6MW 石化供电系统（2026年第三季度中国供应商价格）
6 MW Petrochemical Power System Cost Breakdown (Q3 2026 China Supplier Pricing) — itemized bill of materials and FOB pricing for a typical configuration.
Estimated total (FOB): $982,364 · 6300 kVA transformer
Bill of materials
| Item | Specification | Qty | Price (USD) |
|---|---|---|---|
| HV incoming panel (KYN28A-12-630-315) | 630 A / 31.5 kA · vacuum | 2 | $4,896 |
| HV bus-tie panel (KYN28A-12-630-315) | 630 A / 31.5 kA · vacuum | 1 | $2,448 |
| Main transformer (each) (S13-M-6300/10) | 6300 kVA · Oil-Immersed · Copper · S13 | 2 | $126,853 |
| LV incoming panel (MNS (drawer type)) | 4000 A busbar · In 9093 A | 2 | $26,546 |
| LV bus-tie panel (MNS (drawer type)) | 4000 A busbar | 1 | $13,273 |
| LV feeder panel (×5) (MNS (drawer type)) | distributes 30 circuits | 5 | $66,365 |
| Cable branch box (LV) (DFW-0.4) | 1-in / 4-out · 0.4 kV · 630 A | 7 | $4,410 |
| Main feeder cable (TX→LV) (YJV 0.6/1kV 300 mm² ×19) | 19× 300 mm² Cu · ΔU 1.24% @ 80 m · $154.0/m | 19 | $234,080 |
| Main feeder (custom/dual busway) (Busway > 6300 A) | LV current 9093 A exceeds the largest standard busway (6300 A) — custom busway or dual-run busway required; shown as parallel cables below | 1 | POA |
| Feeder cable — Process feeder 1 (×30) (YJV 150 mm²) | 150 mm² Cu · 304 A · ΔU 1.6% · $86.0/m | 30 | $206,400 |
| Branch trunk cable (LV → branch box 1) (YJV 240 mm² ×3) | 3× 240 mm² Cu · 1215 A · ΔU 1.3% · $123.0/m | 3 | $29,520 |
| Branch trunk cable (LV → branch box 2) (YJV 240 mm² ×3) | 3× 240 mm² Cu · 1215 A · ΔU 1.3% · $123.0/m | 3 | $29,520 |
| Branch trunk cable (LV → branch box 3) (YJV 240 mm² ×3) | 3× 240 mm² Cu · 1215 A · ΔU 1.3% · $123.0/m | 3 | $29,520 |
| Branch trunk cable (LV → branch box 4) (YJV 240 mm² ×3) | 3× 240 mm² Cu · 1215 A · ΔU 1.3% · $123.0/m | 3 | $29,520 |
| Branch trunk cable (LV → branch box 5) (YJV 240 mm² ×3) | 3× 240 mm² Cu · 1215 A · ΔU 1.3% · $123.0/m | 3 | $29,520 |
| Branch trunk cable (LV → branch box 6) (YJV 240 mm² ×3) | 3× 240 mm² Cu · 1215 A · ΔU 1.3% · $123.0/m | 3 | $29,520 |
| Branch trunk cable (LV → branch box 7) (YJV 150 mm² ×2) | 2× 150 mm² Cu · 608 A · ΔU 1.6% · $86.0/m | 2 | $13,760 |
| Main busbar (Cu) (Cu 125×10) | 125×10 · 2500 A rating · ref $147.8/m | included | POA |
| Grounding electrode (Φ20mm × 2.5m rod) | R₁ 39.6 Ω → 13 rod(s) ≤ 4 Ω | 13 | $125 |
| Detuned PFC capacitor bank (664 kvar) | automatic · 7% detuned · 0.4 kV | 1 | $8,300 |
| Series detuning reactor (7%) (46.5 kvar) | 189 Hz tuning · below 5th harmonic | 1 | $2,788 |
| Explosion-proof (Ex) distribution board (Ex d Zone 2) | Flameproof enclosure · IEC 60079 · quoted per project (POA — not included in estimate) | 1 | POA |
| Ex-rated motor control center (MCC) (Ex d Zone 2) | Ex motor starters + VFD for pumps/compressors · IEC 60079 (POA — not included in estimate) | 1 | POA |
| Emergency / standby diesel generator (2000 kVA) | life-safety / standby power · 1800 kVA required | 1 | $95,000 |
Single-line diagram
How it was calculated
- Continuous process load = 6,000 kW (N-1 continuity)
- Redundancy 2N → 2 independent power paths (2N)
- Rectifier harmonic source: 1,200 kW · THDi 25% → Ih = 2,309 × 25% = 577 A
- Detuned filter: Qc = 1,200 × (tanφ₁ − tanφ₂) = 664 kvar · 7% reactor (f_res 189 Hz)
- Resonance check: 5th harmonic 250 Hz above 189 Hz → detuned (safe)
- Loads: P=6,000 kW, PF 0.95, 30 circuits
- Demand: 6,000 × 0.85 = 5,100 kW
- PFC: Qc = 5,100 × (0.329 − 0.329) = 0 kVAR → 0 kVAR bank
- Transformer: S = 5,100 ÷ 0.95 = 5368.4 kVA → 6,300 kVA standard
- Loading: 5,368 ÷ 6,300 = 85% (good range)
- Voltage regulation: 85% × 4% × sinφ ≈ 1.1% at full load
- HV: In 363.7 A, Isc 28.9 kA → KYN28A-12-630-315
成本敏感因素
- 设备 — 变压器/开关柜/逆变器是最大单项。
- 储能 — 电池是最大变量。
- 铜价与运费 — 铜价联动线缆与运费使到岸成本 ±5–10% 波动。
常见问题
防爆（Ex）区域划分对电气设备意味着什么？
危险区按爆炸性气体（IEC 60079 的 Zone 0/1/2）或粉尘（Zone 20/21/22）出现的概率划分。Zone 1/2 内的电气设备须有与气体组别和温度等级匹配的 Ex 认证（如 Ex d、Ex e、Ex n）。正确选 Ex 等级会使开关柜成本增加 20-50%；计算器可选分区并标注 Ex 型 BOM。
石化厂为什么需要双电源供电？
连续流程装置（炼油、乙烯、合成氨）不能承受失电——重新开车可能需数天并损失数百万。按 GB 50052 负荷分级，关键负荷采用双路独立电源 + 自动转换（ATS）和 N+1 或 2N 冗余。计算器可设冗余等级并据此配置应急/备用回路。
石化厂的整流装置谐波如何处理？
电解和电镀整流器注入 5、7、11 次谐波。若公共连接点总谐波畸变超过 IEEE 519 限值（多数系统为 5% THD），需加装去谐电容器组（7% 串联电抗）或有源滤波器（APF）。计算器在 THDi 超过约 15-20% 时按 7% 去谐系数配置补偿。
石化中低压变压器典型阻抗是多少？
石化厂配电变压器阻抗通常 6%（uk），大型电机回路有时用 8% 以限制短路电流。阻抗越高短路电流越小但电压调整率越差，6% 对 10/0.4 kV、1000-2500 kVA 单元可兼顾两者。计算器计算故障水平时采用标准 uk 值。
GB 50052 对连续生产负荷如何分级？
GB 50052 将负荷分为一、二、三级。连续石化装置属一级负荷，需两路独立电源；关键安全负荷（紧急停车、消防泵）属『一级重要负荷』，还需柴发或 EPS 等应急电源。计算器的冗余与应急电源选项即对应这些分级。
炼厂工艺负荷的需用系数怎么定？
炼厂工艺负荷近乎连续运行，主装置需用系数高达 0.8-0.9，公用与辅助系统 0.6-0.7。2000 kW 装机工艺负荷、0.85 需用系数、0.95 功率因数约需 1790 kVA，取 2000 kVA 变压器。计算器用这些系数避免超配与欠配。