High Efficiency Three Phase Cast Resin Dry type Transformer 100kVA 10kV/0.4kV for Solar & Wind Power Integration and Plant Auxiliary Supply

The Three-Phase Cast Resin Dry-Type Transformer rated 100 kVA, with a voltage ratio of 10 kV to 0.4 kV, is specifically engineered for renewable energy grid integration and industrial plant auxiliary power systems. Utilizing class F or H epoxy resin encapsulated windings, this transformer delivers exceptional electrical performance, inherent fire safety, and environmental resilience. Its design meets the demanding requirements of solar photovoltaic (PV) power stations, wind turbine generator integration, and auxiliary supply for power plants, refineries, and manufacturing facilities. As a dry-type transformer, it eliminates oil-leak risks and reduces maintenance, making it an ideal choice for installations near sensitive equipment or within confined indoor spaces.

• High Efficiency & Low Losses: Optimized core design using grain-oriented silicon steel and precise winding configurations minimize no-load and load losses, lowering operational costs and improving energy yield for renewable projects.
• Fire Safety & Environmental Protection: Cast resin insulation is self-extinguishing and produces no toxic fumes. With no insulating oil, the transformer eliminates fire hazard and soil contamination risks, meeting stringent fire codes for indoor and rooftop installations.
• Robust Environmental Tolerance: Epoxy encapsulation provides excellent resistance to moisture, dust, and corrosive atmospheres (C2/E2 environmental classes), ensuring reliable operation in coastal wind farms, desert solar plants, or polluted industrial areas.
• Bidirectional Power Flow & Voltage Adaptability: Designed for both step-up (0.4 kV to 10 kV for solar/wind feeding into the grid) and step-down (10 kV to 0.4 kV for plant auxiliary loads) operation, with off-circuit tapping links for voltage regulation.
• Low Partial Discharge & Harmonic Resilience: Advanced vacuum casting process guarantees minimal partial discharge (<10 pC), while reinforced insulation and conductor design withstand voltage distortions commonly present in inverter-fed renewable energy systems.

• Rated Power & Voltage: 100 kVA, primary 10 kV (with ±2*2.5% tapping range), secondary 0.4 kV (line-to-line 400 V), three-phase, 50/60 Hz compatible.
• Insulation & Temperature Rise: Insulation class F or H, temperature rise limited to 100 K/125 K. Vacuum-cast epoxy resin ensures bubble-free solid insulation; partial discharge level <10 pC.
• Cooling Method: AN (air natural) as standard; optional AF (air forced) with fans for increased overload capability.
• Enclosure & Protection: IP00 indoor open-type execution; optional IP21, IP23 or IP54 enclosures for outdoor containerized substations or exposed locations.
• Vector Group: Dyn11 (standard, recommended for solar inverter outputs) or Yyn0, providing a path for triplen harmonics and managing unbalanced loads.
• Efficiency & Losses: Compliant with IEC 60076-11 and equivalent high-efficiency regulations. Typical losses (copper winding): no-load loss approx. 240 W, load loss approx. 1850 W at 75°C.
• Monitoring & Protection: Provision for PTC thermistors and embedded temperature controller with alarm and trip contacts, enabling seamless SCADA or plant control system integration.
• Materials: High-grade grain-oriented silicon steel core, copper foil windings (aluminum optional), rigid steel base frame with lifting lugs and bi-directional rollers.

Common requirements in solar and wind projects: voltage fluctuation, harmonic currents from inverters, frequent load switching, and the need for reliable auxiliary power. Installations are often in remote or coastal environments with high humidity, salt spray, or abrasive dust. Our transformer addresses these conditions with the following design measures:

• Harmonic Mitigation: Increased conductor cross-section and double-layer insulation manage additional heating caused by harmonic currents (up to THD 15%). The core operates at reduced flux density to avoid saturation under distorted waveforms.
• Voltage Adaptation: A ±2*2.5% off-circuit tapping on the HV side compensates for grid voltage variation, keeping the 0.4 kV output within acceptable limits for sensitive auxiliary equipment.
• Inrush & Mechanical Strength: Reinforced winding clamping and robust core construction withstand repeated magnetizing inrush currents and motor starting surges without mechanical degradation.
• Corrosion & Moisture Protection: For coastal or high-humidity sites, metallic parts receive anti-corrosion coating; cast resin inherently resists moisture. IP54 enclosures protect against blowing sand and rain.
• Unattended Operation & Integration: Standard temperature monitoring with potential-free contacts interfaces directly with plant PLC/DCS, enabling automatic forced cooling or emergency shutdown — critical for remote renewable energy stations.

• Q1: Can this transformer be used for both step-up and step-down in a solar PV plant?
  A: Yes. It is bi-directional — stepping up the inverter’s 0.4 kV output to 10 kV for grid export, and stepping down from the medium-voltage grid to supply plant auxiliary loads.
• Q2: What environmental conditions does the cast resin insulation withstand?
  A: It meets E2 (high humidity/condensation) and C2 (corrosive atmosphere) environmental classes. With an appropriate IP enclosure, it operates reliably in coastal wind farms, dusty deserts, or chemical plant surroundings.
• Q3: How does the transformer handle inverter-generated harmonics?
  A: The design integrates extra thermal margin in the windings and a lower flux density core. The Dyn11 vector group traps triplen harmonics, reducing insulation stress and additional heating.
• Q4: What maintenance is required for a dry-type transformer?
  A: Maintenance is minimal — periodic visual inspection, cleaning of cooling ducts, and checking terminal connections. No oil sampling or replacement is needed. The temperature controller should be tested annually.
• Q5: Can this transformer be installed outdoors without a building?
  A: Absolutely. By adding a weatherproof enclosure (IP54 or higher) and anti-condensation heaters, the transformer can be mounted on a concrete pad or within a solar skid, eliminating the need for a dedicated indoor room.
• Q6: What documentation supports EPC project approval?
  A: We supply dimensional drawings, heat loss tables, routine and type test reports per IEC 60076-11, and material certificates — facilitating your project’s compliance and approval workflow.

Request a customized quotation for your next solar or wind venture — reach out today for dedicated technical support and reliable lead times.