225 kV / 90 kV Primary Transmission Substation Expansion
Comprehensive turnkey expansion and retrofitting of an essential high-voltage grid hub connecting primary regional industrial corridors with cross-border power transmission routes.
- Client Authority
- Regional Transmission System Operator
- Voltage Level
- 225 kV / 90 kV Transmission
- Nominal Capacity
- 2 × 120 MVA Autotransformers
- Project Timeline
- 18 Months Turnkey
Engineering Challenge
The project required executing brownfield construction adjacent to live 225 kV transmission busbars with zero unplanned outages to surrounding industrial consumers, coupled with severe summer ambient temperatures exceeding 48°C.
T Afrik Executed Solution
T AFRIK engineered a staged modular cut-over sequence using pre-commissioned digital protection relays and temporary bypass feeders. We coordinated factory witness testing of dual 120 MVA autotransformers and oversaw heavy-haul transport from port to site.
Technical Scope & Commissioning Highlights
- Gas-insulated switchgear (GIS) expansion with SF6 density telemetry
- IEC 61850 substation automation architecture with redundant optical rings
- High-voltage dielectric and partial discharge (PD) testing on site
- Integration with national dispatch SCADA protocols
Validated Project Metrics
- Installed Capacity
- 240 MVA Total
- Availability Factor
- 99.98%
- Unplanned Outages
- Zero (0) Hours
