An Integrated Interlinking Converter with DC link Voltage Balancing Capability for Bipolar Hybrid Microgrid

Document Type : Power Article

Authors

1 Power systems group- Computer and electrical engineering faculty- K. N. Toosi University- Tehran- Iran

2 Electrical Engineering Department, Islamic Azad University, East Tehran Branch, Tehran, Iran

Abstract

Interlinking converter topology on bipolar hybrid microgrid is gaining increasing attention during last years. The heart of bipolar hybrid microgrid structure is the interlinking converter that plays the primary role in this structure. This interlinking converter has decisive tasks in the microgrid control system and controlling the dc-bus is one of the critical ones. This paper investigates application of a 10 switch inverter as an interlinking converter for a bipolar hybrid microgrid and aims to increase the power quality on both AC and DC side, and enhance efficiency in such systems. The 10 switch converter costs less in comparison to other multilevel converters and also diminishes volume and application costs. A modified modulation method and a novel control system is proposed for this converter which results in reducing computations for modulation, and adds the ability to control the dc-bus independently in unbalance dc bus conditions. Unlike conventional converters used for these microgrid types, this converter does not need any additional DC/DC converter to act as a balancer converter to balance dc-link pole voltages. The superiority of the proposed modulation and control strategy of 10 switch converter is studied in a simulation system, and the 10 switch converter results are compared to conventional topologies. The costs and semiconductor power loss of studied interlinking converters are evaluated and compared to prove the advantages of the proposed interlinking converter.

Keywords


]1[ حمید فلقی، مریم رمضانی و محمودرضا حقی‏فام، «تحلیل تأثیر نیروگاه‌های بادی بر قابلیت تبادل شبکه‌های انتقال در سیستم قدرت»، مجله مدل سازی در مهندسی، دوره 10، شماره 30، پاییز 1391، صفحه 61-75.
]2[ نیما امجدی و محمدرضا انصاری شهرضا، «مطالعه آنالیز شاخه ای پایداری دینامیکی ولتاژ درسیستم قدرت»، مجله مدل‌سازی در مهندسی، دوره 3، شماره 17، تابستان 1388، صفحه 1-7.
]3[ جمشید آقائی، امین رحیمی رضایی و محمدرضا کریمی، «هماهنگی نیروگاه‌های بادی و دستگاه‌های ذخیره‌ساز سیستم قدرت در مسئله برنامه‌ریزی امنیت-مقید مشارکت واحدها با استفاده از بهینه‌سازی استوار»، مجله مدل‌سازی در مهندسی، دوره 16، شماره 53، تابستان 1397، صفحه 207-220.
[4] P.C. Loh, D. Li, Y.K. Chai and F. Blaabjerg, "Autonomous control of interlinking converter with energy storage in hybrid AC-DC microgrid", IEEE Transactions on Industry Applications, Vol. 49, No. 3, 2013, pp. 1374–1382.
[5] V. Mortezapour and H. Lesani, "Hybrid AC/DC microgrids: A generalized approach for autonomous droop-based primary control in islanded operations", International Journal of Electrical Power & Energy Systems, Vol. 93, 2017, pp. 109–118.
[6] M. Shahparasti, M. Mohamadian, P.T. Baboli and A. Yazdianp, "Toward power quality management in hybrid AC-DC microgrid using LTC-L utility interactive inverter: Load voltage-grid current tradeoff", IEEE Transactions on Smart Grid, Vol. 8, No. 2, 2017, pp. 857–867.
[7] P. Shamsi and B. Fahimi, "Stability assessment of a DC distribution network in a hybrid micro-grid application", IEEE Transactions on Smart Grid, Vol. 5, No. 5, 2014, pp. 2527–2534.
[8] H. Kakigano, Y. Miura and T. Ise, "Low-voltage bipolar-type dc microgrid for super high quality distribution", IEEE Transactions on Power Electronics, Vol. 25, No. 12, 2010, pp. 3066–3075.
[9] R. Teodorescu, M. Liserre and P. Rodríguez, Grid Converters for Photovoltaic and Wind Power Systems, Wiley, USA, 2011.
[10] P. Najafi, A. Rajaei, M. Mohamadian and A. Yazdian Varjani, “Design considerations of Vienna rectifier-B4 converter for wind energy application”, 5th Annual International Power Electronics, Drive Systems and Technologies Conference, Tehran, Iran, 2014.
[11] A. Gupta, S. Doolla and K. Chatterjee, "ybrid AC-DC Microgrid: Systematic Evaluation of Control Strategies", IEEE Transactions on Smart Grid, Vol. 3053, 2017, pp. 1–14.
[12] M. Baharizadeh, H.R. Karshenas and J.M. Guerrero, "An improved power control strategy for hybrid AC-DC microgrids", International Journal of Electrical Power & Energy Systems, Vol. 95, 2018, pp. 364–373.
[13] K. Sheshyekani, J. Khajesalehi, M. Hamzeh and S. Dadjo Tavakoli, "Decentralised voltage balancing in bipolar dc microgrids equipped with trans-z-source interlinking converter", IET Renewable Power Generation, Vol. 10, No. 5, 2016, pp. 703–712.
[14] S. Peyghami, H. Mokhtari and F. Blaabjerg, "Autonomous Operation of a Hybrid AC/DC Microgrid with Multiple Interlinking Converters", IEEE Transactions on Smart Grid, Vol. 3053, No. c, 2017, pp. 1–1.
[15] L. Mihalache, “A hybrid 2/3 level converter with minimum switch count”, 41st IAS Annual Meeting. Conference Record of the 2006 IEEE, Vol. 2, No. 1, 2006. pp. 611–618.
[16] F. Wang, "Sine-triangle versus space-vector modulation for three-level PWM voltage-source inverters", IEEE Transactions on Industry Applications, Vol. 38, No. 2, 2002, pp. 500–506.
[17] Z. Zhou, M.S. Khanniche, P. Igic, S. T. Kong, M. Towers and P. A. Mawby, "A fast power loss calculation method for long real time thermal simulation of IGBT modules for a three-phase inverter system", International Journal of Numerical Modelling: Electronic Networks, Devices and Fields, Vol. 19, No. 1, 2006, pp. 33–46.
[18] J.W. Kolar, "Losses in PWM inverters using IGBTs", IEE Proceedings-Electric Power Applications, Vol. 142, No. 4, 1995, p. 285.