A generation station of 3 MW supply a two regions A & B .The line losses are neglected and the load variation of these regions is as follow: Region A (Time) 11 a.m From 11 a.m to 6 p.m No-load From midnight to From 5 a.m to From 8 a.m to Load (kw) 5 a.m No-load 8 a.m 1200 800 Region B (Time) From From midnight to 6 a.m to 3 p.m to 7 p.m to 6 a.m 3 p.m 7p.m 9 p.m Load (kw) 400 900 No-load 1800 From From From 6 p.m to midnight 600 From 9 p.m to midnight 200 1-Plot The daily load curve of the total system. 2-Find the load factor, diversity factor,plant user factor and the actual generation by the station in kwh in the day for the total system.

41. Two ac sources feed a common variable resistive load as shown in figure. Under the maximum power transfer condition, the power absorbed by the load resistance R, is lall 6 2 j8 2 6 2 11020 ( 0706 O9020° (a) 2200 W (b) 1250 W (c) 1000 W (d) 625 W

4) Therenin's Equinlena Circuit and Marimum Poer truns fer Thiorem a) For the Circuit derive the given in the figure, therenin's eq uivalence Circuit acrass the branch witn the loud impedanu. b) Culculate to deliver the volue of the load Impedanca makimum power to the load, c) caleula te the Power dissipa ted through the loud, 72

es and efficiency at half load

3) Calculate the currents I1, I2 and I0, as well as the active power supplied to the load secondary side.

Three load units A, B and C are connected in parallel and take currents that are respectively 12, 10 and 15 amperes. Assuming IA to be the reference phasor, IB leads IA by 30°, and IC lags IA by 65°, calculate the total current and the angle it makes with the reference.

The figure shows a 3-phase bala Time left 1:06:30 200 /00 Vrms. sequence electrical system. Vcn Vbn %3D al Balanced (-) sequence 100 so a 2000 Vms Select one: O a. 200 /-120 Vrms O b. 200 v2 /0 Vrms O C. 200 /0 Vrms O d. 200 v2/-120 Vrms e. 200/120 Vrms

A single-phase, 120V(rms),60Hz source supplies power to a series R-L circuit consisting of R=10 and L=40mH. (a) Determine the power factor of the circuit and state whether it is lagging or leading. (b) Determine the real and reactive power absorbed by the load. (c) Calculate the peak magnetic energy Wint stored in the inductor by using the expression Wint=L(Irms)2 and check whether the reactive power Q=Wint is satisfied. (Note: The instantaneous magnetic energy storage fluctuates between zero and the peak energy. This energy must be sent twice each cycle to the load from the source by means of reactive power flows.)

Let a 100V sinusoidal source be connected to a series combination of a 3 resistor, an 8 inductor, and a 4 capacitor. (a) Draw the circuit diagram. (b) Compute the series impedance. (C) Determine the current I delivered by the source. Is the current lagging or leading the source voltage? What is the power factor of this circuit?

What will be the value of the twiddle factor: W42