Transformers, Electrical Engineering

Three transformers are provided with the following rating values:

1) 2400/240 V, 55kVA, Req1 = (0.1 + 0.0Y) Ohm and Xeq1 = (0.15 + 0.XX) Ohm.

2) 240/120 V, 25kVA, Req1 = (0.15 + 0.0Y) Ohm and Xeq1 = (0.30 + 0.XX) Ohm.

3) 240/120 V, 20kVA, Req1 = (0.20 + 0.0Y) Ohm and Xeq1 = (0.40 + 0.XX) Ohm.

All impedances are referred to the 240 V side. Transformer no. 1 can be operated as an autotransformer (Notice; the equivalent impedance as an autotransformer is calculated by dividing the original impedance over the turn's ratio of the autotransformer).

A 240 V, 60 kW, 0.9 power factor lagging load is to be supplied by the above transformers. The load will be connected for one full week, and the energy cost is 0.10 SR / kWh. As it can be observed, the load has to be supplied by a combination of the transformers. Assume that both 2640 V and 120 V supplies are available.

Determine the best design (best combination) to supply the load so that the operating cost is minimum. Show all the steps in your calculation.

Note:

 "XX" is the 7th and 8th digit of student ID, like (200891XX0).

"Y" is your section number (e.g., 01, 02).

Posted Date: 2/20/2013 1:07:03 AM | Location : United States







Related Discussions:- Transformers, Assignment Help, Ask Question on Transformers, Get Answer, Expert's Help, Transformers Discussions

Write discussion on Transformers
Your posts are moderated
Related Questions
what is a transformer?

PN Diode The current-voltage characteristics are of major concern in the learning of semiconductor devices with light entering like a third variable in optoelectronics devic

State Kirchoff's Current Law Kirchoff's Current Law (KCL) describes at any junction in an electric circuit the total current flowing towards that junction is equivalent to th

Explain different stage in energy audit?

Logistical management - Gis applications: Using GIS also allows a radical improvement in daily work management practices - such as planning new installations, scheduling opera

Q. Working of self - excited generators? For self-excited generators, residual magnetism must be present in the ferromagnetic circuit of the machine in order to start the self-

Armature Winding In this  winding the working  emf is induced by the working  flux. The current  which is  dependent on the load  called current.  The windings  that handle

(a) In the so-called folded binary code of 4 bits, the left most digit represents the sign of an analog signal's quantized samples (with 0 for negative and 1 for positive), and the

design a clipper circuit of a sinsoiudial wave of a peak value 25v&minimum value of -12v to make the output voltages of 20&-9v respectively.

Q. Process of Amplitude Modulation? In AM the message signal is impressed on the amplitude of the carrier signal. There are several different ways of amplitude modulating the c