Introduction
Protection and control systems are essential for the safe operation of modern substations.
Electrical networks can experience faults such as short circuits, equipment failures, abnormal voltage conditions, and other disturbances. Protection systems are designed to detect defined abnormal conditions and initiate appropriate actions.
What Is a Protection System?
A protection system consists of equipment and logic used to detect abnormal electrical conditions and isolate affected sections when required.
Common elements include:
- Protection relays
- CTs
- VTs/PTs
- Circuit breakers
- Trip circuits
- DC systems
- Control panels
Role of Protection Relays
Protection relays continuously receive electrical information from instrument transformers and evaluate it against configured protection criteria.
When the applicable protection condition is detected, the relay can send a trip command to the relevant circuit breaker.
Control Systems
Control systems allow operators to monitor and control substation equipment.
They can include:
- Control panels
- Indication systems
- Alarm systems
- Local controls
- Remote controls
- Monitoring systems