A Review of Control Methods on Suppression of 2ω Ripple for Single-Phase Quasi-Z-Source Inverter

Abstract

One of the disadvantages of the charging systems and voltage regulation systems in alternative energy systems is that when the direct current (DC)/alternative current (AC) or AC/DC conversion is made from the energy source, the energy flow at 2ω frequency between the direct current side and the alternative current side causes ripples in the DC, inductors, and capacitors. The ripples that occur in 2ω frequency increase the harmonic distortion and reduce the efficiency in the photovoltaic energy system. For addressing this problem, different control methods are evaluated in this paper for the elimination of ripples that occur at 2ω frequency, both on the perspective of DC control side and AC control side with a thorough comparative analysis with existing results in the literature. In the present study, the model of Single-Phase Quasi-Z Source (QZS) inverter and closed-loop control methods of the inverter are examined and compared with pulse width modulation (PWM) methods. In addition, the control methods are used to eliminate the ripples at 2ω frequency in the use of inverters, and the advantages and disadvantages of these methods are presented. INDEX TERMS QZS inverter, suppression of 2ω ripple, control methods, pulse width modulation. I. INTRODUCTION

Design and implementation of a Quasi-Z-Source inverter

“…QZSI devresinin kısa devre çalışabilmesi nedeniyle kondansatör ve bobin değerlerinin seçimi verimi doğrudan etkilemektedir. Literatürde yapılan çalışmalarda; bobindeki akım dalgalanmasının ortalama değerin %10'un altında, kondansatördeki gerilim dalgalanmasının ise ortalama değerin %3'ün altında olduğu kabullerin esas alındığı görülmektedir [11]- [12].…”

Review of impedance source power converter for electrical applications

“…Model of single phase QZS inverter and closed-loop control methods of the inverter are examined and compared with PWM methods. These control methods are used to eliminate the ripples at 2ω frequency in the inverters, and the advantages and disadvantages of these methods are presented [71].…”

Control Strategies and Power Decoupling Topologies to Mitigate 2ω-Ripple in Single-Phase Inverters: A Review and Open Challenges

“…These topologies still have a challenge of accidental short-circuiting of the switches in the same leg(s) of the inverter [61]. The impedancesource inverters (ISIs) [47]- [49] are the good choice in such limitations and operating conditions. However, these topologies require large size impedance-source network to filter low-frequency 2ω−ripple [62]- [64].…”

“…Flow chart of classification of 2ω−ripple mitigation techniques Passive power decoupling techniques (a) Isolated Voltage source inverter[36] (b) Grid-tied-Voltage source converter[39] (c) Flyback-type center-tapped inverter[42] (d) Inverter with front-end dual-bridge converter with high-frequency DC-link[43](e) Transformer-less buck and boost inverter topology[44](f) Pulse-link DC-AC converter[45] (g) two-stage DC-DC-AC converter (having a front-end buck or boost or buck-boost DC-DC converter)[46] (h) Z-source inverter (i) quasi-Z source inverter (j) quasi-switched boost inverter (k) Three-level single-phase impedance source inverter(Fig. 5(h-k)[47]-[49]). …”