Wye and Delta and Combination Circuits

Wye & Delta Connection and Combination Circuits. What is the first thing that comes to your mind when you hear these? Well, let me tell you mine - Connections! Yes, connections were our topic for the week and as promised, we will share with you our learnings here in our blog.


Combination Circuits - A connection of a circuit that can either be a series or a parallel connection that are combined.

Wye and Delta Connection - A connection that is neither a parallel nor a series connection.


Now, we will focus first on combination circuits then the latter.

Combination circuit (notice the presence of series and parallel connections)

Process:

1. Find Req of both series and parallel connections
2. Find total resistance
3. Find current voltage

We ought to find the total resistance so the process would be combining the series and parallel connections or also known as the "resistance equivalent". The R2 and R3 are connected in a series connection, thus, we are able to add the two resistors to find the resistance equivalent.

(Refer to the previous article for the formulas)

Req = 8Ω + 4Ω = 12Ω

We have one series connection and two parallel connections which are 6Ω and two 12Ω, respectively. Next process is to obtain the resistance equivalent of the two parallel resistors.

1/Req = 1/12Ω + 1/12 Ω = 6Ω

Now we have two series connected resistors and these two can be summed up to arrive to the Req of the whole circuit.

Req = 6Ω + 6Ω = 12Ω

Last thing we do is to find the current flowing through the circuit by using Ohm's Law (you can also apply KVL and KCL, whichever you find easy).

i = V/R

i = 12V / 12Ω

i = 1 ampere

As long as you understand the illustration and know the formula, it will be as easy as eating - no sweat plus, you enjoyed!

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The Wye connection joins together one end of each of the coils and applies the individual phases to the open ends. These two connections produce very different results when power is applied.

An advantage of the Delta connection is it has a higher reliability. If one of the three primary windings fails, the secondary will still produce a full voltage on all three phases.

(to be continued...)