Assume that a substation supplies three different kinds of loads, mainly, incandescent lights, induction motors, and synchronous motors, as shown in Figure 8.12. The substation power factor is found from the total reactive and real powers of the various loads that are connected. Based on the given data in Figure 8.12, determine the following: a. The apparent, real, and kvars of each load b. The total apparent, real, and reactive powers of the power that should be supplied by the substation c. The total power factor of the substation Substation 4 3 Σinendesent lights (100 KVAE 10 PF) Einduction motor P loads (300 kVAe 0.85 PF lag) Esynchronous motor P loads (200 kVAe 0.8 lead) (a) P3= 160 kW P = 100 kW 5 Sz= 300KVA 8 ka P = 255KW (b) Sut = 516.4 kVA Que = 38 kvar Pot - 515 kW (c) FIGURE 8.12 For Example 8.2: (a) connection diagram, (b) phasor diagrams of individual loads, and (c) phasor diagram of combined loads. 24 Q- 120kvar

Assume that a substation supplies three different kinds of loads, mainly, incandescent lights, induction motors, and synchronous motors, as shown in Figure 8.12. The substation power factor is found from the total reactive and real powers of the various loads that are connected. Based on the given data in Figure 8.12, determine the following: a. The apparent, real, and kvars of each load b. The total apparent, real, and reactive powers of the power that should be supplied by the substation c. The total power factor of the substation Substation 4 3 Σinendesent lights (100 KVAE 10 PF) Einduction motor P loads (300 kVAe 0.85 PF lag) Esynchronous motor P loads (200 kVAe 0.8 lead) (a) P3= 160 kW P = 100 kW 5 Sz= 300KVA 8 ka P = 255KW (b) Sut = 516.4 kVA Que = 38 kvar Pot - 515 kW (c) FIGURE 8.12 For Example 8.2: (a) connection diagram, (b) phasor diagrams of individual loads, and (c) phasor diagram of combined loads. 24 Q- 120kvar

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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