The 35kV busbar is a double busbar

A 35 kV double busbar system uses two main buses in parallel, allowing circuits to connect to either bus for enhanced reliability, flexibility, and maintenance capability.

Overview of 35 kV Busbars

A 35 kV busbar is a critical node in medium-voltage power systems, serving as a hub for collecting and distributing electrical energy between generators, transformers, and outgoing feeders. It can be constructed using tubular busbars for compactness, ease of installation, and maintenance, and is often equipped with arc flash protection to quickly clear faults . In substations, the busbar layout determines operational flexibility, fault isolation, and continuity of service.

Double Busbar Configuration

In a double busbar system, two main buses run in parallel, and each circuit can connect to either bus through dedicated circuit breakers. This arrangement is often referred to as a double breaker/double bus (DB/DB) scheme . Key features include:

• Redundancy: If one bus experiences a fault, circuits can continue operating via the other bus, minimizing downtime .
• Maintenance Flexibility: Circuits can be switched between buses, allowing maintenance on one bus without interrupting power supply .
• Operational Flexibility: Circuits can be connected to both buses simultaneously or assigned to a specific bus, depending on operational needs .
• Fault Management: Only the breaker leading to the faulty bus trips, leaving other circuits energized through the healthy bus .

Advantages Over Single Busbar

Compared to a single busbar, a double busbar system provides:

• Higher Reliability: Continuous power supply is maintained even during bus faults .
• Improved Load Transfer: Circuits can be moved between buses without shutdown, supporting critical facilities like data centers, hospitals, or large industrial plants .
• Enhanced Maintenance Access: Planned work can proceed without a total substation shutdown .
• Better Fault Isolation: Faults on one bus do not affect the entire system .

Considerations

While double busbar systems offer superior reliability and flexibility, they require:

• Higher Cost: More equipment, including additional busbars, breakers, and couplers .
• Larger Footprint: More space is needed to accommodate the two buses and associated components .
• Complex Control: Skilled operation and coordination are necessary to manage switching and protection schemes . In summary, a 35 kV double busbar system is ideal for substations where continuous power, operational flexibility, and fault resilience are critical. It allows circuits to remain energized during maintenance or bus faults, providing a robust solution for medium-voltage power distribution .