How to write the algorithm to obtain the I-V and P-V characteristics of the solar panels?

Hello everyone,

I have the following equations:

function F = solar1(x)

q = 1.60217662e-19;

k = 1.38064852e-23;

T = 298.15; % Temperature in degrees 25. This one is in Kelvin.

Ns = 72;

Np = 1;

Voc = 44.6;

Vm = 35.4;

Isc = 5.43;

Im = 4.95;

n = 1.086;

Iph = x(1);

Io = x(2);

Vt = x(3);

Rs = x(4);

Rp = x(5);

F(1) = Np*Iph - Np*Io*(exp(Voc/Ns*Vt)-1) - ((Np*Voc)/(Ns*Rp));

F(2) = Np*Iph - Np*Io*(exp(Isc*Rs/Np*Vt)-1) - ((Isc*Rs)/Rp) - Isc;

F(3) = Np*Iph - Np*Io*exp((((Np*Vm)+(Ns*Im*Rs))/(Ns*Np*Vt)) -1) - Np*(((Np*Vm)+(Ns*Im*Rs))/(Ns*Np*Rp))- Im;

F(4) = (((Np/Ns*Vt)*Io*(exp((Vm + ((Im*Ns*Rs)/Np))/Ns*Vt)) + (1/(Ns*Rp)/Np))/(1 + (Rs*Vt)*Io*(exp((Vm + ((Im*Ns*Rs)/Np))/Ns*Vt)) + (Rs/Rp))) - (Im/Vm);

F(5) = (((-Np/Ns*Vt)*Io*exp((Isc*Ns*Rs)/(Np*Ns*Vt)) - (Np/Ns*Rp)) / (1+(Rs/Vt)*Io*exp((Isc*Ns*Rs)/(Np*Ns*Vt)) + (Rs/Rp))) + 1/Rp;

F(6) = (((-Np/Ns*Vt)*Io*(exp(Voc/Ns*Vt)) - (1/Ns*Rp/Np)) / (1 + (Rs/Vt)*Io*(exp(Voc/Ns*Vt)) + (Rs/Rp))) + 1/Rs; F(7) = Vt - n*k*T/q;

end

I am using 'levenberq-marquardt' to solve the system above which i am able to calculate the five unknown parameters (x(1),x(2)...x(5)).

Then what i need to do is to write an algorithm to be able to plot the graphs for I-V and P-V characteristics anyone can give me a hint on how to do that?

Thanks in advance.

[John D'Errico]

This can be almost an impossible question for people to answer, because only you know what this aggregation of completely undocumented code does, what the variables mean, etc.

[Charalampos Ioannou]

Hello John,

I have the following equations. </matlabcentral/answers/uploaded_files/98436/Capture.PNG>

I need 5 equations to solve the system to find out the 5 unknown parameters Iph,Io,Vt,Rs and Rp. I solve this one with 'levenberq-marquerdt'.

Now i want to apply this to calculate the I-V and P-V characteristics of the solar panel.