Error using transfer functions
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Please help me sort out the issue. I am not understanding why the gain block dimension is shown as 2, where as i am expecting only 1. Please see the attached screenshot of simulink blocks.
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Birdman
le 7 Nov 2017
It is normal for simulation to run faster if you substract Transfer functions from the model but the main reason it is slow is that there are too many mathematical calculations to be done and too many states coming up from transfer functions and integrators. The variable-step solver tries to automatically adjust the step size for solving the states but since this model is an electrical system and since naturally electrical systems tends to behave quickly, the solver reduces the step size to almost 1e-4 and this results in simulation to slow. I have some suggestions:
-First, try to find the most suitable sampling time for your model. This means discretizing the continuous blocks in a suitable manner(Transfer Functions and Integrators). Because the variable step solver automatically increases the step size(narrows) in order to give you a solution but this results in slow simulation. I suggest you to look for Bode Plots of Transfer functions and controllers in your model.
-Second, be careful with the potential algebraic loops while discretizing the system.
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Shyam
le 30 Nov 2017
14 commentaires
Ramu Nair R
le 30 Nov 2017
Modifié(e) : Ramu Nair R
le 1 Déc 2017
I installed latest version and opened the model. I am trying to use memory blocks instead of delay block. Also, is it necessary to use z domain for transfer function. The block is a part of a bigger system, which are in continuous time, fixed step and solver is Runge-kutta
Ramu Nair R
le 1 Déc 2017
Modifié(e) : Ramu Nair R
le 1 Déc 2017
It worked. The problem was with initial condition. Thank you very much for your time and effort.
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