Integrated Modeling of Bidirectional Solid-State Transformers: Rectifier, DC to DC Converter and Inverter Stages
Subject Areas : electrical and computer engineeringhamed molla-ahmadian 1 * , morteza shafiei 2 , javid khorasani 3
1 - khorasan Institute of Higher Education
2 - Khorasan Institute of Higher Educatio
3 - Khorasan Institute of Higher Education
Keywords: Rectifier, DC to DC converter, inverter, solid state transformer, dynamic model, averaged model,
Abstract :
: One of the new and growing equipment in modern power networks is solid state or power electronic transformer. These types of transformers are based on power semiconductor switches and high frequency transformers. Compared to traditional transformers, it has several capabilities such as the ability to operate with input voltage variations in amplitude and frequency, automatic regulation of output voltage and input power factor correction. The investigated transformer has the ability to transfer power in both directions and has three stages, including the rectifier, the middle stage and the inverter stage. This transformer has a large number of semiconductor switches and its modeling, analysis, design and simulation is difficult and complex. In particular, real-time simulation of these transformers with conventional models is not possible. In these cases, the use of averaging theory seems to be the appropriate solution. In this paper, the averaging theory is applied to a solid-state transformer and its modeling is done in a simple and powerful way with the ability to study real-time, transient and steady states performance. The proposed modeling includes differential equations and equivalent circuits and offers an integrated transformer model with the ability to study the interaction between stages as a part of power system. The presented models are used in simulation of smart grids, DC microgrids and connection of distributed generation sources to the grid, as well as analysis and design of solid-state transformer behavior in areas such as renewable energies and electrical transportation. In addition to the proposed modeling, the closed-loop control structure has been implemented for all three stages. Transformer simulation is performed by implementing differential equations in SIMULINK/MATLAB software and verified the proposed model.
[1] B. Umar, Y. Jibril, B. Jimoh, A. B. Kunya, Y. A. Maiwada, S. Aliyu, and M. Mohammed, "Glance into solid-state transformer technology: a mirror for possible research areas," J. of Applied Materials and Technology, vol. 2, no. 1, pp. 1-13, Oct. 2020.
[2] F. Ferdowsi, H. Vahedi, A. Jafarian Abianeh, C. S. Edrington, and T. Elmezyani, "A data-driven real-time stability metric for SST-based microgrids," Int. J. of Electrical Power & Energy Systems, vol. 134, ArticleID: 107397, Jan. 2022.
[3] L. Heinemann and G. Mauthe, "The universal power electronics-based distribution transformer, an unified approach," in Proc. 32nd IEEE Annual Power Electronics Specialists Conf., vol. 2, pp. 504-509, Vancouver, BC, Canada, 17-21 Jun. 2001.
[4] J. E. Huber and J. W. Kolar, "Volume/weight/cost comparison of a 1 MVA 10 kV/400 V solid-state against a conventional low-frequency distribution transformer," in Proc. of the IEEE Energy Conversion Congress and Exposition, pp. 4545-4552, Pittsburgh, PA, USA, 14-18 Sept. 2014.
[5] M. Liserre, G. Buticchi, M. Andresen, G. I. D. Carne, L. Ferreira Costa, and Z. X. Zou, "The smart transformer impact on the electric grid and technology challenges," IEEE Industrial Electronics Magazine, vol. 10, no. 2, pp. 46-58, Jun. 2016.
[6] V. Najmi, Modeling, Control and Design Considerations for Modular Multilevel Converters, MS Thesis, Virginia Polytechnic Institute, USA, May 2015.
[7] M. Shamshuddin, et al., "Solid state transformers: concepts, classification, and control," J. of Energies, vol. 13, no. 19, Article ID: 2319, 35pp., May 2020.
[8] M. E. Adabi and J. A. Martinez-Velasco, "Solid state transformer technologies and applications: a bibliographical survey," AIMS Energy, vol. 6, no. 2, pp. 291-338, 2018.
[9] L. F. Costa, G. De Carne, G. Buticchi, and M. Liserre, "The smart transformer: a solid-state transformer tailored to provide ancillary services to the distribution grid," IEEE Power Electronics Magazine, vol. 4, no. 2, pp. 56-67, Jun. 2017.
[10] R. Zhu, et al., "Smart transformer/large flexible transformer," CES Trans. on Electrical Machines and Systems, vol. 4, no. 4, pp. 264-274, Dec. 2020.
[11] B. D. Reddy and S. K. Sahoo, "Design of solid-state transformer," Int. J. of Advanced Research in Electrical, Electronics and Instrumentation Engineering, vol. 4, no. 1, pp. 357-364, 2015.
[12] L. Zheng, et al., "SiC-based 5-kV universal modular soft-switching solid-state transformer (M-S4T) for medium-voltage DC microgrids and distribution grids," IEEE Trans. on Power Electronics, vol. 36, no. 10, pp. 11326-11343, Oct. 2021.
[13] E. Pool-Mazun, J. Sandoval, P. Enjeti, and I. Pitel, "An integrated solid-state transformer with high-frequency isolation for EV fast-charging applications," IEEE J. of Emerging and Selected Topics in Industrial Electronics, vol. 1, no. 1, pp. 46-56, Jul. 2020.
[14] J. Zhang, J. Liu, J. Yang, N. Zhao, Y. Wang, and T. Q. Zheng, "A modified DC power electronic transformer based on series connection of full-bridge converters," IEEE Trans. on Power Electronics, vol. 34, no. 3, pp. 2119-2133, Mar. 2019.
[15] R. W. Erickson and D. Maksimovic, Fundamentals of Power Electronics, 3th Ed., Springer Int. Publishing, Switzerland AG, 2020.
[16] R. Subroto, Y. Chen, K. Lian, J. Tsai, and C. Chu, "An accurate accelerated steady-state model for high-level modular multilevel converters," IEEE Trans. on Industry Applications, vol. 57, no. 4, pp. 4278-4293, Jul. 2021.
[17] M. Daryaei, S. Khajehoddin, J. Mashreghi, and K. Afridi, "A new approach to steady-state modeling, analysis and design of power converters," IEEE Trans. on Power Electronics, vol. 36, no. 11, pp. 12746-12768, Nov. 2021.
[18] Z. Liu, K. Li, J. Wang, W. Liu, Z. Javid, and Z. Wang, "General model of modular multilevel converter for analyzing the steady-state performance optimization," IEEE Trans. on Industrial Electronics, vol. 68, no. 2, pp. 925-937, Feb. 2021.
[19] م. هجری، "مدلسازی و کنترل هیبرید سرتاسری مبدل DC-DC باک- بوست به وسیله سیستمهای دینامیکی- منطقی مخلوط،" نشريه مهندسی برق و مهندسی کامپیوتر ایران، الف- مهندسي برق، سال 17، شماره 1، صص. 12-1، بهار 1398.
[20] H. Molla-Ahmadian, F. Tahami, A. Karimpour, and N. Pariz, "Hybrid control of DC-DC series resonant converters: the direct piecewise affine approach," IEEE Trans. on Power Electronics, vol. 30, no. 3, pp. 1714-1723, Mar. 2015.
[21] H. Abu Rub, J. Holtz, and J. Rodriguez, "Medium-voltage multilevel converters state of the art, challenges, and requirements in industrial applications," IEEE Trans. Industrial Electronics, vol. 57, no. 8, pp. 2581-2596, Aug. 2010.
[22] M. Malinowski, K. Gopakumar, J. Rodriguez, and M. A. Perez, "A survey on cascaded multilevel inverters," IEEE Trans. Industrial Electronics, vol. 57, no. 7, pp. 2197-2206, Jul. 2010.
[23] A. Milczarek and M. Michna, "The enhanced average model of the smart transformer with the wye-delta connection of dual active bridges," Energies, vol. 13, no. 18, Article ID: 4613, 2020.
[24] M. E. Adabi, Advanced Modeling of Solid State Transformer, Ph.D. Thesis, CATALUNYA Polytechnic University, Barcelona, 2018.
[25] B. Khare and V. Thapar, "MATLAB simulink model of dual active bridge converter for solid state transformer," J. of Emerging Technologies and Innovative Research, vol. 8, no. 7, pp. 887-890, Jul. 2021.
[26] J. V. Missula, R. Adda, and P. Tripathy, "Averaged modeling and SRF-based closed-loop control of single-phase ANPC inverter," IEEE Trans. on Power Electronics, vol. 36, no. 12, pp. 13839-13854, Dec. 2021.
[27] D. Shah, B. Baddipadiga, M. Crow, and M. Ferdowsi, "A solid-state transformer model for proper integration to distribution networks," in Proc. North American Power Symp., NAPS19, 6 pp., Wichita, KS, USA, 13-15 Oct. 2019.
[28] J. Martinez-Velasco, S. Alepuz, F. Gonzalez-Molina, and J. Martin-Arnedo, "Dynamic average modeling of a bidirectional solid state transformer for feasibility studies and real-time implementation," Electric Power Systems Research, vol. 117, pp. 143-153, Dec. 2014.
[29] R. B. Jeyapradha and V. Rajini, "Small signal averaged transfer function model and controller design of modular solid-state transformers," ISA Trans., vol. 84, pp. 271-282, Jan. 2019.
[30] C. M. Freitas, E. H. Watanabe, and L. F. C. Monteiro, "A linearized small-signal Thévenin-equivalent model of a voltage-controlled modular multilevel converter," Electric Power Systems Research, vol. 182, Article ID: 106231, May 2020.
[31] A. Shri, A Solid-State Transformer for Interconnection Between the Medium and the Low Voltage Grid, MSc. Thesis, Delft University of Technology, Holand, Oct. 2013.
[32] S. Falcones and R. Ayyanar, "Topology comparison for solid state transformer implementation," in Proc. IEEE PES General Meeting, 8 pp., Minneapolis, MN, USA, 25-29 Jul. 2010.
[33] ج. خراسانی، م. شفیعی، ح. ملااحمدیان، م. حسینی ابرده و م. علومی، "ترانسفورماتور حالت جامد،" فصلنامه علمی آموزشی پژوهشی عصر برق (انجمن مهندسین برق و الکترونیک ایران شاخه خراسان)، سال 3، شماره 4، صص. 13-7، بهار 1395.
[34] E. Salary and M. R. Banaei, "Power quality improvement based on novel power electronic transformer," in Proc. 2nd Power Electronics, Drive Systems and Technologies Conf., pp. 286-291, Tehran, Iran, 16-17 Feb. 2011.
[35] W. van der Merwe and T. Mouton, "Solid-state transformer topology selection," in Proc. IEEE Int. Conf. on Industrial Technology, 6 pp., Churchill, VIC, Australia, 10-13 Feb. 2009.
[36] S. Bhattacharya, et al., "Design and development of generation-I silicon based solid state transformer," in Proc. 25th Annual IEEE Applied Power Electronics Conf. and Exposition, APEC'10, pp. 1666-1673, Palm Springs, CA, USA, 21-25 Feb. 2010.
[37] G. I. Ortiz and J. W. Kolar, Solid State Transformer Concepts in Traction and Smart Grid Applications, Power Electronic Systems Laboratory ETH, Swiss, 2011.
[38] T. Ponraj and A. George, "A solid state transformer integrating distributed generation and storage," Int. J. of Innovative Research in Computer and Communication Engineering, vol. 2, no. 1, pp. 4029-4035, 2014.
[39] S. Bhuskute and V. S. Pawar, "Solid state transformer for smart grid system application," Int. J. of Research in Electronics and Computer Engineering, vol. 3, no. 2, pp. 90-93, Jun. 2015.