A three-phase blanced load connected in Y consumes 3kW(total of the 3 phases) at a power factor of 0.8(-). A balanced Y load of capacitors will be added in parallel so that the power factor of the combination improves to 0.85(-). If the frecuency is 60 Hz and the line-to-line voltages a a balanced set of 200 Vrms, get:
a) The magnitude of the line current IaA that the line consumes before placing the capacitors.
b) The value of the capacitance required by phase in Y
A three-phase blanced load connected in Y consumes 3kW(total of the 3 phases) at a power...
2) The reactive power of the balanced Y-Y connected three phase system depicted below is to be compensated by adding shunt capacitors. The network frequency is known as 50 Hz. The load resistances are R 330ΣΩ and the load inductances are L H. The phasor of the voltage for R phase is given as V 220/2 Volts. a) Find the followings before connecting the power factor compensation capacitors: i) The effective values of the line currents IR, Is, IT, ii)...
b) The load connected to a three-phase supply comprises three similar coils connected in star. If the phase currents are 10A and the total active power and power factor absorb by the loads are 3kW and 0.8 lagging, respectively. Find: i. The magnitude of phase and line voltages (4 marks) ii. Total apparent power (1 mark) iii. The impedance of each coil. (2 marks) c) If the coil in Q3(b) are now connected in delta to the same three-phase supply,...
A Δ-connected source supplies power to a Y-connected load in a three-phase balanced system. Given that the line impedance is (1 + j1) Ω per phase while the load impedance is (6 + j4) Ω per phase, find the magnitude of the line voltage at the load. Assume the source phase voltage Vab= 208 ∠0° V rms. The magnitude of the line voltage at the load is _______ Vrms.
2. Two balanced three-phase loads are connected in parallel. One load with per phase impedance 21 ?, is connected in delta, and the other load has per phase impedance 15 2 and is connected in wye. Ignore the line impedance. If the line voltage is a 208230° Vrms, determine (a) the phase voltage for phase-a, ) the line current Ia*, (c) the phase currents in the delta load (d) the complex power of the load and the power factor.
A three-phase generator connected in star generates a phase
voltage of Vθ = 220 Vrms and supplies a three-phase load also
connected in star. The three phases of the generator are connected
to the three loads shown Remember that the return of the current of
each charge is through the Neutral.
a) Calculate the phase, line, load and neutral currents
b) Calculate the phase, line and load voltages
c) Calculate the powers of Apparent (S), Real (P) and Reactive (Q)...
1. The phase voltage at the terminals of a balanced three-phase Y-connected load has an amplitude of 120V. The load has an impedance of 39 + j28Ω per phase. It is fed from a line having an impedance of 0.8 + j1.5 Ω per phase. The Y-connected source at the sending end of the line has an internal impedance of 0.2 + j0.5 Ω per phase. Calculate: a) The three line currents b) The three-phase voltages at the load c) ...
A 3-φ Y connected source supplies 12 kVA with a power factor of 0.8 lagging to a parallel combination of a Y load and a Δ load. If the Y load consumes 5.6 kVA at a power factor of 0.75 lagging and has phase-a current of 8 Arms and the angle of the current is -30°, determine the phase impedance of the Δ load. Real part of the impedance of the Δ load in Ohms: Imaginary part of the impedance of the...
5. The line to neutral voltages of a Y-connected three phase source are given by, The above three phase source is directly connected to a delta connected balanced three phase resistive load. The resistance in each phase is 10 ohms. Calculate the current phasor 0. Answer- 4. Following three loads are connected in parallel across a single-phase source voltage source: Load 1 absorbs 15 kW and 6.667 kvar; Load 2 absorbs 3 kVA at 0.96PF leading; Load 3 absorbs 15...
A three-phase positive sequence Y-connected source supplies 14 kVA with a power factor of 0.75 lagging to a parallel combination of a Y-connected load and a A-connected load. The Y-connected load uses 9 kVA at a power factor of 0.6 lagging and has an a-phase current of 102-30° A. a) Find the complex power per phase of the A-connected load. b) Find the magnitude of the line voltage.
The following three-phase, balanced loads are connected across a three-phase, Y-connected 60 Hz source with a line-to-line voltage of 480 V. The loads are described below: • Load 1: ∆-connected, total three-phase apparent power is 30 kVA at 0.95 power factor lagging. • Load 2: ∆-connected, total three-phase active power is 20 kW at 0.7 power factor lagging. • Load 3: Y-connected, phase current is 30 A, and power factor is 0.9 pf leading. (a) Calculate the total complex power...