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General => General Technical Chat => Topic started by: ledtester on October 03, 2022, 09:31:37 pm

Title: W. Marshall Leach's Superposition technique for dependent sources
Post by: ledtester on October 03, 2022, 09:31:37 pm

I just ran across this series of videos which shows a technique developed by W. Marshall Leach to analyze circuits with dependent sources without having to perform source transformations:

https://www.youtube.com/playlist?list=PLOunECWxELQQZROtya37L3EkisfVlgqy7 (https://www.youtube.com/playlist?list=PLOunECWxELQQZROtya37L3EkisfVlgqy7)

The paper describing the technique in full is available on W. Marshall Leach's web page at Georgia Tech:

https://leachlegacy.ece.gatech.edu/ (https://leachlegacy.ece.gatech.edu/)

Paper link: https://leachlegacy.ece.gatech.edu/papers/superpos.pdf (https://leachlegacy.ece.gatech.edu/papers/superpos.pdf)

The background history the paper is just as intriguing as the technique... from the web site:

Quote

Superposition of Dependent Sources is Valid in Circuit Analysis. This paper was originally submitted to the IEEE Trans. on Education in early 1994. It was rejected because the reviewer was of the opinion that the methods it described were not valid. A request to have it reviewed again by a competent reviewer went unanswered. It was then submitted to the IEEE Trans. on Circuits and Systems in 1995. The reviewers recommended several changes. The paper was revised and submitted a second time in 1996. The reviewers then recommended that it be submitted instead to the IEEE Trans. on Education. It was submitted again to that journal. The editor rejected the paper without having it peer reviewed. The paper has been published on the internet since late 1996. I have received many emails from people who have found it useful. One came from an author of a circuits textbook who said that it taught him some new tricks.

Title: Re: W. Marshall Leach's Superposition technique for dependent sources
Post by: ledtester on October 12, 2022, 06:36:10 pm

An update...

W. Marshall Leach's paper was first presented to journals in 1994 but ultimately was never accepted. It remained available only on the Internet. However, in 2011 a response to it was published in the International Journal of Electronics by Robert I. Damper:

Can dependent sources be suppressed in electrical circuit theory?
https://eprints.soton.ac.uk/271202/1/superposition.pdf

It affirms the conclusions of Leach's reasoning providing perhaps a slightly more robust proof of the technique.