strayP P P P P P= + + + + (2.20) , Ce = CT 2/,
,
2e T
z PC Cb= = (2.21)
, , z b . , P = 2, z = 2 b = 1.