it's the matlab code that I wrote. I'm not sure about it, if anyone have better idea for it, plz help me.

dIpv_dVpv=-(Np*I0*q/Ns*A*k*T)*exp((q*Vpv)/Ns*A*k*T);

if dIpv_dVpv > -1.5*(Ipv(i,:)/Vpv)

Vpv=Vpv(i-1,:)+dV;

elseif dIpv_dVpv < -0.9*(Ipv(i,:)/Vpv)

Vpv=Vpv(i-1,:)-dV;

end

You can have look at this publication:

https://www.researchgate.net/publication/274068844_Simulation_of_Incremental_Conductance_MPPT_based_Two_phase_Interleaved_Boost_Converter_using_MATLABSimulink

Conference Paper Simulation of Incremental Conductance MPPT based Two phase I...

Refere to the following page

https://www.mathworks.com/discovery/mppt-algorithm.html