A 10kVA, 200/400V 50Hz single-phase transformer gave the following test results. O/C test: 200V, 1.3A, 120W, on l.v. side. S/C test: 22V, 30A, 200W on h.v. side.
(a) Calculate the magnetizing current and the component corresponding to core loss at normal frequency and voltage.
(b) Calculate the magnetizing branch impedances.
(c) Find the percentage regulation when supplying full load at 0.8 p.f. leading.
Determine the load which gives maximum efficiency, and find the value of this efficiency at unity power factor.