3150 kVA Transformer In Power System-0.4/6.6 kV | South Africa 2025

Connecting the Future with Stable Current, Choose Distribution Transformer for Zero Interference!

01 General

1.1 Project Description

3150 kVA step up oil immersed distribution transformer was delivered to South Africa in 2025. The rated power of the transformer is 3150 kVA with ONAN cooling. The primary voltage is 0.4 kV, the secondary voltage is 6.6 kV with ±2*2.5% tapping range (NLTC), they formed a vector group of Dyn11.

This 3150kVA distribution transformer is primarily intended for use in solar power generation systems for efficient conversion and distribution of electrical power. Both high-voltage and low-voltage sides are equipped with dedicated cable boxes for safe cable connection and maintenance. Equipped with a sensitive gas relay that monitors the internal gas conditions of the transformer in real time, rapidly identifying internal faults and insulation failures. In the event of abnormal gas generation, the gas relay will quickly operate to cut off the power supply, preventing the escalation of accidents. A high-precision winding thermometer is installed to monitor winding temperature in real time and ensure operation within a safe temperature range. An oil temperature gauge is provided to monitor the temperature of the transformer oil, ensuring good heat dissipation performance and insulation effectiveness.

1.2 Technical Specification

3150 kVA step up oil immersed distribution transformer specification and data sheet

1.3 Drawings

3150 kVA step up oil immersed distribution transformer dimensions and weight details

02 Manufacturing

2.1 Core

The three-phase three-leg core design optimizes the magnetic circuit, improving the utilization of magnetic flux. As a result, the transformer can handle higher power levels with a smaller size and weight, demonstrating outstanding power density. The use of high-performance materials and precision manufacturing processes significantly minimizes hysteresis and eddy current losses, enhancing the energy efficiency of the transformer under load conditions, which aligns with modern energy-saving and environmental protection requirements.

2.2 Winding

The low voltage winding typically employs a foil design, using thin and wide copper or aluminum foils to form multiple parallel conductor paths. This design not only enhances overall mechanical strength but also effectively reduces the resistance of the winding. The high voltage is wire-wound and the thin wire with special insulation treatment can withstand high voltage without breakdown, ensuring the safe and stable operation of the transformer.

2.3 Tank

The tank is coated with a special corrosion-resistant and UV-resistant layer to meet the specific requirements of the solar power generation environment, ensuring its long-term stable operation. The design complies with protection class IP44 and above, effectively preventing dust and moisture ingress, safeguarding the equipment’s safety under outdoor conditions.

2.4 Final Assembly

Core Assembly: Securely assemble the core onto the base frame, ensuring the integrity of the magnetic circuit. Winding Installation: Install low voltage and high voltage windings in sequence, ensuring insulation and safety isolation. Cooling System Configuration: Install the cooling system (oil tank and radiators) and fill it with insulating oil to aid in heat dissipation. Electrical Equipment Connection: Connect the control panel, relays, and switches, ensuring proper insulation treatment. Enclosure Assembly: Install the protective casing, meeting IP protection class requirements to prevent dust and water ingress.

03 Testing

1. Measurement Insulation Resistance

2. Check of Voltage Ratio and Vector Group

3. Measurement of Winding Resistance

4. Separate-Source Power-Frequency Voltage Withstand Test

5. Induced Voltage Withstand Test

6. Measurement of No-load Losses and No-load Current

7. Measurement of Impedance Voltage and Load losses

04 Packing and Shipping

05 Site And Summary

Thank you for learning about our Distribution Transformer. We are committed to providing customers with efficient, safe, and reliable power solutions to help you optimize power distribution and reduce energy consumption. Whether you are in urban infrastructure, industrial production, or commercial buildings, our transformers can meet your needs and ensure stable power supply. For more information or inquiries, please feel free to contact our professional team. We look forward to collaborating with you to promote a sustainable future!