# Transformer Example Problem

**Kevin Starkey EMEC, Nick Christman, Aric Vyhmeister**

**Problem:**

A step down transformer has a winding of turns. (a) If the input voltage is 1200V, what is the resulting output voltage? (b) If the input and output currents are , respectively, what is the current loss due to the leakage inductance, .

**Solution:**

a) By modifying equation 5-39 (Mohan 5-22) we can obtain an equation for the output voltage. That is,

.

With the information provided we can now determine the output voltage:

b) From the figure above, we need to find the true value of current (i.e. the current that is not lost by leakage inductance). To accomplish this we will use equation 5-40 (Mohan 5-23) to obtain the value of . That is,

.

Now from equation 5-42 (Mohan 5-23) we can obtain the current loss due to the leakage inductance, which is

.

Therefore, the current loss in our transformer is , which means this specific transformer is very "leaky."