I found this explanation on OEL limiters on Kundur Book using control blocks and a graph of field current versus time to explain the overall OEL mechanism. I have been trying to crack this explanation for days, yet I am still struggling. Can anyone explain this to me a little better and how these blocks are linked to make the UEL work as it is supposed to?Thank you in advance.

 

The Over Excitation Limiter (OEL) is designed to protect the field winding of a synchronous generator from excessive excitation current. This excess can lead to overheating and potential damage.