Clean Energy Collection Line and Grid Integration Reliable Epoxy Resin Cast Dry Type Transformer 800 kVA 400 V to 20 kV

The 800 kVA epoxy resin cast dry type transformer is engineered for step-up duty in renewable energy projects. It converts 400 V low voltage from solar inverters or wind turbine generators to 20 kV medium voltage, enabling efficient connection to site collection lines and integration with the local grid. This three-phase cast resin unit eliminates liquid insulation, providing a cleaner, safer, and maintenance-friendly solution for photovoltaic and wind farm substations.

• Zero Liquid Insulation Design – Airtight epoxy resin encapsulation of HV and LV windings removes fire and leakage risks, making it ideal for environmentally sensitive and densely equipped renewable energy zones.
• Strong Grid Adaptability – Built to handle the intermittent output of solar and wind sources, with high short-circuit withstand and reliable performance during frequent load cycling and voltage fluctuations.
• Enhanced Harmonic Tolerance – Winding and core design mitigates additional heating caused by inverter-generated harmonics, keeping temperature rise well within Class F or H limits.
• Compact Step-Up Substation Ready – Space-saving layout simplifies integration into containerized or skid-mounted step-up stations, reducing civil work and onsite installation time.
• Long Service Life with Minimal Intervention – The moisture-proof and dirt-resistant cast construction ensures stable operation in coastal, desert, or high-humidity climates without routine oil testing or filtration.

In utility-scale photovoltaic and wind power plants, the transformer connects 400 V inverter outputs or generator terminals to a 20 kV collector network. Our design addresses the unique operating stresses of clean energy generation:

• Voltage Build-Up from 0.4 kV to 20 kV – The Dyn11 vector group efficiently transforms low inverter voltage to grid-compatible medium voltage while handling the neutral earthing scheme required by the collection system.
• Intermittent Loading & Thermal Cycling – The dry type cast resin windings have high mechanical strength and uniform thermal expansion, preventing cracking or insulation degradation under daily load swings.
• Harmonic Current Handling – Doubled neutral capacity and specially transposed conductors manage triple harmonic circulation common in inverter-based PV and wind converters, thereby reducing hot spots.
• Harsh Outdoor Installation – With an IP44 ventilated enclosure, the transformer can be placed directly beside inverters or inside pad-mounted step-up stations, protected from sand, salt spray, and heavy rain.
• Grid Interconnection Compliance – The unit adheres to relevant ride-through and power quality requirements, supporting stable reactive power exchange and voltage ride-through during grid disturbances.

Cast resin transformers remove the risk of oil leaks and fire, which is critical when equipment sits close to inverters, battery containers, or vegetation. They also require no oil containment pit, lowering civil costs and environmental liability.

The 400 V winding utilizes a reinforced neutral bar and careful conductor transposition to suppress circulating harmonic currents. Combined with high-temperature insulation, it safely absorbs extra heating without accelerated aging.

Yes. Standard models are rated for up to 1000 m altitude and 40°C ambient. We provide specially rated units for sites above 4000 m and in 55°C environments, adjusting creepage distances and cooling accordingly.

Under normal conditions, only periodic visual inspection, cleaning of ventilation grills, and checking of cooling fans (if fitted) are necessary. There is no oil sampling, filtering, or regasketing required throughout its service life.

A weatherproof IP44 enclosure with anti-corrosion coating shields the core and windings from rain, dust, and UV exposure. Internal forced air cooling with thermostatic control maintains safe temperatures even in strong sunlight.

It is manufactured to meet IEC 60076-11 as a minimum, and can be customized to satisfy national grid codes regarding short-circuit impedance, voltage regulation, and partial discharge limits for renewable energy interconnection.