# Homework Help: Three-phase system analysis

1. Feb 11, 2016

### Frank-95

1. The problem statement, all variables and given/known data

In the following three phase system, calculate the current in the middle capacitor:

2. Relevant equations

I = V/Z

ZY = ZΔ / 3

3. The attempt at a solution

Hello! I'm trying to figure out a method for solving any generic three phase system. In particular, I found very effective method the single phase analysis, by reducing generators and loads to star loads (if they are originally delta loads). I don't know if this can always be done, and I have some doubts about parallel loads.

As regards this particular system, I converted the delta load to a star load, so:

R2Y = R2Δ / 3

Capacitors are already disposed in a star load. So I consider the following single phase system:

(R2 and R1 are switched here, I apologise)

Is that the right equivalent single phase system?
If this is right, I would just need to calculate equivalent impedance, find the first phase current, and add -120° to find the middle one right?

If that is not right, where I mistakened? Thanks :)

2. Feb 16, 2016