Modelling of solar cell: offset in short-circuit current

Discussion in 'General Electronics Chat' started by l0st_l0rd, Jul 18, 2016.

  1. l0st_l0rd

    Thread Starter New Member

    Apr 29, 2013
    Dear members

    I am trying to simulate the IV curve of a solar cell in reverse and forward bias. I have used bishop equation that you can see in the following picture.


    The mathermatical model is in good accordance with measurement. However, when I simulate it in SPICE, I have an offset in current which I think is related to the way I have added the leakage part.


    Here is my SPICE code. I will be thankful to have help for correction.

    .param a=1.987261e-01
    .param b=2.741757
    .param Vbr=-1.865206e+01

    .MODEL diode1 D(is={3.71896e-10}, n=1, xti=3)
    .MODEL diode2 D(is={1.178667e-05}, n=2, xti=3)

    Iphoto 0 internal 8.05
    D1 internal 0 diode1
    D2 internal 0 diode2
    Rsh internal n1 92.3597
    G1 0 n1 value={1+a*pow((1-(V(internal)/ Vbr),-1*b))}
    Rs output internal 0.00252

    .dc Vbias -18 1 0.01​