Example 3.5 Three single-phase transformers are connected in A-A to provide power for a three-phase wye- connected 200 kVA load with a 0.80 lagging power factor and an 80 kVA single-phase light load with a 0.90 lagging power factor, as shown in Figure 3.43. TAC I, BO 0.90 PF FIGURE 3.43 For Example 3.5. Application of Distribution Transformers 133 Assume that the three single-phase transformers have equal percent impedance and equal ratios of percent reactance to percent resistance. The primary-side voltage of the bank is 7,620/13,200 V and the secondary-side voltage is 240 V. Assume that the single-phase transformer connected between phases b and c is rated at 100 kVA and the other two are rated at 75 kVA. Determine the following: The line current flowino in each seconda "A*

Example 3.5 Three single-phase transformers are connected in A-A to provide power for a three-phase wye- connected 200 kVA load with a 0.80 lagging power factor and an 80 kVA single-phase light load with a 0.90 lagging power factor, as shown in Figure 3.43. TAC I, BO 0.90 PF FIGURE 3.43 For Example 3.5. Application of Distribution Transformers 133 Assume that the three single-phase transformers have equal percent impedance and equal ratios of percent reactance to percent resistance. The primary-side voltage of the bank is 7,620/13,200 V and the secondary-side voltage is 240 V. Assume that the single-phase transformer connected between phases b and c is rated at 100 kVA and the other two are rated at 75 kVA. Determine the following: The line current flowino in each seconda "A*

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.26P: A bank of three single-phase transformers, each rated 30MVA,38.1/3.81kV, are connected in Y- with a...

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