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() , ():
. 1 . , . , .
- u(t) = Um sin (ωt + φ)
- i(t) = Im sin (ωt + φ),
Um, Im - ( - pk)
(ωt + φ) -
φ -
ω - , ω = 2πf, (/), f - ()
=1/f - ().
/ /, .
I=√(1/T∫Im2sin2(ωt + φ)dt)= Im/√2; U=√(1/T∫Um2sin2(ωt + φ)dt)= Um/√2;
( ) ( e(jφ) = cosφ + jsinφ; j=√(-1):
Ū = U e(jφ) = U (cosφ + jsinφ) = (U1 + jU2), U = √ ((U1)2 + (U2)2),
Ī = I e(jφ) = I (cosφ + jsinφ) = (I1 + jI2), U = √ ((I1)2 + (I2)2).
: R, g = 1/R. Im=Um/R, I=U/R, i(t)=u(t)/R;
: R(ω), G(ω) - const ( ).
R G .
L ( ).
. UL=L(di/dt).
: xL = ωL; bL = 1/xL = 1/ωL.
: XL = jxL = xL e(j90), BL = jbL = j(1/ωL) = bLe(j90).
C ().
. UC=1/C∫i(t)dt;
: xC = 1/ωC; bC = 1/xC = ωC.
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: XC = jxC = xC e(j90), BC = jbC = jωC = bCe(j90).
R, L, C : z = √(R2 + (xL xC)2)= √ (R2 + x2).
Im XL
Z X Z
φ X R Re
R Re XC
. 2. . 3. (X=XL-XC)
R, L, C : y = √ (g2 + (bC bL)2).
:
Z = z e(jφ) = R + jx; φ = arctg (x/R) - () Y = y e(jΨ) = g + jb, Ψ = arctg (b/g) = (900 φ).
:
Ŝ = Ū×Ï = P jQ = S e(jφ). φ = arctg (Q/P) = arctg (x/R) - () ( R, Z).
.
() S = U×I = √ (P2 + Q2), (*).
() P = S cos φ, P = I2R, () , .
(-) Q = S sin φ, Q = I2x, (*A) - , L C .
5
1:
( ) (, , ). Multisim, , , (VRMS,Vpeak,,(), f(), Ψe()).
:
VRMS=42.3 ;
f=100 ;
Ψe=120;
, :
Em, | f, f=1/ | , =1/f | ω, / ω=2 f | - Ψe, | , | ||
(RMS - root-mean-square) VRMS= | , Vpeak= VRMS | , (peak to peak) Vp-p, Vp-p=2Vp | |||||
42.3 | 59.643 | 119.286 | 100 | 120 | u=59.643sin(628t+120) |
Vpeak= VRMS=42.3 59.643 ;
Vp-p=2Vpeak=119.286 ;
T=1/f=1/100=0.01 c= 10 ;
ω=2 f=2 100=200
u=Umsin(ωt+ Ψe)= 59.643sin(628t+120)
,
Ū = Um e(jφ) = U (cosφ + jsinφ)= 59.643ej(628 t+120) = 59.643 (cos(628 t+120) + jsin(628 t+120))
. 1.1. Multisim.
. 1.2. .
2:
( ) , , , , , . Multisim, , (VRMS , Vpeak, ,(), f (), Ψe ()). (i(t)), (J) .
:
u(t)=310sin(314t-120);
, , u=Umsin(ωt+ Ψe), :
Em, | f, f=1/ | , =1/f | ω, / ω=2 f | - Ψe, | , | ||
(RMS - root-mean-square) VRMS= | , Vpeak= VRMS | , (peak to peak) Vp-p, Vp-p=2Vp | |||||
219.9 | 314 100 | -120 | u=31sin(314t-120) |
VRMS= Vpeak/20.5 ;
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Vpeak= 310 ;
Vp-p=2Vpeak=620 ;
ω=314
T=2π/ ω =2π/100π=0.05 c= 50 ;
f=1/T=1/0.05=20 U=;
Ψe=-120;
, Ū = Um e(jφ) = U (cosφ + jsinφ)=310ej(314t-120) = 310 (cos(100πt-120) + jsin(100πt-120)) B;
Ī =Ū/R=0.310ej(100πt-120) = 0.310 (cos(100πt-120) + jsin(100πt-120)) A=310 (cos(100πt-120) + jsin(100πt-120)) ;
i, 100 A/ |
-100 |
-200 |
t, 5 / |
. 2.1. i(t)
Im, j*mA
i0
ω Im =310 Re, mA
Ψe= -120
Ī0
. 2.2. Ī0 .
Ī 0= 0.310ej(-120) = 0.310 (cos(-120) + jsin(-120)) A=-0.310 (cos(60) + jsin(60)) A =-0.155(1+ j) A=-155(1+ j) mA;
. 2.3. Multisim.
. 2.4. .
3:
R . ( 2) R . , , , , , . Multisim, (VRMS, Vpeak, ,(), f(), Ψe (), i(t), u(t), p(t)).
:
u(t)=310sin(314t-120);
R1 = 5 ;
R2 = R = 10 = 0,01 ;
, :
Em, | f, f=1/ | , =1/f | ω, / ω=2 f | - Ψe, | , | ||
(RMS - root-mean-square) VRMS= | , Vpeak= VRMS | , (peak to peak) Vp-p, Vp-p=2Vp | |||||
219.858 | 620 | 50 | 100 | -120 | u=310sin(100 t+45) |
Vpeak=310 ;
VRMS=Vpeak/20.5=219.858 ;
T=1/f=1/50=0.02 c= 20 ;
ω=2 f=2 50=100
u=Umsin(ωt+ Ψe)= 310sin(100 t-120);
, Ū = Um e(jφ) = U (cosφ + jsinφ)=310ej(100πt-120) = 310(cos(100πt-120) + jsin(100πt-120))
Ū 0= 310ej(-120) = 310 (cos(60) + jsin(60)) B
Im, j*
Ū0
ω Ψe=60
Um =310 Re,
. 3.1. Ū0 .
. 3.2. Multisim.
. 3.3. .
4.
L . ( 2) L . , , , , , . Multisim, (VRMS , Vpeak, ,(), f (), Ψe (), i(t), u(t), p(t)).
VRMS = 219.858
Vpeak, =310
f = 50 ,
Ψe =-120
,() = 20
. 4.1. Multisim.
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. 4.2. .
, , UL IL . PL(t) T . T UL IL , , .. , . UL IL , . , . L, .
5.
C . ( 2) C . , , , , , . Multisim, (VRMS , Vpeak, ,(), f (), Ψe (), i(t), u(t), p(t)).
VRMS = 219,858
Vpeak, =310
f = 50 ,
Ψe =-120
= 0,02
= 5
. 5.1. Multisim.
. 5.2. .
, , PL
Pc(t) .
T Uc Ic , , . . , .
3 : VRMS, Vpeak, Vp-p;
VRMS , U. . . u(t) i(t) .
Em . . .