Design of a Discontinuous SVPWM Strategy-Based Current Controller in DQ Synchronous Frame for the Grid-Connected 3L-T-Type Inverter
Received: 22 July 2025 | Revised: 10 September 2025 | Accepted: 18 September 2025 | Online: 9 October 2025
Corresponding author: Worawat Sa-ngiamvibool
Abstract
This study proposes an innovative discontinuous Space Vector Pulse Width Modulation (SVPWM) technique integrated with a DQ-based current control scheme for a three-level T-type (3L-T-Type) inverter running in grid-connected mode. The discontinuous modulation technique employs the Nearest Three Vectors (NTVs) from the space vector diagram to provide appropriate switching signals, which substantially decreases the commutation of the Controllable Power Switches (CPSs), thus reducing switching losses. To enhance the output power quality prior to grid injection, a transformation from standard DQ current control to active and reactive Power Control (PQ) is implemented. The proposed method allows for separate control of the d-axis and q-axis components while keeping them in sync with the grid voltage. A mathematical model was developed to compute the stay time of each switching state across different regions and sectors, facilitating the generation of discontinuous modulation waves for each phase leg. The simulation results in MATLAB/Simulink demonstrate improved performance with a 33% reduction in switching commutations, a Total Harmonic Distortion (THD) of 4.67% for the current, proper alignment with the grid voltage at the main frequency of 50 Hz, and effective balancing of the DC-link voltage. These findings confirm the proposed controller's efficacy and its appropriateness for high-performance grid-connected applications, including renewable energy integration and electric vehicle infrastructure.
Keywords:
3L-T-Type inverter, SVPWM, DQ control, grid-connected inverter, harmonic distortionDownloads
References
R. Mahalakshmi and K. C. S. Thampatty, "Grid Connected Multilevel Inverter for Renewable Energy Applications," Procedia Technology, vol. 21, pp. 636–642, Jan. 2015. DOI: https://doi.org/10.1016/j.protcy.2015.10.076
E. O’Shaughnessy, D. Cutler, K. Ardani, and R. Margolis, "Solar plus: A review of the end-user economics of solar PV integration with storage and load control in residential buildings," Applied Energy, vol. 228, pp. 2165–2175, Oct. 2018. DOI: https://doi.org/10.1016/j.apenergy.2018.07.048
M. Salem, A. Richelli, K. Yahya, M. N. Hamidi, T.-Z. Ang, and I. Alhamrouni, "A Comprehensive Review on Multilevel Inverters for Grid-Tied System Applications," Energies, vol. 15, no. 17, Jan. 2022, Art. no. 6315. DOI: https://doi.org/10.3390/en15176315
K. Zeb et al., "A comprehensive review on inverter topologies and control strategies for grid connected photovoltaic system," Renewable and Sustainable Energy Reviews, vol. 94, pp. 1120–1141, Oct. 2018. DOI: https://doi.org/10.1016/j.rser.2018.06.053
A. Sinha, K. Chandra Jana, and M. Kumar Das, "An inclusive review on different multi-level inverter topologies, their modulation and control strategies for a grid connected photo-voltaic system," Solar Energy, vol. 170, pp. 633–657, Aug. 2018. DOI: https://doi.org/10.1016/j.solener.2018.06.001
M. Shruthi, G. Ezhilarasan, and S. M. Chandra Shekar, "Advanced SVPWM Technique for Multilevel Inverter Systems," Engineering, Technology & Applied Science Research, vol. 15, no. 3, pp. 23923–23929, Jun. 2025. DOI: https://doi.org/10.48084/etasr.11078
A. Bughneda, M. Salem, A. Richelli, D. Ishak, and S. Alatai, "Review of Multilevel Inverters for PV Energy System Applications," Energies, vol. 14, no. 6, Jan. 2021, Art. no. 1585. DOI: https://doi.org/10.3390/en14061585
S. Daher, J. Schmid, and F. L. M. Antunes, "Multilevel Inverter Topologies for Stand-Alone PV Systems," IEEE Transactions on Industrial Electronics, vol. 55, no. 7, pp. 2703–2712, Jul. 2008. DOI: https://doi.org/10.1109/TIE.2008.922601
M. Schweizer and J. W. Kolar, "Design and Implementation of a Highly Efficient Three-Level T-Type Converter for Low-Voltage Applications," IEEE Transactions on Power Electronics, vol. 28, no. 2, pp. 899–907, Feb. 2013. DOI: https://doi.org/10.1109/TPEL.2012.2203151
K. Lee, H. Shin, and J. Choi, "Comparative analysis of power losses for 3-Level NPC and T-type inverter modules," in 2015 IEEE International Telecommunications Energy Conference (IN℡EC), Osaka, Japan, Oct. 2015, pp. 1–6. DOI: https://doi.org/10.1109/INTLEC.2015.7572357
M. Y. Ali Khan, H. Liu, Z. Yang, and X. Yuan, "A Comprehensive Review on Grid Connected Photovoltaic Inverters, Their Modulation Techniques, and Control Strategies," Energies, vol. 13, no. 16, Jan. 2020, Art. no. 4185. DOI: https://doi.org/10.3390/en13164185
P. Ramasamy and V. Krishnasamy, "SVPWM control strategy for a three phase five level dual inverter fed open-end winding induction motor," ISA Transactions, vol. 102, pp. 105–116, Jul. 2020. DOI: https://doi.org/10.1016/j.isatra.2020.02.034
Y. Bekakra and D. Ben Attous, "Comparison Study Between SVM and PWM Inverter in Sliding Mode Control of Active and Reactive Power Control of a DFIG for Variable Speed Wind Energy," International Journal of Renewable Energy Research, vol. 2, no. 3, pp. 471–477, Sep. 2012.
Q. Yan et al., "Optimization of the Symmetrical SVPWM for Three-Level T-Type Inverters With Unbalanced and Oscillated Neutral-Point Voltages," IEEE Transactions on Industrial Electronics, vol. 71, no. 4, pp. 4026–4037, Apr. 2024. DOI: https://doi.org/10.1109/TIE.2023.3279521
D. A. Tuan, P. Vu, and N. V. Lien, "Design and Control of a Three-Phase T-Type Inverter using Reverse-Blocking IGBTs," Engineering, Technology & Applied Science Research, vol. 11, no. 1, pp. 6614–6619, Feb. 2021. DOI: https://doi.org/10.48084/etasr.3954
D. Chen, Y. Sun, G. Zhao, and W. Zhao, "Improved Synchronous Space Vector Pulse Width Modulation Strategy for Three-Level With Common-Mode Voltage Suppression," IEEE Access, vol. 12, pp. 27578–27595, 2024. DOI: https://doi.org/10.1109/ACCESS.2024.3363178
S. Y. Kim, S. G. Song, and S. J. Park, "Minimum Loss Discontinuous Pulse-Width Modulation Per Phase Method for Three-Phase Four-Leg Inverter," IEEE Access, vol. 8, pp. 122923–122936, 2020. DOI: https://doi.org/10.1109/ACCESS.2020.3006245
K. Kang, Q. Wang, and J. Meng, "Vector Control of Three-Phase Solar Farm Converters Based on Fictive-Axis Emulation," Journal of Computer Science Research, vol. 2, no. 3, pp. 10–13, Aug. 2020. DOI: https://doi.org/10.30564/jcsr.v2i3.2117
Downloads
How to Cite
License
Copyright (c) 2025 Kanyarat Ek-Iam, Chonlatee Photong, Niwat Angkawisittpan, Ongard Tubburee, Sitthisak Audomsi, Worawat Sa-ngiamvibool
This work is licensed under a Creative Commons Attribution 4.0 International License.
Authors who publish with this journal agree to the following terms:
- Authors retain the copyright and grant the journal the right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) after its publication in ETASR with an acknowledgement of its initial publication in this journal.
