Equation explanation

[omglol]

Hello!

I am looking at diode rectifier circuit and the equations about overlap on this page: http://people.ucalgary.ca/~aknigh/vsd/ssim/vsi/co.html

I do not understand certain step - at the point where it is written "Equating the two expressions above":

Va(t) - Vb(t) = - Vll sin (omega t)


Why is it MINUS (-) Vll? Isn't Va(t) - Vb(t) just phase-to-phase voltage, so +Vll?

[Asuka]

Hello!

I am looking at diode rectifier circuit and the equations about overlap on this page: http://people.ucalgary.ca/~aknigh/vsd/ssim/vsi/co.html

I do not understand certain step - at the point where it is written "Equating the two expressions above":

Va(t) - Vb(t) = - Vll sin (omega t)


Why is it MINUS (-) Vll? Isn't Va(t) - Vb(t) just phase-to-phase voltage, so +Vll?

There are many other mathematical errors in the equations and spelling mistakes in that document, so perhaps the author made a mistake here too. Perhaps you could email him and ask about it, he may be glad that someone found a typo for him.

[omglol]

Hello!

I am looking at diode rectifier circuit and the equations about overlap on this page: http://people.ucalgary.ca/~aknigh/vsd/ssim/vsi/co.html

I do not understand certain step - at the point where it is written "Equating the two expressions above":

Va(t) - Vb(t) = - Vll sin (omega t)


Why is it MINUS (-) Vll? Isn't Va(t) - Vb(t) just phase-to-phase voltage, so +Vll?

There are many other mathematical errors in the equations and spelling mistakes in that document, so perhaps the author made a mistake here too. Perhaps you could email him and ask about it, he may be glad that someone found a typo for him.

Hi! Thank you for your reply. Could you point out the mistakes for me? I don't dare to correct something I do not understand fully.

[Asuka]

Could you point out the mistakes for me? I don't dare to correct something I do not understand fully.

For example,

It becomes necessary to fund the power in the motor, then the power in the dc link and to solve

should be "find". If you don't dare to correct things though, a better approach might be to just ask a question to him.

[omglol]

I mean mathematical mistakes, not spelling ones ...

[Asuka]

I mean mathematical mistakes, not spelling ones ...

For example, in the first integral on that page, the limits of integration are from zero to gamma, but the integrand is dt. It should be d(omega t) or better d(theta) or something, since gamma is not a time but an angle. Then he has fudged the error in the next line with the result of the integral.

A wise man once said: Where there are spelling errors, there are other errors.