Constant Boost Control with Third Harmonic Injection for Quasi-Z Source Inverter used in PV Grid-connected System

Compared to the dual-stage inverter, quasi-Z-source inverter (qZSI) offers higher reliability and lower switch count but suffers from higher voltage stress on components. The qZSI is normally controlled by the simple boost control (SBC) method that adds reference signals to the sinusoidal PWM to generate the shoot-through state. This paper develops a constant boost control method with third harmonic injection. Compared to the SBC, the proposed control method increases the voltage boost and reduces the voltage stress on switches and passive components of the qZSI, making it suitable for PV grid-connected applications. The third harmonic signal is produced and injected in a way that keeps it in phase with the reference sinusoidal signals, regardless of the solar irradiance level. This reduces the total harmonic distortions (THD) and improves the output power quality. Simulation results are presented for validation of the theoretical analysis and controller design.

[1]  F.Z. Peng,et al.  Comparison of Traditional Inverters and $Z$ -Source Inverter for Fuel Cell Vehicles , 2004, IEEE Transactions on Power Electronics.

[2]  F.Z. Peng,et al.  Four quasi-Z-Source inverters , 2008, 2008 IEEE Power Electronics Specialists Conference.

[3]  Wei Qian,et al.  Trans-Z-Source Inverters , 2011 .

[4]  Zhaoming Qian,et al.  Current-Fed Quasi-Z-Source Inverter With Voltage Buck–Boost and Regeneration Capability , 2011 .

[5]  Joel Anderson,et al.  A Class of Quasi-Z-Source Inverters , 2008, 2008 IEEE Industry Applications Society Annual Meeting.

[6]  Zuo Zhi-peng Switched-inductor Quasi-Z-source Inverter , 2012 .

[7]  Yuan Li,et al.  Modeling and Control of Quasi-Z-Source Inverter for Distributed Generation Applications , 2013, IEEE Transactions on Industrial Electronics.

[8]  F.Z. Peng,et al.  Maximum boost control of the Z-source inverter , 2004, 2004 IEEE 35th Annual Power Electronics Specialists Conference (IEEE Cat. No.04CH37551).

[9]  Heung-Geun Kim,et al.  Switched-Coupled-Inductor Quasi-Z-Source Inverter , 2016, IEEE Transactions on Power Electronics.

[10]  Mohsen Hamzeh,et al.  Maximum constant boost approach for controlling quasi-Z-source-based interlinking converters in hybrid AC–DC microgrids , 2016 .

[11]  Jin Wang,et al.  Constant boost control of the Z-source inverter to minimize current ripple and voltage stress , 2006, IEEE Transactions on Industry Applications.

[12]  Heung-Geun Kim,et al.  Grid-connected PV System Using a Quasi-Z-source Inverter , 2009, 2009 Twenty-Fourth Annual IEEE Applied Power Electronics Conference and Exposition.

[13]  Fang Zheng Peng Z-source inverter , 2002 .

[14]  Wei Qian,et al.  Trans-Z-Source Inverters , 2010, IEEE Transactions on Power Electronics.

[15]  Yuan Li,et al.  AC small signal modeling, analysis and control of quasi-Z-Source Converter , 2012, Proceedings of The 7th International Power Electronics and Motion Control Conference.

[16]  Zheng Jianyong,et al.  Novel Switched-Inductor Quasi-Z-source Inverter , 2014 .