Calculateur de système électrique de parc industriel
Dimensionnez la distribution électrique d'une usine ou d'un parc industriel — charge totale des équipements, facteur de demande, part des moteurs et part des sources harmoniques, avec sélection des transformateurs et de l'appareillage, compensation réactive et BOM.
Les installations industrielles combinent des charges de moteurs, de chauffage et électroniques avec un facteur de puissance naturel inférieur à 0,9 et des harmoniques importantes. Ce calculateur transforme la charge des équipements raccordés en un ensemble dimensionné de transformateurs et d'appareillage, avec compensation réactive et filtrage des harmoniques selon GB 50052 et GB 50055.
Worked Examples
Example 1 — 2 MW Factory Load (Demand Factor, Motor & Harmonic Share) · FOB $257,923
Settings are illustrative starting points — confirm with a protection coordination study per IEC 60255 / IEEE 242.
📚 Calculation book
CALCULATION BOOK
1600 kVA - 10kV/0.4kV - single - illustrative
1. Load calculation
Standard: IEC 60076 - IEC 60364-5-52
Parameter
Formula
Value
Connected load
P = sum(kW)
2,000 kW
Demand factor
Kd
0.6
Demand power
Pd = P x Kd
1,200 kW
Power factor
cos(phi) before -> after
0.82 -> 0.95
Design apparent power
Sd = Pd / cos(phi)
1,263 kVA
Transformer loading
Sd / Srated
79%
2. Short-circuit calculation
Standard: IEC 60909
Parameter
Formula
Value
System impedance (pu)
Zs = S / Ssc
0.32% (on 1600 kVA base)
Transformer impedance
Zt = Z%
4%
Total impedance
Z = Zt + Zs
4.32%
LV prospective Isc
Isc = In / Z
53.5 kA
HV prospective Isc
Isc = Ssc / (sqrt(3) x V)
28.9 kA
Breaking check
Icu >= Isc
LV 65 kA (1.2x margin) PASS
3. Voltage drop
Standard: IEC 60364-5-52 Annex G
Parameter
Formula
Value
Main feeder
dU = sqrt(3) x I x L x R / V
300 mm2 - dU 1.20% @ 80 m
Limit
max 3%
within limit
Transformer volt. reg.
dU ~ loading x Z% x sin(phi)
1.0% at full load
4. Reactive power / harmonics
Standard: IEC 61921 (PFC) - IEEE 519 (harmonics)
Parameter
Formula
Value
Required compensation
Qc = Pd x (tan1 - tan2)
0 kvar
PFC bank
standard step
0 kvar
Detuned reactor
p = 6%
n/a
5. Grounding
Standard: IEC 60364-5-54 earthing arrangements and protective conductors LV earthing target 10 ohm (TN systems); 4 ohm used as a conservative design target - target 4 ohm
Parameter
Formula
Value
Single rod resistance
R1 = rho/(2 x pi x L) x ln(4L/d)
39.6 ohm
Rods required
n = R1 / (target x 0.8)
13 rod(s) <= 4 ohm
Rod spec
dia x length
20 mm x 2.5 m
This calculation book is illustrative it consolidates the computed values with the referenced standards. A licensed engineer must verify and seal final design documents for construction.
Cable & grounding pricing:Cable conductors and grounding are priced from the confirmed cables-trays-grounding price reference (per-metre copper YJV; aluminium remains POA). The main copper busbar is POA — its length is project-specific.
Busway (high-current feeders):For LV feeders above ~2500 A, a busway (母线槽) trunking system is recommended instead of parallel cables.
Demand factor:0.6 demand factor avoids oversizing — not all plant equipment runs simultaneously at full load.
Motor & harmonic load:60% motor load (natural PF 0.82); 25% harmonic-source load (detuned PFC is sufficient.)
Zone / plant metering:For multi-tenant parks, per-zone / per-plant revenue-grade metering (分区分厂计量) at the LV feeder enables sub-billing and energy accountability — quoted per project.
Harmonic sources:Typical harmonic sources: VFD drives (THDi ~30%), rectifiers / electroplating (~25–35%), UPS (~10–20%), welding machines and LED lighting. The 25% share is applied as an aggregate — a detailed equipment list refines APF sizing.
Transformer loading:Transformer sized at the target PF 0.95; final capacity must be confirmed against the actual equipment schedule.
Comment cela a été calculé
Comment fonctionne le dimensionnement
Demande P = charge raccordée × facteur de demande Kd (tous les équipements ne fonctionnent pas simultanément). La part des moteurs détermine le facteur de puissance naturel ; la compensation réactive Qc = P × (tanφ₁ − tanφ₂) le corrige vers le PF cible. La part des sources harmoniques donne le courant harmonique Ih = I₁ × THDi, filtré par une batterie de condensateurs désaccordée.
Normes applicables
Le dimensionnement fait référence à GB 50052 (conception de l'alimentation électrique), GB 50055 (conception de la distribution basse tension industrielle), GB/T 14549 (harmoniques) et IEC 60076 (transformateurs).
Questions fréquentes
What demand factor applies to an industrial park?
An industrial park with many factories never runs every machine simultaneously; a demand factor of 0.55-0.7 is typical. A 2000 kW connected load at 0.6 kd and 0.9 pf gives ~1330 kVA demand, so a 1600 kVA Transformer or two 800 kVA units suit. The calculator uses demand factor and motor share to size the MV/LV plant.
How much harmonic filtering does a factory-heavy park need?
When 60% of load is motors on VFDs and 25% is non-linear (rectifiers, UPS), THDi can reach 15-25%. IEEE 519 limits THD to 5-8% at the point of common coupling, so a detuned capacitor bank (7% Reactor) or APF is required. The calculator sizes compensation and detuning from the harmonic share.
What is the standard MV/LV architecture for an industrial park?
Typical architecture: 10 kV (or 35 kV) utility feed -> ring or radial MV Switchgear -> one transformer per factory or block -> 0.4 kV switchboards -> motor control centers. A 10 kV ring with RMUs along the ring offers N-1 supply. The calculator sizes the transformers, switchgear and compensation for the aggregated park load.
How do I allocate transformer capacity per factory?
Give each factory its own transformer sized to its demand plus 20-25% headroom, or share one large transformer for small tenants. Separate transformers isolate faults and simplify metering, but shared units cost less. The calculator aggregates the park demand and shows the single-transformer and split-transformer options.
What power factor should an industrial park maintain?
Utilities usually require 0.9-0.95 Power Factor and levy penalties below ~0.9. Industrial parks with motor-heavy load typically start at 0.75-0.85 and add capacitor banks to reach 0.95. The calculator computes the required kvar compensation to correct from measured pf to target and sizes the LV capacitor bank.
What redundancy does a park MV network usually provide?
A ring-main MV network with normally-open tie provides N-1 redundancy: any cable or RMU fault is isolated and load restored from the other direction. Radial feeders are cheaper but lose supply on a fault. The calculator's architecture notes cover ring vs radial options and their reliability trade-off.
Intégrer ce calculateur
Copiez le code iframe ci-dessous pour intégrer ce calculateur sur n'importe quel site. La page intégrée est en noindex et s'adapte à toute largeur.
Les résultats sont des estimations d'ingénierie à titre indicatif. La conception finale doit être confirmée par un ingénieur local agréé en fonction des conditions du site et des codes applicables. Les prix sont FOB Qingdao (EXW) et n'incluent pas le fret, les droits de douane ou l'installation.
Send my complete design report
Get the full bill of materials, single-line diagram, calculation steps and FOB pricing as a PDF — free, no sign-up.
Your data stays private. No spam — only a reply to your enquiry.