The effect of different control modes and mixed types of DG on the non-detection zones of islanding detection

Abstract

Loss of mains protection (LOM) is among the most challenging issues related to the integration of distributed generation (DG). This paper presents simulation studies on the effect of multiple DG units on LOM protection. The results reveal an operational risk related to the active LOM detection methods. The effect of voltage droop control of the DG on the form of the NDZ is also studied.

Bayesian Entropy Methodology: A Novel Approach to Setting Anti-Islanding Protections with Enhanced Stability and Sensibility

“…While this approach could avoid the need for complex processing techniques, in this work the thresholds were arbitrarily chosen with no certainty of their optimality. Moreover, the method was only tested for protecting photovoltaic systems, and the selected thresholds may not be suitable when synchronous or asynchronous machines are present in the formed island, as they can change the dynamics of the electrical variables and the NDZ [46].…”

Network information system based loss of mains risk management

“…Moreover, a converter coupled DG unit behaves very differently than a directly coupled generating unit. [4] - [6] The estimation of the NDZ regions is a laborious task but it is, nonetheless, doable. This task could be done within a reasonable time frame by using a real time simulator as presented in [4].…”

“…[4] - [6] The estimation of the NDZ regions is a laborious task but it is, nonetheless, doable. This task could be done within a reasonable time frame by using a real time simulator as presented in [4]. The difficult task in such estimation is choosing an appropriate simulation model.…”

“…The modeling of the DG unit(s) is naturally an essential issue for obtaining realistic NDZ estimates. The simulation model should probably include a converter coupled DG and a directly coupled synchronous generator in parallel since the relationship between active-and reactive power with voltage magnitude and frequency is different for directly connected and converter connected DG units [4]. The exciter of the synchronous generator should be set to control the terminal voltage [5].…”

Performance analysis of Q-f droop anti-islanding protection in the presence of mixed types of DG

“…The behavior of an islanded circuit sustained by only inverters is significantly different in comparison with the behavior of an islanded circuit sustained by SG only. That is, the time constants related to SG sustained circuits are greater than inverter sustained circuits and the relation between active-and reactive power with voltage magnitude and frequency are different [6]. This fact may cause the active methods designed for inverter based DG units to fail to detect islanding in case if the islanded circuit contains both SG and inverter based DG.…”