Transient regimes in electrical systems are momentary, temporary changes in voltage and current caused by events like switching, faults, or lightning strikes. These disturbances can disrupt a circuit's steady-state operation, causing damage to equipment or malfunctions before the system returns to its normal operating conditions. They are categorized as either impulsive (single direction) or oscillatory (changing polarity) and require protection from events that cause them.
Causes:
Switching operations: Closing or opening switches, circuit breakers, and connecting/disconnecting loads are common internal sources.
External events: Lightning strikes and electrostatic discharge are major external causes.
Equipment-related issues: Internal components like transformers and motors, as well as power electronic operations, can generate them.
Other causes: Faults, resonance, and power system energizing can also trigger transients.
- Enseignant: HAKIM AIT SAID