Talk:Per-unit system

I added and explained algebraic proofs on why Voltage and Current per unit are the same on both sides of an ideal transformer. I added these proofs to the beginning of the transformer section of this per-unit system page. - elinxie — Preceding unsigned comment added by elinxie (talk • contribs) 06:53, 8 December 2016 (UTC)

I added some text and an example to the transformer section as I believe that it is important to talk about some of the conventions and show how they work within this section, even though it was already mentioned above. I also added a formula to change one per unit impedance to another per unit impedance at another set base values. - mguttenberg — Preceding unsigned comment added by Mguttenberg (talk • contribs) 06:53, 8 December 2016 (UTC)

This is wrong, but I'm too busy to fix it now.


 * $$I_{base} = \frac{P_{base}}{V_{base}} = 1 pu$$
 * $$Z_{base} = \frac{V_{base}}{I_{base}} = 1 pu$$
 * $$Y_{base} = \frac{1}{Z_{base}} = 1 pu$$

The example at the bottom is correct though so overall the article is fine. — Preceding unsigned comment added by 164.107.165.53 (talk • contribs)

14-Apr-2013: I followed the link for short circuit, but it took me to short circuit in a computer programming context, not a power systems context. I don't know how to fix this, but it would be great if someone could... — Preceding unsigned comment added by 216.52.185.71 (talk) 12:00, 14 April 2013 (UTC)
 * ✅ (Although, I couldn't find any article specifically about short-circuit evaluation in power systems, so I just linked it to short circuit) Dalba (talk) 11:37, 17 July 2015 (UTC)

I added a paragraph about the steps for calculating per-unit system into the original "purpose" column.Hsiu Wei Chang (talk) 05:42, 10 December 2015 (UTC)Hsiu-Wei

Apparati?!
In English, the plural of apparatus is apparatuses. If you must be pedantic and insist that it's a Latin word, then get it right. The plural is apparatus, not apparati. It's a fourth-declension noun, not second-declension masculine. See Latin 4th declension

I won't bother editing the article; it'll only get reversed.

109.157.82.217 (talk) 21:08, 5 June 2016 (UTC)
 * Agree and corrected, as in apparatus. Please edit the page yourself next time! --Ita140188 (talk) 10:01, 11 April 2017 (UTC)
 * We used to be taught 'apparata' for the plural version. I reckon - use whatever you (we) like. KorgBoy (talk) 10:57, 15 April 2017 (UTC)

Magnitudes
I seriously believe that one of the very first things to explain to anybody when talking about base impedance, with the label Zbase, is that it is a magnitude. And they need to define it right from the start what exactly is 'Zbase'. For example, is it SQRT(R^2+X^2)? To me, base impedance is one of the most poorly defined parameters (anywhere - not just in power engineering....but just anywhere). The textbooks and resources should all get their act together, and define things properly, and clearly. In fact, they should just say that Vbase, etc are all magnitudes. Not complex-valued quantities. People get confused because - one moment they're learning about phasors and complex quantities, then next minute they get hit with these 'magnitude' values without knowing it. And when somebody tells them they are magnitude values, they remain confused because they don't understand the reasons for it. The issue is not because of the newcomer. The issue is due to whoever started introducing these Zbase, Sbase etc values without clearly telling everybody why they're magnitudes, instead of complex values. KorgBoy (talk) 06:02, 12 April 2017 (UTC)