TY - JOUR
T1 - Front-End Isolated Quasi-Z-Source DC-DC Converter Modules in Series for High-Power Photovoltaic Systems-Part I
T2 - Configuration, Operation, and Evaluation
AU - Liu, Yushan
AU - Abu-Rub, Haitham
AU - Ge, Baoming
N1 - Publisher Copyright:
© 1982-2012 IEEE.
PY - 2017/1
Y1 - 2017/1
N2 - A quasi-Z-source modular cascaded converter (qZS-MCC) is proposed for dc integration of high-power photovoltaic (PV) systems. The qZS-MCC comprises series-connected front-end isolated qZS half-bridge (HB) dc-dc converter submodules (SMs). With the front-end isolation, the qZS-MCC achieves high-voltage dc capability, while maintaining modularity and PV panel grounded. The post-stage qZS-HB handles the PV voltage and power flows, dc-link voltage balance, and output-series power integration. Whereas, the front-end isolation converters of all SMs perform a constant duty cycle, lowing the control complexity. There is no double-line-frequency power flowing through the dc-side PV panels, qZS inductors, and qZS capacitors in the qZS-MCC, so small qZS impedance is possible compared to the existing qZS cascaded multilevel inverter. The configuration, operating principle, power loss evaluation, and passive components design of the proposed system are investigated in this part of the paper. The system control, modeling, and corresponding verifications are stated in Part II of this paper.
AB - A quasi-Z-source modular cascaded converter (qZS-MCC) is proposed for dc integration of high-power photovoltaic (PV) systems. The qZS-MCC comprises series-connected front-end isolated qZS half-bridge (HB) dc-dc converter submodules (SMs). With the front-end isolation, the qZS-MCC achieves high-voltage dc capability, while maintaining modularity and PV panel grounded. The post-stage qZS-HB handles the PV voltage and power flows, dc-link voltage balance, and output-series power integration. Whereas, the front-end isolation converters of all SMs perform a constant duty cycle, lowing the control complexity. There is no double-line-frequency power flowing through the dc-side PV panels, qZS inductors, and qZS capacitors in the qZS-MCC, so small qZS impedance is possible compared to the existing qZS cascaded multilevel inverter. The configuration, operating principle, power loss evaluation, and passive components design of the proposed system are investigated in this part of the paper. The system control, modeling, and corresponding verifications are stated in Part II of this paper.
KW - DC-DC power conversion
KW - galvanic isolation
KW - photovoltaic power system
KW - quasi-Z-source converter
UR - http://www.scopus.com/inward/record.url?scp=85006835226&partnerID=8YFLogxK
U2 - 10.1109/TIE.2016.2598673
DO - 10.1109/TIE.2016.2598673
M3 - Article
AN - SCOPUS:85006835226
SN - 0278-0046
VL - 64
SP - 347
EP - 358
JO - IEEE Transactions on Industrial Electronics
JF - IEEE Transactions on Industrial Electronics
IS - 1
M1 - 7539365
ER -