lekts 8
TRANSCRIPT
, ..- 1891 . , , , , . . , 120- I . . 120- . . , . , , . 120- . . . 120- .eA = EmA sin t eC = EmC eB = EmB t 1200
( ) (t 240 )0
1- - , . - :E A = E;
EB = Ee j120 ;0
EC = Ee j 240
0
1 - (), ()
- .U A = EA; U B = EB ; U C = EC
- , - , - _^ ^?? - , 120- . , . 2 - , - , ,
2 (), () . , , , ,,Z
, . () - .
.E A + EB + EC = E + Ee j120 + Ee 240 = 00 0
. , . , , . (Z= ZB =ZC ) ( ZA ZB ZC ) . (,, ), (,,) . , U , I
-
. (), (1) . , , U 00 , I 00 - . .
I = I U= 3 .
.U AB + U AC + U CB = 0
3 .
.
U = U 3 .
I = 3I . : 1. 2. 3. - - - .
4. 5.
- -
, (,,Z) , ' . , ' . , . . ( 3)
3 - : -; -; - - ; -' - ; I,- ; I A ; I B ; I C - ; U A ; U B ; U C - ; I AB ; I CA ; I BC - ;
Z A ; Z B ; Z C ; - . - . , . , . , . .
U AB = U A U B U BC = U B U C U AC = U A U C
4 . . 0,0' m . . ( 4) 0 , .
U AB ( 8)
U A - U B . U BC ,
U CA .
, . .U AB + U CB + U AC = 0
. , . U AB :
AB = U AB = 2U B cos 300 U AB = U ;U
U = U
2 3U 3U ; U = 3U 2
I=I .I A + I B + IC = 0
3 , .
: U U U I A = A = I Ae j A ; I B = B = I B e j A ; I C = C = I C e j C ZA ZB ZC
:IA = IB = IC = UA ; ZA UB ; ZB UC ; ZC
A = arctg B = arctg
XA RA
XB RB XC RC
C = arctg
I A ; I B ; I C , A ; B ; C - .
,
5.
, ( Z A Z B Z C ) ( I A I B I C ) . I 001 .
. I .I 001 = I A + I B + I C
, .
6. _ - ,
.I 001 = I A + I B + I C = 0
. . ( 7). - , - (, , , .) . .
I A + I B + IC = 0 . : I A =
AA Za
;
IB =
AB Zb
;
IC =
AC Zc
;
7. - . (3 8)
8 - - . (1) U 001
E Y + EB Yb + EC Yc = A a Ya + Yb + Yc + Y001
: Ya =
1 1 1 - ; Yb = ; Yc = Za Zb Zc 1 Z 001
Y001 =
Ya = Yb = Yc ; .U 001
(
Y001 = 0
)
E Y + EB Yb + EC Yv = A a =0 YA + YB + YC
.U AO1 = E A ; U BO1 = EB ; U CO1 = EC ;
U 0O1 0U AO1 = E A U 0O1 U BO1 = EB U 0O1 . U CO1 = EC U 0O1
: I A =
U AO1 Za
; IB =
U BO1 Zb
; IC =
U CO1 Zc
:
I 001 =
U 0O1 Z 00
.
9- .
9 .
. , . (0) (0) ( U 001 ) .