10MVA 33KV Power Distribution Substation

Project type: power distribution substation project 
Project time: 2025-5-8 
Project location: South Africa 
Solution: 10mva 33/6.6kv transformer and switchgear 
This project is a power distribution station project for an industrial park in South Africa. The project includes 2×10MVA 33/6.6kV transformers and supporting switchgear products. It adopts the "design-supply-guidance" integrated solution to successfully improve the power supply reliability of the park to 99.99%. 
The project was completed in May 2025

Core equipment technical solution

1. Power transformer system 
Equipment Technical parameters Innovative design 
10MVA 33/6.6kV transformer Impedance voltage 8%±10% Dual radiator group + intelligent air cooling system 
No-load loss ≤9.5kW Corrugated oil tank explosion-proof structure (pressure relief valve) 
Temperature rise limit 55K (EN 60076) Built-in IoT monitoring module (partial discharge + oil temperature) 

2. Switchgear equipment 
33kV RMU (with fuse transformer feeder)

Fully insulated gas cabinet (SF6 alternative)

Transfer current 25kA/3s

Mechanical life>10,000 times

6.6kV secondary circuit breaker

Vacuum circuit breaker (rated breaking 20kA)

Mechanical interlock to prevent misoperation

6.6kV feeder circuit breaker (×5)

Digital protection device (overcurrent/grounding/differential)

Arc protection action time <2ms