1915

Analyzes of Flyback DC-DC Converter for Submodule Level Maximum Power Point Tracking in Off-grid Photovoltaic Systems

Submodule level maximum power point tracking (MPPT) systems have become popular due to its outstanding performance in partial shading conditions (PSCs) and basic algorithm requirement. MPPT is realized by DC-DC converters. They are power processing units between photovoltaic (PV) module and resistive load. Among DC-DC converter topologies, the flyback is a proper choice since it can either increase or decrease the voltage. Furthermore, power level is small in submodule level (SML) MPPT applications. In this study, analyzes and power circuit design of a flyback converter for continuous conduction mode (CCM) is carried out firstly. Then, the performance of the flyback converter on the SML MPPT system and its superiority over the module level MPPT is shown by using same converter topology and perturb and observe (P&O) algorithm. In order to validate the superior performance of SML MPPT, it is compared with module level MPPT in MATLAB/Simulink environment. Results show that SML MPPT guarantees global MPPT in any PSCs with any kind of basic MPPT algorithm. On the other hand, module level MPPT fails in many PSCs with the same algorithm. According to simulation results, SML MPPT generated more power by 61.2% in average than module level MPPT systems in simulation studies.

PDF

___

Başoğlu M.E., Çakır B., An improved incremental conductance based MPPT approach for PV modules, Turkish Journal of Electrical Engineering & Computer Sciences, vol. 23, no. 6, pp. 1687-1697, 2015.
Başoğlu M.E., Çakır B., Comparisons of MPPT performances of isolated and non-isolated DC-DC converters by using a new approach, Renewable & Sustainable Energy Reviews, vol. 60, pp. 1100-1113, 2016.
Başoğlu M.E., Çakır B., A novel voltage-current characteristic based global maximum power point tracking algorithm in photovoltaic systems, Energy, vol. 112, pp. 153-163, 2016.
Kasa N., Iida T., Chen L., Flyback inverter controlled by sensorless current MPPT for photovoltaic power system, IEEE Transactions on Industrial Electronics, vol. 52, no. 4, pp. 1145-1152, 2005.
Mazumdar P, Enjeti P.N., Balog R.S., Analysis and design of smart PV modules, IEEE Journal of Emerging and Selected Topics in Power Electronics, vol. 2, no. 3, pp. 451-459, 2014.
Pragallapati N., Agarwal V., Flyback configuration based micro-inverter with distributed MPPT of partially shaded PV module and energy recovery scheme, IEEE 39th Photovoltaic Specialists Conference, Tampa, USA, pp. 2927-2931, 2013.
Lee J., Lee J. S., Lee K., Current sensorless MPPT method for a PV flyback microinverters using a dual-mode, International Power Electronics Conference, Hiroshima, pp. 532-537, 2014.
Kim Y., Kim J., Ji Y., Won C. Lee T., Flyback inverter using voltage sensorless MPPT for AC module systems, International Power Electronics Conference, Sapporo, pp. 948-953, 2010.
Zhang W.P., Li J., Mao P., A novel isolated-port voltage equalizer for photovoltaic systems under mismatch conditions, 43rd Annual Conference of the IEEE Industrial Electronics Society, Beijing, pp. 639-644, 2017.
Sher H.A., Rizvi A.A., Addoweesh K.E., Al-Haddad K., A., Single-stage stand-alone photovoltaic energy system with high tracking efficiency, IEEE Transactions on Sustainable Energy, vol. 8, no. 2, pp. 755-782, 2017.
Pilawa-Podgurski R.C.N., Perreault D.J., Submodule integrated distributed maximum power point tracking for solar photovoltaic applications, IEEE Transactions on Power Electronics, vol. 28, no. 6, pp. 2957-2967, 2013.
Grasso A.D., Pennisi S., Ragusa M., Tina G.M., Ventura C., Performance evaluation of a multistring photovoltaic module with distributed DC-DC converters, IET Renewable Power Generation, vol. 9, no. 8, pp. 935-942, 2015.
Qin S., Barth C.B., Pilawa-Podgurski R.C.N., Enhancing microinverter energy capture with submodule differential power processing, IEEE Transactions on Power Electronics, vol. 31, no. 5, pp. 3575-3585, 2016.
Wang F., Zhu T., Zhuo F., Yang Y., Analysis and comparison of FPP and DPP structure based DMPPT PV system, 8th International Power Electronics and Motion Control Conference, Hefei, pp. 1-5, 2016.
Pragallapati N., Agarwal V., Distributed PV power extraction based on a modified interleaved SEPIC for nonuniform irradiation conditions, IEEE Journal of Photovoltaics, vol. 5, no. 5, pp. 1442-1453, 2015.
Bose S.M., Badawy O., Sozer Y., A novel differential power processing architecture for a partially shaded PV string using distributed control, IEEE Energy Conversion Congress and Exposition, Portland, pp. 6220-6227, 2018.
TopSwitch Flyback Design Methodology, Application Note AN-16, https://ac-dc.power.com/system/files_force/product-docs/an16.pdf, (accessed: 20.01.2019).
Kazmierczuk, M.K., 2008, Pulse-width modulated DC-DC power converters, John Wiley & Sons, Ltd. United Kingdom, pp. 191-195.