Title |
A Quasi Z-Source AC-AC Converter with a Low DC Voltage Distribution Capability Operating as a Power Electronic Transformer |
Authors |
류대현(Yoo, Dae-Hyun) ; 엄준현(Oum, Jun-Hyun) ; 정영국(Jung, Young-Gook) ; 임영철(Lim, Young-Cheol) |
DOI |
https://doi.org/10.5370/KIEE.2014.63.3.358 |
Keywords |
Power electronic transformer ; A quasi Z-source AC-AC converter ; Low DC voltage distribution capability ; In phase buck-boost AC voltage mode ; Constant DC voltage PI control |
Abstract |
This paper proposes a quasi Z-source AC-AC converter with the low DC voltage distribution capability operating as a power electronic transformer. The proposed system has configuration that the input terminals of two quasi Z-source AC-AC converters are connected in parallel, also their output terminal are connected in series. Simple control method of duty ratio was proposed for the in phase buck-boost AC voltage mode and the DC output voltage control. DSP based experiment and PSIM simulation were performed. As a result, the PSIM simulation results were same with the measured results. By controlling the duty ratio under the condition of 100 [{Ω}] load, quasi Z-source AC-AC converter could buck and boost the AC output voltage in phase with the AC input voltage, and the same time, the constant DC voltage could be output without affecting the AC output characteristics. And, the DC output voltage 48[V] was constantly controlled in dynamic state in case while the load is suddenly changed (50[Ω]{ rightarrow}100[Ω]). From the above result, we could know that the quasi Z-source AC-AC converter can act as a power electronic transformer with a low DC voltage distribution capability. |