A reconfiguration method for photovoltaic array of stratospheric airship based on multilevel optimization algorithm

Abstract

Reducing the mismatch loss to increase the output power of the photovoltaic (PV) array is crucial for extending the flight time of stratospheric airships. This paper presents a reconfiguration system for PV arrays based on a switch matrix designed for stratospheric airships. The proposed system employs a multilevel optimization reconfiguration algorithm that combines smart choice, greedy, and Munkres' assignment algorithms. Simulations were conducted under single working conditions, full-day sunlight cycles, and full-year PV array reconfigurations, respectively. The results demonstrated that the reconfigured PV array significantly improved the output power with a smooth PV curve. The instantaneous power under extreme working conditions could be increased by 50.1%. Furthermore, during the 7-day simulation process, the average daily power output of the PV array increased by 14.68%, whereas the output fluctuation during circular cruising was reduced. The reconfiguration system offers greater advantages during months with weak irradiance in high-latitude regions, where the daily output power of the PV array can be increased by up to 24.46%. This significantly reduces the installation area and weight ratio of a stratospheric airship PV array.