Following from Jonathan's post #99
Transformer Inrush - Open Electrical
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Following from Jonathan's post #99
Transformer Inrush - Open Electrical
Good article, but they could have expressed the final equation more clearly to demonstrate their point. Also, it's a bit pointless to solve the differential equation using Laplace transforms when you can trivially separate the variables. This is how I did it:Quote:
Originally Posted by EddyCurrent
From Faraday's law:
.
Seperate variables:
.
Use sin(A+B) identity to make it easy to integrate:
.
Integrate:
.
Use cos(A+B) identity to simplify:
. (1)
When the transformer is switched on, we have the initial condition relating to the residual flux:
.
So substitute this in to (1) to find constant, k:
.
So the solution is:
.
So now it's easier to see that the . term is a constant, which introduces a DC offset that disappears when the switching angle is . ... i.e at the peak voltage.
I used to like Laplace transforms but that was 40 years ago, I've never needed to use them since :hysterical:
I much prefer the Lapdance performs. . Makes me constant, which introduces a DC offset that disappears when the switching angle is ...at the peak. .:whistle:Quote:
Originally Posted by EddyCurrent