Solar Inverter Transformers & Net-Metering 11kV Substation EPC
TransfoLine manufactures specialized multi-winding inverter-duty step-up transformers (500 kVA to 5,000 kVA / 0.8kV to 11kV/33kV) with electrostatic copper shielding, harmonic derating, and turnkey NEPRA net-metering grid synchronization for industrial rooftop and ground-mounted solar plants across Pakistan.
Engineered specifically for solar inverter duty.
Standard distribution transformers suffer rapid harmonic breakdown on solar loads. TransfoLine inverter-duty units are custom-designed for 30+ years of high-yield solar generation.
Standard solar transformer ratings & configurations.
Standard Step-Up Capacities for 500kW to 5MW Solar Plants
TransfoLine manufactures both oil-immersed (ONAN/ONAF) and cast-resin dry-type solar step-up transformers tailored to utility and captive industrial setups:
| Solar Plant Capacity | Transformer Rating | Voltage Ratio | Secondary Inputs | Typical Application |
|---|---|---|---|---|
| 300 kW – 500 kW | 630 kVA | 0.4kV / 0.8kV to 11kV | Single / Dual | Cold storages, flour mills, commercial plazas |
| 1.0 MW (1000 kW) | 1,250 kVA | 0.8kV to 11kV / 33kV | Dual Split Winding | Textile spinning & weaving mills, steel re-rolling |
| 2.0 MW (2000 kW) | 2,500 kVA | 0.8kV to 11kV / 33kV | Quad Split Winding | Large composite complexes, cement grinding |
| 3.0 MW – 5.0 MW | 3.5 MVA – 6 MVA | 0.8kV to 33kV / 66kV | Multi-Inverter Central | Independent Solar IPPs, Industrial SEZ Parks |
From SLD design to commercial green meter energization.
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01
Grid Study
Load Flow & Fault Level Analysis
Assessing DISCO 11kV feeder capacity, harmonic resonance, and vector group matching for solar synchronization.
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02
Equipment Fabrication
Multi-Winding Transformer Supply
Manufacturing 100% pure copper inverter step-up unit with electrostatic shielding, VCB panel, and surge arresters.
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03
Protection Setup
Anti-Islanding & Bi-Directional Meter
Wiring reverse power relays, directional overcurrent, and calibrated utility-grade green meter for net-metering accounting.
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04
Energized
DISCO Testing & Final NOC
Joint inspection with LESCO/KE/FESCO engineers, protection trip test, and official commercial solar net-metering activation.
Solar substation engineering FAQ.
Answers to critical questions regarding solar inverter transformers, net-metering, and grid protection in Pakistan.
HARMONICS How do solar inverter harmonics affect transformers?
High-frequency pulse-width modulation (PWM) switching produces harmonic currents (especially 5th, 7th, 11th, and 13th orders) that increase core eddy losses and coil hot spots. TransfoLine uses K-factor reinforced conductors and electrostatic copper shields to eliminate harmonic overheating.
NET-METERING What are the DISCO requirements for 11kV industrial solar net-metering?
DISCOs require a dedicated 11kV VCB switchgear with calibrated PT/CT metering units, bi-directional 4-quadrant green meters, zero-export controllers (if unapproved for export), and anti-islanding protection relays (IEEE 1547 compliant).
PAYBACK What is the payback period for an industrial solar substation in Pakistan?
At current Pakistani industrial grid tariffs (PKR 42–55 per kWh), a 1 MW solar plant equipped with a dedicated TransfoLine step-up transformer achieves full capital payback within 2.8 to 3.2 years.
WARRANTY What warranty does TransfoLine provide on solar transformers?
Every TransfoLine solar inverter-duty transformer is backed by a 12-month complete replacement warranty and 24/7 on-site emergency engineering field support.
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Planning a 500kW to 5MW Solar Installation?
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