Augmenting Feeder Protection Dependability under High Penetration of DERs

Distributed Energy Resources (DERs) have emerged as prevalent players in the energy market, driven by government subsidies, carbon tax adoption, environmental concerns, and potential utility infrastructure investment deferrals. Often, utilities must deal with technical issues arising from paradigm shifts such as large-scale adoption of DERs. One of these technical challenges is the degradation of dependability of feeder protection, which results from the short-circuit contribution from DERs connected to distribution lines. This additional fault infeed can desensitize feeder relays and slow down overcurrent elements. This paper presents measures to address this issue and quantifies their effectiveness.