독립형 태양광 발전시스템의 추적방식 모델링에 의한 효율개선

Abstract

ABSTRACT

Efficiency Improvement by Tracking Modeling for Stand Alone Photovoltaic System

We performed the research to improve the efficiency of stand-alone photovoltaic power system by integrating the generation efficiency of tracking PV array with the cost-efficiency of fixed PV array. A new PV array system was suggested, which could increase the generation efficiency comparing to the fixed PV array with a tilt without adding array. The influence of temperature was also considered for the efficiency in the variable fixed gear PV array. Theoretically, PV modules should be exposed to the sun as much as possible and be placed at the right angle to absorb the sun's rays. Actually, however, it was competitive that the monthly average generation time was from 3.5 hours to 3.8 hours and the utilization rate was from 13% to 16% when they were calculated at 30° of the tilt angle on 63 islands area in Korea . Heuksan island, located in longitude(Tokyo) 127° 27', latitude(Lat) 34° 41, was selected as the best place for modeling of stand-alone photovoltaic system in this paper. It brings the following results by using PVSYST Ver. 5.559 simulation program for stand-alone photovoltaic system and grid connected PV system.

First, it showed high generation efficiency of PV modules at 15° of array right after sunrise. As the solar altitude got higher, the generation efficiency was high at 28°. When the meridian altitude got closer, the generation efficiency was higher at 35°.

Second, annual PV generation capacity showed the highest at 28° of the array. Also, the utilization rate of solar energy was 14.67% and generation time was 3.52 hours.

It was ideal for Heuksan Island’s monthly PV generation on March and September when the array angle was 28°. It was at 15° from April to August and 35° from October to February. Solar energy utilization rate was 15.00 % and annual PV generation time was 3.6 hours in case of applying variable fixed gear PV array to stand-alone photovoltaic system in Heuksan island. Therefore, annual PV generation capacity and time were improved 2.25% and 2.27% than at 28° of the angle of fixed PV array.