Hybrid islanding detection technique for single‐phase grid‐connected photovoltaic multi‐inverter systems

Abstract

This study presents the performance of a novel hybrid islanding detection method for multi‐single‐phase photovoltaic (PV) inverters based on the combination of four active methods and three passive methods. Although islanding detection in PV multi‐inverter systems has been widely researched, most islanding studies are focused on three‐phase inverters, rather than single‐phase ones. In this study, different active and passive methods are used to detect the islanding of four paralleled single‐phase PV inverters. By combining those methods synergistically, it reduces their weakness of each method, while combining their advantages. The novelty of the proposed system methodology consists of four paralleled single‐phase inverters equipped with four different active methods, namely active frequency drift, Sandia frequency shift (SFS), sliding mode frequency shift, and Sandia voltage shift triggered by a block composed of three passive methods: voltage frequency protection, rate of change of frequency, and DC‐link. This novel hybrid system is studied under different detailed scenarios, where it shows its performance and characteristics.

Review on islanding detection methods for grid‐connected photovoltaic systems, existing limitations and future insights

“…The combination of four active and three passive IDMs has been developed by Barkat et al. [59]. This IDM identifies numerous islanding scenarios in a single‐phase GCPVS system within 148 ms without any false tripping during non‐islanding cases.…”

Review, analysis, and performance evaluation of the most common four active methods for islanding detection in grid-connected photovoltaic systems

“…This paper explores the islanding performance of the most used four active IDMs for single-phase grid-connected photovoltaic (PV) systems, as indicated in [34]. Although the unintentional islanding of PV systems has been deeply investigated in the last decade, it is still a timely subject, as new requirements have arisen, such as the performance of these methods under fault-ride through (FRT) required by grid codes.…”

“…The main disadvantage of the passive anti-islanding strategies is that they have a larger non-detection zone (NDZ) [27], [29]- [33]. Many active anti-islanding methods have been elaborated to avoid this drawback [32], [34]. The active methods [35], [36] generate some perturbations at the point of common coupling (PCC) of the PV system [27], [29], [37] to change one or more power grid parameters that can be sensed by the passive IDMs [5], [22]; thus, minimize the so-called NDZ [29], [37], [38].…”

Hybrid islanding detection technique for distribution network considering the dynamic behavior of power and load

“…The RLC load's amplitude and phase angle are given by Equations ( 11) and (12). The resonant frequency f 0 and quality factor Q f are given by Equations ( 13) and (14).…”

“…There are several active IDMs that are proposed in literature such as reactive power export error detection method, 11 active frequency drift (AFD), 12 impedance measurement method, 13 active frequency drift with positive feedback (AFDPF), 14 and so forth. For the implementation of active IDMs, a small disturbance is injected into the network to monitor the parameters of distribution network.…”