Feeder, Busbar, & Transformer Protection

Objectives
• Understand the principles, application, and settings of feeder protection.
• Learn the critical role and complexity of busbar protection (High Impedance, Low Impedance).
• Review transformer protection schemes, including differential, restricted earth fault, and over fluxing.

Key Topics
• Feeder Protection: Overcurrent (50/51), Directional Overcurrent (67), Distance Protection (21).
• Busbar Protection: Need for high-speed clearance, CT saturation issues, check zones, and supervision.
• Transformer Protection: Differential (87T), Restricted Earth Fault (64REF), Overcurrent (50/51), Buchholz, Winding Temperature.
• Auto-Reclosing: Philosophy for overhead lines.

Practical Focus
• Interpreting a transformer differential protection characteristic curve.
• Case study: Analyzing a mal-operation of a busbar protection scheme.

Suggested Diagrams
• Schematic of a busbar protection zone for a double-busbar arrangement.
• Biased differential characteristic curve for a transformer protection relay.

Key Takeaways
• Comprehensive knowledge of main protection schemes for substation assets.
• Ability to review protection settings and SLDs for these schemes.

Standards & References
• IEEE C37.91 – Guide for Protecting Power Transformers.
• IEEE C37.97 – Guide for Protective Relay Applications to Power System Buses.
• IEC 60255-121 (Distance), -127 (Overcurrent), -118-1 (Differential).

Certification & Delivery
• Certificate of Completion awarded.
• Delivery Mode: Online (On-demand).
• Corporate and customized training available on request.