Circuit breaker protection schemes for substation

A crucial topic in electrical engineering!

Circuit breaker protection schemes are essential in substations to ensure the safe and reliable operation of the electrical grid. Here are some common circuit breaker protection schemes used in substations:

  1. Overcurrent Protection: This scheme is designed to protect the circuit from excessive currents that can cause damage to the equipment or start a fault. The circuit breaker trips when the current exceeds a predetermined value.
  2. Overvoltage Protection: This scheme is designed to protect the circuit from excessive voltages that can cause damage to the equipment or start a fault. The circuit breaker trips when the voltage exceeds a predetermined value.
  3. Undervoltage Protection: This scheme is designed to protect the circuit from low voltages that can cause equipment malfunction or failure. The circuit breaker trips when the voltage falls below a predetermined value.
  4. Earth Fault Protection: This scheme is designed to detect and trip the circuit breaker in the event of an earth fault (ground fault) in the circuit. This is typically achieved using earth fault relays.
  5. Phase Fault Protection: This scheme is designed to detect and trip the circuit breaker in the event of a phase-to-phase fault (short circuit) in the circuit.
  6. Ground Fault Protection with Neutral Grounding: This scheme is designed to detect and trip the circuit breaker in the event of a ground fault in the circuit, while also providing a path for fault current to flow to ground through the neutral grounding transformer.
  7. Distance Protection: This scheme is designed to detect and trip the circuit breaker in the event of a fault in the circuit, based on the distance from the fault to the circuit breaker. This is typically achieved using distance relays.
  8. Impedance Protection: This scheme is designed to detect and trip the circuit breaker in the event of a fault in the circuit, based on the impedance of the circuit. This is typically achieved using impedance relays.
  9. Synchronism Check: This scheme is designed to ensure that the circuit breaker trips only when the fault is synchronized with the system voltage. This is typically achieved using synchronism check relays.
  10. Backup Protection: This scheme is designed to provide backup protection in the event of a primary protection failure. This is typically achieved using backup relays.

Some common circuit breaker protection schemes used in substations include:

  1. ANSI (American National Standards Institute) 37: This scheme is widely used in North America and is based on the ANSI C37.2 standard.
  2. IEC (International Electrotechnical Commission) 60255: This scheme is widely used in Europe and is based on the IEC 60255 standard.
  3. ABB (Asea Brown Boveri) Protection Scheme: This scheme is widely used in Europe and is based on the ABB protection scheme.
  4. Siemens Protection Scheme: This scheme is widely used in Europe and is based on the Siemens protection scheme.

These are just a few examples of the many circuit breaker protection schemes used in substations. The choice of protection scheme depends on the specific requirements of the substation and the electrical grid it serves.