I am interested to know the latest trends adopted for distribution system protection. I would be very thankful to you for answering the following questions;
1) What are the modern trends used in various power distribution networks for protection?
2) How is protection coordination maintained in modern distribution systems in the presence of distributed generators?
3) Are the settings of relays kept fixed or changed as per prevailing power system conditions?
4) Does adaptive protection exist in the modern distribution systems?
Thank you so much for your contribution to this thread.
With best regards,
M. N. Alam
Your question is quite interesting, i will follow and expect other answers.
In general, what is desired in a protection system is that it is fast enough to identify abnormalities in the electrical system. What can be fast for one may not be for others, so the mechanical elements are still quite widespread in power plants.
Basically, the operating principle of the current protections are similar to the old ones. What changes is the computational aspect inserted with the "Modernization" of electrical systems. Thus, we have measured several locations and control the system. This makes above price and sometimes does not compensate for switching a mechanical relay to a digital one.
In large hydropower plants complex (~4.000 MW)there is still use of mechanical relays due to its reliability and use over the years, I have seen systems over 30 years old that normally operate in the region of Paulo Afonso, Bahia, Brazil.
SCADA (Supervisory Control and Data Acquisition) is being used in Distribution Automation using lot of sensors, which takes care of the protection also.
I guess I have few pointers and whom to listen to:
Ratan Das:https://www.researchgate.net/profile/Ratan_Das3
http://www.epcc-workshop.net/archive/2013/assets/downloads/das-presentation-protection-and-automation.pdf
Paul Mydra:
https://www.naspi.org/sites/default/files/2017-03/git_meliopoulos_sychrophasor_technology_20160322.pdf
Hope this helps!