Planning a comprehensive protection scheme considering distributed generation

Various protection-factors arise due to the introduction of distributed generation, which can create problems in protecting the distribution system with distributed generators (DGs). Therefore, it is necessary to find out and analyze these protection-factors. This paper simulated a 25 KV sample distribution system in order to analyze and discuss these protection-factors, and also find out some new factors. This paper shows by using the simulated results that how a future protection scheme will be differed from the conventional one. Any protection scheme which is designed for overcoming one protection-factor may not be effective for another protection-factor. To resolve this, this paper gives a motivation for developing a comprehensive protection scheme which is capable of clearing the fault safely irrespective of the presence of any protection-factor. Moreover, this paper proposes a new formulation for determining the relays' coordination-settings which are able to protect the distribution system in the presence of most of the protection-factors. The performance of the proposed formulation is successfully tested on an 11kV, 5-feeders test distribution system.