Design a three$-$phase, oil$-$immersed $Y-$ power transformer with a rating of $75$ kVA $,11k\frac{V}{400}V,50Hz,$ using the core material specified in Question $1.$ To do this, calculate all the dimensions labeled in Figure $1,$ given that H $1$ is $24\mathrm{.}6$ cm and the air gap is $1$ cm $.$ The winding is made of copper and the current density chart is given in Appendix $1.$ Next, calculate the copper losses per phase, assuming typical values for copper density and resistivity. Suitable value for Kt is also provided in the Appendix $2.$

FIGURE $1$

$(50\%)$