Modified Sandia voltage shift anti‐islanding scheme for distributed power generator systems

Abstract

This study presents an active anti‐islanding technique for distributed power generator systems. The proposed scheme is based on the Sandia voltage shift (SVS) technique, which is characterised by a small non‐detection zone (NDZ) and by an acceptable solution to the trade‐off between the output power quality and the effectiveness of islanding detection. The proposed technique has the advantage to improve the NDZ and to reduce the anti‐islanding detection times. This is due to the exponential‐product modification made in the positive feedback to inject current, thereby making the response faster than SVS. Additionally, a self‐adaptive gain is considered to achieve a low total harmonic distortion at different power levels. Moreover, the proposed scheme has been validated with theoretical and numerical analysis and experimental results. Finally, the behaviour and performance of the proposed technique are compared with other recent techniques.

Anti-Islanding Techniques for Integration of Inverter-Based Distributed Energy Resources to the Electric Power System

“…Nonetheless, SVS scheme performs slow islanding detection [139] and can also impact the inverter stability, due to the positive feedback of current. This problem can be mitigated by using an adaptive gain as in [140].…”

“…On the other hand, the main disadvantages of the SVS are the power quality degradation and the impacts on the inverter stability [63]. In order to diminishes the method drawbacks, [140] proposed a Modified Sandia Voltage Shift (MSVS) that uses an exponential adjustment in the gain of the voltage positive feedback. More than that, the method can be implemented in parallel with the SFS in order of improving the islanding diagnosis capability [141].…”

Enhancing grid resiliency in distributed energy systems through a comprehensive review and comparative analysis of islanding detection methods

“…Conversely, the primary drawbacks of the SVS are its effects on inverter stability and decrease PQ 131 . A MSVS that employs an exponential change in the gain of the voltage positive feedback was presented by 132 in an attempt to lessen the method's shortcomings. Furthermore, the technique can be used in tandem with the SFS to enhance the capacity to diagnose IS 133 .…”

A Novel Approach for Secure Hybrid Islanding Detection Considering the Dynamic Behavior of Power and Load in Electrical Distribution Networks

“…[56] To overcome the problems associated with remote IDMs, local IDMs are introduced, which are categorized into active and passive methods. There are several active IDMs proposed in the literature [19][20][21][22][23][24][25][26][27], which are shown in Table 1. Though for active IDMs, non-detection zones (NDZ) are very small, the power quality of the network is affected due to the injection of disturbance into the system, and their islanding detection speed is slower than passive IDMs [20,[22][23][24][25].…”

“…There are several active IDMs proposed in the literature [19][20][21][22][23][24][25][26][27], which are shown in Table 1. Though for active IDMs, non-detection zones (NDZ) are very small, the power quality of the network is affected due to the injection of disturbance into the system, and their islanding detection speed is slower than passive IDMs [20,[22][23][24][25]. On the other hand, passive IDM is one of the most cost-effective IDMs as the different operating parameters (power, frequency, voltage, current, harmonic distortion, etc.)…”