Non-Isolated High Gain Bidirectional Modular DC-DC Converter with Unipolar and Bipolar Structure for DC Networks Interconnections

다국어 초록 (Multilingual Abstract)

In this paper, a novel high gain bidirectional modular dc-dc converter (BMC) with unipolar and bipolar structures for dc network interconnections is proposed. When compared with traditional dc grid-connecting converters, the proposed converter can achieve a high voltage gain with a simple modular transformerless structure. A sub-modular structure for the BMC is proposed to eliminate the unbalanced current stress between the different power units (levels) in the BMC. This can realize current sharing and standardized production and assembling. In addition, phase-interval operation is introduced to the sub-modules to realize low voltage and current ripple in both sides of the converter. Furthermore, two types of bipolar topologies of the sub-modular BMC were proposed to extend its application in bipolar dc network connections. In addition, the control system was optimized for grid-connection applications by providing various control strategies. Finally, simulations of a 3-level unipolar sub-modular BMC and a 4-level bipolar sub-modular BMC were conducted, and a 1-kW experimental 3-level unipolar prototype was developed to verify the effectiveness of the proposed converter.

목차 (Table of Contents)

• Abstract
• I. INTRODUCTION
• II. OPERATION PRINCIPLE OF THE UNIPOLAR BMC
• III. SUB-MODULARIZATION OF UNIPOLAR BMC
• IV. TWO TYPES OF BIPOLAR BMCS
• V. CONTROL SYSTEM
• VI. SIMULATION RESULTS
• VII. EXPERIMENTAL RESULTS
• VIII. CONCLUSIONS
• REFERENCES

참고문헌 (Reference)

1 S. L Undberg, "Wind farm configuration and energy efficiency studies - Series dc versus ac layouts" Chalmers University of Technology 2006

2 L. Po-Wa, "Steady-state analysis of an interleaved boost converter with coupled inductors" 47 (47): 787-795, 2000

3 F. H. Khan, "Start-up and dynamic modeling of the multilevel modular capacitor-clamped converter" 25 (25): 519-531, 2010

4 T. Ishii, "Power factor correction using interleaving technique for critical mode switching converters" 905-910, 1998

5 S. Vighetti, "Optimization and design of a cascaded DC/DC converter devoted to grid-connected photovoltaic systems" 27 (27): 2018-2027, 2012

6 D. Cao, "Optimal design of a multilevel modular capacitor-clampled DC-DC converter" 28 (28): 3816-3826, 2013

7 R. Kadri, "Nondissipative string current diverter for solving the cascaded DC–DC converter connection problem in photovoltaic power generation system" 27 (27): 1249-1258, 2012

8 F. H. Khan, "Multiple-load-source integration in a multilevel modular capacitor-clamped DC-DC converter featuring fault tolerant capability" 24 (24): 14-24, 2009

9 F. S. Garcia, "Modeling and control design of the interleaved double dual boost converter" 60 (60): 1292-1300, 2013

10 D. Vinnikov, "Middle-frequency isolation transformer design issues for the high-voltage DC/DC converter" 1930-1936, 2008

11 C. Meyer, "Key components f or future offshore dc grids;Inst. Power Generation and Storage Systems" R W TH Aachen University 2007

12 T. Nouri, "Interleaved high step-up dc-dc converter based on three-winding high-frequency coupled inductor and voltage multiplier cell" 8 (8): 175-189, 2015

13 M. S. Elmore, "Input current ripple cancellation in synchronized, parallel connected critically continuous boost converters" 152-158, 1996

14 C. H. Chan, "Input current analysis of interleaved boost converters operating in discontinuous-inductor current mode" 392-398, 1997

15 F. H. Khan, "Hybird electric vehicle power management solutions based on isolated and nonisolated configurations of multilevel modular capacitor-clamped converter" 56 (56): 3079-3095, 2009

16 N. Genc, "DSP-based current sharing of average current controlled two-cell interleaved boost PFC converter" 4 (4): 1015-1022, 2011

17 Z. Chen, "A soft switching full bridge converter with reduced parasitic oscillation in a wide load range" 29 (29): 801-812, 2014

18 L. Sun, "A non-isolated bidirectional soft-switching power-unit-based DC-DC converter with unipolar and bipolar structure for DC networks interconnection" 54 (54): 2677-2689, 2018

19 G. J. Kish, "A modular multilevel DC/DC converter with fault blocking capability for HVDC interconnects" 30 (30): 148-162, 2015

20 X. Hu, "A high voltage gain dc-dc converter integrating coupled-inductor and diode-capacitor techniques" 29 (29): 789-800, 2014

21 K. C. Tseng, "A high step-up converter with a voltage multiplier module for a photovoltaic system" 28 (28): 3047-3057, 2013

22 Y. Ye, "A high step-up PWM DC-DC converter with coupled-inductor and resonant switched-capacitor" 32 (32): 7739-7749, 2016

23 L. Huber, "A design approach for server power supplies for networking applications" 1163-1169, 2000

24 L. Huber, "A design approach for server power supplies for networking applications" 1163-1169, 2000