i have written the following code for pso based mppt but the simulink model gets stuck at one value and the duty does not change.... kindly suggest me the error

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puneet joshi on 5 Apr 2016

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https://au.mathworks.com/matlabcentral/answers/277323-i-have-written-the-following-code-for-pso-based-mppt-but-the-simulink-model-gets-stuck-at-one-value

Answered: Nisar Ahmed on 30 Apr 2020

function D = PSO(Param, V, I)
% MPPT controller based on the Perturb & Observe algorithm.
% D output = Duty cycle of the boost converter (value between 0 and 1)
%
% V input = PV array terminal voltage (V)
% I input = PV array current (A)
%
% Param input:
%Dinit = Param(1);  %Initial value for D output
Dmax = Param(2);   %Maximum value for D
Dmin = Param(3);   %Minimum value for D
deltaD = Param(4); %Increment value used to increase/decrease the duty cycle D
persistent D_mat_cur Power_old vel max_power_new max_power_old Power_new global_best_duty self_best_duty D_mat_new
pop_size=10;
vmin=-1*deltaD;
vmax=deltaD;
%%wmax=0.9;
%%wmin=0.4;
c1=2;
C=1;
c2=2;
if isempty(Power_old)
      %%intiallize all matrices
      Power_old=zeros(1,pop_size);
      Power_new=zeros(1,pop_size);
      vel=zeros(1,pop_size);
      D_mat_new=zeros(1,pop_size);
      D_mat_cur=rand(1,pop_size);
      vel=rand(1,pop_size).*(vmax-vmin)+vmin;
      for i=1 : pop_size
          if (D_mat_cur(i)>Dmax)
              D_mat_cur(i)=Dmax;
          end
      end
      for i=1 : pop_size
          if (D_mat_cur(i)<Dmin)
              D_mat_cur(i)=Dmin;
          end
      end
      for iter =1:pop_size
          D=D_mat_cur(iter);
          pause(0.0001)
          Power_old(iter)=V*I;
      end
      [max_power_old,global_index]=max(Power_old);
      self_best_duty=D_mat_cur;
      global_best_duty=D_mat_cur(1,global_index);
  end
iter=0;
max_iter=100;
while iter<max_iter
      iter=iter+1;
      %calculate power
      for iter =1:pop_size
          D=D_mat_cur(iter);
          pause(0.0001)
          Power_new(iter)=V*I;
      end
      %%update self best duty
      for i=1:pop_size
          if (Power_new(1,i)>Power_old(1,i))
              Power_old(1,i)=Power_new(1,i);
              self_best_duty(1,i)=D_mat_cur(1,i);
          end
      end
      %%update global best duty
      [max_power_new,index]=max(Power_old);
      if (max_power_new>max_power_old)
          max_power_old=max_power_new;
          global_best_duty=D_mat_cur(1,index);
      end
   w=.001;   
      %%calculation of new velocity matrix
      for i=1 :pop_size
          vel(1,i)= C*(w.*vel(1,i) +c1*rand*(self_best_duty(1,i) - D_mat_cur(1,i))  +c2*rand*(global_best_duty-D_mat_cur(1,i)));
      end
      %%update positions
      D_mat_new=D_mat_cur+ vel;
      %%bring back the param that go out of the bounds
      %%upper limit
      for i=1 : pop_size
          if (D_mat_new(1,i)>Dmax)
              D_mat_new(1,i)=Dmax;
          end
      end
      %%lower limit
      for i=1 : pop_size
          if (D_mat_new(1,i)<Dmin)
              D_mat_new(1,i)=Dmin;
          end
      end
D_mat_cur=D_mat_new; 
end
[~,global_ind]=max(Power_new);
 D=D_mat_cur(1,global_ind);

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kamran etivand on 23 Nov 2017

Edited: Walter Roberson on 23 Nov 2017

Open in MATLAB Online

function Dnew = PSO(Vpv,Ipv)
%%Problem Definition
persistent particle_Position particle_Cost particle_Velocity GlobalBest_Position ...
    particle_Best_Position particle_Best_Cost GlobalBest_Cost
% persistent
nVar=1;             % Number of Decision Variables
VarSize=[1 nVar];   % Size of Decision Variables Matrix
VarMin=0.02;         % Lower Bound of Variables
VarMax=0.95;         % Upper Bound of Variables
%%PSO Parameters
MaxIt=2;      % Maximum Number of Iterations
nPop=3;        % Population Size (Swarm Size)
phi1=2.05;
phi2=2.05;
phi=phi1+phi2;
chi=2/(phi-2+sqrt(phi^2-4*phi));
w=chi;          % Inertia Weight
wdamp=1;        % Inertia Weight Damping Ratio
c1=chi*phi1;    % Personal Learning Coefficient
c2=chi*phi2;    % Global Learning Coefficient
% Velocity Limits
VelMax=0.1*(VarMax-VarMin);
VelMin=-VelMax;
%%Initialization
if isempty(particle_Position)
   particle_Position=zeros(nPop,1);
end
if isempty(particle_Cost)
   particle_Cost=zeros(nPop,1);
end
if isempty(particle_Velocity)
  particle_Velocity=zeros(nPop,1);
end
if isempty(particle_Best_Position)
  particle_Best_Position=zeros(nPop,1);
end
if isempty(particle_Best_Cost)
  particle_Best_Cost=zeros(nPop,1);
end
if isempty(GlobalBest_Cost)
  GlobalBest_Cost=0;
end
if isempty(GlobalBest_Position)
  GlobalBest_Position=unifrnd(VarMin,VarMax,VarSize);
end
BestCost=zeros(MaxIt,1);
nfe=zeros(MaxIt,1);
% PSO Main Loop
for it=1:MaxIt
      for i=1:nPop
          Dnew= particle_Position(i);
      particle_Cost(i)=Vpv*Ipv;
      if particle_Cost(i)>particle_Best_Cost(i)
              particle_Best_Position(i)=particle_Position(i);
              particle_Best_Cost(i)=particle_Cost(i);
            end  
              % Update Global Best
              if particle_Best_Cost(i)>GlobalBest_Cost
                  GlobalBest_Position=particle_Best_Position(i)
                  GlobalBest_Cost=particle_Best_Cost(i);
              end
      for i=1:nPop
          % Update Velocity
          particle_Velocity(i) = w*particle_Velocity(i) ...
              +c1*rand(VarSize)*(particle_Best_Position(i)-particle_Position(i)) ...
              +c2*rand(VarSize)*( GlobalBest_Position-particle_Position(i));
          % Apply Velocity Limits
          particle_Velocity(i) = max(particle_Velocity(i),VelMin);
          particle_Velocity(i) = min(particle_Velocity(i),VelMax);
          % Update Position
          particle_Position(i) = particle_Position(i) + particle_Velocity(i);
          % Apply Position Limits
          particle_Position(i) = max(particle_Position(i),VarMin);
          particle_Position(i) = min(particle_Position(i),VarMax);
          % Evaluation
      end
      end
       w=w*wdamp;
  end
     Dnew=GlobalBest_Position
  end