Simple DC/DC Converter

Hi,

I am getting really stuck trying to write a simple DC/DC converter model within Simulink for a fuel cell vehicle. The main problem I am having is that most models use switching circuits which slow my model down significantly. All I want is a block that does a steady state approximation, ideally with an efficiency, but for now I'd be happy with 100% efficiency so just V(out) = 2*V(in), I(out) = 1/2*I(in).

I've tried writing a model using Simulink blocks only, but I get an algebraic loop. The rest of my model is using SimPowerSys, so I've also tried using the Transformer block with Simscape-SimPowerSys interface, but I the following error;

"Steady state solve failed to converge. ...Nonlinear solver: Linear Algebra error. Failed to solve using iteration matrix. ......Equations of one or more components may be dependent or inconsistent. This can cause problems in transient initialization. Here is the set of components involved:"

I'm genuinely confused as to why a simple model is causing such issues, can anyone point me in the direction of something that will work?

Tom

Answer 1

[Mahmoud Saleh]

I would say take a look at the following models, you should find the detailed modelling steps: https://www.mathworks.com/matlabcentral/fileexchange/63330-current-controller-dc-dc-bidirectional-converter?s_tid=prof_contriblnk

https://www.mathworks.com/matlabcentral/fileexchange/63791-voltage-control-dc-dc-bidirectional-converter?s_tid=prof_contriblnk

https://www.mathworks.com/matlabcentral/fileexchange/63949-voltage-control-dc-dc-boost-converter?s_tid=prof_contriblnk

Answer 2

[Babak]

Try DC DC converter available in Simscape toolbox. It is easy to use and has no pulses.