Substation Design — AIS & GIS, 11 kV to 500 kV

Network owners and developers need substation designs that pass utility review first time, interface cleanly with OEM equipment and can be built safely without late redesign. Gaps between primary, secondary and civil disciplines are the most common cause of rework and programme slip.

• Primary design: single-line diagrams, general arrangements, sections, busbar and conductor sizing
• Earthing grid design and step/touch potential assessment
• Lightning protection and insulation coordination
• Secondary design: protection, control and metering schematics, wiring and cable schedules
• Auxiliary AC/DC supply design and battery sizing
• Equipment specification, technical evaluation and vendor document review

• Network connection offer and fault levels
• Site survey, geotechnical report and soil resistivity data
• Client / utility design standards and preferred-equipment lists
• Protection philosophy and SCADA point requirements
• Environmental and planning constraints

• Single-line and operating diagrams
• General arrangement and section drawings
• Earthing design report with step/touch results
• Protection, control and wiring schematics
• Cable schedules and bill of materials
• Equipment specifications and technical schedules
• Design report and IFC drawing set

• AutoCAD / AutoCAD Electrical
• CDEGS or equivalent for earthing
• ETAP or DIgSILENT PowerFactory for supporting studies

1. Stage 1

   Concept

   Confirm connection requirements, layout options and key risks.

2. Stage 2

   Preliminary design

   Develop SLD, GA and earthing concept; hold first SiD workshop.

3. Stage 3

   Detailed design

   Complete primary and secondary packages and coordinate interfaces.

4. Stage 4

   Issued for construction

   Final checks, utility approval and IFC release.

5. Stage 5

   Construction support

   RFIs, design changes and as-built updates.

1. 1.Originator prepares the deliverable
2. 2.Independent checker verifies calculations, drawings and assumptions
3. 3.Discipline lead approves for issue
4. 4.RPEQ / chartered engineer sign-off where required by jurisdiction or client

• DNSP connection and design standards (e.g. Ausgrid, Endeavour, Essential, Energex/Ergon, Powercor, SA Power Networks)
• TNSP requirements (e.g. Transgrid, Powerlink, AusNet, ElectraNet, TasNetworks)
• AEMO / National Electricity Rules Chapter 5 connection obligations
• Network operator access, switching and permit-to-work rules

• Design checklists per discipline
• Drawing register with revision control
• Inter-discipline check before each gate
• Client and utility comments logged and closed out

• Safety in Design (SiD) workshops and hazard register
• HV access, isolation and permit-to-work compliance
• Safe Work Method Statements for high-risk construction work
• Exclusion zones, step/touch potential and induced voltage controls

• Secure substation network architecture aligned to IEC 62351
• Segregation of protection, control and corporate networks

• Material efficiency and reduced site rework
• Waste segregation and recycling on site
• Embodied-carbon awareness in equipment selection
• SF6-free or low-GWP switchgear options assessed where available

• Design decisions recorded against asset life-cycle cost (ISO 55001)
• Asset data and as-built records handed over in client asset-register format
• Maintainability and spares strategy considered at design stage

• Civil and structural
• Protection and settings
• SCADA and communications
• OEM equipment suppliers
• Transmission line / cable designers

Indicative only — actual programme depends on scope, approvals and outage windows.