PROJECT TITLE :

An Islanding Detection Method for Inverter-based Distributed Generators

ABSTRACT:

For inverter-based distributed generators (DG), an islanding detection method based on perturbing reactive power output is provided in this study. This approach employs two distinct sets of disturbances, each with a unique amplitude and duration. FSOPD and SSOPD are two sets of reactive power disturbances, the first set of which is periodic and small enough to disrupt the reactive power balance during islanding; while SSOPD is large enough to cause the frequency to diverge from its threshold limits. When the FSORPD is islanded, there are three criteria for switching the disturbance to the SSORPD, based on all conceivable frequency variation features. The SSORPDs can be introduced to several DGs at the same time without the need for communication because the DGs share the same frequency variation characteristics. When there are several generators, the SSORPD approach can identify islanding since there is no nondetection zone for islanding. If the DG is operating at unity power factor, this method can also be used to provide the local load with reactive energy. Many case studies in power systems computer-aided design/Electro magnetic transient in DC system environments have demonstrated the efficiency of the antiislanding test system proposed by IEEE Std.929-2000 and IEEE Std.1547-2003.