Web Application for Symmetrical Componets: http://personal.strath.ac.uk/steven.m.blair/seq/
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Okay. Now, a few things to keep in mind is that these A operator only works for the ABC phase sequence. That totally makes sense from a visual perspective as well. It's only for the ABC phase sequence, but if you have an ACB phase sequences, these A operators are going to be different.
Let's just go over that really quickly. Now, we're not talking about ABC anymore, now we're talking about ACB. What would we have to do with this phase or diagram? Well, to be an ACB phase sequence, we have to change that to IC. Then we have to change that to IB, right? Now, this is an ACB phase sequence.
Now, we see that things are a little bit different. IA still at zero degrees, but IB, it's at 120 degrees with respect to the reference line. IB, it's not negative anymore, it's just the 120 degrees. Then IC, now we see that IC is at 120 degrees in the opposite direction. Now, we have to add a negative sign there, which means the way that we've defined these guys here is going to be different.
IA stays where it is, but look at IB now. IB, we only have to shift IA 120 degrees to get it equal to IB. With IA, we only have to shift IA 120 degrees and we'll get IB, so we don't have that two anymore. Then same thing with IC, we have to shift it 240 degrees in the counter clockwise direction. 240 degrees. We have to shift IA 240 degrees in the counter clockwise direction, which means we have to use the A superscript two operator.
For an ABC system, the operator is that, but this won't work for an ACB system. What we have to do is we have to put a superscript two there. Now, this totally makes sense for an ACB phase sequence. This is how we have to define IB and IC with respect to IA using the A and A superscript two operators.
I hope this wasn't too confusing, but it's very intuitive once you see the big picture. Now, if you find this video useful, please go ahead and click on the bottom right corner of the screen to subscribe. In part three, we're going to take this concept of the A operator and apply it to the positive and negative sequence components and then look at the benefits of it. This video was brought to you by generalpac.com, making power systems intuitive.