- . ,
.
, Rx , . 2.1, . DR, .
) )
. 5.1.
-
, . 5.1,
,
.5.1, ,
. , , . 2.1, ,
, ,
. 5.1, .
Zx -
f (. 5.2). :
Zx =UV / I A,
UV, IA .
, ,
, . 5.2, ,
Zx << ZV, . 5.2, Zx >> ZV.
-
, . 2.3.
XC =1/wCx =UC / I,
Cx = I /wUC,
w = 2pf, f ; UC ,
.
, f. -
, . 2.3, ; -
. 2.3, .
. 2.2.
43
- ( ),
. 2.4.
U1 V1.
V2 0, :
U2 = I / wC0.
I
I =U1 /(1/ wCx +1/ wC0),
Cx = C0U2 /(U1 -U2).
0 >> , x:
Cx = C0U2 /U1.
.
) )
. 2.3. -
. 2.4.
44
-
, RL
XL (. 2.5, , ).
I =UL /wL,
L =UL / wI.
,
|
|
.
- 0,5... 10%
, -
. -
.
. -
. -
(. 2.6, )
(. 2.6, ) .
) )
. 2.5.
45
) )
. 2.6.
. , ,
R R R
U
I
x + A +
=,
RA ; Rp .
RA, Rp U -
a Rx, .. -
.
, (. 2.6).
, .. ,
Rx = ¥ Rx = 0
. ( Rx= ¥)
. ,
Rx = ¥. ,
, .. Rx = 0,
,
, Rp
. ,
, Rx. , ( -
46
), Rx
.
,
-
,
I =U /[R + RARx /(RA + Rx)]. (2.1)
,
R , (5..1) .
, Rx = 0
R = ¥ I Rp.
, -
Rx = ¥. . 2.6, .
, . 2.5, , ,
|
|
,
(, ). 2,5.
2.2.3.
:
.
. 2.7, .
,
R Rx ,
U. .
U Rx.
, -
. K -
R >> R,
Rx = (KU /U -1)R.
, Rx > R.
47
) )
. 2.7.
(Rx < R)
, . 2.7, .
Rx = R /(KU /U -1).
,
104... 102 1,5... 2,0%.
( 1018 ) .
(. 2.8).
, . 2.8, , Rx
Rx = RU /U,
U - ; R -
.
) )
. 2.8.
U R U -
Rx , ,
.
, .
Rx R, (. 2.8, ), ( ).
Rx = RU /U.
10%.
2.2.4.
, -
,
. (,
, )
, . , , .
, - ,
.
. (. 2.9) , .
R1, R2, R3 R4 ,
-
. , , . ab
|
|
. cd, , -
.
. .
. 2.9.
49
I , R U
()
[ ()() () ()].
1 2 3 4 1 2 3 4 3 4 1 2
1 3 2 4
R R R R R R R R R R R R R
U R R R R
I
+ + + + + +
= - (2.2)
: .
,
d , , , -
.
(2.2) , I = 0
R1R3 - R2R4 = 0. (2.3)
(2.3)
: ,
,
.
(, R4) , R1, R2 R3,
2
1
4 3 R
R
R = R.
R1/R2 R3, ,
, .
, ,
(
,
). -
, , , .
-
, ,
.
1 .
106... 108 .
-
.
50
, . (, ..). ,
R = R DR, ,
Rx = R, DR
a (
).
,
, .
, ,
|
|
,
.
2.2.5.
, ,
-
, .
.
, , , .
-
. 2.10.
, .
Z&i = Ri + jXi.
(2.3)
:
Z&1Z&3 = Z&2Z&4.
:
1 2 3 4,
1 2 3 4
Z e jj Z e jj = Z e jj Z e jj (2.4)
51
Zi, ; j .
(2.4) -
:
j + j = j + j
=
.
;
1 3 2 4
Z1Z3 Z2Z4
(2.5)
,
. ,
, ,
.
(2.5) ,
, .
, , (j = 0),
,
.
, . 2.10, .
R1 / wC = R2 /wCx,
,
Cx = (R2 / R1).
. 2.9, . . , (RL = 0),
wLx / wC = R2R4,
Lx = R2R4C.
, , . -
, , -
52
) )
. 2.10.
, ,
. , ,
, .
0,1 5,0.
100 1000 .
.
2.2.6.
, ( ).
, ,
. ,
. ,
. (. . 2.11) -
(), ,
|
|
L RL .
V1 V2.
.
53
. 2.11.
,
Q ,
U1. Q
Q = 1/ wCRL (2.6)
Q = wL / RL. (2.7)
: , Lx , L f .
V2 . (2.6) (2.7),
1/ ,
L 2C x = w
.
L
Lo6p .
L -
.
f = 1/(2p LC1). (2.8)
, ,
, ,
. ( -
) ,
1/ 2 (). f = p L C2 + x (2.9)
(2.8) (2.9),
Cx = C1 - 2.
U1 , , V2 . .
, () . - , .
, - , . , +-10% 25, 50, 60, 100, 150, 200, 300, 400, 430, 500, 800, 1000, 1500 2400 , 36, 110, 115, 127, 220 380 .
( 5 ) , , , , ; 1 . , , . , - . ( 50 ) , . ( 100 ) .
, , , , . , - .
10-11; , 10 0,0001 . , , - . , , 10-6, . , (100 200 , 2,5; 5; 10 15 ), , .
5-10%, - 0,1-1%, .