Methods for increasing energy harvest with PV module integrated power converters

Ehlmann, Jonathan

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https://hdl.handle.net/2142/46898 Copy

Description

Title

Methods for increasing energy harvest with PV module integrated power converters

Author(s)

Ehlmann, Jonathan

Issue Date

2014-01-16T18:25:42Z

Director of Research (if dissertation) or Advisor (if thesis)

Chapman, Patrick L.

Department of Study

Electrical & Computer Eng

Discipline

Electrical & Computer Engr

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

M.S.

Degree Level

Thesis

Keyword(s)

• Maximum power point tracking (MPPT)
• Alternating current photovoltaic (ACPV)
• Microinverter
• dc optimizer
• Photovoltaic (PV)
• Power Conversion
• Power Electronics
• Photovoltaic (PV) Submodule
• Photovoltaic (PV) SubMIC
• Module Integrated
• Solar
• Energy Harvest
• Global maximum power point tracking (MPPT)
• Local maximum power point tracking (MPPT)
• Distributed maximum power point tracking (MPPT)

Abstract

Increasing energy harvest from PV systems and reducing overall PV system costs are important to the continued adoption of solar energy. In an effort to achieve this, power converters are being integrated into PV modules. These power converters allow for more flexibility in PV system design by enabling each PV module to operate independently. The physical integration of these power converters creates new possibilities to improve the energy harvest. This thesis proposes methods and circuits that leverage this physical integration to further enhance PV module integrated power converters. A steady-state, SPICE-like, modified nodal analysis based (MNA) simulation tool is developed to study the effects of PV module mismatch and shading on PV systems. This simulation tool is used to calculate the power output of a PV system under varying conditions. This facilitates the comparisons of different algorithms and circuits for increasing energy harvest. Certain assumptions can be made when it is known that a power converter will only be operating on a single PV module, and extra voltage nodes are accessible when a power converter is physically integrated into a PV module. Two global maximum power point tracking (MPPT) algorithms are proposed that leverage this fact to improve energy harvest. Different circuit architectures are proposed to enable MPPT for a smaller subsection of PV cells called PV submodules. By tracking the MPP for PV submodules, further energy harvest improvements can be made. The proposed circuits include smaller power converters and multiple input converters for full PV submodule power processing as well as differential power processing (DPP) converters to handle the difference in power between PV submodules.

Graduation Semester

2013-12

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http://hdl.handle.net/2142/46898

Copyright and License Information

Copyright 2013 Jonathan Ehlmann

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