High-Current Generator Circuit Breakers for Power Plant

Based on a modern GCB platform with short-circuit ratings of 130 kA and continuous current ratings of 17,500 A, the system satisfies the demanding requirements of the largest pumped storage power plants worldwide. The complete assembly — including circuit-breaker, disconnector, capacitors, and control cubicle — is delivered fully assembled to reduce installation and commissioning time. Earthing switches, current and voltage transformers, and surge arresters can be integrated as additional components. All control, monitoring, and interlocking functions are managed from a single control cubicle. 

Key Features

• Integrated multi-function system： Combines GCB, five-phase disconnector with phase reversal, and braking switch in one coordinated assembly from a single manufacturer
• SFC and BTB starting capability：Built-in starting switches for static frequency converter and back-to-back starting modes common in pumped storage plants
• Five-phase disconnector with phase reversal： Enables generator/motor mode switching by reversing phase sequence
• High continuous and short-circuit ratings： Suitable for the largest pumped storage units at 25.3 kV class
• Factory-assembled and tested： Pre-assembled system minimises site installation, wiring, and commissioning effort
• Single control cubicle：Centralised control, monitoring, and interlocking across all system modules
• Modular expandability ： Optional integration of earthing switches, CTs, VTs, and surge arresters

Technical Parameters

System Modules

• Generator main circuit protection, control, and phase reversal in pumped storage hydropower plants
• High-capacity pumped storage units requiring SFC and BTB starting methods
• Integration of generator circuit-breaking, disconnecting, phase reversal, and braking functions in a single system
• New power plant installations and major upgrades requiring coordinated multi-function switchgear

Custom ratings (voltage, current, breaking capacity) and additional components (earthing switches, CTs, VTs, surge arresters) available on request. Contact Rockwill for application-specific design and quotation.