Abstract
Partial shading often appears on photovoltaic (PV) strings installed in small space probes, such as moon exploration rovers, due to their body structures, reducing the power yield of PV strings. Such partial shading issues can be precluded by differential power processing (DPP) converters. However, in addition to a main dc-dc converter, a DPP converter is required, increasing the system complexity and cost. In this paper, several kinds of integrated pulse width modulation (PWM) converters that can reduce the system complexity thanks to the integration are reviewed and are quantitatively compared in terms of the switch and magnetic component counts, and voltage conversion ratio. Based on the comparison and consideration from the perspectives of reliability, circuit volume, and voltage conversion requirement, a single-switch single-magnetic integrated PWM converter with a resonant voltage multiplier (RVM) was selected as the best suitable topology for small exploration rovers. Furthermore, the improved version with a non-resonant voltage multiplier (NRVM) was also proposed to achieve further circuit miniaturization and improved reliability. The experimental verification tests using the proposed integrated PWM converter were performed emulating a partial-shading condition. The maximum power yield from the PV modules was improved by 11.1% thanks to the DPP function of the proposed integrated converter.
Highlights
When a partial shading occurs on a photovoltaic (PV) string composed of multiple submodules, module characteristics vary depending on the irradiance
PV strings in small exploration rovers suffer from partial shading issues because of a panning
PV strings in small exploration rovers suffer from partial shading issues because of a panning camera mounted on the top of the exploration rovers
Summary
When a partial shading occurs on a photovoltaic (PV) string composed of multiple submodules (hereafter call modules for simplicity), module characteristics vary depending on the irradiance. The power generation of the entire string significantly decreases because the shaded module no longer contributes to power generation due to the conduction of the bypass diode. MPP(s), occur in P-V characteristics of partially-shaded strings (see Figure 1c), suggesting that ordinary. Partial shading is a serious issue in space exploration rovers. The decreased energy yield due to partial shading translates to the increased volume and mass of the Energies 2019, 12, 1919; doi:10.3390/en12101919 www.mdpi.com/journal/energies
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
