I am getting following error while running a program. "

function [P_eng, P_elecmach] = fcn(v_veh, P_tractive, SOC)

%define variables

P_eng_min = 10; %kW

P_eng_max = 80; %kW

R_wheel = 0.2794; %m

G_diff = 0.25; %Unit less

G_trans_min = 0.3; %Unit less

W_eng_min = 16.6667; %revolutions per second

Scale = 1;

% The first thing to check is whether the W_eng (Engine Speed) is below

% its minimum level. The minimum engine speed which correspond to the

% minimum engine power level is 1000 rpm or 16.6667 rps.

% That will correspond to around 2.2 m per second or 131 m per minute.

v_veh_min = R_wheel * G_diff * G_trans_min * W_eng_min * 2 * pi;

% 2.1944 = 0.2794 * 0.25 * 0.3 * 16.6667 * 2 * pi

% if v_veh < v_veh_min

% P_eng = 0;

% P_elecmach = P_tractive;

%When P_tractive = 0, P_eng = 0

% P_elecmach = 0

%This means that vehicle is stationary

%When P_tractive < 0, P_eng = 0

% P_elecmach = P_tractive (negative value)

%This means that vehicle is stationary

if v_veh < v_veh_min

P_eng = 0;

P_elecmach = P_tractive; %P_elecmach >0 => battery is discharging

elseif P_tractive < 10

P_eng = 0;

P_elecmach = P_tractive; %P_elecmach >0 => battery is discharging

elseif P_tractive > 80

P_eng = P_eng_max;

P_elecmach = P_tractive - P_eng_max; %P_elecmach >0 => battery is discharging

else %P_tractive > 10 && P_tractive < 80

P_elecmach = (-1)*(P_eng_max - P_tractive)*(0.6-SOC)*Scale;

P_eng = P_tractive - P_elecmach;

end

return

%%Error message

Function 'Power Management Strategy' (#530.1490.1529), line 46, column 22:

"(-1)*(P_eng_max - P_tractive)*(0.6-SOC)"

Size mismatch (size [1 x 1] ~= size [3 x 1]).

The size to the left is the size of the left-hand side of the assignment.

Function 'Power Management Strategy' (#530.1547.1552), line 47, column 9:

"P_eng"

Answer 1

[Esen Ozbay]

You need to tell us what SOC is, but you probably input an array into the function while you were running it. SOC should be a scalar number.