Substation Engineering Case Studies: Design, Protection & System Studies

Below are four flagship projects showcasing greenfield substation design and advanced power system studies delivered by Keentel Engineering.

where Keentel Engineering delivered end-to-end substation design (primary, secondary) and comprehensive power system studies to ensure safe, reliable, and standards-compliant installations.

These projects reflect Keentel Engineering’s portfolio of utility scale substation design work, spanning EHV transmission, collector substations, and bulk power facilities. Each case demonstrates how substation engineering and power system studies for substations are applied together to support greenfield development, system expansion, and long-term grid reliability.

345 kV EHV Greenfield Substation

Project Scope

Design and build of a new 345 kV / 138 kV transmission substation to integrate 400 MW of wind generation into the regional grid.

This 345 kV project represents a full greenfield substation design, addressing site layout, equipment clearances, grounding, and protection from first principles. Substation design for greenfield projects at this voltage level requires coordinated EHV power system studies to validate short-circuit duty, reactive power performance, and system stability prior to energization.

The 345 kV greenfield substation design highlights best practices in transmission integration, grounding, and protection engineering.

Primary Design Services

• Full primary layout (GA) drawings with major equipment placement and conductor routing
• Transformer, breaker, disconnect switch, CT/VT, and wave-trap specifications
• 4 000 A tubular aluminum rigid bus design
• IEEE Std 80™ grounding grid analysis using CDEGS
  

Secondary Design Services

• Protection & control single-line diagrams and wiring schematics
• AC/DC auxiliary systems with IEEE Std 485™ battery sizing
• RTU/SCADA integration: point mapping and telemetry configuration

Power System Studies

• Short-circuit (IEEE C37.010)
• Load flow & reactive power planning
• Protection coordination (SEL-411L, SEL-351, SEL-487E)
• Arc-flash hazard analysis (IEEE 1584-2018)
• Ground grid step/touch voltage assessment

Key Deliverables & Impact

• 150+ IFC drawing sets & equipment BOM
• PE-sealed engineering certification in multiple states
• Successful substation energization with zero safety incidents
• “Proactive RFI responses” earned ongoing preferred-partner status

230 kV GIS Substation Expansion

Project Scope

Expansion and modernization of an existing 230 kV gas-insulated substation, adding two new feeders and upgrading legacy protection.

Primary Design Services

• 3D CAD-based GIS bay layout modifications
• New feeder bay and duct-bank routing
• Civil coordination for control building enlargement

The 230 kV GIS scope placed particular emphasis on optimized 230 kV substation layout design within an existing footprint. Careful coordination between physical layout, protection zones, and operational access was required to support a phased substation expansion design without interrupting in-service equipment.

Secondary Design Services

• IEC 61850 digital protection scheme design
• Microprocessor relay replacements (SEL/GE)
• Digital fault recorder (DFR) installation and disturbance monitoring

Power System Studies

• Breaker duty analysis
• Relay coordination & selectivity for transmission line protection
• Transient stability (NERC TPL)
• EMTP modeling for breaker TRV assessment

Key Deliverables & Impact

• Updated one-line, three-line, and P&C schematics
• Comprehensive settings database
• Arc-flash labeling across new and retrofitted equipment
• Expansion completed without any substation outage, earning additional retrofit work

115 kV / 34.5 kV Collector Substation (BESS)

Project Scope

EPC-level design for a 100 MW / 400 MWh battery energy storage collector substation tying into a 115 kV network.

As a utility-interconnected collector substation design, this project illustrates how medium-voltage collection systems and high-voltage interfaces are engineered together. Collector substations supporting BESS projects must balance protection sensitivity, control integration, and future expandability.

The 115 kV BESS collector substation demonstrates how collector substation design supports renewable integration and grid stability.

Primary Design Services

• Space-optimized layout under site constraints
• Single-bus configuration with future breaker-and-a-half provision
• 75–125 MVA transformer with on-load tap changer

Secondary Design Services

• Transformer differential (87T) and bus protection (87B) schemes
• BMS integration for trip signaling
• Dual-fiber protection & redundant SCADA architecture

Across all projects, substation protection design and SCADA and P&C substation design were treated as system-level functions rather than standalone tasks. This approach ensured consistent protection philosophy, dependable communications, and seamless integration with utility operations and ISO requirements.

Power System Studies

• Load flow for capacitor bank optimization
• Fault analysis including BESS short-circuit contribution
• Harmonic study for IBR interactions
• EMT switching transient analysis for inverter protection

Key Deliverables & Impact

• IFC drawings & FAT support docs
• Detailed commissioning & relay-setting plans
• First large-scale BESS substation for the client, delivered in under 12 months
• Performance exceeded interconnection guarantees

500 kV Bulk Power Substation

Project Scope

This 500 kV bulk power substation design enhances transmission capacity and ensures reliable interregional power transfer.

on a major interregional corridor, enhancing transfer capability by 1 200 MW.

Bulk power substations at the 500 kV level play a critical role in regional transfer capability and contingency performance. Utility substation designat this scale demands rigorous coordination between physical design, protection schemes, and interconnection studies to meet NERC reliability criteria.

Primary Design Services

• Breaker-and-a-half arrangement
• 500 kV gas circuit breaker & disconnect switch specifications
• High-ampacity rigid/strain bus with seismic considerations

Secondary Design Services

• High-speed fiber-based bus differential protection
• Line differential & distance protection coordination
• N-1/N-2 redundant protection zoning

Power System Studies

Ensure accurate system validation with our power system studies services for load flow, fault analysis, and grid compliance.

• Interconnection SIS modeling
• EMT study for breaker restrike/TRV risks
• GIC impact assessment (NERC TPL-007)
• NERC TPL reliability assessment

Key Deliverables & Impact

• 400+ page Engineering Study Report & IFC drawings
• FAT/SAT checklists, commissioning manuals, and staff training
• Early energization ahead of compliance deadlines, securing client recognition

Why Clients Choose Keentel Engineering

• Integrated Primary & Secondary Design under one roof
• Advanced Modeling & Studies: PSSE, PSCAD, EMTP, CDEGS
• NERC & IEEE Expertise: PRC, TPL, 1584, 80, 485, 2800 compliance
• First-Time ISO Acceptance with minimal RFIs
• Repeat Business driven by reliability, responsiveness, and precision

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Explore our Electrical Substation Design Services and partner with Keentel Engineering to deliver turnkey, standards-compliant substations—on time and on budget.