Maintaining overcurrent protection in a PV‐based distributed generation power systems.

Summary: The addition of photovoltaic (PV)‐based distributed generators introduces several challenges to power system protection and control engineers. In a multi‐source distribution network, power flow becomes bi‐directional, and conventional overcurrent and earth fault protection schemes are threatened. Addition of PV‐based distributed generation could lead to protection blinding, sympathetic tripping, and loss of coordination in conventional overcurrent protection. This paper evaluates the general concerns regarding protection in a PV‐based distributed generation network, by modeling a power system with sequence networks for different types of faults. The power system is simulated with Digsilent PowerFactory. The results show that many of the general concerns can be mitigated by using sequence components to identify faults. A method is presented to adapt conventional overcurrent protection schemes without the need for communication‐assisted protection. [ABSTRACT FROM AUTHOR]