Improvement of endurance performance for high-altitude solar-powered airships: A review

The high-altitude airships have great potential in military and civilian applications with the advantages of long endurance and low operating costs. Solar energy, which can be converted into electrical energy through photoelectric cells, plays an important role in the endurance performance of high-altitude airships. However, due to the insufficient efficiency of photoelectric cells, the energy supply is still a significant limitation for high-altitude airships. Although many researchers have proposed a number of techniques to improve the endurance of airships, different methods are suitable to diverse operation conditions, which will result in inefficiency and complexity in selection of optimized techniques. Therefore, it is necessary to present a detailed review on improvement methods of high-altitude airship endurance. According to the features and functional principles of energy system of high-altitude airships, the improvement methods are classified into two categories: increasing the output electrical energy and reducing the energy consumption caused by wind resistance. The current problems and future trends of these methods are also discussed. The results can provide a reasonable reference in the selection of endurance improvement methods for the designers and researchers.