Bypass diode characteristic effect on the behavior of solar PV array at shadow condition

Bypass diodes are used in PV arrays to protect sunny modules against the negative effects of shaded ones. Bypass diodes characteristic mainly consist of two factors: turn on resistance and forward voltage. These factors could have affect on the output of solar photovoltaic array at shadow condition. This paper tries to analyze this effect by the use of two solar cells connected in series and protected by no-overlapped bypass diodes. MATLAB software has been used for simulation. In experimental process different diodes have been compared. Results show that bypass diodes acts like a shifter in I-V curve of solar array.