10.26.2004 Homework 5
Randall Robert 9771
Problem 1 Calculate the parameters of a 20kVA, 480/120V transformer equivalent model recalculated to the primary side, if the short circuit voltage is VISC=7% ovV1r, shortcircuit power Psc=2.5% of Sr, open circuit
INTRODUCTION
Elements of power system:
Generating Station
High-voltage transmission system and low-voltage distribution system
Load
Detailedelectricpowersystem
Electromechanical energy conversion
Devices for continuous energy conversion:
Motors: conve
Homework 06 November 21, 2004
Randall Robert 9771
Problem 1. Calculate RMS values of the line currents as well as the active an reactive powers in the circuit shown in Fig. 1, assuming that the load is supplied with a symmetrical voltage such that u R = 1
EE 3410 HOMEWORK #1 1.a)
Randall Robert
The circuit parameters are R1=2.5; R2=1.5; L2=1.5; C1=0.8S Active power P=(1/T) 0t p(t)dt = UI*cos() For resistors, there is no phase shift so there is no reactive power, only active. UR2= (R2/(R2=L2)U = (1.5/3)*240
Homework #2 10.10.04 Problem 1. Parameters: LOAD; VRMS = 480V P = 10kW pF = 0.5 or 0.9 SOURCE; SSC = 0.25[MVA] Xs/Rs = = 2
Randall Robert 9771
Variable of interest is VRMS of the source which is noted E, and the loss of active power Ps in the supply. Firs
Homework #3 10.19.4
Randall Robert 9771
Problem 1. Distribution voltage RMS value measured at unloaded bus is E = 2.4kV, its short circuit power ia 1MVA and the reactance to resistance ratio = 2. Calculate the load voltage RMS value V, power loss in the s
Homework #4 10.23.4 Problem 1
Randall Robert 9771
An inductor has a magnetic core with relative permeability of =8000, cross-section A=25cm and the length of the magnetic path l=50cm. The inductor is to operate at 240VRMS. Calculate the number of the coil
Example 1
°Assume VS =100V, Rload =1 Ohm, and Rwire =0.5 Ohm. Determine
a) Voltage at the load side
b) Percentage of the load voltage with respect to the source voltage
c) Energy consumed by the load during a 10-hour period in Joules
d) Efﬁciency during a