In order to ensure the safe operation of the power supp […]
In order to ensure the safe operation of the power supply and distribution system and avoid the impact of overcurrent caused by overload and short circuit on the system, different types of overcurrent protection devices should be installed in the power supply and distribution system. Commonly used overcurrent protection devices include fuse protection, low-voltage circuit breaker protection and relay protection. Among them, relay protection is widely used in high-voltage power supply and distribution systems. It has many protection functions and is the basis for realizing power supply and distribution automation.
(1) Automatically, quickly and selectively remove faulty components from the power supply and distribution system, so that other non-faulty parts can quickly resume normal power supply;
(2) It can correctly reflect the abnormal operation status of electrical equipment and send out a forecast signal so that the operator can take measures to restore the normal operation of electrical equipment;
(3) Cooperate with the automatic devices of the power supply and distribution system (such as automatic reclosing devices, automatic backup power input devices, etc.) to improve the operational reliability of the power supply system.
The relay protection of the building power supply and distribution system is simple, effective, reliable, and has strong anti-interference ability.
2. Basic requirements for relay protection
The design of relay protection should be based on reasonable operation mode and possible fault types, and should meet the four basic requirements of selectivity, quick action, reliability and sensitivity.