Q1. The equivalent resistance and equivalent reactance (high side) for a 37.5 kVA, 2400-600 V, 60 Hz transformer are 2.82 and 62, respectively. If a load impedance of 10 2 is connected side, [6] (i) The equivalent input impedance of the transformer and to the low determine: load combination (ii) The primary current, if 2400 V is supplied to the primary and (iii) The voltage across the load

Q1. The equivalent resistance and equivalent reactance (high side) for a 37.5 kVA, 2400-600 V, 60 Hz transformer are 2.82 and 62, respectively. If a load impedance of 10 2 is connected side, [6] (i) The equivalent input impedance of the transformer and to the low determine: load combination (ii) The primary current, if 2400 V is supplied to the primary and (iii) The voltage across the load

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

Chapter13: Transmission Lines: Transient Operation

Section: Chapter Questions

Problem 13.24P

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An infinite bus, which is a constant voltage source, is connected to the primary of the three-winding transformer of Problem 3.53. A 7.5-MVA,13.2-kV synchronous motor with a sub transient reactance of 0.2 per unit is connected to the transformer secondary. A5-MW,2.3-kV three-phase resistive load is connected to the tertiary Choosing a base of 66 kV and 15 MVA in the primary, draw the impedance diagram of the system showing per-unit impedances. Neglect transformer exciting current, phase shifts, and all resistances except the resistive load.
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A single-phase 100-kVA,2400/240-volt,60-Hz distribution transformer is used as a step-down transformer. The load, which is connected to the 240-volt secondary winding, absorbs 60 kVA at 0.8 power factor lagging and is at 230 volts. Assuming an ideal transformer, calculate the following: (a) primary voltage, (b) load impedance, (c) load impedance referred to the primary, and (d) the real and reactive power supplied to the primary winding.
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