Institucional Revista Notícias Contato Acesso Associado

Revista Eletrônica de Potência (Brazilian Journal of Power Electronics)

Issue: Volume 24 - number 3
Publishing Date: setembro 2019
Editor-in-Chief: Marcello Mezaroba
Editor Affiliation: Universidade do Estado de Santa Catarina - UDESC
Lucas Vizzotto Bellinaso, Ricardo S. Figueredo, Marcelo P. Almeida, Ricardo J. F. Bortolini, Leandro Michels, Ildo Bet, Roberto Zilles
English Data


Keywords: Electric shock, Photovoltaic power systems, Power Electronics, Protective relaying, Uninterruptible Power Systems


Grid-connected photovoltaic systems with energy storage, also called PV hybrid mini-grid system (PVHMS), operate in both grid-tied and stand-alone modes and are expected to play an important role in distributed generation. Transformerless photovoltaic converters are most preferred for these systems due to their higher conversion efficiency in comparison to insulated converters, increasing autonomy of the battery energy storage system (BESS). Safety in transformerless photovoltaic converters is a critical issue due to parasitic capacitance between PV modules and ground that could result in high leakage current. Existing safety requirements for grid-tied PV inverters may not be sufficient for PVHMS converters since they have multiple leakage current paths. This study analyzes some leakage-current-related faults on transformerless PVHMS converters, and proposes relay opening sequences to avoid unnecessary interruptions of power supply for the local loads. The following situations are analyzed: i) fault at dc side, ii) fault at ac load side, and iii) commutation between on-grid and off-grid operation modes. These faults have been studied for a transformerless PVHMS converter with a single dc-ac stage. Experimental results are presented to validate the proposed schemes and a table summarizing the proposals is presented.


[1] G. Léna, Rural Electrification with PV Hybrid Systems. 2013.
[2] J. Hazelton, A. Bruce, and I. MacGill, “A review of the potential benefits and risks of photovoltaic hybrid mini-grid systems,” Renew. Energy, vol. 67, pp. 222–229, 2014.
[3] F. Harirchi, M. G. Simoes, M. Babakmehr, A. AlDurra, S. M. Muyeen, and A. Bubshait, “Multi-functional double mode inverter for power quality enhancement in smart-grid applications,” in 2016 IEEE Industry Applications Society Annual Meeting, 2016, pp. 1–8.
[4] E. Ozdemir and F. Kavaslar, “A new multifunctional power converter for grid connected residential photovoltaic applications,” in 2009 IEEE Energy Conversion Congress and Exposition, 2009, pp. 2650–2656.
[5] N. Sasidharan and J. G. Singh, “A Novel Single-Stage Single-Phase Reconfigurable Inverter Topology for a Solar Powered Hybrid AC/DC Home,” IEEE Trans. Ind. Electron., vol. 64, no. 4, pp. 2820–2828, Apr. 2017.
[6] P. V. Subramanyam and C. Vyjayanthi, “Integration of PV and battery system to the grid with power quality improvement features using bidirectional AC-DC converter,” in 2016 International Conference on Electrical Power and Energy Systems (ICEPES), 2016, no. Cv, pp. 127–132.
[7] L. Bellinaso and L. Michels, “Multifunctional Photovoltaic Converters – Classification And Requirements For Grid And Load Compatibility,” Eletrônica de Potência, vol. 21, no. 2, pp. 126–137, May 2016.
[8] R. J. F. Bortolini, L. Michels, L. V. Belinaso, and J. R. Massing, “Compatibilizing multifunctional photovoltaic converters with Brazilian standards: Analysis and discussion,” 14th Brazilian Power Electron. Conf. COBEP 2017, vol. 2018–January, pp. 1–6, 2018.
[9] Y. Tang, W. Yao, P. C. Loh, and F. Blaabjerg, “Highly Reliable Transformerless Photovoltaic Inverters with Leakage Current and Pulsating Power Elimination,” IEEE Trans. Ind. Electron., vol. 63, no. 2, pp. 1016–1026, 2016.
[10] S. Karve, “Three of a kind,” IEEE Rev., no. March, pp. 27–32, 2000.
[11] C. A. Charalambous, A. Demetriou, and N. D. Kokkinos, “Impact of Photovoltaic-Oriented DC Stray Current Corrosion on Large-Scale Solar Farms’ Grounding and Third-Party Infrastructure: Modeling and Assessment,” IEEE Trans. Ind. Appl., vol. 51, no. 6, pp. 5421–5430, Nov. 2015.
[12] B. Gu, J. Dominic, J. S. Lai, C. L. Chen, T. Labella, and B. Chen, “High reliability and efficiency single-phase transformerless inverter for grid-connected photovoltaic systems,” IEEE Trans. Power Electron., vol. 28, no. 5, pp. 2235–2245, 2013.
[13] T. Kerekes, D. Sera, and L. Mathe, “Leakage current measurement in transformerless PV inverters,” Proc. Int. Conf. Optim. Electr. Electron. Equipment, OPTIM, pp. 887–892, 2012.
[14] J. M. A. Myrzik and M. Calais, “String and module integrated inverters for single-phase grid connected photovoltaic systems – A review,” 2003 IEEE Bol. PowerTech – Conf. Proc., vol. 2, pp. 430–437, 2003.
[15] SMA, “Technical Information Capacitive Leakage Currents,” 2015.
[16] M. Calais, V. G. Agelidis, and M. Meinhardt, “Multilevel converters for single-phase grid connected photovoltaic systems: an overview,” Sol. Energy, vol. 66, no. 5, pp. 325–335, Aug. 1999.
[17] W. Li, Y. Gu, H. Luo, W. Cui, X. He, and C. Xia, “Topology review and derivation methodology of single-phase transformerless photovoltaic inverters for leakage current suppression,” IEEE Trans. Ind. Electron., vol. 62, no. 7, pp. 4537–4551, 2015.
[18] S. Jain and V. Sonti, “A Highly Efficient and Reliable Inverter Configuration Based Cascaded Multilevel Inverter for PV Systems,” IEEE Trans. Ind. Electron., vol. 64, no. 4, pp. 2865–2875, Apr. 2017.
[19] R. S. Figueredo, K. C. M. de Carvalho, N. R. N. Ama, and L. Matakas, “Leakage current minimization techniques for single-phase transformerless grid-connected PV inverters – An overview,” in 2013 Brazilian Power Electronics Conference, 2013, pp. 517–524.
[20] N. Vazquez, M. Rosas, C. Hernandez, E. Vazquez, and F. J. Perez-Pinal, “A new common-mode transformerless photovoltaic inverter,” IEEE Trans. Ind. Electron., vol. 62, no. 10, pp. 6381–6391, 2015.
[21] R.-T. Li, C. N. M. Ho, and E.-X. Chen, “Active Virtual Ground – Single Phase Transformerless Grid-Connected Voltage Source Inverter Topology,” IEEE Trans. Power Electron., vol. 33, no. 2, pp. 1–1, 2017.
[22] J. Giacomini, L. Michels, H. Pinheiro, and C. Rech, “Active Damping Scheme for Leakage Current Reduction in Transformerless Three-phase Grid-connected PV Inverters,” IEEE Trans. Power Electron., vol. 33, no. 5, pp. 1–1, 2017.
[23] X. Guo, R. He, J. Jian, Z. Lu, X. Sun, and J. M. Guerrero, “Leakage current elimination of four-leg inverter for transformerless three-phase PV systems,” IEEE Trans. Power Electron., vol. 31, no. 3, pp. 1841–1846, 2016.
[24] L. Wang, Y. Shi, Y. Shi, R. Xie, and H. Li, “Ground Leakage Current Analysis and Suppression in a 60-kW 5-Level T-Type Transformerless SiC PV Inverter,” IEEE Trans. Power Electron., vol. 33, no. 2, pp. 1271–1283, 2018.
[25] J. C. Hernandez, P. G. Vidal, and F. Jurado, “Guidelines to requirements for protection against electric shock in PV generators,” in IEEE Power Engineering Society General Meeting, 2005, pp. 576–581.
[26] VDE, “Stationary Electrical Energy Storage Systems intended for Connection to the Low Voltage Grid,” VDE-AR-E 2510-2, 2015.
[27] A. Ginart, A. Salazar, and R. Liou, “Transformerless Bidirectional Inverter for Residential Battery Storage Systems,” IEEE Green Technol. Conf., vol. 2016–April, pp. 18–23, 2016.
[28] S. R. Madeti and S. N. Singh, “A comprehensive study on different types of faults and detection techniques for solar photovoltaic system,” Sol. Energy, vol. 158, pp. 161–185, Dec. 2017.
[29] J. Flicker and J. Johnson, “Photovoltaic ground fault detection recommendations for array safety and operation,” Sol. Energy, vol. 140, pp. 34–50, Dec. 2016.
[30] B. Li, Y. Li, and T. Ma, “Research on earthing schemes in LV microgrids,” in 2011 International Conference on Advanced Power System Automation and Protection, 2011, pp. 1003–1007.
[31] R. W. Erickson, Fundamentals of Power Electronics. Secaucus, NJ, USA: Kluwer Academic Publishers, 2000.
[32] C. D. Schwertner, L. V. Bellinaso, H. L. Hey, and L. Michels, “Supervisory control for stand-alone photovoltaic systems,” 2013 Brazilian Power Electron. Conf., pp. 582–588, Oct. 2013.
[33] International Electrotechnical Commission, “Safety of power converters for use in photovoltaic power systems. Part 2 – Particular requirements for inverters,” IEC 62109-2, 2011.
[34] International Electrotechnical Commission, “Safety of power converters for use in photovoltaic power systems. Part 1 – General Requirements,” IEC 62109-1, 2010.
[35] International Electrotechnical Commission, “Methods of measurement of touch current and protective conductor current,” IEC 60990, 2016.

Seja um

A afiliação à SOBRAEP permite aos sócios (Efetivos, Aspirantes e Corporativos) acesso completo ao site da SOBRAEP e descontos em inscrições de alguns congressos da área, além da participação nos Webinars promovidos pela associação. Também existem três tipos de patrocínio disponíveis para o site/COBEP.