, , (. 14.7, ). a, b , , (14.18). 14.2, ,
I = I m cos ( w t - j), (14.34)
j .
` . 14.7
:
U = U m cos w t =UR + UL + UC. (14.35)
14.2, UR, UL UC c :
UR = U m cos (w t - j) (14.36)
( );
UI = UL m cos (w t - j + p/2) (14.37)
( p/2);
UC = UC m cos (w t - j - p/2) (14.38)
( p/2).
(14.36) (14.38) (14.35), . .
. 14.7, I m. , : UR m ; UL m - p/2, UC m c p/2. , U m j. ,
(14.39)
(14.39) (14.21), (14.27) (14.32) ,
(14.40)
Z , . (14.40)
(14.41)
R , . (XL ) . .
(. 14.7):
(14.42)
. 14.8 . 14.8 j :
(14.43)
(L = C), [. (14.41)] Z = R, (14.43) tg j = 0 j = 0. , , ; , .
.
UL m = UC m, L w = 1/( w). :
(14.44)
Z , R, . . 14.8.
|
|
L w > 1/( w), tg j > 0 j > 0, (. . 14.7, ). L w < 1/( w) tg j < 0 j < 0. . . 14.9.
. 14.9