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A balanced Y-connected voltage source with
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Power System Analysis and Design (MindTap Course List)
- Question #1: The following unbalanced line-to-ground voltages are applied to the balanced Y-load shown in the following figure: C a + Vea ag ell + T, Figure 1: Balanced Y-load supplied by an unbalanced voltage source. Vag = 10020°, Vpg = 754180°, and Veg with neutral impedance Zn = j1 n. 50290° volts. The Y-load has Zy = 3 + j4 N per phase Calculate the line currents Ia, Ib, and I, using symmetrical components.arrow_forwardThis wind farm needs a 250 km connection laid to Sommerville. The choice is either a 3 phase system or a bipolar dc system at 400 kV and ±400 kV at the receiving end respectively. (i) The 3-phase system has resistive losses per phase of 0.1 Ω/km. Calculate the system losses (in watts) when delivering 0.8 GW. (ii) The bipolar dc system has resistive losses of 0.1 Ω/km. Calculate the system losses (in watts) when delivering 0.8 GW. (iii) Calculate the efficiencies of the two systems. (iv) Comment on which system you would choose to use and why.arrow_forwardThree 230V single phase loads are supplied from a 400V 50Hz 3 phase 4 wire supply. The loads supplied are as follows a. 10Kw at a unity power factor connected between L1 and neutral. b. 15 kVA at 0.8 lagging power factor connected between L2 and neutral. c. 8kVA at 0.7 lagging power factor connected between L3 and neutral. Calculate a. The current in each line conductor. B. The current in the neutral conductorarrow_forward
- a) A 415 V mains supplies a star-connected load at 50 Hz. Each branch of the load is a resistor of 24 Ω. Using 415 V and 20kVA bases calculate the following:i) Base impedance [EV3]ii) Base current [EV3]iii) Per unit load resistance [EV3]iv) Per unit current [EV6]v) Per unit power [EV3] b) Statei. Two advantages of per unit notation [AP4]ii. Three advantages of three phase system over single phase system [AP3]arrow_forwardA single phase a. C distributor AB 300mts long if fed from end A is loaded as under a) 100amps at 0.707 p.f lagging 200mts from pointA(b) 200amps at 0.8p.f lagging 300mts from point A. The total resistance and the Reactance and the distributor is0. 2ohms and0. 1ohms per km respectively. Calculate the total voltage drop in the distributor. The load power factors refer to the voltage at the far endarrow_forwardIn the circuit of figure shown in the next slide, threeimpedances are 12 – j10 ohms, 10 + j20 ohms, and 15 + j0ohms, connected between conductors a, b, c and the neutral“n” of a balanced 230 volts, 60 hertz, 3 phase, 4 wire, ABCsystem. Using Van as the reference vector, determine:a. Current in each impedanceb. Neutral current Inc. Readings of wattmeters W1, W2, & W3d. Power in each impedance ..arrow_forward
- Two balanced Y-connected loads in parallel, one drawing 15 kW at 0.6 power factor lagging andthe other drawing 10 kVA at 0.8 power factor leading, are supplied by a balanced, three-phase,480-volt source.a. Draw the power triangle for each load and for the combined load.b. Determine the power factor of the combined load and state whether lagging or leading.c. Determine the magnitude of the line current from the source.arrow_forward11. A 3-, 400-V symmetrical supply feeds a star-connected load consisting of non-reactive resistors of 3, 4 and 5 connected to the R. Y and 8 lines respectively. The phase sequence is RYB. Calculate (1) the load star point potential (i) current in each resistor and power dissipated in each resistor. (i)34.5 V (ii) 664 A, 59.7 A. 51.8 A (iii) 13.22 kW, 14.21 kW, 13.42 kW) Answer Need Asap will surely upvotearrow_forwardThree unequal single-phase loads are connected across the lines of a balanced, 3-phase, 230 volts (line) circuit. The first load takes 106 A at 0.78 pf lagging and is connected across lines 1 & 2. The second load takes 142 A, at 0.82 pf lagging and is connected across 2 & 3. The third one takes a load of 28.4 kW at 0.77 pf lagging. Solve for the following a. The line currentsb. The equivalent wye connected impedance of the connectionc. The total complex power absorbed by the loadarrow_forward
- A 3-phase RYB sequence, 4-wire distributor supplies a balanced line-neutral voltage of 230 V to the Y connected loads: Phase R: 20KW, unity power factorPhase Y: 24.89 KW, 0.866 laggingPhase B: 24.89 KW, 0.866 leadinga) Calculate the current in each line.b) Clearly draw the voltage and current phasor diagram.c) Calculate the current in the neutral.arrow_forwardA current is measured at the neutral ground of a star load, of equal impedances in all three phases. Which of the following conditions is NOT possible?A) The currents in the three phases are equal in magnitude and angle.B)One phase of the supply conductors was left in open circuit.C) The line-to-neutral voltages in the load are equal in magnitude and with 120° phase shifts between them.D) None of the abovearrow_forwardA 210V, 50 Hz, single phase radial distribution system, the resistance of the wire is 0.0008 ohm/m supply and return. Two loads are connected and it consumes 20 and 15 A respectively and are fed from the cable at distance of 25 and 10 respectively. Calculate the voltage available across load 1 and 2. a- Voltage across load A is, Va= b- Voltage across load B is, Vb=arrow_forward
- Power System Analysis and Design (MindTap Course ...Electrical EngineeringISBN:9781305632134Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. SarmaPublisher:Cengage Learning