How to solve the problem about "Conversion to logical from optim.problemdef.OptimizationConstraint is not possible!"
9 visualizaciones (últimos 30 días)
Mostrar comentarios más antiguos
Nicholas Deng
el 15 de Jul. de 2019
Comentada: NN
el 5 de Mayo de 2021
batteryNominalEnergy=optimvar('batteryNominalEnergy',1,'LowerBound',0,'UpperBound',20);
powerElectronicsRatedPower=optimvar('powerElectronicsRatedPower',1,'LowerBound',0,'UpperBound',10);
Ppv_load=optimvar('Ppv_load',simTime,1,'LowerBound',0,'UpperBound',9.9824e+03);
Ppv_batt=optimvar('Ppv_batt',simTime,1,'LowerBound',0);
Ppv_grid=optimvar('Ppv_grid',simTime,1,'LowerBound',0,'UpperBound',9.9824e+03);
Pcurtail=optimvar('Pcurtail',simTime,1,'LowerBound',0,'UpperBound',5000);
Pbatt_load=optimvar('Pbatt_load',simTime,1,'LowerBound',0);
Pbatt=Ppv_batt*Eta_inv-Pbatt_load/Eta_inv;
Esoh=optimexpr(simTime,1);
Esoh(1)=1;
if Pbatt(i-1)>=0 %% this line reports the arror
Esoh(i)=Esoh(i-1)-0.2*(sampletime/gvarYEARS2SECONDS/20+0.5*Pbatt(i-1)*sampletime/(batteryNominalEnergy*gvarKWH2WS*Esoh(i-1))/4500);
else
Esoh(i)=Esoh(i-1)-0.2*(sampletime/gvarYEARS2SECONDS/20-0.5*Pbatt(i-1)*sampletime/(batteryNominalEnergy*gvarKWH2WS*Esoh(i-1))/4500);
end
Hi, I have meet the problem in MATLAB using linprog. "Pbatt" can be positive or negative. when it is posive, the battery will be charging. And when it is negetive, the battery will be discharging. The equation above caculates the battery SOH whenever the battery is charging or discharging.
"Pbatt" is calculated from the optimization variables. But if I use "abs(Pbatt)", there will be an error that I can't use abs function.
Appreciate for your help!
18 comentarios
NN
el 5 de Mayo de 2021
Editada: NN
el 5 de Mayo de 2021
(sqrt(X^2)/X + 1)/2 * (cost2-cost1) + cost1 now takes us to cost1 if X < 0, and takes us to cost2 if X > 0 (and takes us to NaN if X is 0 exactly.)
The expression is giving Nan when X is 0, i am not sure if that gives the error for sqrt , can you please advice how can i avoid that Nan and it gives the answer 0 whenever it is Nan
Respuesta aceptada
Matt J
el 19 de Jul. de 2019
Editada: Matt J
el 19 de Jul. de 2019
Introduce variables r to represent bounds on Pbatt
r=optimvar('absPbatt',simTime1,'LowerBound',0);
prob.Constraints.r_upper=Pbatt<=r;
prob.Constraints.r_lower=Pbatt>=-r;
This is equivalent to abs(Pbatt)<=r. Now, add sum(r) to your objective
prob.Objective=prob.Objective+sum(r);
and finally
prob.Constraints.SOH = Esoh(2:end)==Esoh(1:end-1)-0.2*(sampletime/gvarYEARS2SECONDS/20+0.5*r(1:end-1)*sampletime/(batteryNominalEnergy*gvarKWH2WS*Esoh(1:end-1))/4500);
2 comentarios
Matt J
el 22 de Jul. de 2019
Hi Matt J, please have a look at my question too. I am facing a similar challenge as Nicholas
I am trying copy the idea you shared earlier in your answer, but the last piece of code (i.e. prob.Constraints.SOH) would be different in my case. I am struggling to understand what you did here so I am unable to adapt your answer to my application.
Más respuestas (0)
Ver también
Categorías
Más información sobre Problem-Based Optimization Setup en Help Center y File Exchange.
Productos
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!