Author Topic: Inverse of power  (Read 3992 times)

0 Members and 1 Guest are viewing this topic.

Offline Vtile

  • Frequent Contributor
  • **
  • Posts: 990
  • Country: fi
  • Ingineer
Re: Inverse of power
« Reply #25 on: August 10, 2017, 03:05:25 pm »
voltage and current act in differently in conductance domain
Yes they act differently in analysis perspective, see below

You keep talking about "conductance domain", as if there is such a thing (there isn't). Also you previously said there is no such thing as KCL or KVL in "conductance domain", but of course there is. Those laws are universal, they don't depend on what nomenclature you use.
No I didn't claim that the KCL or KVL doesn't exist on "conductance domain", but I did say something like they do not exist in a way we are accustomed. The reason I removed it were that the claim is so bold and KVL and KCL are so central laws. I had no attention to pull these out at all (partly because I would make sure my logic is solid and shouldn't have any logic flaws or it this topic will be troll fest to ad nauseam), put the topic lives its own live. If we compare the KCL and KVL in these two "domains" or "planes", what ever you want to call the circuit models, the laws stay the same, but the object of the law (potential or current) will be swapped. KCL handless voltage and KVL current. This is pretty obvious when you look the parallel resistors and how we use conductance to calculate the equivalent of them.

The conductance domain is only model or an visualisation of the domain that conductance and the "law of conductance (I=G*U)" will form, if applied rigorously and R-domain circuit is converted to G-domain. I'm visual thinker so I like the less-abstract visual modeling.

Also, I notice you keep editing your earlier posts in the thread and changing your words. This makes it impossible to follow the thread since it is like shifting sands. If you want people to engage with you, please don't do that.
Yes, I tried to clarify some posts late yesterday evening as the subject is a bit odd , some would even say controversial. The KCL/KVL edit. were only one where I removed something.
 

Offline alm

  • Super Contributor
  • ***
  • Posts: 1257
  • Country: 00
Re: Inverse of power
« Reply #26 on: August 10, 2017, 04:11:17 pm »
How would the analysis of a parallel resistor circuit be any different in your 'conductance domain'? You would still figure out the voltage across the resistors from KVL (assuming it is fed from a voltage source), and subsequently determine the current through each resistor using a (modified) Ohm's law (V/R or VG). Then through KCL you can sum up the currents and use that to figure out substitution resistance/conductance. The only difference is that you use multiplications instead of divisions, which makes the math a bit easier.
 

Offline Vtile

  • Frequent Contributor
  • **
  • Posts: 990
  • Country: fi
  • Ingineer
Re: Inverse of power
« Reply #27 on: August 10, 2017, 04:46:53 pm »
Like I wrote before I have only a few days though of this so I'm not formed a picture of it as a whole and I haven't gone to admittance at all, while exposure to admittance calculus is one key reasons I have had interest of this, but not only a few days ago Trondes series of posts or article (of simplified mains network analysis) and trying to figure out the current transformer fed circuit trickered my interest again. That said.

The trick is that in our parallel series resistor case they all share the same potential difference as KVL shows us. When you convert them to conductance and draw the circuit again based on addition of series resistors you end up conclusion that what is shown as parallel with resistors (r-domain) is in series with conductance representation and other way around. I haven't put too much true analysis of sources, but if we apply the series and parallel  principle they also swap. Same logic also works with power.

Nothing new, maybe just viewpoint.
 

Online IanB

  • Super Contributor
  • ***
  • Posts: 9593
  • Country: us
Re: Inverse of power
« Reply #28 on: August 10, 2017, 05:52:56 pm »
Like I wrote before I have only a few days thought of this

If you only have a few days of learning about these subjects it is really much too soon to be formulating these arguments. Even as a student you should expect to spend months or years developing an understanding.

Quote
The trick is that in our parallel series resistor case they all share the same potential difference as KVL shows us. When you convert them to conductance and draw the circuit again based on addition of series resistors you end up conclusion that what is shown as parallel with resistors (r-domain) is in series with conductance representation

No, this isn't true. The resistors are in parallel because this is the physical topology. They remain in parallel even if you use conductances instead of resistances to describe the voltage/current relationship. The arithmetic changes to addition of conductances, but that does not change the topology.
I'm not an EE--what am I doing here?
 

Offline ebastler

  • Super Contributor
  • ***
  • Posts: 3047
  • Country: de
Re: Inverse of power
« Reply #29 on: August 10, 2017, 06:25:18 pm »
To get back to the original question, the inverse of power would be "sloth", I think.
Time required per work done, measured in s/J.
 
;)
 
The following users thanked this post: george.b

Offline Zero999

  • Super Contributor
  • ***
  • Posts: 13190
  • Country: gb
  • 0999
Re: Inverse of power
« Reply #30 on: August 10, 2017, 06:26:30 pm »
To get back to the original question, the inverse of power would be "sloth", I think.
Time required per work done, measured in s/J.
 
;)
Nah, the inverse of power is rewop.
 

Offline Vtile

  • Frequent Contributor
  • **
  • Posts: 990
  • Country: fi
  • Ingineer
Re: Inverse of power
« Reply #31 on: August 11, 2017, 01:21:01 pm »
Quote
The trick is that in our parallel series resistor case they all share the same potential difference as KVL shows us. When you convert them to conductance and draw the circuit again based on addition of series resistors you end up conclusion that what is shown as parallel with resistors (r-domain) is in series with conductance representation

No, this isn't true. The resistors are in parallel because this is the physical topology. They remain in parallel even if you use conductances instead of resistances to describe the voltage/current relationship. The arithmetic changes to addition of conductances, but that does not change the topology.
So what happens in the Thevenin-Norton Equivalent circuits aka source transformation where only one of the sources represents directly a real world and the topology do chance when applied. Note that you should explain this analytical transformation trick now with physical topology.

« Last Edit: August 11, 2017, 01:22:46 pm by Vtile »
 

Offline Brumby

  • Supporter
  • ****
  • Posts: 9407
  • Country: au
Re: Inverse of power
« Reply #32 on: August 11, 2017, 04:45:34 pm »
Why is it that I am caught on the fact that with that transformation, you are changing the type of power source AND the placement of the resistor...?
 

Offline Vtile

  • Frequent Contributor
  • **
  • Posts: 990
  • Country: fi
  • Ingineer
Re: Inverse of power
« Reply #33 on: August 11, 2017, 05:25:24 pm »
To keep it conpatible to regular model obviously and because of the ideal source properties there needs to be those components there to fullfill the route and division of power.

..OK, need to get another Aspirin, can't think straight.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf