Primary and backup protection in power system

Primary and Secondary or Backup protection in a very facility. Below is that the facility protection theme that is meant to shield the facility system components and elements. As shown in below fig, every line related to an overcurrent relay that defends the lines from faults.

Primary Protection 

Below is that the facility protection theme that is intended to guard the ability system components and parts. As shown in below fig, every line related to an overcurrent relay that protects the lines from faults. So, if a fault happens on any line, it’ll be cleared by its relay AND gate breaker. this is often known as primary or main protection and acts as a first-line defender. The service record of primary relaying is incredibly high with overrun ninetieth of all operations being correct. however this is often not perpetually the case, typically faults don’t seem to be light by the first or main protection system i.e. breaker and relay system owing to hassle inside the relays, circuit breakers or wiring system in numerous conditions. In those conditions, a Secondary or backup protection system will the specified job.

Secondary Protection

Back-up protection is incredibly vital for a stable and reliable installation
As we all know that, it’s impracticable to style a 100 percent secure and economical system as a result of there are prospects of failure within the connected CTs, PTs, electrical fuse, etc. within the system. If it happens, then it’ll destroy our whole change system.
If the first protection operation falls into bother, then secondary protection disconnects the faulty half from the system. Moreover, once we disconnect primary protection for testing or maintenance functions, then secondary or back-up protection can act as primary protection. within the higher than fig, relay “X” (1 Sec time setting) provides backup protection for every one of the four connected lines to the most bus.
In addition, a bigger half is disconnected than once primary relaying functions properly. Therefore, bigger stress ought to be placed on the higher maintenance of primary relaying that is economical.

Types of Secondary or backup protection

  • Relay Backup Protection
  • Remote Backup Protection
  • Breaker Backup Protection
  • Centrally Co-ordinate Backup Protection

Watch to Youtube Video