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Tek Fazlı Yarı-Empedans Kaynaklı İnverterlerin Anahtarlama Kaybını Azaltmak İçin Yeni Taşıyıcı Temelli Kontrol Stratejisi

Yıl 2023, , 571 - 580, 31.12.2023
https://doi.org/10.24012/dumf.1331641

Öz

Günümüzde enerji giderek daha önemli hale gelmektedir, çünkü üretim maliyetleri ve fosil kaynakların azalması gibi etmenler etkili olmaktadır. Bu durum, enerjinin son kullanıcılara en verimli şekilde ulaştırılması gereken kritik bir sorun olarak ortaya çıkmaktadır. Bu bağlamda, yakıt hücreleri, rüzgar enerjisi ve fotovoltaik enerji gibi doğru akım (DA) güç kaynakları tarafından üretilen enerjiyi, son kullanıcılar için kullanılabilir hale getirmek için güç elektroniği devreleri arasında inverterler yer almaktadır. Aynı şekilde, fotovoltaik sistemlerin daha yüksek verimliliğini sağlamak için maksimum gücün elde edilmesini veya regüle edilmesini sağlayan kontrol yapıları ile iki veya üç aşamalı sistemler gerekmektedir. Empedans kaynaklı inverterler, fotovoltaik panellerden tek aşamada maksimum gücü sağlama ve son kullanıcıya ulaştırma yeteneği nedeniyle geleneksel inverterlere göre avantajlıdır ve en yaygın kullanılan taşıyıcı temelli anahtarlama yapısı "Basit Arttırma Kontrolü" olarak bilinmektedir. Bu çalışmada, empedans kaynaklı inverterler için anahtarlama sayısını ve buna bağlı olarak ortaya çıkan anahtarlama kayıplarını azaltmaya yönelik taşıyıcı temelli yeni bir anahtarlama yapısı tasarlanmıştır. "Basit Arttırma Kontrolü" yapısından esinlenerek, bu çalışmada mevcut taşıyıcı sinyale paralel yeni bir sinyal kullanılarak anahtarlama sayısı %66 oranında azaltılmış ve çıkış geriliminde herhangi bir bozulma olmamıştır. Sonuç olarak, bu yöntem devre anahtarlama elemanları üzerindeki anahtarlama kayıplarını azaltır ve empedans kaynaklı inverterlerin verimliliğini artırma potansiyelini ortaya koyar.

Kaynakça

  • [1] N. Vázquez ve J. V. López, “11 - Inverters”, içinde Power Electronics Handbook (Fourth Edition), M. H. Rashid, Ed., Butterworth-Heinemann, 2018, ss. 289-338. doi: 10.1016/B978-0-12-811407-0.00011-8.
  • [2] S.-H. Lee, S.-G. Song, S.-J. Park, C.-J. Moon, ve M.-H. Lee, “Grid-connected photovoltaic system using current-source inverter”, Solar Energy, c. 82, sy 5, ss. 411-419, May. 2008, doi: 10.1016/j.solener.2007.10.006.
  • [3] S. Samerchur, S. Premrudeepreechacharn, Y. Kumsuwun, ve K. Higuchi, “Power control of single-phase voltage source inverter for grid-connected photovoltaic systems”, içinde 2011 IEEE/PES Power Systems Conference and Exposition, Phoenix, AZ, USA: IEEE, Mar. 2011, ss. 1-6. doi: 10.1109/PSCE.2011.5772504.
  • [4] J. Bauer, “Single Phase Voltage Source Inverter Photovoltaic Application”, Acta Polytech, c. 50, sy 4, Oca. 2010, doi: 10.14311/1217.
  • [5] Fang Zheng Peng, “Z-source inverter”, IEEE Trans. on Ind. Applicat., c. 39, sy 2, ss. 504-510, Mar. 2003, doi: 10.1109/TIA.2003.808920.
  • [6] J. Anderson ve F. Z. Peng, “Four quasi-Z-Source inverters”, içinde 2008 IEEE Power Electronics Specialists Conference, Rhodes, Greece: IEEE, Haz. 2008, ss. 2743-2749. doi: 10.1109/PESC.2008.4592360.
  • [7] B. Farhangi ve S. Farhangi, “Comparison of z-source and boost-buck inverter topologies as a single phase transformer-less photovoltaic grid-connected power conditioner”, içinde 37th IEEE Power Electronics Specialists Conference, Jeju, Korea: IEEE, 2006, ss. 1-6. doi: 10.1109/PESC.2006.1711742.
  • [8] Miaosen Shen, Jin Wang, A. Joseph, F. Z. Peng, L. M. Tolbert, ve D. J. Adams, “Maximum constant boost control of the Z-source inverter”, içinde Conference Record of the 2004 IEEE Industry Applications Conference, 2004. 39th IAS Annual Meeting., Seattle, WA, USA: IEEE, 2004, ss. 142-147. doi: 10.1109/IAS.2004.1348400.
  • [9] F. Z. Peng, M. Shen, ve Z. Qian, “Maximum Boost Control of the Z-Source Inverter”, IEEE Trans. Power Electron., c. 20, sy 4, ss. 833-838, Tem. 2005, doi: 10.1109/TPEL.2005.850927.
  • [10] F. Zare ve J. A. Firouzjaee, “Hysteresis Band Current Control for a Single Phase Z-source Inverter with Symmetrical and Asymmetrical Z-network”, içinde 2007 Power Conversion Conference - Nagoya, Nagoya, Japan: IEEE, Nis. 2007, ss. 143-148. doi: 10.1109/PCCON.2007.372960.
  • [11] H. Zhang, Y. Liu, D. Sun, B. Ge, H. Abu-Rub, ve F. Z. Peng, “A hybrid modulation method for single-phase quasi-Z source inverter”, içinde 2014 IEEE Energy Conversion Congress and Exposition (ECCE), Pittsburgh, PA, USA: IEEE, Eyl. 2014, ss. 4444-4449. doi: 10.1109/ECCE.2014.6953729.
  • [12] S. DebBarman ve T. Roy, “Advanced Pulse Width Modulation technique for Z-Source Inverter”, içinde 2014 IEEE 6th India International Conference on Power Electronics (IICPE), Kurukshetra, India: IEEE, Ara. 2014, ss. 1-6. doi: 10.1109/IICPE.2014.7115850.
  • [13] K. Yu, J. Zhao, K. J. Tseng, F. L. Luo, ve M. Zhu, “Space vector pulse-width modulation for single-phase full-bridge Z-source inverter: SVPWM FOR SINGLE-PHASE ZSI”, Int. J. Circ. Theor. Appl., c. 43, sy 3, ss. 374-389, Mar. 2015, doi: 10.1002/cta.1946.
  • [14] U. Devaraj, S. Ramalingam, ve D. Sambasivam, “Evaluation of Modulation Strategies for Single-Phase Quasi-Z-Source Inverter”, J. Inst. Eng. India Ser. B, c. 100, sy 4, ss. 333-341, Ağu. 2019, doi: 10.1007/s40031-019-00378-z.
  • [15] I. Grgic, M. Bubalo, D. Vukadinovic, ve M. Basic, “Power Losses Analysis of a Three-phase Quasi-Z-Source Inverter”, içinde 2020 5th International Conference on Smart and Sustainable Technologies (SpliTech), Split, Croatia: IEEE, Eyl. 2020, ss. 1-5. doi: 10.23919/SpliTech49282.2020.9243732.
  • [16] Y. Zhou, L. Liu, ve H. Li, “A High-Performance Photovoltaic Module-Integrated Converter (MIC) Based on Cascaded Quasi-Z-Source Inverters (qZSI) Using eGaN FETs”, IEEE Trans. Power Electron., c. 28, sy 6, ss. 2727-2738, Haz. 2013, doi: 10.1109/TPEL.2012.2219556.
  • [17] R. Iijima, T. Isobe, ve H. Tadano, “Loss comparison of Z-source inverter from the perspective of short-through mode implementation and type of switching device”, içinde 2015 IEEE 2nd International Future Energy Electronics Conference (IFEEC), Taipei, Taiwan: IEEE, Kas. 2015, ss. 1-6. doi: 10.1109/IFEEC.2015.7361518.
  • [18] R. Iijima, T. Isobe, ve H. Tadano, “Loss analysis of Z-source inverter using SiC-MOSFET from the perspective of current path in the short-through mode”, içinde 2016 18th European Conference on Power Electronics and Applications (EPE’16 ECCE Europe), Karlsruhe: IEEE, Eyl. 2016, ss. 1-10. doi: 10.1109/EPE.2016.7695676.
  • [19] S. Kim, J. Park, K. Lee, ve T. Kim, “Novel Pulse-width Modulation Strategy to Minimize the Switching Losses of Z-Source Inverters”, Electric Power Components and Systems, c. 42, sy 11, ss. 1213-1225, Ağu. 2014, doi: 10.1080/15325008.2014.921955.
  • [20] A. Abdelhakim, P. Davari, F. Blaabjerg, ve P. Mattavelli, “Switching Loss Reduction in the Three-Phase Quasi-Z-Source Inverters Utilizing Modified Space Vector Modulation Strategies”, IEEE Trans. Power Electron., c. 33, sy 5, ss. 4045-4060, May. 2018, doi: 10.1109/TPEL.2017.2721402.
  • [21] I. Grgić, D. Vukadinović, M. Bašić, ve M. Bubalo, “Efficiency Boost of a Quasi-Z-Source Inverter: A Novel Shoot-Through Injection Method with Dead-Time”, Energies, c. 14, sy 14, s. 4216, Tem. 2021, doi: 10.3390/en14144216.
  • [22] S. Sonar, S. Mondal, J. Ghommam, ve S. Banerjee, “An Optimized Space Vector Based Switching Algorithm With Reduced Switching Transitions for Impedance Source Inverter”, IEEE Access, c. 10, ss. 28965-28974, 2022, doi: 10.1109/ACCESS.2022.3153497.
  • [23] M. Mohammadi, J. S. Moghani, ve J. Milimonfared, “A Novel Dual Switching Frequency Modulation for Z-Source and Quasi-Z-Source Inverters”, IEEE Trans. Ind. Electron., c. 65, sy 6, ss. 5167-5176, Haz. 2018, doi: 10.1109/TIE.2017.2784346.
  • [24] A. Abdelhakim, F. Blaabjerg, ve P. Mattavelli, “Single-Phase Quasi-Z-Source Inverters: Switching Loss Reduction Using a Quasi-Sinusoidal Modulation Strategy”, içinde 2019 IEEE Applied Power Electronics Conference and Exposition (APEC), Anaheim, CA, USA: IEEE, Mar. 2019, ss. 1918-1925. doi: 10.1109/APEC.2019.8721955.
  • [25] S. Radman, M. Shahnazari, ve H. Toodeji, “New switching strategy for single-phase multilevel quasi-Z-Source inverter”, içinde 2016 7th Power Electronics and Drive Systems Technologies Conference (PEDSTC), Tehran, Iran: IEEE, Şub. 2016, ss. 403-408. doi: 10.1109/PEDSTC.2016.7556895.
  • [26] I. Roasto, D. Vinnikov, J. Zakis, ve O. Husev, “New Shoot-Through Control Methods for qZSI-Based DC/DC Converters”, IEEE Trans. Ind. Inf., c. 9, sy 2, ss. 640-647, May. 2013, doi: 10.1109/TII.2012.2224353.
  • [27] I. Grgić, D. Vukadinović, M. Bašić, ve M. Bubalo, “Calculation of Semiconductor Power Losses of a Three-Phase Quasi-Z-Source Inverter”, Electronics, c. 9, sy 10, s. 1642, Eki. 2020, doi: 10.3390/electronics9101642. [28] D. W. Hart, “Chapter 8-Inverters”, Power Electronics. Ed. by Darlene M. Schueller. McGraw-Hill, ss. 357-358, 2010.
  • [29] Y. Liu, H. Abu-Rub, B. Ge, F. Blaabjerg, O. Ellabban, ve P. C. Loh, “Voltage-Fed Z-Source/Quasi-Z-Source Inverters”, içinde Impedance Source Power Electronic Converters, IEEE, 2016, ss. 20-34. Erişim: 09 Mart 2023. [Çevrimiçi]. Erişim adresi: https://ieeexplore.ieee.org/document/7572766
  • [30] Y. Liu, H. Abu‐Rub, B. Ge, F. Blaabjerg, O. Ellabban, ve P. C. Loh, Impedance Source Power Electronic Converters, 1. bs. Wiley, 2016. doi: 10.1002/9781119037088.

Novel Carrier-Based Control Strategy for Reduced Switching Losses in Single-Phase Quasi-Impedance Source Inverters

Yıl 2023, , 571 - 580, 31.12.2023
https://doi.org/10.24012/dumf.1331641

Öz

Energy is becoming increasingly crucial today due to factors such as production costs and the decline of fossil resources. This situation has brought forth a critical issue of delivering energy to end-users in the most efficient way. In this context, inverters play a significant role in converting energy generated from direct current (DC) power sources such as fuel cells, wind energy, and photovoltaic energy into usable form for end-users. Similarly, to achieve higher efficiency in photovoltaic systems, control structures enabling the extraction or regulation of maximum power require two or three-stage systems. Impedance-source inverters, known for their ability to provide maximum power from photovoltaic panels in a single stage and deliver it to end-users, offer advantages over traditional inverters and utilize the widely used carrier-based switching structure known as "Simple Boost Control." In this study, a carrier-based new switching structure has been designed for impedance-source inverters to reduce the number of switching operations and associated switching losses. Drawing inspiration from the "Simple Boost Control" structure, this study reduces the number of switching operations by 66% using a parallel secondary carrier signal without any distortion in the output voltage. As a result, this method reduces switching losses in circuit switching elements, demonstrating the potential to enhance the efficiency of impedance-source inverters.

Kaynakça

  • [1] N. Vázquez ve J. V. López, “11 - Inverters”, içinde Power Electronics Handbook (Fourth Edition), M. H. Rashid, Ed., Butterworth-Heinemann, 2018, ss. 289-338. doi: 10.1016/B978-0-12-811407-0.00011-8.
  • [2] S.-H. Lee, S.-G. Song, S.-J. Park, C.-J. Moon, ve M.-H. Lee, “Grid-connected photovoltaic system using current-source inverter”, Solar Energy, c. 82, sy 5, ss. 411-419, May. 2008, doi: 10.1016/j.solener.2007.10.006.
  • [3] S. Samerchur, S. Premrudeepreechacharn, Y. Kumsuwun, ve K. Higuchi, “Power control of single-phase voltage source inverter for grid-connected photovoltaic systems”, içinde 2011 IEEE/PES Power Systems Conference and Exposition, Phoenix, AZ, USA: IEEE, Mar. 2011, ss. 1-6. doi: 10.1109/PSCE.2011.5772504.
  • [4] J. Bauer, “Single Phase Voltage Source Inverter Photovoltaic Application”, Acta Polytech, c. 50, sy 4, Oca. 2010, doi: 10.14311/1217.
  • [5] Fang Zheng Peng, “Z-source inverter”, IEEE Trans. on Ind. Applicat., c. 39, sy 2, ss. 504-510, Mar. 2003, doi: 10.1109/TIA.2003.808920.
  • [6] J. Anderson ve F. Z. Peng, “Four quasi-Z-Source inverters”, içinde 2008 IEEE Power Electronics Specialists Conference, Rhodes, Greece: IEEE, Haz. 2008, ss. 2743-2749. doi: 10.1109/PESC.2008.4592360.
  • [7] B. Farhangi ve S. Farhangi, “Comparison of z-source and boost-buck inverter topologies as a single phase transformer-less photovoltaic grid-connected power conditioner”, içinde 37th IEEE Power Electronics Specialists Conference, Jeju, Korea: IEEE, 2006, ss. 1-6. doi: 10.1109/PESC.2006.1711742.
  • [8] Miaosen Shen, Jin Wang, A. Joseph, F. Z. Peng, L. M. Tolbert, ve D. J. Adams, “Maximum constant boost control of the Z-source inverter”, içinde Conference Record of the 2004 IEEE Industry Applications Conference, 2004. 39th IAS Annual Meeting., Seattle, WA, USA: IEEE, 2004, ss. 142-147. doi: 10.1109/IAS.2004.1348400.
  • [9] F. Z. Peng, M. Shen, ve Z. Qian, “Maximum Boost Control of the Z-Source Inverter”, IEEE Trans. Power Electron., c. 20, sy 4, ss. 833-838, Tem. 2005, doi: 10.1109/TPEL.2005.850927.
  • [10] F. Zare ve J. A. Firouzjaee, “Hysteresis Band Current Control for a Single Phase Z-source Inverter with Symmetrical and Asymmetrical Z-network”, içinde 2007 Power Conversion Conference - Nagoya, Nagoya, Japan: IEEE, Nis. 2007, ss. 143-148. doi: 10.1109/PCCON.2007.372960.
  • [11] H. Zhang, Y. Liu, D. Sun, B. Ge, H. Abu-Rub, ve F. Z. Peng, “A hybrid modulation method for single-phase quasi-Z source inverter”, içinde 2014 IEEE Energy Conversion Congress and Exposition (ECCE), Pittsburgh, PA, USA: IEEE, Eyl. 2014, ss. 4444-4449. doi: 10.1109/ECCE.2014.6953729.
  • [12] S. DebBarman ve T. Roy, “Advanced Pulse Width Modulation technique for Z-Source Inverter”, içinde 2014 IEEE 6th India International Conference on Power Electronics (IICPE), Kurukshetra, India: IEEE, Ara. 2014, ss. 1-6. doi: 10.1109/IICPE.2014.7115850.
  • [13] K. Yu, J. Zhao, K. J. Tseng, F. L. Luo, ve M. Zhu, “Space vector pulse-width modulation for single-phase full-bridge Z-source inverter: SVPWM FOR SINGLE-PHASE ZSI”, Int. J. Circ. Theor. Appl., c. 43, sy 3, ss. 374-389, Mar. 2015, doi: 10.1002/cta.1946.
  • [14] U. Devaraj, S. Ramalingam, ve D. Sambasivam, “Evaluation of Modulation Strategies for Single-Phase Quasi-Z-Source Inverter”, J. Inst. Eng. India Ser. B, c. 100, sy 4, ss. 333-341, Ağu. 2019, doi: 10.1007/s40031-019-00378-z.
  • [15] I. Grgic, M. Bubalo, D. Vukadinovic, ve M. Basic, “Power Losses Analysis of a Three-phase Quasi-Z-Source Inverter”, içinde 2020 5th International Conference on Smart and Sustainable Technologies (SpliTech), Split, Croatia: IEEE, Eyl. 2020, ss. 1-5. doi: 10.23919/SpliTech49282.2020.9243732.
  • [16] Y. Zhou, L. Liu, ve H. Li, “A High-Performance Photovoltaic Module-Integrated Converter (MIC) Based on Cascaded Quasi-Z-Source Inverters (qZSI) Using eGaN FETs”, IEEE Trans. Power Electron., c. 28, sy 6, ss. 2727-2738, Haz. 2013, doi: 10.1109/TPEL.2012.2219556.
  • [17] R. Iijima, T. Isobe, ve H. Tadano, “Loss comparison of Z-source inverter from the perspective of short-through mode implementation and type of switching device”, içinde 2015 IEEE 2nd International Future Energy Electronics Conference (IFEEC), Taipei, Taiwan: IEEE, Kas. 2015, ss. 1-6. doi: 10.1109/IFEEC.2015.7361518.
  • [18] R. Iijima, T. Isobe, ve H. Tadano, “Loss analysis of Z-source inverter using SiC-MOSFET from the perspective of current path in the short-through mode”, içinde 2016 18th European Conference on Power Electronics and Applications (EPE’16 ECCE Europe), Karlsruhe: IEEE, Eyl. 2016, ss. 1-10. doi: 10.1109/EPE.2016.7695676.
  • [19] S. Kim, J. Park, K. Lee, ve T. Kim, “Novel Pulse-width Modulation Strategy to Minimize the Switching Losses of Z-Source Inverters”, Electric Power Components and Systems, c. 42, sy 11, ss. 1213-1225, Ağu. 2014, doi: 10.1080/15325008.2014.921955.
  • [20] A. Abdelhakim, P. Davari, F. Blaabjerg, ve P. Mattavelli, “Switching Loss Reduction in the Three-Phase Quasi-Z-Source Inverters Utilizing Modified Space Vector Modulation Strategies”, IEEE Trans. Power Electron., c. 33, sy 5, ss. 4045-4060, May. 2018, doi: 10.1109/TPEL.2017.2721402.
  • [21] I. Grgić, D. Vukadinović, M. Bašić, ve M. Bubalo, “Efficiency Boost of a Quasi-Z-Source Inverter: A Novel Shoot-Through Injection Method with Dead-Time”, Energies, c. 14, sy 14, s. 4216, Tem. 2021, doi: 10.3390/en14144216.
  • [22] S. Sonar, S. Mondal, J. Ghommam, ve S. Banerjee, “An Optimized Space Vector Based Switching Algorithm With Reduced Switching Transitions for Impedance Source Inverter”, IEEE Access, c. 10, ss. 28965-28974, 2022, doi: 10.1109/ACCESS.2022.3153497.
  • [23] M. Mohammadi, J. S. Moghani, ve J. Milimonfared, “A Novel Dual Switching Frequency Modulation for Z-Source and Quasi-Z-Source Inverters”, IEEE Trans. Ind. Electron., c. 65, sy 6, ss. 5167-5176, Haz. 2018, doi: 10.1109/TIE.2017.2784346.
  • [24] A. Abdelhakim, F. Blaabjerg, ve P. Mattavelli, “Single-Phase Quasi-Z-Source Inverters: Switching Loss Reduction Using a Quasi-Sinusoidal Modulation Strategy”, içinde 2019 IEEE Applied Power Electronics Conference and Exposition (APEC), Anaheim, CA, USA: IEEE, Mar. 2019, ss. 1918-1925. doi: 10.1109/APEC.2019.8721955.
  • [25] S. Radman, M. Shahnazari, ve H. Toodeji, “New switching strategy for single-phase multilevel quasi-Z-Source inverter”, içinde 2016 7th Power Electronics and Drive Systems Technologies Conference (PEDSTC), Tehran, Iran: IEEE, Şub. 2016, ss. 403-408. doi: 10.1109/PEDSTC.2016.7556895.
  • [26] I. Roasto, D. Vinnikov, J. Zakis, ve O. Husev, “New Shoot-Through Control Methods for qZSI-Based DC/DC Converters”, IEEE Trans. Ind. Inf., c. 9, sy 2, ss. 640-647, May. 2013, doi: 10.1109/TII.2012.2224353.
  • [27] I. Grgić, D. Vukadinović, M. Bašić, ve M. Bubalo, “Calculation of Semiconductor Power Losses of a Three-Phase Quasi-Z-Source Inverter”, Electronics, c. 9, sy 10, s. 1642, Eki. 2020, doi: 10.3390/electronics9101642. [28] D. W. Hart, “Chapter 8-Inverters”, Power Electronics. Ed. by Darlene M. Schueller. McGraw-Hill, ss. 357-358, 2010.
  • [29] Y. Liu, H. Abu-Rub, B. Ge, F. Blaabjerg, O. Ellabban, ve P. C. Loh, “Voltage-Fed Z-Source/Quasi-Z-Source Inverters”, içinde Impedance Source Power Electronic Converters, IEEE, 2016, ss. 20-34. Erişim: 09 Mart 2023. [Çevrimiçi]. Erişim adresi: https://ieeexplore.ieee.org/document/7572766
  • [30] Y. Liu, H. Abu‐Rub, B. Ge, F. Blaabjerg, O. Ellabban, ve P. C. Loh, Impedance Source Power Electronic Converters, 1. bs. Wiley, 2016. doi: 10.1002/9781119037088.
Toplam 29 adet kaynakça vardır.

Ayrıntılar

Birincil Dil Türkçe
Konular Elektrik Makineleri ve Sürücüler, Fotovoltaik Güç Sistemleri, Güç Elektroniği, Sayısal Tasarım, Yarı İletkenler
Bölüm Makaleler
Yazarlar

Halil İbrahim Aytekin 0000-0001-5650-4417

Selim Börekci 0000-0002-3140-4118

Erken Görünüm Tarihi 31 Aralık 2023
Yayımlanma Tarihi 31 Aralık 2023
Gönderilme Tarihi 23 Temmuz 2023
Yayımlandığı Sayı Yıl 2023

Kaynak Göster

IEEE H. İ. Aytekin ve S. Börekci, “Tek Fazlı Yarı-Empedans Kaynaklı İnverterlerin Anahtarlama Kaybını Azaltmak İçin Yeni Taşıyıcı Temelli Kontrol Stratejisi”, DÜMF MD, c. 14, sy. 4, ss. 571–580, 2023, doi: 10.24012/dumf.1331641.
DUJE tarafından yayınlanan tüm makaleler, Creative Commons Atıf 4.0 Uluslararası Lisansı ile lisanslanmıştır. Bu, orijinal eser ve kaynağın uygun şekilde belirtilmesi koşuluyla, herkesin eseri kopyalamasına, yeniden dağıtmasına, yeniden düzenlemesine, iletmesine ve uyarlamasına izin verir. 24456