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Ƚɥɚɜɚ 5. ȺȼɌɈȽȿɇȿɊȺɌɈɊɕ
5.1. Ɉɛɳɢɟ ɫɜɟɞɟɧɢɹ. ɍɪɚɜɧɟɧɢɟ ɚɜɬɨɝɟɧɟɪɚɬɨɪɚ
Ⱥɜɬɨɝɟɧɟɪɚɬɨɪɚɦɢ (ȺȽ) ɹɜɥɹɸɬɫɹ ɭɫɬɪɨɣɫɬɜɚ, ɜ ɤɨɬɨɪɵɯ ɷɧɟɪɝɢɹ ɢɫɬɨɱɧɢɤɚ
ɩɢɬɚɧɢɹ ɩɪɟɨɛɪɚɡɭɟɬɫɹ ɜ ɷɧɟɪɝɢɸ ɜɵɫɨɤɨɱɚɫɬɨɬɧɵɯ ɤɨɥɟɛɚɧɢɣ ɛɟɡ ɜɧɟɲɧɟɝɨ
ɜɨɡɛɭɠɞɟɧɢɹ.
ȺȽ ɹɜɥɹɸɬɫɹ ɩɟɪɜɢɱɧɵɦɢ ɢɫɬɨɱɧɢɤɚɦɢ ɤɨɥɟɛɚɧɢɣ, ɱɚɫɬɨɬɚ ɢ ɚɦɩɥɢɬɭɞɚ
ɤɨɬɨɪɵɯ ɨɩɪɟɞɟɥɹɸɬɫɹ ɬɨɥɶɤɨ ɫɨɛɫɬɜɟɧɧɵɦɢ ɩɚɪɚɦɟɬɪɚɦɢ ɫɯɟɦɵ ɢ ɞɨɥɠɧɵ ɜ
ɨɱɟɧɶ ɦɚɥɨɣ ɫɬɟɩɟɧɢ ɡɚɜɢɫɟɬɶ ɨɬ ɜɧɟɲɧɢɯ ɭɫɥɨɜɢɣ.
ȼ ɥɸɛɨɦ ȺȽ ɦɨɠɧɨ ɜɵɞɟɥɢɬɶ ɤɨɥɟɛɚɬɟɥɶɧɭɸ ɫɢɫɬɟɦɭ (Ʉɋ), ɤɨɥɟɛɚɧɢɹ ɜ
ɤɨɬɨɪɨɣ ɩɨɞɞɟɪɠɢɜɚɸɬɫɹ ɡɚ ɫɱɟɬ ɩɨɫɬɭɩɥɟɧɢɹ ɩɨɪɰɢɣ ɷɧɟɪɝɢɢ ɨɬ ɢɫɬɨɱɧɢɤɚ
ɩɢɬɚɧɢɹ. ɍɩɪɚɜɥɹɟɬ ɷɬɢɦ ɩɪɨɰɟɫɫɨɦ ɚɤɬɢɜɧɵɣ ɷɥɟɦɟɧɬ (Ⱥɗ) ɜ ɜɢɞɟ ɞɜɭɯ-
ɩɨɥɸɫɧɢɤɚ (ɬɭɧɧɟɥɶɧɵɣ ɞɢɨɞ, ɞɢɨɞ Ƚɚɧɧɚ ɢ ɞɪ.) ɢɥɢ ɬɪɟɯɩɨɥɸɫɧɢɤɚ
(ɬɪɚɧɡɢɫɬɨɪ, ɥɚɦɩɚ), ɢ ɧɚ ɤɨɬɨɪɵɣ ɜɨɡɞɟɣɫɬɜɭɸɬ ɤɨɥɟɛɚɧɢɹ, ɩɨɫɬɭɩɚɸɳɢɟ ɢɡ
Ʉɋ.
ɉɪɟɞɦɟɬɨɦ ɪɚɫɫɦɨɬɪɟɧɢɹ ɞɚɧɧɨɣ ɝɥɚɜɵ ɛɭɞɭɬ ɬɪɚɧɡɢɫɬɨɪɧɵɟ ȺȽ, ɨɛɨɛ-
ɳɟɧɧɭɸ ɫɯɟɦɭ ɤɨɬɨɪɵɯ ɦɨɠɧɨ ɩɪɟɞɫɬɚɜɢɬɶ ɜ ɜɢɞɟ, ɩɨɤɚɡɚɧɧɨɦ ɧɚ ɪɢɫ.5.1. ɇɚ
ɫɯɟɦɟ ɨɛɨɡɧɚɱɟɧɢɹ ɬɨɤɨɜ ɢ ɧɚɩɪɹɠɟ-
ɧɢɣ ɫɨɨɬɜɟɬɫɬɜɭɸɬ ɨɛɳɟɦɭ ɫɥɭɱɚɸ.
Ɇɵ ɩɪɢ ɚɧɚɥɢɡɟ ȺȽ ɚɤɬɢɜɧɵɣ ɱɟɬɵ-
ɪɟɯɩɨɥɸɫɧɢɤ ɛɭɞɟɦ ɫɱɢɬɚɬɶ ɢɞɟɚɥɶ-
ɧɵɦ, ɬ.ɟ. ɬɚɤɢɦ, ɭ ɤɨɬɨɪɨɝɨ ɜɯɨɞɧɨɟ
ɫɨɩɪɨɬɢɜɥɟɧɢɟ ɛɟɫɤɨɧɟɱɧɨ ɜɟɥɢɤɨ
(
I
ɜɯ
= 0), ɢ ɨɬɫɭɬɫɬɜɭɟɬ ɜɥɢɹɧɢɟ ɜɵ-
ɯɨɞɧɨɝɨ ɧɚɩɪɹɠɟɧɢɹ
U
ɜɵɯ
ɧɚ ɜɵɯɨɞ-
ɧɨɣ ɬɨɤ
I
ɜɵɯ
. Ⱦɥɹ ɛɨɥɶɲɢɧɫɬɜɚ ɩɪɚɤ-
ɬɢɱɟɫɤɢɯ ɫɥɭɱɚɟɜ ɬɚɤɨɟ ɩɪɟɞɩɨ-
ɥɨɠɟɧɢɟ ɦɨɠɧɨ ɞɨɩɭɫɬɢɬɶ ɢɥɢ
ɩɪɟɨɛɪɚɡɨɜɚɬɶ ɪɟɚɥɶɧɵɣ ɱɟɬɵɪɟɯɩɨ-
ɥɸɫɧɢɤ ɤ ɢɞɟɚɥɶɧɨɦɭ. ȼɵɯɨɞɧɨɣ ɬɨɤ
I
ɜɵɯ
ɢɞɟɚɥɶɧɨɝɨ ɱɟɬɵɪɟɯɩɨɥɸɫɧɢɤɚ
ɡɚɜɢɫɢɬ ɨɬ ɩɪɢɥɨɠɟɧɧɨɝɨ ɧɚ ɜɯɨɞ ɧɚɩɪɹɠɟɧɢɹ:
I
ɜɵɯ
= U
ɜɯ
S
1
; S
1
= S
1
exp(j
ϕ
s
),
ɝɞɟ
S
1
=
S
1
(
U
ɜɯ
) — ɭɫɪɟɞɧɟɧɧɚɹ ɩɨ ɩɟɪɜɨɣ ɝɚɪɦɨɧɢɤɟ ɤɪɭɬɢɡɧɚ ɩɪɨɯɨɞɧɨɣ
ɯɚɪɚɤɬɟɪɢɫɬɢɤɢ, ɤɨɬɨɪɚɹ ɡɚɜɢɫɢɬ ɨɬ ɚɦɩɥɢɬɭɞɵ ɜɯɨɞɧɨɝɨ ɧɚɩɪɹɠɟɧɢɹ;
ϕ
s
— ɮɚɡɨɜɚɹ ɡɚɞɟɪɠɤɚ ɜɵɯɨɞɧɨɝɨ ɬɨɤɚ
I
ɜɵɯ
ɨɬ ɭɩɪɚɜɥɹɸɳɟɝɨ ɜɯɨɞɧɨɝɨ
ɧɚɩɪɹɠɟɧɢɹ
U
ɜɯ
.
ȼɜɟɞɟɦ ɤɨɷɮɮɢɰɢɟɧɬ ɨɛɪɚɬɧɨɣ ɫɜɹɡɢ
k
ɨɫ
ɢ ɫɨɩɪɨɬɢɜɥɟɧɢɟ ɧɚɝɪɭɡɤɢ
Z
ɧ
:
k
U
U
Z
U
I
ɨɫ
ɜɯ
ɜɵɯ
k ɧ
ɜɵɯ
ɜɵɯ
ɧ ɧ
k j Z j= − = ⋅ = = ⋅exp( ); exp( ).
ϕ ϕ
ȼ ɷɬɨɦ ɫɥɭɱɚɟ ɭɪɚɜɧɟɧɢɟ ɚɜɬɨɝɟɧɟɪɚɬɨɪɚ ɢɦɟɟɬ ɜɢɞ
S
1
k
ɨɫ
Z
ɧ
= 1
. (5.2)
I
ɜɯ
I
ɜɵɯ
Ⱥɤɬɢɜɧɵɣ
U
ɜɯ
ɱɟɬɵɪɟɯ-
U
ɜɵɯ
ɩɨɥɸɫɧɢɤ
–I
ɜɯ
–I
ɜɵɯ
ɉɚɫɫɢɜɧɵɣ
U
ɜɯ
ɱɟɬɵɪɟɯ-
U
ɜɵɯ
ɩɨɥɸɫɧɢɤ
Ɋɢɫ. 5.1. Ɉɛɨɛɳɟɧɧɚɹ ɫɯɟɦɚ ȺȽ
(5.1)