A 6.6 kV/350 kV, 350 kVA, 50 Hz testing transformer when tested had the following observations: (a) No load voltage rise on HV side was 1% more than the rated value when 6.6 kV was applied on primary side. (b) The rated short circuit current was obtained on HV side when shorted with 8% rated voltage on primary side. Calculate (i) self-capacitance of transformer along with its HV side bushing, and (ii) leakage reactance neglecting resistance

A 6.6 kV/350 kV, 350 kVA, 50 Hz testing transformer when tested had the following observations: (a) No load voltage rise on HV side was 1% more than the rated value when 6.6 kV was applied on primary side. (b) The rated short circuit current was obtained on HV side when shorted with 8% rated voltage on primary side. Calculate (i) self-capacitance of transformer along with its HV side bushing, and (ii) leakage reactance neglecting resistance

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.1P: (a) An ideal single-phase two-winding transformer with turns ratio at=N1/N2 is connected with a...

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A two-winding single-phase transformer rated 60kVA,240/1200V,60Hz, has an efficiency of 0.96 when operated at rated load, 0.8 power factor lagging. This transformer is to be utilized as a 1440/1200-V step-down autotransformer in a power distribution system. (a) Find the permissible kVA rating of the autotransformer if the winding currents and voltages are not to exceed the ratings as a two-winding transformer. Assume an ideal transformer. (b) Determine the efficiency of the autotransformer with the kVA loading of part (a) and 0.8 power factor leading.
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