Document Type : Research Article

Authors

1 Faculty of Technology and Engineering, Shahrekord University, Shahrekord, Iran

2 Department of Energy Technology, Aalborg University, Aalborg, Denmark

Abstract

This study investigates a new double-stage single-phase Grid-Connected (GC) Photo-Voltaic (PV) system. This PV system includes a DC-DC Positive Output Super Lift Luo Converter (POSLLC) and a single-phase inverter connected to a grid through an RL filter. Due to its advantages, the POSLLC was used between PV panel and inverter instead of the conventional boost converter. The state space equations of the system were solved. By using two Sliding Mode Controls (SMCs), PV panel voltage and POSLLC inductor current were controlled and the designed controls were compared. Two of these SMCs included a simple Sign Function Control (SFC) and a conventional SMC. To control the power injected into the grid with a unity power factor, an SMC was used. Perturb and Observe (P&O) method was employed to reach maximum power of the PV panel. The Maximum Power Point Tracking (MPPT) control generated the voltage reference of the PV panel. Similar controls were used for the boost converter instead of POSLLC. The obtained results were compared.

Keywords

Main Subjects

1.     Yang, Y. and Blaabjerg, F., "Overview of single-phase grid-connected photovoltaic systems", Electric Power Components and Systems, Vol. 43, No. 12, (2015), 1352-1363. (https://doi.org/10.1080/15325008.2015.1031296).
2.     Jafari, M., Ghadamian, H. and Seidabadi, L., "An experimental and comparative analysis of the battery charge controllers in off-grid PV systems", Journal of Renewable Energy and Environment (JREE), Vol. 5, No. 4, (2018), 46-53. (https://dx.doi.org/10.30501/jree.2018.95298)
3.     Rahmani, M., Faghihi, F., Moradi CheshmehBeigi, H. and Hosseini S.M., "Frequency control of islanded microgrids based on fuzzy cooperative and influence of STATCOM on frequency of microgrids", Journal of Renewable Energy and Environment (JREE), Vol. 5, No. 4, (2018), 27-33. (https://dx.doi.org/10.30501/jree.2018.94119).
4.     Kjaer, S.B., Pedersen, J.K. and Blaabjerg, F., "A review of single-phase grid-connected inverters for photovoltaic modules", IEEE Transactions on Industry Applications, Vol. 41, No. 5, (2005), 2649-2663. (https://doi.org/10.1109/tia.2005.853371).
5.     Fallahzadeh, S.A.A., Abjadi, N.R. and Kargar, A., "Double-stage grid-connected photovoltaic system with POSLL converter using PI resonant controller", Proceedings of 5th International IEEE Conference on Control, Instrumentation, and Automation (ICCIA), Iran, (2017), 155-160. (https://doi.org/10.1109/icciautom.2017.8258670).
6.     Khan, O. and Xiao, W., "An efficient modeling technique to simulate and control submodule integrated PV system for single phase grid connection", IEEE Transactions on Sustainable Energy ,Vol. 7, No. 1, (2016), 96-107.(https://doi.org/10.1109/tste.2015.2476822).
7.     Xiao, W., Edwin, F.F., Spagnuolo, G. and Jatskevich, J., "Efficient approaches for modelingand simulating photovoltaic power systems", IEEE Journal of Photovoltaics, Vol. 3, (2013), 500-508. (https://doi.org/10.1109/jphotov.2012.2226435).
8.     Harb, S., Hu, H., Kutkut, N., Batarseh, I. and John Shen, Z., "A three-port photovoltaic (PV) micro-inverter with power decoupling capability", Proceedings of 2011 Twenty-Sixth Annual IEEE Applied Power Electronics Conference and Exposition (APEC), (2011). (https://doi.org/10.1109/APEC.2011.5744598).
9.     Lotfi Nejad, M., Poorali, B., Adib, E. and Motie Birjandi, A.A., "New cascade boost converter with reduced losses", IET Power Electronics, Vol. 9, No. 6, (2016), 1213-1219. (https://doi.org/10.1049/iet-pel.2015.0240).
10.   Sosa, J.M., Martinez-Rodriguez, P.R., Vazquez, G. and Nava-Cruz, J.C., "Control design of a cascade boost converter based on the averaged model", IEEE International Autumn Meeting on Power Electronics and Computing (ROPEC), Mexico, (2013). (https://doi.org/10.1109/ROPEC.2013.6702718).
11.   Miao, Z. and Luo, F.L., "Analysis of positive output super-lift converter in discontinuous conduction mode", International Conference on Power System Technology, Singapore, (2004), 828-833. (https://doi.org/10.1109/icpst.2004.1460108).
12.   Jiao, Y., Luo, F.L. and Zhu, M., "Generalised modelling and sliding mode control for n-cell cascade super-lift DC-DC converters", IET Power Electronics, Vol. 4, No. 5,  (2011), 532-540. (https://doi.org/10.1049/iet-pel.2010.0049).
13.   Luo, F.L. and Ye, H., "Positive output super-lift converters", IEEE Transactions on Power Electronics, Vol. 18, No. 1, (2003), 105-113. (https://doi.org/10.1109/TPEL.2002.807198).
14.   Luo, F.L., "Analysis of super-lift Luo-converters with capacitor voltage drop", 3rd IEEE Conference on Industrial Electronics and Applications, Singapore, (2008), 417- 422.  (https://doi.org/10.1109/iciea.2008.4582550).
15.   Vinoth, K. and Ramesh, B., "A modified LUO converter for hybrid energy system FED grid tied inverter", International Journal of Engineering and Advanced Technology (IJEAT), Vol. 9, No. 1, (2019), 1515-1521. (https://doi.org/10.35940/ijeat.a1288.109119).
16.   Narmadha, T.V., Velu, J. and Sudhakar, T.D., "Comparison of performance measures for PV based super-lift Luo-converter using hybrid controller with conventional controller", Indian Journal of Science and Technology, Vol. 9, No. 29, (2016), 1-8. (https://doi.org/10.17485/ijst/2016/v9i29/89937).
17.   Gnanavadivel, J., Yogalakshmi, P., Senthil Kumar, N. and Krishna Veni, K.S., "Design and development of single phase AC–DC discontinuous conduction mode modified bridgeless positive output Luo converter for power quality improvement", IET Power Electronics, Vol. 12, No. 11, (2019), 2722-2730. (https://doi.org/10.1049/iet-pel.2018.6059).
18.   Selvaraj, J. and Rahim, N.A., "Multilevel inverter for grid-connected PV system employing digital PI controller", IEEE Transactions on Industrial Electronics, Vol. 56, No. 1, (2009), 149-158. (https://doi.org/10.1109/tie.2008.928116).
19.   Chowdhury, M.A., "Dual-loop H1 controller design for a grid-connected singlephase photovoltaic system", Solar Energy, Vol. 139, (2016), 640-649. (https://doi.org/10.1016/j.solener.2016.10.039).
20.   Bourguiba, I., Houari, A., Belloumi, H. and Kourda, F., "Control of single-phase grid connected photovoltaic inverter", 4th International Conference on Control Engineering & Information Technology (CEIT-2016), Tunisia, (2016). (https://doi.org/10.1109/ceit.2016.7929116).
21.   Sangwongwanich, A., Yang, Y. and Blaabjerg., F., "A sensorless power reserve control strategy for two-stage grid-connected PV systems", IEEE Transactions on Power Electronics, Vol. 32, No. 11,  (2019), 8859-8869. (https://doi.org/10.1109/tpel.2017.2648890).
22.   Huang, L., Qiu, D., Xie, F., Chen, Y. and Zhang, B., "Modeling and stability analysis of a single-phase two-stage grid-connected photovoltaic system", Energies, Vol. 10, No. 12, (2017), 1-14. (https://doi.org/10.3390/en10122176).
23.   Hao, X., Xu, Y., Liu, T., Huang, L. and Chen, W., "A sliding-mode controller with multiresonant sliding surface for single-phase grid-connected VSI with an LCL filter", IEEE Transactions on Power Electronics, Vol. 28, No. 5, (2013), 2259-2268. (https://doi.org/10.1109/tpel.2012.2218133).
24    Fallahzadeh, S.A.A., Abjadi, N.R., Kargar, A. and Mahdavi. M., "Sliding mode control of single phase grid connected PV system using sign function",  IEEE 4th International Conference on Knowledge-Based Engineering and Innovation (KBEI), Iran, (2017), 391-397. (https://doi.org/10.1109/KBEI.2017.8325009).
25.   Mahmud, M.A., Pota, H.R., Hossain, M.J. and Roy, N., "Robust partial feedback linearization stabilization scheme for three-phase grid-connected photovoltaic systems", IEEE Transactions on Power Delivery, Vol. 29, No. 3, (2014), 1221-1230. (https://doi.org/10.1109/jphotov.2013.2281721).
26.   Aourir, M., Aboulooifa, A., Lachkar, I., Hamdoun, A., Giri, F. and Cuny, F., "Nonlinear control of PV system connected to single phase grid through half bridge power inverter", Proceedings of 20th IFAC World Congress, Vol. 50, No. 1, (2017), 741-746. (https://doi.org/10.1016/j.ifacol.2017.08.241).
27.   Fallahzadeh S.A.A., Abjadi, N.R. and Kargar, A., "Decoupled active and reactive power control of a grid-connected inverter-based DG using adaptive input-output feedback linearization", Iranian Journal of Science and Technology, Transactions of Electrical Engineering, (2020), 1-10. (https://doi.org/10.1007/s40998-020-00319-3).
28.   Roy, T.K., Mahmud, M.A., Hossain, M.J. and Oo, A.M.T., "Nonlinear backstepping controller design for sharing active and reactive power in three phase grid-connected photovoltaic systems", Australasian Universities Power Engineering Conference (AUPEC), NSW, (2015), 1-6. (https://doi.org/10.1109/aupec.2015.7324866).
29.   Mahdavi, M., Shahriari-Kahkehi M. and Abjadi, N.R., "An adaptive estimator-based sliding mode control scheme for Uncertain POESLL converter", IEEE Transactions on Aerospace and Electronic systems, (2019), Vol. 55, No. 6, 3551-3560. (https://doi.org/10.1109/TAES.2019.2908272).
30.   Chaibi, Y., Salhi, M. and El-Jouni, A., "Sliding mode controllers for standalone pv systems: Modeling and approach of control", International Journal of Photoenergy, Vol. 2019, (2019), 1-12. (https://doi.org/10.1155/2019/5092078).
31.   Ali, K., Khan, L., Khan, Q., Ullah, S., Ahmad, S., Mumtaz, S., Karam, F.W. and Naghmash, A., "Robust integral backstepping based nonlinear mppt control for a pv system", Energies, Vol. 12, No. 16, (2019), 1-20. (https://doi.org/10.3390/en12163180).
32.   Fallahzadeh, S.A.A., Abjadi, N.R., Kargar, A. and Blaabjerg. F., "Nonlinear control for positive output super lift Luo converter in stand alone photovoltaic system", International Journal of Engineering, Vol. 33, (2020), 237-247. (https://doi.org/10.5829/ije.2020.33.02b.08).
33.   Jendoubia, A., Tlilia, F., and Faouzi Bachaa, F., "Sliding mode control for a grid connected PV-system using interpolation polynomial MPPT approach", Elsevier Mathematics and Computers in Simulation, Vol. 167, (2020), 208-218. (https://doi.org/10.1016/j.matcom.2019.09.007).
34.   Miqoi, S., Ougli, A.E. and Tidhaf, B., "Adaptive fuzzy sliding mode based MPPT controller for a photovoltaic water pumping system", International Journal of Power Electronics and Drive System (IJPEDS), Vol. 10, No. 1, (2019), 414-422. (https://doi.org/10.11591/ijpeds.v10.i1.pp414-422).
35.   Kim, I.S., "Sliding mode controller for the single-phase grid-connected photovoltaic system", Applied Energy, Vol. 83, (2006), 1101-1115. (https://doi.org/10.1016/j.apenergy.2005.11.004).
36.   Ramirez H.R. and Ortigoza, R.S., Control design and techniques in power electronics devices, Springer-Verlag, London, (2006). (https://doi.org/10.1007/1-84628-459-7_3).
37.   Xiao, W., Photovoltaic power system modeling, design, and control, Wiely, Australia, (2017). (https://doi.org/10.1002/9781119280408).
38.   Pavlovic., T., The Sun and photovoltaic technologies, Springer, University of Niš, Serbia, (2020). (https://doi.org/10.1007/978-3-030-22403-5).