Asynchronous differential power processing for true maximum power point tracking of photovoltaic sub-modules

power electronics;distributed power electronics;photovoltaics;photovoltaic systems;solar energy;maximum power point trackers;differential power processing;DC-DC converters;buck-boost converters;wide-bandgap semiconductors

Hsiao, Felix Zephyr ; Pilawa-Podgurski ; Robert C. N.

关键词: power electronics;    distributed power electronics;    photovoltaics;    photovoltaic systems;    solar energy;    maximum power point trackers;    differential power processing;    DC-DC converters;    buck-boost converters;    wide-bandgap semiconductors;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/92676/HSIAO-THESIS-2016.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

This thesis examines maximum power point tracking (MPPT) at the photovoltaic (PV) sub-module level, but in the context of large arrays. Central communication carries large overheads, and neighbor-to-neighbor communication can have long propagation times in large arrays, so a communication-less solution was explored. An MPPT algorithm that could be run asynchronously was developed, and simulations confirmed its viability. Simulated tracking efficiencies of 99.977% and above were attained at steady-state.Next, a power electronics hardware prototype was designed to implement the MPPT algorithm. A differential power processing (DPP) architecture was used to achieve high system efficiencies. The efficiency of a single DPP converter reached a peak of 94.0%. In the laboratory tests performed, an increase in PV module power of up to 29.7% was observed using the proposed method when compared to no sub-module MPPT.Additionally, a long-term measurement system for a 12-module PV array was constructed. The system provided a safe, durable, and weatherproof mounting scheme for the power electronics and related circuitry. Furthermore, the setup allowed communication with the power electronics, so sub-module data could be collected and analyzed to determine the performance of the MPPT.Possible future work includes gathering more results, revising the circuit board, and simplifying the measurement system.