A Current Limiting Reactor (CLR) is one of the most effective short circuit current limiting devices. It reduces stresses on busses, insulators, circuit breakers and other high voltage devices. Use of CLR is the most practical and economical approach at current limiting.
Current Limiting Reactors should be placed where the prospective short circuit current in a distribution or transmission system is calculated to exceed the interrupting rating of the associated switchgear. The inductive reactance is chosen to be low enough for an acceptable voltage drop during normal operation, but high enough to restrict a short circuit to the rating of the switchgear.
They are also used as load sharing reactors for balancing the current in parallel circuits. Current limiting reactors are manufactured up to 420 kV. These reactors are designed in a way to withstand the rated current continuously and fault currents for a certain period of time.
Inrush Current Limiting Reactors (Damping Reactors)
Inrush current limiting reactors are series connected with capacitors in order to limit the inrush currents that occur during their switching (switch-on) operations.
Advantages
- Increases equipment and capacitor life
- Perfect mechanical strength to withstand high short-circuit forces
- Limited temperature rise enables longer lifetime
- Special surface protection against UV, and for pollution Class IV areas
- Maintenance-free design
