Problem
The primary winding of the step-down transformer is
The relationship between the ideal transformer voltage (U) and the number of turns (n) is:
U1/U2=n1/n2;
The relationship between the ideal transformer current (I) and the number of turns (n) is:
I1/I2= n2/ n1.
When U1<U2, n1<n2, it is a step-up transformer;
When U1>U2, n1>n2, it is a step-down transformer.