Concept explainers
A three-phase line with an impedance of
Load 1: Absorbs a total of 150 kW and 120 kvar.
Load 2: Delta connected with an impedance of
Load 3: 120 kVA at 0.6 PF leading.
If the line-to-neutral voltage at the load end of the line is 2000 v (rms), determine the magnitude of the line-to-line voltage at the source end of the line.
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Chapter 2 Solutions
Power System Analysis and Design (MindTap Course List)
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- A Y-connected balanced three-phase source is connected to a three-phase balanced load through a four-wire three-phase cable. The generator has an impedance of 0.1+j0.3 Q/phase. Each phase of the cable has an impedance of 2+2j 2 The phase "B" load voltage is 102-140° kV. The impedance of each phase of the Y-connected load is 3-j5 Q/phase. For a negative sequence: 1- tto pointe) Calculate "terminal" phase voltage of phases "a" and "c" of generator. 2- E points] Calculate Vab and Vca across the load. 5 points Calculate three phase power supplied by the source. 4- 10 point] Calculate three phase power losses.arrow_forwardThe plant capacity of a 3-phase generating station consists of two 8 MVA generators of reactance 14·5%each and one 4 MVA generator of reactance 9·5%. These are connected to a common bus-bar fromwhich loads are taken through a number of 3 MVA step-up transformers each having 4% reactance.Determine the MVA rating of the circuit breakers on (i) L.V. side and (ii) H.V. side. Reactances givenare based on the MVA of each equipment. [(i) 15·24 MVA (ii) 50·25 MVA]arrow_forwardA three-phase system has balanced conditions so that the per-phase circuit representation can be used as shown in Figure 1 Select the turns ratio of the step-up and step-down transformers that the system operates with an efficiency greater than 99 percent. Moreover, find the complex power (received or given) of all components in the circuit and the V1 and V2 voltages. The load voltage is specified as 4 kV rms, and the load impedance is 4/3 ohm. ..arrow_forward
- Power System Analysis and Design (MindTap Course ...Electrical EngineeringISBN:9781305632134Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. SarmaPublisher:Cengage Learning