How to successfully impose constraints to a Control Variable with high priority #78
Description
Hi,
I am testing how to impose constraints to an extra Control Variable (CV).
I added an extra CV with no intention to control to a target but to respect constraints and for this to have more importance that the control to a target for the other existing CVs. But, I couldn't make it to work.
My code is as follow. Please, let me know how to setup the controller. Thanks!
using ModelPredictiveControl, ControlSystemsBase
using Plots
Ny=3;Nu=2;Nd=1
G = [ tf(1.90, [180, 1]) tf(1.90, [180,1]) tf(1.90, [180,1]);
tf(-0.74,[80, 1]) tf(0.74, [80, 1]) tf(0.74, [80, 1]);
tf(-0.5,[100, 1]) tf(2.0, [250, 1]) tf(0.1, [80, 1])]
Ts = 10.0
model = setop!(LinModel(G, Ts,i_u=[1,2],i_d=[3]), uop=[20, 20], yop=[50, 30, 25], dop=[20])
setname!(model; u=["mv1","mv2"], y=["cv1","cv2","ccv1"],d=["dv1"])
mpc = LinMPC(model, Hp=200, Hc=50, Mwt=[1.0, 1.0, 0.01], Nwt=[2.0, 2.0])
umin=[10,10];umax=[55,55];Δumax=[0.5,0.5]
ymin=[20,20,20];ymax=[70,70,35]
mpc = setconstraint!(mpc, umin=umin,umax=umax,Δumax=Δumax,c_ymin=fill(0.0,Ny),c_ymax=fill(0.0,Ny))
u=model.uop; d=model.dop; y = model(d) # x->y
x=initstate!(mpc,u,y,d) # u,y,d->x
ry, d = [50.0,30.0,25.0], [20]
y = model(d)
u = mpc(ry,d)
function test_mpc(mpc, model)
N = 200
ry, d = [50.0,30.0,25.0], [20]
u_data, y_data, ry_data = zeros(model.nu, N), zeros(model.ny, N), zeros(model.ny, N)
for i = 1:N
i == 51 && (ry = [50, 40, 25])
i == 101 && (ry = [54, 30, 25])
i == 151 && (d = [25])
y = model(d)
u = mpc(ry,d)
u_data[:,i], y_data[:,i], ry_data[:,i] = u, y, ry
updatestate!(mpc, u, y, d) # update mpc state estimate
updatestate!(model, u , d) # update simulator with the load disturbance
end
return u_data, y_data, ry_data
end
function plot_data(t_data, u_data, y_data, ry_data)
p1 = plot(t_data, y_data[1,:], label="meas.", ylabel="level")
plot!(p1, t_data, ry_data[1,:], label="setpoint", linestyle=:dash, linetype=:steppost)
plot!(p1, t_data, fill(45,size(t_data)), label="min", linestyle=:dot, linewidth=1.5)
hline!(p1,[ymin[1],ymax[1]],linestyle=:dot,label="")
p2 = plot(t_data, y_data[2,:], label="meas.", legend=:topleft, ylabel="temp.")
plot!(p2, t_data, ry_data[2,:],label="setpoint", linestyle=:dash, linetype=:steppost)
hline!(p2,[ymin[2],ymax[2]],linestyle=:dot,label="")
p3 = plot(t_data, y_data[3,:], label="meas.", legend=:topleft, ylabel="temp.2")
plot!(p3, t_data, ry_data[3,:],label="setpoint", linestyle=:dash, linetype=:steppost)
hline!(p3,[ymin[3],ymax[3]],linestyle=:dot,label="")
p4 = plot(t_data,u_data[1,:],label="cold", linetype=:steppost, ylabel="flow rate")
plot!(p4, t_data,u_data[2,:],label="hot", linetype=:steppost, xlabel="time (s)")
hline!(p4,[umin[1],umax[1]],linestyle=:dot,label="")
return plot(p1, p2, p3, p4, layout=(4,1),size=(900,500))
end
u_data, y_data, ry_data = test_mpc(mpc, model)
t_data = Ts*(0:(size(y_data,2)-1))
plot_data(t_data, u_data, y_data, ry_data)