What can be wrong with the following code snippet written for search-skip-judge MPPT algorithm. It is based on equipower line in I-V plot that helps skip voltage ranges

function [V_mpp, P_mpp, duty_cycle] = SSJ_GMPPT(V_pv, I_pv, V_oc_mod, n, V_out)

% SSJ-GMPPT Maximum Power Point Tracking

% Inputs:

% V_pv: PV voltage measurement

% I_pv: PV current measurement

% V_oc_mod: Open-circuit voltage of a single PV module

% V_oc_string: Open-circuit voltage of the PV string

% n: Number of PV modules in the string

% V_out: Output voltage of the boost converter

%

% Outputs:

% V_mpp: MPP voltage

% P_mpp: MPP power

% duty_cycle: Duty cycle for the boost converter

% Persistent Variables

persistent V_ref P_m V_m I_sc_prev j V_end dP_dV_prev V_prev P_prev I_prev I_sc;

% Initialization

if isempty(V_ref)

% Initialize parameters

V_ref = 0.6 * V_oc_mod; % Initial operating voltage

V_end = 0.9 * n * V_oc_mod; % Ending voltage

P_m = 0; % Initialize maximum power

V_m = 0; % Initialize voltage at maximum power

I_sc_prev = 0; % Initialize previous short circuit current

j = 1; % Initialize module counter

dP_dV_prev =0;

V_prev =0;

P_prev =0;

I_prev =0;

I_sc = 0;

end

dV = 0.2; % Voltage increment

V_mpp = 0; % Initialize V_mpp to a default value

P_mpp = 0; % Initialize P_mpp to a default value

duty_cycle = 0; % Initialize duty_cycle to a default value

% 1. Searching Process (Incremental Conductance Method)

P_pv = V_pv .* I_pv; % Calculate PV power

% Calculate derivatives

if ~isempty(V_prev)

dP_dV = (P_pv - P_prev) / (V_pv - V_prev);

dI_dV = (I_pv - I_prev) / (V_pv - V_prev);

% IncCond conditions

if (dP_dV / P_pv) == (- dI_dV/I_pv)

P_m = P_pv;

V_m = V_pv;

V_ref = V_ref + dV; % Perturb voltage forward

elseif dP_dV > 0

V_ref = V_ref + dV; % Perturb voltage forward

else

V_ref = V_ref - dV;

end

else

dP_dV = 0;

dI_dV = 0;

V_ref = V_ref + dV;

end

V_prev = V_pv;

P_prev = P_pv;

I_prev = I_pv;

% 2. Check for SDP (Sign change of dp/dv)

SDP_found = false;

if ~isempty(dP_dV_prev) && (dP_dV_prev < 0 && dP_dV > 0)

SDP_found = true;

I_sc = I_pv; % Current of SDP

end

dP_dV_prev = dP_dV;

% 3. Skipping Process

if SDP_found

V_ref_new = P_m / I_sc; % New operating voltage

if V_ref_new > V_end

% GMPP found, end algorithm

V_mpp = V_m;

P_mpp = P_m;

% Duty cycle generation

duty_cycle = V_mpp / V_out;

return;

end

V_ref = V_ref_new;

j = j + 1; % Increment module counter

I_sc_prev = I_sc; % Update previous short circuit current

end

% 4. Judging Process

if SDP_found

if I_pv > 0.85 * I_sc && dP_dV > 0 % Checking condition

% Return to searching process

else

% Return to skipping process

V_ref = P_m / I_sc;

if V_ref > V_end

V_mpp = V_m;

P_mpp = P_m;

% Duty cycle generation

duty_cycle = V_mpp / V_out;

return;

end

j = j + 1;

I_sc_prev = I_sc;

end

end

% Duty cycle generation

duty_cycle = V_ref / V_out;

end