How not to nuisance-trip distributed generation

This paper provides insight on how to prevent nuisance-trips from occurring on distributed generation (DG). The protection system at the DG interconnection must provide security to allow the DG to be connected to the utility grid, as well as reliably disconnect the DG from the utility grid for a variety of reasons. Most protection systems are set to trip the DG offline in less than one second, and often much quicker (10-30 cycles). Events can occur on the system and within the DG Facility, however, that may lead to undesired trips. These trips occur due to protection elements being set with very close tolerances and the interplay of events that include power surges from cycling of loads within a DG facility, faults within the DG facility that should be cleared by other means, and misapplication of protective elements. Various scenarios that can lead to nuisance tripping of DGs are discussed as well as a feature of modern protective systems that is an event analysis aid, waveform capture, applied at the point of common coupling at the DG facility and the utility