Transformer equivalent impedance A singlephase ideal transfo

Transformer, equivalent impedance

A single-phase ideal transformer has the following ratings: 100 kVA, V_primary = 200 V, V_secondary = 1000 V, f= 60 Hz. A resistance load of 250 Q is connected across the secondary. Compute the equivalent impedance of the load, Z\'_load, seen by the source connected to the primary of the transformer.

Solution

primary voltage=200 volts

secondary voltage=1000 volts

f=60 hertz

secondary side load impedance=250 ohms

transformation ratio k=(N2/N1)=(V2/V1)=(I1/I2)

so k=(v2/v1)=1000/200=5

for calculation purpose secondary side voltage is shifted to primary side it become=v2/k

so v2\'=v2/k=1000/5=200 volts

the secondary side impedance is shifted to primary side it becomes=zl/k^2=250/k^2=250/25=10 ohms