1 Phase, 3 Phase

Addition of Vectors is different from normal addition like addition of numbers

I am trying to explain further the point raised by PWSlack in his reply.

In a three phase system we have three vectors say

V = Va + Vb +Vc

Va= Vo e^(j. 0)

Vb= Vo e^(j. 2pi/3)

Vc= Vo e^(j. 4pi/3)

Now Phase to Phase Voltage =Vab= Va - Vb=?

Vab= Vo [ {cos(0) +jsin(0)} - {cos(2 .pi/3) +j sin (2.pi/3)} ]

Vab= Vo [{1} - {-1/2 +j (square root 3)/2}]

Further solving gives the result as

Vab =Vo (square root 3)

So where we have Phase to neutral voltage 230 V we have

Vab = 230 * 1.732 = 400 V

As Vectors are involved so it is 400V instead of 460 V.