A 3000/200V, 50Hz, single phase transformer has a cross sectional area of 150 cm2 for the core. If the number of turns on low voltage winding is 80, determine the number of turns on high voltage winding and maximum value of flux density in the core. -

Given:

$E1= 3000V \\ E2=200V \\ F= 50Hz \\ A=150 cm^2 = 140 * 10-4 m^2 \\ N2= 80 \\ Solution: E_2/E_1= N_2/N_1 \\ 200/3000 = 80/N_1 \\ ∴ N_1 = 1200 \\ E_1= 4.44 fфmN_1= 4.44 fBMAN_1 \\ ∴ 3000= 4.44 * 50* BM * 150* 10-4 * 1200 \\ BM = 0.76 Wb/m^2$