AN IMPROVED SANDIA FREQUENCY SHIFT METHOD FOR ISLANDING DETECTION OF GRID CONNECTED PHOTOVOLTAIC INVERTERS

Do Thanh Hieu; Nguyen Viet Ngu; Le Thi Minh Tam

Do Thanh Hieu Hung Yen University of Technology and Education
Nguyen Viet Ngu Hung Yen University of Technology and Education
Le Thi Minh Tam Hung Yen University of Technology and Education

Keywords: Islanding detection, Photovoltaic, Sandia Frequency Ship, Inverter

Abstract

Islanding detection schemes have been widely studied recently due to the expected high penetration of distributed generations (DGs) in future distribution networks. It is important for grid – connected inverter based DGs to be equipped with a reliable islanding detection method that allows efficient disconnection of DGs when an islanding condition is detected. In this paper, an improved Sandia Frequency Shift (SFS) method for islanding detection of grid connected photovoltaic (PV) inverters is proposed. The proposed technique through reducing chopping fraction cf0 and adjusting the feedback gain K increase exponentially to reduce the total harmonic distortion (THD) of the current waveform. To evaluate the performance
of the proposed technique, various islanding events have been implemented using a grid-connected PV system modeled in a Matlab/ Simulink, which are based on the IEEE 929-2000 and IEC 62116 standards. The simulation results show that the proposed method results in more accurate detection of the islanding phenomenon in the shortest possible time.

References

. A. Timbus, A. Oudalov, and C.N.M. Ho, “Islanding detection in smart grids,” in Proc. IEEE Energy Conversion Congress and Exposition, pp. 3631-3637, Sep. 2010.

. Ku Nurul Edhura Ku Ahmad, Jeyraj Selvaraj, and Nasrudin Abd Rahim, “A review of the islanding detection methods in grid-connected PV inverters,” Renewable and Sustainable Energy Reviews, vol. 21, pp. 756-766, May 2013.

. Ye. Zhihong, A. Kolwalkar, Y. Zhang, Du. Pengwei, and R. Walling, “Evaluation of anti-islanding schemes based on non-detection zone concept,” IEEE Trans. Power Electron., vol. 19, no. 5, pp. 1171-1176, Sep. 2004.

. L.A.C. Lopes and Zhang Yongzheng, “Islanding Detection Assessment of Multi-Inverter Systems With Active Frequency Drifting Methods,” IEEE Trans. Power Del., vol. 23, no. 1, pp. 480-486, Jan. 2008.

. H. Karimi, A. Yazdani and R. Iravani, “Negative-Sequence Current Injection for Fast Islanding Detection of a Distributed Resource Unit,” IEEE Trans. Power Electron, vol. 23, no. 1, pp. 298-307, Jan. 2008.

. L. A. C. Lopes and Huili Sun, “Performance assessment of active frequency drifting islanding detection methods,” IEEE Trans. on Energy Conversion, vol. 21, no. 1, pp. 171-180, March 2006.

. M. E. Ropp, M. Begovic, A. Rohatgi, G. A. Kern, R. H. Bonn and S. Gonzalez, “Determining the relative effectiveness of islanding detection methods using phase criteria and nondetection zones,” IEEE Trans. on Energy Conversion, vol. 15, no. 3, pp. 290-296, Sept. 2000.

. H. Vahedi, M. Karrari and G. B. Gharehpetian, “Accurate SFS Parameter Design Criterion for Inverter-Based Distributed Generation,” IEEE Trans. on Power Delivery, vol. 31, no. 3, pp. 1050- 1059, June 2016.