# Positive Negative sequence seperation with DDSRF **URL:** \ **Category:** General\ **Tags:** plecs, c-script\ **Created:** [August 9, 2026, 7:00pm UTC](https://forum.plexim.com/t/positive-negative-sequence-seperation-with-ddsrf/3261 "2026-08-09T19:00:04Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![smmuabd1](https://avatars.discourse-cdn.com/v4/letter/s/e495f1/32.png) [@smmuabd1](https://forum.plexim.com/u/smmuabd1)\ **Post date:** [August 9, 2026, 7:00pm UTC](https://forum.plexim.com/t/positive-negative-sequence-seperation-with-ddsrf/3261/1 "2026-08-09T19:00:04Z")
I am building a cascaded H bridge model for unbalanced conditions and need a positive, negative sequence seperation approach, but any approach I have tried does not work so far are any pre built models or exampes of positive and negative sequence seperation for convertor control strategy. ---
**Author:** ![Bryan\_Lieblick](https://dub1.discourse-cdn.com/flex006/user_avatar/forum.plexim.com/bryan_lieblick/32/10_2.png) [@Bryan\_Lieblick](https://forum.plexim.com/u/Bryan_Lieblick)\ **Post date:** [August 10, 2026, 5:24pm UTC](https://forum.plexim.com/t/positive-negative-sequence-seperation-with-ddsrf/3261/3 "2026-08-10T17:24:28Z")
Please review the solutions in this previous forum post to see if they meet your needs. > [@Symmetrical Components Extraction in Natural abc Frame](https://forum.plexim.com/t/symmetrical-components-extraction-in-natural-abc-frame/1252/2): > > Hello Nur, Signals in PLECS can only be real values. Symmetrical component decomposition is a phasor / complex number operation. You can use the “Fourier Transform” block from the library to convert a sequence of real-values into the magnitude and phase of the specified harmonic. Attached are two models that show different approaches to symmetrical component extraction. The “sequence\_cscript” example is more conventional in that it takes the Fourier Transform of the real-valued inputs and th…