www.pudn.com > PV.rar > MPPtrackIref.m.txt, change:2016-10-20,size:871b


% ECEN2060 DM 2/19/08 
% Simple MPP "perturb and observe" tracking algorithm  
% using Boost DC-DC input current Iref as the control variable 
% Pold, Iref and Increment are initialized in InitializeMPPtrackIref.m 
% 
% Input: power P to be maximized 
% Output: reference current 
function y = MPPtrackIref(P) 
 
global Pold; 
global Iref; 
global Increment; 
 
IrefH = 5; % upper limit for the reference current 
IrefL = 0; % lower limit for the reference current 
DeltaI = 0.02; % reference current increment 
 
if (P < Pold) 
    Increment = -Increment; % change direction if P decreased 
end 
 
% increment current reference 
Iref=Iref+Increment*DeltaI; 
 
% check for upper limit 
if (Iref > IrefH) 
    Iref = IrefH; 
end 
 
% check for lower limit 
if (Iref < IrefL) 
    Iref = IrefL; 
end 
 
% save power value 
Pold = P; 
% output current reference 
y = Iref;