eeet-241/2-February/2-10_Notes.md

Transformers

R_m is the heat losses in the transformer.

X_m accounts for inperfections in power transfer. R_m>>R_f\ X_m>>X_f\ \therefore\ ignore\ voltage\ across\ R_f\ and\ X_f\ R_m={E_p^2\over P_m}\ S_m=E_p\times I_m\ X_m={E_p^2\over Q_m}\ Q_m=\sqrt{S_m^2-P_m^2} R_p total transformer resistance referred to primary side

X_p total transformer reactance referred to on the primary side

Short the secondary, then: R_p=R_{f_1}+a^2R_{f_2}\ X_p=X_{f_1}+a^2X_{f_2}\ Z_p=\sqrt{R_p^2+X_p^2}\[16pt] Find\ I_p\ and\ P_p\ to\ find\ values\ of\ R_p\ and X_p\[16pt] if\ X_p>>5R_p\ neglect\ R_p

Subtract S from the rating to get the actual usable power