ABB grid circuit breaker unit GBU72

ABB grid circuit breaker unit GBU72 is a core protection and control device designed by ABB for medium and high voltage power grids (such as 10kV-35kV). It is mainly used for fault isolation, load switching and grid stability maintenance of power systems.

Core functions and technical characteristics

1. Mechanical and electrical performance

Rated parameters:

Rated voltage: 12kV/24kV/36kV (depending on the model version).

Rated current: 630A-4000A (expandable to 6300A).

Short-circuit breaking capacity: 40kA-63kA (in accordance with IEC 62271-100 standard).

Operating mechanism:

Spring energy storage mechanism: supports manual/electric energy storage, and the opening and closing time is ≤50ms (typical value).

Permanent magnet mechanism (optional): no mechanical wear, life of more than 100,000 times, suitable for frequent operation scenarios.

Insulation design:

Vacuum interrupter: CuCr contact material, arc erosion resistant, life ≥ 30,000 times. ABB DO910B Digital Output Module for Automation Control Systems

Composite insulation (optional): epoxy resin + silicone rubber sleeve, suitable for highly polluted environments (such as salt spray, chemical industry zone).

. Protection and control functions

Built-in protection device:

Overcurrent protection: quick break, time limit/inverse time limit overcurrent protection, action time ≤ 20ms.

Zero sequence protection: detect ground fault, adjustable sensitivity (0.1A-10A).

Reclosing function: support primary/secondary reclosing, interval time can be set (0.5s-10s).

Intelligent control:

IEC 61850 communication: support GOOSE/SV message transmission, realize seamless connection with smart substation.

Synchronous closing: through PTP time synchronization (accuracy ≤ 1μs), reduce the closing impact current.

Partial discharge monitoring: built-in ultrasonic/UHF sensor, real-time monitoring of insulation status.

Environmental adaptability

Protection level: IP4X (cabinet)/IP65 (circuit breaker body), dustproof and waterproof.

Working temperature: -25℃~+55℃ (extended range requires special design), adaptable to high altitude (reduced capacity is required above 4000m).

Seismic design: in accordance with IEC 60068-2-6 standard, seismic level 8 (suitable for earthquake-prone areas). ABB PU515A 3BSE032401R1 Industrial Automation Module

Typical application scenarios

Power plant

As a generator output circuit breaker (GCB), it realizes flexible connection between the generator and the power grid, and supports black start and island operation.

Cooperate with the plant power switching device to ensure continuous power supply of important loads (such as boiler feed water pumps).

Substation

Medium voltage incoming line/feeder protection, quickly isolate the fault line, and reduce the scope of power outage.

Cooperate with the busbar section circuit breaker to realize grid partition operation and load balancing.

Industrial power distribution system

In continuous production industries such as steel and chemical industry, short-circuit current is used to prevent equipment from being damaged (such as arc furnaces and compressors).

Power supply for key loads such as data centers and hospitals supports automatic switching of dual power sources (ATS).

Grid connection of new energy

Protection of photovoltaic power stations and wind farms to adapt to the intermittent characteristics of distributed power sources.

Charge and discharge control of energy storage system to achieve peak-valley arbitrage and demand response.

Maintenance and troubleshooting

1. Daily inspection

Confirm that the position of the circuit breaker opening and closing indicator is correct and the energy storage indicator is on.

Check the oil level of the operating mechanism (hydraulic mechanism) or the energy storage status of the spring (spring mechanism).

Listen to the operating sound. Abnormal noise may indicate wear of the arc extinguishing chamber or contacts.

2. Regular maintenance

Every 6 months:

Clean the circuit breaker housing and insulators and check the tightness of the terminal block.

Measure the main circuit resistance (≤50μΩ, in accordance with IEC 60694 standard).

Every year:

Conduct mechanical property test (opening and closing time, speed, synchronization).

Check protection setting (such as overcurrent, zero-sequence protection action value).

3. Common fault handling

Unable to close:

Check whether the control power supply (DC220V/AC110V) is normal.

Confirm that the energy storage mechanism has stored energy (spring mechanism) or the permanent magnet mechanism coil is energized. ABB DO910B Digital Output Module for Automation Control Systems