A Modified Single-Phase Quasi-Z-Source AC-AC Converter

作者：Minh Khai Nguyen^*; Lim Young Cheol; Kim Yong Jae

来源：IEEE Transactions on Power Electronics, 2012, 27(1): 201-210.

DOI：10.1109/TPEL.2011.2157362

• Buck-boost capability
• pulsewidth modulation (PWM)
• quasi-Z-source converter
• reversing and maintaining phase angle
• safe-commutation
• single-phase ac-ac converter
• total harmonic distortion (THD)

A modified single-phase quasi-Z-source ac-ac converter is proposed in this paper. The proposed converter has the main features in that the output voltage can be bucked or boosted and be both in-phase and out-of-phase with the input voltage. The input voltage and output voltage share the same ground, the size of a converter is reduced, and it operates in a continuous current mode. A safe-commutation strategy for the modified single-phase quasi-Z-source ac-ac converter is used instead of a snubber circuit. The operating principles and a steady-state analysis are presented. A laboratory prototype, tested using a resistive load, a passive load, and a nonlinear load, was constructed that used an input voltage of 70 V-rms/60Hz in order to verify the performance of the modified single-phase quasi-Z-source ac-ac converter. The experimental results verified that the converter has a lower input current total harmonic distortion, a higher input power factor, and a higher efficiency in comparison to a conventional single-phase Z-source ac-ac converter. In addition, the experimental results show that the use of the safe-commutation strategy is a significant improvement, as it makes it possible to avoid voltage spikes on the switches.

• 出版日期2012-1