QUESTIONTwo identical transformers have the following information on their name plates:Z = (1.5+j8.5)%50 MVA;50 Hz;66/11 kV;ONAN;Yd11;The core losses are equal to 1% of the rated power.The two transformers are connected in parallel and supply a total load of (64 + j48) MVA.a) Explain the meaning of the following terms found on the name plate of the transformer.50 MVA66/11kV50 HzONANyali(11)(b) Sketch the phasor diagrams for the voltages on the high-voltage side and the low-voltageside of each transformer and sketch the corresponding connection diagram.c) Calculate the efficiency of each transformer.(d) A delta-connected capacitor bank is connected in parallel with the load to improve thepower factor to unit. Calculate the capacitance required per-phase to achieve this.Calculate the efficiency of each transformer when the power factor is unit.Failure of one transformer leads to it being replaced by a 100 MVA, 66/11 kV, 50 Hz transformerwith an impedance of (1.2 + j8.0) %. This is done to increase the load supplied by the paralleledtransformers.Calculate the load on each transformer if the total load supplied by the two transformers is120 MVA at a power factor of 0.85 lagging.g) Calculate the power factor if the capacitor bank calculated in part (d) is connected inparallel with the new load.

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Two identical transformers have the following information on their name plates: 50 MVA; 66/11 kV; 50 Hz; Yd11; ONAN; The core losses are equal to 1% of the rated power. The two transformers are connected in parallel and supply a total load of (64+ j48) MVA. a) Explain the meaning of the following terms found on the name plate of the transformer. ( 50 MVA (11) 66/11kV 50 Hz ONAN Yali Z = (1.5+j8.5)% (iv) (v) (b) Sketch the phasor diagrams for the voltages on the high-voltage side and the low-voltage side of each transformer and sketch the corresponding connection diagram.

Two identical transformers have the following information on their name plates: 50 MVA; 66/11 kV; 50 Hz; Yd11; ONAN; The core losses are equal to 1% of the rated power. The two transformers are connected in parallel and supply a total load of (64+ j48) MVA. a) Explain the meaning of the following terms found on the name plate of the transformer. ( 50 MVA (11) 66/11kV 50 Hz ONAN Yali Z = (1.5+j8.5)% (iv) (v) (b) Sketch the phasor diagrams for the voltages on the high-voltage side and the low-voltage side of each transformer and sketch the corresponding connection diagram.

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 3.64P: The per-unit equivalent circuit of two transformers Ta and Tb connected in parallel, with the same...

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