Why Protection System is Needed in Power System

by Jaspreet Singh Digital Marketing Expert

The main aim of power system protection is to find a faulty section in power system in order for rest portion of the system to function smoothly without any damage due to fault current.

We use circuit breakers tat isolates the faulty part from the rest and these circuits automatically open during fault condition with trip signal that comes from protection relay. We build short circuit path in the system which results in the discontinuation of the current flow because of the fault leakage. It is the protection from fault current in protection system rather than protecting the system itself. The protection relay must have following functional requirements:

Reliability

The reliable protection relay is the most important functionality. As they remain inactive for a long duration of time; they must act when needed, If fault occurs.

Selectivity

The protection relay must operate in the scenario for which they are designed to operate. In some cases the fault demands definite time delay so the protection relay must act accordingly. Hence protection relay must be sufficiently capable to select appropriate condition for which it would be operated.

Sensitivity

The electrical equipment used for protection relays must be sensitive to the fault condition so that it can smoothly cast out the limit needed for smoother functioning of the rest of the power system.

Speed

The speed of the protective relays must operate at the defined speed limit. It must coordinate the speed according to the current speed that is flowing through the healthy portion of the circuit as well as the speed of the current that is flowing in faulty section of the circuit. It should neither be too slow which may result in damage to the equipment nor should it be too fast which may result in undesired operation.

The electrical instruments used to protect power system must be of high quality. So getting the products from right electrical equipment suppliers is must.