Description

Challenge: Strengthening Power Continuity in the Heart of Skopje

Rapid urban development, increasing electricity demand and ageing infrastructure had placed growing pressure on the substations serving central Skopje.

EVN Macedonia’s new Centralna substation was developed to strengthen supply security, relieve existing capacity constraints and support the continued development of the city’s electricity infrastructure.

Located at a critical point in Skopje’s urban grid, the EUR 22 million facility has a reported installed capacity of 120 MW and incorporates 110 kV GIS equipment, a 24 kV double-busbar distribution system, remote-control infrastructure, cable monitoring, fire protection and advanced electronic protection and control systems.

For the medium-voltage distribution system, one of the key engineering requirements was clear: maintain operational flexibility and service continuity while enabling power distribution from two independent supply sources.

Solution: 54 Units of SNC Double Busbar Metal-Clad Switchgear

Aktif Elektroteknik supplied 54 units of 24 kV SNC Double Busbar Metal-Clad Switchgear for the Centralna substation.

The double-busbar architecture enables loads to be supplied through either of two independent busbars and allows controlled transfer between them.

This configuration helps the system maintain continuity when maintenance or a fault affects a busbar, transformer or circuit breaker by allowing relevant loads to be transferred to the alternative busbar.

The solution also supports:

• Load sharing between independent busbars
• Flexible switching and controlled load transfer
• Maintenance with reduced operational disruption
• Future feeder additions and system expansion
• Isolation of selected outgoing loads when required
• Greater operating flexibility in critical distribution centres

For a substation positioned at the centre of Skopje’s electricity network, this flexibility provides an important foundation for a more resilient distribution architecture.

Technical Solution: Designed for Continuity and Operational Safety

SNC Double Busbar combines a metal-enclosed, metal-partitioned and modular architecture with service continuity and personnel safety features required for demanding medium-voltage applications.

Key characteristics of the solution delivered for the project include:

• LSC-2B service continuity classification
• PM metallic partitioning
• AFLR internal arc classification
• IP4X external protection
• Mechanically and electrically interlocked switching architecture
• Segregated compartments for busbars, switching equipment, cables and low-voltage control systems
• Compliance with IEC 62271-200 and related international standards

The modular compartment structure provides organised and controlled access to circuit breaker, cable connection and control sections.

Internal arc pressure-relief arrangements are designed to direct pressure and gases away from personnel and adjacent equipment in the event of an internal fault, helping combine operational continuity, maintainability and safety within the same switchgear architecture.

Project Benefits

The SNC Double Busbar solution helps Centralna support:

1- Higher Service Continuity

Two independent busbars provide alternative supply paths and greater flexibility during maintenance or fault conditions.

2- Flexible Network Operation

Loads can be shared and transferred between busbars according to operational requirements.

3- Reduced Maintenance Disruption

The modular LSC-2B architecture supports maintenance activities while limiting their effect on other operational sections.

4- Future Expansion Capability

The modular system facilitates new feeder additions and future network expansion with reduced intervention.

5- Enhanced Operational Safety

Internal arc classification, metallic partitioning and mechanical/electrical interlocking support safer operation and maintenance.

6- Beyond Equipment Delivery

Aktif Elektroteknik remained actively involved throughout the commissioning and after-sales stages, supporting the integration of the supplied medium-voltage switchgear into the wider Centralna substation architecture.

This approach extends beyond equipment supply by bringing together engineering, manufacturing, testing, commissioning support and long-term technical collaboration.

7- Supporting a More Resilient Urban Grid

The commissioning of Centralna provides Skopje with a new strategic node for stable, secure and flexible electricity distribution.

For Aktif Elektroteknik, the project represents an important international reference for SNC Double Busbar technology in a high-capacity urban distribution application.

By combining two independent supply paths, modular switchgear architecture and proven safety classifications, the delivered solution supports a more resilient, adaptable and continuity-focused electricity network for the centre of Skopje.

Explore SNC Double Busbar Medium-Voltage Switchgear

Discover how double-busbar architecture can support service continuity, operational flexibility and safer maintenance in critical power distribution applications.