Simulation of Grid Connected Three-Level Neutral-Point-Clamped qZS Inverter using PSCAD

Open access


This paper is focused on a single-phase three-level neutral-point-clamped quasi-z-source inverter when it is operating being connected to the electrical grid. A control strategy for injecting current synchronized in phase with the voltage at the point of common coupling has been proposed and studied. It is achieved by means of controlling the output voltage between branches adjusting the output current by using a d-q frame and the analysis of the output filter. The control strategy generates the reference to be used in the modulation technique and it has been validated with and without shoot-through switching states. A method to calculate the minimum value of the shoot-through duty cycle is also explained in order to assure the proper control of the injected current when the input voltage is less than peak value of the grid voltage. It is an important feature because 3L-NPC qZSI due to its possibility of boosting input voltage in a single stage would operate better than a traditional inverter, for instance in photovoltaic applications when the value of irradiance is decreased. The presented results have been obtained using PSCAD/EMTDC as a simulation tool.

  • [1] F. Gao, P. C. Loh, F. Blaabjerg, D. M. Vilathgamuwa, “Dual Z-source inverter with three-level reduced common-mode switching”, IEEE Transactions on industry applications, vol.43, no. 6, pp.1597-1608, 2007.

  • [2] P. C. Loh, S. W. Lim, F. Gao, F. Blaabjerg, “Three-level Z-source inverters using a single LC impedance network”, IEEE Transactions on power electronics, vol. 22, no. 2, pp. 706-711, 2007.

  • [3] Anderson, J.; Peng, F.Z., "Four quasi-Z-Source inverters", in Proc. of IEEE Power Electronics Specialists Conference PESC’2008, pp. 2743- 2749, June 15-19, 2008.

  • [4] D. Vinnikov, I. Roasto, “Quasi-Z-Source-Based Isolated DC/DC Converters for Distributed Power Generation,” IEEE Trans. Ind. Electron., vol.58, no.1, pp.192-201, Jan. 2011.

  • [5] Dong Cao, Shuai Jiang, F. Z. Peng, “Low-Cost Semi-Z-source Inverter for Single-Phase Photovoltaic Systems,” IEEE Trans. Power Electron., vol. 26, no. 12, pp. 3514-3523, 2011.

  • [6] F. Li, B. Ge, D. Sun; D. Bi, F. Z Peng; A. R. Haitham, “Quasi-Z source inverter with battery based PV power generation system,” Electrical Machines and Systems (ICEMS), 2011 International Conference on , vol., no., pp.1-5, 20-23 Aug. 2011.

  • [7] Y. Li, J. Anderson, F. Z. Peng, D. Liu, “Quasi-Z-Source Inverter for Photovoltaic Power Generation Systems,” Applied Power Electronics Conference and Exposition, 2009. APEC 2009. Twenty-Fourth Annual IEEE , vol., no., pp.918-924, 15-19 Feb. 2009.

  • [8] J. Zakis, D. Vinnikov, “Study of Simple MPPT Converter Topologies for Grid Integration of Photovoltaic Systems,” Scientific Journal of RTU. 4. series., Enerģētika un elektrotehnika. - 29. vol. (2011), pp 67- 72.

  • [9] T. W. Chun, H. H. Lee, H. G. Kim, E. C. Nho, “Power Control for a PV Generation System Using a Single-Phase Grid-Connected Quasi ZSource Inverter,” IEEE Energy Conversion Congress & Exposition, 8th International Conference on Power Electronics - ECCE, pp. 889-893, May 30-June 3, 2011.

  • [10] J.H Park, H.G. Kim, E.C. Nho; T.W. Chun, “Capacitor voltage control for MPPT range expansion and efficiency improvement of gridconnected Quasi Z-Source Inverter,” Power Electronics Conference (IPEC), 2010 International , vol., no., pp.927-931, 21-24 June 2010.

  • [11] J. Liu; S. Jiang, D. Cao, Xi Lu, F. Z. Peng, “Sliding-mode control of quasi-Z-source inverter with battery for renewable energy system,” Energy Conversion Congress and Exposition (ECCE), 2011 IEEE , vol., no., pp.3665-3671, 17-22 Sept. 2011.

  • [12] Ott, S., Roasto, I., Vinnikov, D., Lehtla, T.: Analytical and Experimental Investigation of Neutral Point Clamped Quasi-Impedance-Source Inverter. Scientific Journal of Riga Technical University, Power and Electrical Engineering, vol.29, pp.113-118 (2011).

  • [13] Stepenko, S., Husev, O., Vinnikov, D., Ivanets, S.: FPGA Control of the Neutral Point Clamped Quasi-Z-Source Inverter. 13th Biennial Baltic Electronics Conference, pp.263-266 (2012).

  • [14] Husev, O., Roncero-Clemente, C., Stepenko, S., Vinnikov, D., Romero- Cadaval, E.: CCM Operation Analysis of the Single-Phase Three-Level Quasi-Z-Source Inverter. The 15th International Power Electronics and Motion Control Conference and Exposition EPE-PEMC 2012 ECCE Europe, pp.DS1b.21-1-DS1b.21-6 (2012).

  • [15] Roncero-Clemente, C., Romero-Cadaval, E., Husev, O., Vinnikov, D.: Simulation Study of Different Modulation Techniques for Three-Level Quasi-Z-Source Inverter. Scientific Journal of Riga Technical University, Power and Electrical Engineering. (2012).

  • [16] PSCAD/EMTDC User’s Guide. Manitoba HVDC Research Center, (2005).

  • [17] Oleksandr Husev, Sergey Stepenko, Carlos Roncero Clemente, Enrique Romero Cadaval, Dmitri Vinnikov. "Single Phase Three-Level Quasi- Z-Source Inverter With a New Boost Modulation Technique". 38th Annual Conference of the IEEE Industrial Electronics Society, IECON 2012. Conference Proceeding, pp. 5856- 5861. Montréal, Canada. October 2012.

Electrical, Control and Communication Engineering

The Journal of Riga Technical University

Journal Information


All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 28 28 28
PDF Downloads 6 6 6