A Hybrid Islanding Detection Method Based on the Rates of Changes in Voltage and Active Power for the Multi-Inverter Systems

This paper proposes a new hybrid islanding detection method for grid-connected photovoltaic system (GCPVS)-based microgrid. In the presented technique, the suspicious islanding event is initially recognized whilst the absolute deviation of the point of common coupling (PCC) voltage surpasses a threshold. After an intentional delay, a transient disturbance is injected into the voltage source inverter’s d-axis reference current to decline the active power output. As a result, the PCC voltage reduces in islanding operating mode whilst its variation is negligible in the grid presence. Therefore, the simultaneous drop of PCC voltage and active power output is used as an islanding detection criterion. The effectiveness of the proposed algorithm is investigated for various islanding and non-islanding scenarios for a practical distribution network with three GCPVSs. The simulation results in MATLAB/Simulink show successful islanding detection with a small non-detection zone within 300 ms without false tripping during non-islanding incidents. In addition to the precise and fast islanding classification, the presented scheme is realized inexpensively; its thresholds are determined self-standing, and its output power quality degradation is eminently small. Moreover, the active power output is restored to the nominal set after islanding recognition, enhancing the chance of GCPVS generation at its highest possible level in the autonomous microgrid.

Download Full-text

Development of Islanding Detection Based on Power Controlling for Grid-Connected of Dispersed Power Generation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.66 ◽

2011 ◽

Vol 383-390 ◽

pp. 66-71

Author(s):

Wei Min Chen ◽

Guo Cheng Chen ◽

Hui Cai

Keyword(s):

Power Generation ◽

Reactive Power ◽

Detection Method ◽

Active Power ◽

Islanding Detection ◽

Dispersed Generation

A novel islanding detection method based on Power Controlling is presented in this paper. The method continuously perturbs the reactive power supplied by dispersed generation systems while simultaneously monitoring the point of commoncoupling (PCC) voltage and frequency. When in grid-connected scenario, the voltage and frequency of PCC is insignificant; however, once the islanding event takes place, the frequency of PCC will be change own to the change of output reactive power. After it is over 4 cycles continuously, then the active power of dispersed generation systems is reduced to 80%, now a drop in voltage positively confirms islanding. Algorithm of the method is simple and confirmed by simulation with MATLAB.

Download Full-text

An Improved Islanding Detection Method for Photovoltaic Grid-Connected System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.748.453 ◽

2013 ◽

Vol 748 ◽

pp. 453-456

Author(s):

Chen Xin Li ◽

Qi Ping Yuan

Keyword(s):

Detection Method ◽

Harmonic Distortion ◽

Active Power ◽

Photovoltaic System ◽

Detection Methods ◽

Islanding Detection ◽

Detection Zone ◽

Frequency Detection ◽

Essential Function ◽

Maintenance Personnel

Islanding detection is a very essential function for a photovoltaic grid-connected system. Islanding phenomenons not only damage to equipment, but also endanger to the safety of the maintenance personnel. Passive islanding detection methods that use alone have considerable non-detection zone (NDZ); active islanding detection methods that use alone are that join disturbance to system, but the disturbance will cause system instability [1]. In this paper, an over/under voltage and over/under frequency detection method combines with an improved active power perturbation detection method are proposed. The photovoltaic system can be reduced non-detection zone (NDZ) with improved the power quality and reduced the total harmonic distortion (THD) through this method.

Download Full-text

A Hybrid Islanding Detection Method Considering Voltage Unbalance Factor

2020 IEEE International Symposium on Sustainable Energy, Signal Processing and Cyber Security (iSSSC) ◽

10.1109/isssc50941.2020.9358881 ◽

2020 ◽

Author(s):

Anwesha Manisha Nayak ◽

Mamun Mishra ◽

Bibhuti Bhusan Pati

Keyword(s):

Detection Method ◽

Islanding Detection ◽

Voltage Unbalance

Download Full-text

An Islanding Detection Method by Using Frequency Positive Feedback Based on FLL for Single-Phase Microgrid

IEEE Transactions on Smart Grid ◽

10.1109/tsg.2015.2508813 ◽

2017 ◽

Vol 8 (4) ◽

pp. 1821-1830 ◽

Cited By ~ 39

Author(s):

Qinfei Sun ◽

Josep M. Guerrero ◽

Tianjun Jing ◽

Juan C. Vasquez ◽

Rengang Yang

Keyword(s):

Positive Feedback ◽

Single Phase ◽

Detection Method ◽

Islanding Detection

Download Full-text

Over/Undervoltage and Undervoltage Shift of Hybrid Islanding Detection Method of Distributed Generation

The Scientific World JOURNAL ◽

10.1155/2015/654942 ◽

2015 ◽

Vol 2015 ◽

pp. 1-11 ◽

Cited By ~ 4

Author(s):

Manop Yingram ◽

Suttichai Premrudeepreechacharn

Keyword(s):

Control System ◽

Distributed Generation ◽

Hybrid Method ◽

Detection Method ◽

System Simulation ◽

Detection Methods ◽

Islanding Detection ◽

Active Method ◽

Passive Method ◽

Simulation Results

The mainly used local islanding detection methods may be classified as active and passive methods. Passive methods do not perturb the system but they have larger nondetection zones, whereas active methods have smaller nondetection zones but they perturb the system. In this paper, a new hybrid method is proposed to solve this problem. An over/undervoltage (passive method) has been used to initiate an undervoltage shift (active method), which changes the undervoltage shift of inverter, when the passive method cannot have a clear discrimination between islanding and other events in the system. Simulation results on MATLAB/SIMULINK show that over/undervoltage and undervoltage shifts of hybrid islanding detection method are very effective because they can determine anti-islanding condition very fast.ΔP/P>38.41% could determine anti-islanding condition within 0.04 s;ΔP/P<-24.39% could determine anti-islanding condition within 0.04 s;-24.39%≤ΔP/P≤ 38.41% could determine anti-islanding condition within 0.08 s. This method perturbed the system, only in the case of-24.39% ≤ΔP/P ≤38.41% at which the control system of inverter injected a signal of undervoltage shift as necessary to check if the occurrence condition was an islanding condition or not.

Download Full-text