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At a glance
Location: Kosova.
Sector: TransmissionDuty: Protection and control DCStandards: IEEE 485 sizing methodScope: Design, supply, commissioning
Projects / Utilities
Transmission substation, DC auxiliary system
In a substation the DC system is what allows protection to operate when the AC side is already in trouble. It is specified around the worst-case duty cycle, not around average load.
In the field
The installation, as delivered.
220 V DC rectifier and distribution cabinets for protection and control supply.
The brief
Provide a DC auxiliary system for protection relays, control, and switchgear operation, sized to the substation duty cycle including tripping and closing currents.
What we delivered
A duty-cycle calculation first, then equipment selected against it. Nothing was ordered before the load profile was agreed in writing.
- Duty-cycle sizing per the IEEE 485 method with margin for ageing and temperature
- Chargers with monitoring and alarm contacts wired to SCADA
- Battery racking, DC distribution, and labelling to plant standard
- Full commissioning records handed over as part of the asset file
Outcome
A DC system with a traceable design basis, so future load additions can be checked against the original calculation instead of guessed.
Related
Last reviewed: