HJ-VPI Series Vacuum Pressure Impregnated Transformer
Class H/C Insulation / 100% Recyclable / High Overload Capacity
The HJ-VPI Series Vacuum Pressure Impregnated Transformer is the premier eco-friendly power solution for modern green infrastructure. Manufactured using advanced VPI technology, the windings are thoroughly impregnated with high-temperature varnish, delivering exceptional thermal dissipation and fire resistance. Unlike cast resin transformers, the HJ-VPI is fully repairable and 100% recyclable at the end of its lifecycle, perfectly aligning with strict global ESG (Environmental, Social, and Governance) mandates.
Ideal for Eco-Conscious & Heavy-Load Applications:
- ✓ Marine, Offshore Platforms & Wind Turbines
- ✓ Green Commercial Buildings & LEED-Certified Projects
- ✓ Underground Subways, Mining & Rail Transit
- ✓ Industrial Plants requiring high temporary overload
1. Advanced VPI Technology & Class H/C Insulation
Our coils are processed in a highly controlled Vacuum Pressure Impregnation (VPI) chamber using premium polyester or silicone varnishes. This ensures deep penetration into the winding layers, eliminating air voids. Utilizing Nomex® or equivalent high-temperature materials, the transformer achieves an outstanding Class H (180°C) or Class C (220°C) insulation rating, confidently handling extreme thermal stresses.
2. Ultimate Eco-Friendliness & Repairability
Designed with the circular economy in mind. Unlike epoxy-cast transformers which become hazardous solid waste, the HJ-VPI contains no solid encapsulation. At the end of its 30+ year lifespan, the copper/aluminum conductors and silicon steel core can be easily dismantled and 100% recycled. Furthermore, individual damaged coils can be repaired rather than scrapping the entire unit.
3. Global Voltage Matching & Superior Overload
We configure the HJ-VPI to flawlessly integrate with your local utility grids (e.g., 11kV, 13.8kV, 20kV, 33kV). Thanks to the open-wound VPI structure, natural air convection is highly efficient. When paired with an AF (Air Forced) cooling fan system, it can safely sustain temporary overloads of up to 20% to 30% above its nominal rating without risking insulation breakdown.
4. High Mechanical & Short-Circuit Strength
The entire core-and-coil assembly is mechanically reinforced and baked during the curing process, creating a rigid, moisture-resistant monolithic structure. This robust construction provides excellent resistance to electrodynamic forces during short-circuit events and ensures stable operation in environments subjected to severe vibrations.
Global Factory Acceptance & Turnkey Support
Every HJ-VPI transformer undergoes rigorous factory acceptance testing (FAT) strictly compliant with IEC 60076-11 standards. We verify partial discharge limits, insulation resistance, and dielectric integrity. Units can be supplied in standard IP00 format for switchgear integration, or enclosed in custom IP20 to IP44 NEMA-equivalent protective housings for diverse site conditions.
Performance Matrix & Technical Specifications
(Note: The matrix below outlines our standard capacities up to 2500kVA for VPI Dry-Type Transformers. Specific voltages, enclosure IP ratings, and custom dimensions are fully adaptable to meet your local utility requirements.)
| Parameter / Rated Power | 100kVA | 500kVA | 1000kVA | 1600kVA | 2500kVA |
|---|---|---|---|---|---|
| Primary Voltage | Up to 35kV (e.g., 10kV, 11kV, 13.8kV, 20kV, 33kV) | ||||
| Secondary Voltage | 0.4kV / 0.415kV / 0.433kV / 0.480kV / 0.69kV | ||||
| Cooling Mode | AN / AF | AN / AF | AN / AF | AN / AF | AN / AF |
| Typical Impedance (%) | 4.0% | 4.0% | 6.0% | 6.0% | 6.0% |
| Vector Group | Dyn11 / Yyn0 / Custom Configurations | ||||
| Insulation Class | Class H (180°C) / Class C (220°C) | ||||
| Enclosure Rating Options | IP00 (Core only) / IP20 (Indoor Box) / IP23 (Outdoor Weather-proof) | ||||
| Compliance Standards | IEC 60076-11 / IEEE C57.12.01 | ||||
General System Ratings
- ESG & Environmental Impact: 100% Recyclable. Free of toxic solids, ensuring zero disposal liabilities at end-of-life.
- Cooling Capacity Boost (AF Mode): Forced air cooling safely increases rated capacity by up to 20%-30% to handle peak demands.
- Moisture & Fire Resistance: Non-flammable, self-extinguishing materials compliant with highest fire safety codes.
- Temperature Controller: Integrated PT100 sensors embedded in windings with digital display and alarm/trip contacts.
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