Protection equipment in power system

What is power system protection?

The core idea of power system protection is not to stop fault current but to quickly disconnect the fault path to prevent further damage. This quick action is critical and relies on the functional requirements of protection relays. Let’s have a discussion on basic concept of protection system in power system and coordination of protection relays.

What devices are used to protect power systems from faults?

The devices that are used to protect the power systems from faults are called protection devices. Protection systems usually comprise five components Communication channels to allow analysis of current and voltage at remote terminals of a line and to allow remote tripping of equipment.

What is a power system protection scheme?

The objective of a protection scheme is to keep the power system stable by isolating only the components that are under fault, whilst leaving as much of the network as possible in operation. The devices that are used to protect the power systems from faults are called protection devices. Protection systems usually comprise five components

Why is protection important in power system design?

The provision of adequate protection to detect and disconnect elements of the power system in the event of fault is therefore an integral part of power system design. Only by so doing can the objectives of the power system be met and the investment protected.

What is a power system protection relay?

Consists of mainly power system protection relays like current relays, voltage relays, impedance relays, power relays, frequency relays, etc. based on operating parameter, definite time relays, inverse time relays, stepped relays etc. as per operating characteristic, logic wise such as differential relays, over fluxing relays etc.

How do you protect a power system if a fault occurs?

To limit the extent of the power system that is disconnected when a fault occurs, protection is arranged in zones. The principle is shown in Figure A1.5. Ideally, the zones of protection should overlap, so that no part of the power system is left unprotected. This is shown in Figure A1.6(a), the circuit breaker being included in both zones.