Q: Kuv yuav tsum tau kuaj 220 kV cable, 8 km ntev. Kuv xav tau qhov ntsuas SR li cas?
A: 7-kauj ruam sizing txheej txheem: txiav txim siab xeem → xam C → kwv yees L → xam f_res → txheeb xyuas kev ntaus nqi → iterate → finalize.
Kauj ruam-by- kauj ruam - 220 kV cable, 8 km:
1. IEC 60840: V_test=2.0 × 127 kV=254 kV. Duration 60 min.
2. C≈ 8 km × 0.2 μF/km=1.6 μF.
3. Xav txog 3 × 100 kV/2 A reactors nyob rau hauv parallel: L=26.7 H, f=24.4 Hz.
4. Tam sim no ntawm 254 kV: I=V × 2πf × C=6.9 A. Tab sis 3 × 2A → 6A tag nrho → NOT OK.
5. Hloov kho rau 3 × 100 kV / 4 A reactors: tag nrho kuv=12 A → OK. P_in=254 × 6.9 / 35=50 kW.
6. Tag nrho qhov hnyav: 3 × 450 kg + 200 + 150 + 100=~ 1,800 kg.
Sizing summary rau common scenarios:
|
Scenario |
V_test (kV) |
C (μF) |
f (Hz) |
Pom zoo System |
|
33 kV kab, 3km |
48 |
0.6 |
45 |
60 kV / 2A × 1, 5 kW |
|
110 kV kab, 5 km |
160 |
1.0 |
24 |
200 kV/4A × 2, 20 kW |
|
220 kV kab, 8 km |
254 |
1.6 |
24 |
300 kV / 4A × 3, 50 kW |
|
400 kV kab, 5 km |
330 |
1.0 |
48 |
400 kV/2A × 2, 25 kW |
|
GIS 245 kV, 10 bays |
230 |
0.05 |
80 |
300 kV/1A × 2, 5 kW |
|
Generator 100 MVA |
28 |
2.5 |
45 |
30 kV/5A, 10 kW |
Cov lus ceeb toom tseem ceeb:
• +20% margin ntawm reactor voltage ntsuas . +30% margin ntawm qhov ntsuas tam sim no.
• Yog tias P_in> 100 kW, xav txog kev kuaj xyuas (tso cai los ntawm cov qauv feem ntau).
• Q Tiag Tiag yuav qis dua li qhov kwv yees - kev npaj txuag kom tsis txhob muaj qhov ua tsis tiav.