유연 InGaP/GaAs 2중 접합 태양전지 모듈의 신뢰성 확보를 위한 실험 및 수치 해석 연구

Flexible solar cells have attracted enormous attention in recent years due to their wide applications such as portable batteries, wearable devices, robotics, drones, and airplanes. In particular, the demands of the flexible silicon and compound semiconductor solar cells with high efficiency and high reliability keep increasing. In this study, we fabricated a flexible InGaP/GaAs double-junction solar module. Then, the effects of the wind speed and ambient temperature on the operating temperature of the solar cell were analyzed with the numerical simulation. The temperature distributions of the solar modules were analyzed for three different wind speeds of 0 m/s, 2.5 m/s, and 5 m/s, and two different ambient temperature conditions of 25oC and 33oC. The flexibility of the flexible solar module was also evaluated with the bending tests and numerical bending simulation. When the wind speed was 0 m/s at 25 oC, the maximum temperature of the solar cell was reached to be 149.7oC. When the wind speed was increased to 2.5 m/s, the temperature of the solar cell was reduced to 66.2oC. In case of the wind speed of 5 m/s, the temperature of the solar cell dropped sharply to 48.3oC. Ambient temperature also influenced the operating temperature of the solar cell. When the ambient temperature increased to 33oC at 2.5 m/s, the temperature of the solar cell slightly increased to 74.2oC indicating that the most important parameter affecting the temperature of the solar cell was heat dissipation due to wind speed. Since the maximum temperatures of the solar cell are lower than the glass transition temperatures of the materials used, the chances of thermal deformation and degradation of the module will be very low. The flexible solar module can be bent to a bending radius of 7 mm showing relatively good bending capability. Neutral plane analysis was also indicated that the flexibility of the solar module can be further improved by locating the solar cell in the neutral plane.