() (. 17.1), . :
: I N = I A + I B + I C.
. 17.1
UA, UB, UC RA = RB = RC = R IA, IB, IC (IN) .
I = I = U R; IN = 0.
, IN ¹ 0. (. 17.2).
. 17.2.
: SP = P + P + P.
,
SP = 3 P = 3U × I.
(- -) :
SP = 3 ×U ×I × cosj = Ö3 × U × I × cosj.
SQ = 3 ×U ×I × sinj = Ö3 ×U × I × sinj.
SS = 3 ×U I = Ö3 ×U × I .
.
17.2.1..
I IN, U U, P SP, .
(RA = RB = RC = 1 ) (. 17.3).
. 17..3
. 17.1 .
17.1
, | IA | ||
IB | |||
IC | |||
IN | |||
. , | UAB | ||
UBC | |||
UCA | |||
, | UA | ||
UB | |||
UC | |||
, | PA | ||
PB | |||
PC | |||
, | SP |
(RA = 1 , RB = 680 , RC = 330 ).
. 17.4 .
. 17.4.
.
1.
2.
3.
4.
|
|
5.
6.
7.
8.
17.4. 17.
1. 17, . .
2. 17.3.
3. RA = RB = RC = 1 , 17.3.
4.
. 17.1 .
5. (RA = 1 , RB = 680 , RC = 330 ), .17.1
5. 4.
6. , .
7. .
8. , , , .
18.
,
: ;
.