Control of Quasi-Z Source Inverter with Super Capacitor under Unbalanced Grid Fault Conditions


Article Preview

The quasi-Z-source inverter (qZSI) has some unique advantages and is suitable for renewable energy sources such as solar and wind generation system. In order to make the inverter have the ride-through ability and the current into the grid symmetrical when unbalanced grid faults occur, the topology of qZSI with super capacitor substituting the low voltage capacitor and the unbalance control strategy were proposed. With a super capacitor the system can balance and smooth the power between the generation unit and grid, also the current injected into the grid can be symmetrical through the unbalance control method. The circuit of the new topology and the mathematical model of the three-phase converter under grid voltage unbalance conditions have been analyzed. And then, closed-loop control scheme for the proposed system is used to control the power flow of generation unit, grid and super capacitor in this system, also unbalance control strategies in positive (dq) + and negative (dq) – reference frames have been implemented in the grid-connected qZSI system to make the current into the grid symmetrical during the grid fault. The operating mode during unbalanced grid fault is simulated in MATLAB/Simulink, and the simulation results are presented to verify the theoretical analysis and the control scheme.



Edited by:

Xiaochun Tang, Xiaohong Chen, Yuxiang Dong, Xiuguo Wei and Qingsheng Yang




F. L. Li et al., "Control of Quasi-Z Source Inverter with Super Capacitor under Unbalanced Grid Fault Conditions", Applied Mechanics and Materials, Vols. 291-294, pp. 2124-2131, 2013

Online since:

February 2013




[1] Y. Huang, M.S. Shen, F.Z. Peng etc. In: IEEE Trans on Power Electron; 2006, 21(6), pp.1776-1782.

[2] R. Badin, Y. Huang, F.Z. Peng etc. Grid Inter connected Z-Source PV System. In: Proceedings of IEEE power electronics specialists conference. Orlando, USA; 2007, pp.2328-2333.


[3] Y. Li, J. Anderson, F.Z. Peng etc. Quasi-Z-source inverter for photovoltaic power generation systems. In: Proceedings of the twenty-fourth Annual IEEE applied power electronics conference and exposition. Washington DC, USA; 2009, pp.918-924.


[4] Baoming Ge, Qin Lei, F.Z. Peng etc. An Effective PV Power Generation Control System usingQuasi-Z Source Inverter with Battery. In: Energy Conversion Congress and Exposition (ECCE), 2011 IEEE, p.1044 – 1050.


[5] Liu Yushan, Baoming Ge, F.Z. Peng etc. Quasi-Z-Source Inverter based PMSG Wind Power Generation System. In: Energy Conversion Congress and Exposition (ECCE), 2012 IEEE, p.291 – 297.


[6] M. Ahsanul Alam, A.H.M.A. Rahim, M.A. Abido. Super capacitor based energy storage system for effective fault ride through of wind generation system. In: Industrial Electronics (ISIE), 2010 IEEE International Symposium, p.2481 – 2486.


[7] Xiaoyu Wang, Meng Yue, Eduard Muljadi. Modeling and control system design for an integrated solar generation and energy storage system with a ride-through capability. In: Energy Conversion Congress and Exposition (ECCE), 2012 IEEE, pp.3727-3734.


[8] J. Hu, Y. He. In: IEEE Trans on Energy Conversion; 2008, 23(3), p.903–913.

Fetching data from Crossref.
This may take some time to load.