Simulation and Structured Text Generation for MPC Controller Block

This example shows how to simulate and generate structured text for an MPC Controller block by using Simulink® PLC Coder™ software. The generated code uses single-precision data.

Required Products

To run this example, Model Predictive Control Toolbox™, Simulink®, and Simulink PLC Coder™ are required.

if ~mpcchecktoolboxinstalled('simulink')
    disp('Simulink is required to run this example.')
    return
end
if ~mpcchecktoolboxinstalled('plccoder')
    disp('Simulink PLC Coder is required to run this example.');
    return
end
if ~mpcchecktoolboxinstalled('mpc')
    disp('MPC Toolbox is required to run this example.');
    return
end

Define Plant Model and MPC Controller

Define a SISO plant.

plant = ss(tf([3 1],[1 0.6 1]));

Define the MPC controller for the plant.

Ts = 0.1;   %Sample time
p = 10;     %Prediction horizon
m = 2;      %Control horizon
Weights = struct('MV',0,'MVRate',0.01,'OV',1); % Weights
MV = struct('Min',-Inf,'Max',Inf,'RateMin',-100,'RateMax',100); % Input constraints
OV = struct('Min',-2,'Max',2); % Output constraints
mpcobj = mpc(plant,Ts,p,m,Weights,MV,OV);

Simulate and Generate Structured Text

Open the Simulink model.

mdl = 'mpc_plcdemo';
open_system(mdl)

To generate structured text for the MPC Controller block, put the MPC block inside a subsystem block and treat the subsystem block as an atomic unit. Select the Treat as atomic unit property of the subsystem block.

Simulate the model in Simulink.

close_system([mdl '/Control System/MPC Controller'])
open_system([mdl '/Outputs//References'])
open_system([mdl '/Inputs'])
sim(mdl)

-->Converting model to discrete time.
-->Assuming output disturbance added to measured output #1 is integrated white noise.
-->"Model.Noise" is empty. Assuming white noise on each measured output.

To generate code by using the Simulink PLC Coder, use the plcgeneratecode command.

plcgeneratecode([mdl '/Control System']);

Close the Simulink model and return to the original directory.

bdclose(mdl)