Solar Grid-Tied Inverter, with Battery Back-up, for Efficient Solar Energy Harvesting

ABSTRACT:

Solar Grid-Tied Inverter system is an electricity generating system that is connected to the utility grid. This paper discusses the design of a Grid-Tied Inverter (GTI). The first stage is Maximum Power Point Tracking (MPPT) which is implemented using perturb and observe algorithm. Then push pull converter is used to convert DC output from MPPT stage to 330V dc. This DC voltage is then converted into AC voltage using full-wave inverter topology employing unipolar SPWM technique. Then synchronization is achieved between grid and photovoltaic system. Finally, power flow control mechanism controls the power flow from GTI system to the grid and the house load.

KEYWORDS:

  1. Grid-tied inverter
  2. SPWM
  3. Power flow
  4. MPPT

SOFTWARE: MATLAB/SIMULINK

CIRCUIT DIAGRAM:

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Figure 1. Cuk converter.

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Figure 2. Full wave inverter topology .

EXPECTED SIMULATION RESULTS:

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Figure 3. Inverter output before filter

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Figure 4. Inverter output after filter.

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Figure 5. Simulink circuit to demonstrate power flow.

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Figure 6. GTI output power.

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Figure 7. Grid output power.

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Figure 8. Power through inductor.

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Figure 9. GTI output power.

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Figure 10. Grid output power.

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Figure 11. Power through inductor.

REFERENCES:

[1] Power Electronics: Circuits, Devices and Applications, 3/E by M. H. Rashid, Prentice Hall, 2004J. Clerk Maxwell, A Treatise on Electricity and Magnetism, 3rd ed., vol. 2. Oxford: Clarendon, 1892, pp.68–73.

[2] Electric Machinery Fundamentals by Stephen J. Chapman, 4th Edition, McGraw-Hill, 2005K. Elissa, “Title of paper if known,” unpublished.

[3] M. A. Salam, Fundamentals of Power Systems, Alpha Science Oxford, UK International Ltd., 2009.

[4] T. Kwang and S. Masri, “Grid Tie Photovoltaic Inverter for Residential Application,” Modern Applied Science, vol. 5, No. 4, Aug. 2011, pp. 3-4, doi:10.5539/mas.v5n4p200