design and implementation of transformerless inverter with dc current elimination
DESCRIPTION
DESIGN AND IMPLEMENTATION OF TRANSFORMERLESS INVERTER WITH DC CURRENT ELIMINATION. Guided By Dr. Sasidharan Sreedharan. Presented By, SUDHIN P.K PGEE02012. CONTENTS. OBJECTIVE MOTIVATION LITERATURE REVIEW PROPOSED CONVERTER COMPLETE MODEL – BLOCK DIAGRAM EXPECTED OUTCOME GANTT CHART - PowerPoint PPT PresentationTRANSCRIPT
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DESIGN AND IMPLEMENTATION OF TRANSFORMERLESS INVERTER WITH DC CURRENT ELIMINATION
Presented By,SUDHIN P.KPGEE02012
Guided By Dr. Sasidharan Sreedharan
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CONTENTS OBJECTIVE MOTIVATION LITERATURE REVIEW PROPOSED CONVERTER COMPLETE MODEL – BLOCK DIAGRAM EXPECTED OUTCOME GANTT CHART REFERENCES
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OBJECTIVE Phase I :
i. Simulation : Transformerless Inverter Modelii. Hardware implementation of Transformerless
inverter (Off Grid Model)
Phase II :i. PLL Designii. Grid Integration of Developed Model
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MOTIVATION
Increasing demand of PV system Development of Cost Effective system Complete elimination of CM leakage current
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WHY ‘LESS’ TOPOLOGY? Most Commercial PV inverters employ either
line-frequency or high-frequency isolation transformers.
Increases – Size,Cost,Losses Transformerless Topology – Reduced Size,
weight, cost and installation complexity Increases efficiency by 2% produces Common Mode Leakage Current
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THE COMMON MODE LEAKAGE CURRENT,
increases the system losses reduces the grid connected current quality induces severe conducted and radiated
electromagnetic interference causes personal safety problems.
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Full H Bridge Topology [5] Half H Bridge Topology [5]
I. Simple Structure
II. High EMI
III. High Common mode Leakage Current
I. Simple Structure
II. High EMI
III. High Common mode Leakage Current
IV. High Voltage Stress across switches
Literature Review
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HERIC Topology [6] H5 Topology [7]
I. Large number of Switches
II. Low EMI
III. Low Common mode Leakage Current
I. Less number of Switches
II. Low EMI
III. Low Common mode Leakage Current
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PROPOSED TOPOLOGY : CONCEPT
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PROPOSED TOPOLOGY
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COMPARISON WITH PATENTED TOPOLOGIES
HERIC(Sunways)
H5 Topology(SMA)
Proposed Topology
Input Capacitors 1 1
1 (but one additional switched capacitor)
Input Capacitance low low low
Switches 6 5 5Diodes 2 0 0
No of output voltage Levels
3 3 3
Leakage Current Very Low Very Low Nil
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COMPLETE MODEL
DC-DCCONVERTER(MPPT)
TRANSFORMER-LESS INVERTER
LOAD/GRID
MICRO CONTROLLER
MICROCONTROLLER
12/24 V(DC)
400 V(DC)
220 V(AC)
Vpv,Ipv
TriggeringPulses
TriggeringPulses (SPWM)
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EXPECTED OUTCOME Simulation and Hardware implementation of
Transformerless Inverter with complete DC current elimination.
Less voltage and current stress on switches in comparison with HERIC and H5 Topology
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GANTT CHART
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REFERENCES
[1] Gu, Yunjie, Wuhua Li, Yi Zhao, Bo Yang, Chushan Li, and Xiangning He.
"Transformerless Inverter with Virtual DC Bus Concept for Cost Effective Grid-connected
PV Power Systems." (2013): 1-1.
[2] S. B. Kjaer, J. K. Pedersen, and F. Blaabjerg, “A review of single-phase grid-connected
inverters for photovoltaic modules,” IEEE Trans. Ind.Appl., vol. 41, no. 5, pp. 1292–1306,
Sep./Oct. 2005.
[3] T. Kerekes, R. Teodorescu, P. Rodr´ıguez, G. V´azquez, and E. Aldabas, “A new high-
efficiency single-phase transformerless PV inverter topology,”IEEE Trans. Ind. Electron.,
vol. 58, no. 1, pp. 184–191, Jan. 2011.
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REFERENCES[4] Yang, Bo, Wuhua Li, Yunjie Gu, Wenfeng Cui, and Xiangning He. "Improved
transformerless inverter with common-mode leakage current elimination for a
photovoltaic grid-connected power system." Power Electronics, IEEE Transactions
on 27, no. 2 (2012): 752-762.
[5] Patrao, Iván, Emilio Figueres, Fran González-Espín, and Gabriel Garcerá.
"Transformerless topologies for grid-connected single-phase photovoltaic
inverters." Renewable and Sustainable Energy Reviews 15, no. 7 (2011): 3423-3431.
[6] S. Heribert, S. Christoph, and K. Juergen, German Patent HERIC Topology,DE 10221592 A1, Apr. 2003.[7] V. Matthias, G. Frank, B. Sven, and H. Uwe, German Patent H5-Topology,DE 102004030912 B3, Jan. 2006.