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  There are three monophasic transformers of 500 kva, 66000/400v that have a shirt circuit relative impedence of 0.01 + j0.065 per unit and a loss in the vacuum test of 4.2kva with cos theta = 0.84 inductive form a substation of 66 kv by means of a line 12+ j30ohm of impedance
•  1) calculate the impedance of the load in ohms 
• 2) calculate the primary and secondary voltage and the performance of the bank of transformers under these conditions
•  3) obtain the permanent short circuit current of the low voltage side of the bank.      

Answer rating: 100% (QA)

Sol b a J where z base Isc I sec I sec Impedence in ohms is Zeq Zeq pu Zbase 3 Vabase Shase 3 ... View the full answer