A hybrid islanding detection technique for inverter‐based distributed generator units

Abstract

Summary Due to high importance of islanding detection as an essential protection requirement, especially for the distributed generation (DG), a new approach to islanding detection is developed in the present paper. The method is based on a mixture of both active and passive algorithms, which uses voltage phase angle (VPA) and voltage unbalance (VU). The suggested method presents a combination of benefits of each individual passive/active method, and therefore it is useful to appropriately detect islanding situation in a wide range of scenarios. The use of the suggested method results in smaller nondetection zone (NDZ), faster response, and improved power quality. In order to illustrate the effectiveness of this approach, simulation results are provided under different conditions, showing that the suggested algorithm can reach the required islanding protection requirements. In addition, the performance of the proposed method and some other methods are compared by the presence of a variety of transient faults and insignificant power mismatch.

Data Description Technique-Based Islanding Classification for Single-Phase Grid-Connected Photovoltaic System

“…Therefore, from the above Equations (16) and (17), it is evident that by minimizing the Euclidean norm, an optimal separating hyperplane can be achieved, as follows:…”

“…It does present a small NDZ, but the introduction of perturbance in the system may lead to the degradation of power quality, and if it is significant, it may make the system unstable even when the system is not islanded [16]. To overcome the drawback of both the active and passive islanding technique, the hybrid islanding technique [17] was introduced, in which the perturbation is injected when abnormality is detected in the system, and as a result, the NDZ is small. However, the islanding detection time is prolonged, as both the detection methods are implemented.…”

A new time domain passive islanding detection algorithm for hybrid distributed generation systems

“…Later, hybrid islanding detection methods were proposed by integrating active and passive approaches to experience the benefits of either of the techniques, but the drawback is developing such an effective control strategy is more complicated. 16 Usually, time-domain analysis is used to detect islanding in passive techniques. However, frequency-domain techniques such as s-transform 17 and Wavelet Transform 18 have also been presented in the literature.…”

“…The islanding might be observed incorrectly in many above mentioned passive and active techniques owing to power disturbances triggered by certain conditions like load switching, capacitor switching, and short‐circuit faults, etc. Later, hybrid islanding detection methods were proposed by integrating active and passive approaches to experience the benefits of either of the techniques, but the drawback is developing such an effective control strategy is more complicated 16 . Usually, time‐domain analysis is used to detect islanding in passive techniques.…”

Selecting and sizing transformer and AC cable for PV system's safe and reliable operation

“…Fault detection techniques are reported by the previous works. [3][4][5][6][7][12][13][14]16,[24][25][26][27][28][29][30] But other works 3-5,7,12-14 have limited fault detection to DC (PV) side without referencing AC side. On the other hand, previous studies 6,16,24-26 discuss AC (utility) side islanding detection and have proposed multitude of passive islanding detection techniques relying on the detection of V and/or f abnormality at the PCC.…”