Operation Characteristics of Bypass Diode for PV Module

태양전지 모듈의 바이패스 다이오드 동작 특성 분석

  • 김승태 (건국대학교 전기공학과) ;
  • 박지홍 (건국대학교 전기공학과) ;
  • 강기환 (한국에너지기술연구원 태양광발전연구센터) ;
  • 화이티루 (건국대학교 전기공학과) ;
  • 안형근 (건국대학교 전기공학과) ;
  • 유권종 (한국에너지기술연구원 태양광발전연구센터) ;
  • 한득영 (건국대학교 전기공학과)
  • Published : 2008.01.01


In this paper, an I-V characteristics of bypass diode has been studied by counting the shading effect in photovoltaic module. The shadow induces hot spot phenomenon in PV module due to the increase of resistance in the current path. Two different types of PV module with and without bypass diode were fabricated to expect maximum output power with an increasing shading rate of 5 % on the solar cell. Temperature distribution is also detected by shading the whole solar cell for the outdoor test. From the result, the bypass diode works properly over 60 % of shading per cell with constant output power. Maximum power generation in case of solar cell being totally shaded with bypass diode decreases 41.3 % compared with the one under STC(Standard Test Condition). On the other hand, the maximum output power of the module without bypass diode gradually decreases by showing hot spot phenomenon with the increase of shading ratio on the cell and finally indicates 95.5 % of power loss compared with the output under STC. Finally the module temperature measured increases around $10^{\circ}C$ higher than that under STC due to hot-spots which come from the condition without bypass diode. It has been therefore one of the main reasons for degrading the PV module and shortening the durability of the PV system.


Hot spot;Bypass diode;Shading;PV modules


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