Please take a minute to review and accept our Terms of Use.
Welcome to the PLECS User Forum, where you can ask questions and receive answers from other members of the community.

Many technical questions regarding PLECS are answered on the Technical Solutions page of our website. Tutorial videos, specific application examples, and pre-recorded webinars are available on our YouTube page. Please follow us on LinkedIn for the latest Plexim news.

Why is simulation significantly faster when using lookup table with filtered output?

0 votes
125 views
I have a battery model which is described using a lookup table as in the attached models. If there is a low pass filter added to the output of the 2D lookup table simulation speed is significantly improved, and without it, it's much slower. How do you explain this? If you add another time constant to a model simulation should be more complicated and slower, so how does the filtering output of the lookup table influence simulation speed? In the given models there is a simplified lookup table that describes the battery cell voltage as a linear function of the state of charge and current V(SoC, I), but when I put real data of a battery the result in speed simulation is the same regarding the filter.
asked Dec 8, 2022 by matija (21 points)
edited Dec 8, 2022 by matija

1 Answer

+1 vote
 
Best answer
As per the simulation warning message in the model without the low pass filter (see the attached image), you have an algebraic loop in the system and this forces the PLECS solver to take a more iterative, computationally-intensive approach.

And the low pass filter simply injects the necessary delay to break the algebraic loop, and hence the model with it runs expectedly faster.
answered Dec 15, 2022 by Kris Eberle (1,384 points)
selected Dec 15, 2022 by matija
...