光伏组件面功率特性是影响太阳能飞机性能指标的关键因素之一。首先建立了考虑光伏组件表面温度、太阳能飞机飞行高度、纬度及一年四季等因素的光伏组件面功率模型,分析了光伏组件在一年范围内的日均直射、日均水平面功率随飞行高度、纬度和季节等关键设计指标参数的变化规律,对比研究了3种跟踪采能方式下的主动式光伏组件(TPM)的逐时、日均面功率特性。结果表明:在一天的光照时间内和全年范围内,主动式光伏组件能显著提高光伏组件的面功率特性。然后,参考了典型的太阳能飞机"Helios"和"Zephyr",综合考虑能源与气动特性,初步设计了一种采用主动式光伏组件的高空驻留太阳能飞机布局方案,通过分析其日均净面功率特性得出:合理设计主动式光伏组件,可以显著提高太阳能飞机的日均净面功率约32%~66%,甚至可达116%。这些结论均说明,从采能效率和气动特性两方面综合来说,所提出的基于主动式光伏组件的布局设计思想在高空驻留太阳能飞机总体布局设计时具有良好的应用优势。
The characteristics of power density of PV(photovoltaic) modules play a key part in the flight performance of solar-powered airplanes.Firstly,this paper establishes a model of power density for PV modules,taking into consideration the temperature of PV modules,flight altitude,flight latitude,and year-round seasons.Based on this model,this poper analyzes the variation of the day-average power density of PV modules for horizontal surfaces and surfaces perpendicular to the Sun.this paper presents a comparative study of the characteristics of power density of tracking PV modules(TPM) under three types of tracking methods,and the results show that tracking PV modules improve the power performance during both the daylight in one day and during a whole year.Then,based on two typical solar-powered airplanes,"Helios" and "Zephyr",this paper proposes a new concept of solar-powered airplane with tracking PV modules and analyzes their effects on improving the average net power density.The results show that the tracking PV modules can increase power density by 32% to 66%,and at times even up to 116% if well designed.From the point of view of both energy and aerodynamic efficiency,this paper shows that it is necessary to apply the tracking PV modules to designing stationary high-altitude solar-powered airplanes due to their superiorities.