Development of a DC Optimizer Using a Two-Switch Flyback Converter with Partial Power Conversion

Main Article Content

Chokchai Chuenwattanapraniti
Montana Rungsiyopas

Abstract

This article presents the development of a DC Optimizer designed for installation on solar cell modules to solve the problem of power reduction caused by module mismatch under series-connected string configurations. The approach applies to a two-switch flyback converter structure combined with the Partial Power Conversion technique, which processes only the power difference rather than the total generated power. As a result, the proposed optimizer achieves high efficiency while significantly reducing the size of the power circuit. The appropriate design guidelines for the power circuit, system modeling, and control system design are presented. The optimizer prototype was tested under various operating conditions. The results indicated that at an input-to-output voltage ratio ranging from 0.55 to 0.75, the power processed through the flyback circuit accounted for only 30-50% of the total power generated by the PV module, while the remainder was transferred directly to the output. Consequently, the overall system efficiency increased by 12-15% compared to the converter's efficiency, maintaining the ability to accurately track the maximum power point of the photovoltaic modules.

Article Details

How to Cite
[1]
C. Chuenwattanapraniti and M. Rungsiyopas, “Development of a DC Optimizer Using a Two-Switch Flyback Converter with Partial Power Conversion”, UTK RESEARCH JOURNAL, vol. 20, no. 1, pp. 41–50, Jun. 2026.
Section
Research Articles

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