Question

508 CHAPTER 11 . POLYPHASE CIRCUITS 11.40 In a balanced three-phase system, the source has an aboc phase-sequence and is connected in delta. There are two rallel wye-connected loads. The phase impedance of load i and load 2 is 4 The line impedance connecting the source to the loads is 0.3 + j0.2 2. If the curre IAN! = 10/20-Arms, find the delta currents in the source 4 Ω and 10 +/4 Ω, respectively. nt in the a phase of load 1 is 11.41 An abc-phase-sequence balanced three-phase source feeds a balanced load. The system is connected wye-wye and the load impedance is 16 +j10 Ω, and the total power absorbed by the load is 2000 W. Determine the magnitude of the source voltage Van = 0°. The line impedance is 0.5 0.2 Ω, 11.42 Three equal impedances are delta connected have value of 60 +j30 S2. These are connected to a supply of 230-V rms three-phase circuits. Three equal impedances 40 + j10 each, are wye-connected across the same circuit at the same points. Determine the line current, total complex power supplied to the loads, and power factor of the two loads combined. 11.43 A balanced three-phase source with Vi 240 V rms is supplying 8 kVA at 0.6 power factor lagging to two wye-connected parallel loads. If one load draws 3 kW at dance ner phase of

Answer 1

rected is ditta ads I and 2 aue Stas m mec 2 line = 03io'2 C. 03 Delta efuwalent, 십 Lord, au 12埕12 $21$12 4ピ4 12 2 3013121 otan

tne arent n Ng x phase ausenb L2 . 30ナ$12. -5 ะ 25.93/21.94 25 13147.4 A , 25,93 L92-06 A.

Total pcuve γ abs,bed by Load 2000W о.stjo.2. e phase efivalent diagyam (etJio VanLo Pex phase paver absosbed&oaw Van L o an - 93L 31 12 19, 39

Phase ang behoeen Van ama 31-72 ° Pen phase eal powe 3 Van Iar CoS an cos (372)200o lq. 31 3 3 Van 200 137 3 3 3 Van R3 33

ected 4,1 Load 1 is ked with 2니 suppy evert the ioad also della coecm 120 tỉ3D 1201J30 s consideed

630 22 2Lt 12.0 30 2-S 60t's 30+120+130 230 Lo 43-73 22-1 6 5,.36 L 22 16 A 22+16 i 120 5,26 97-84. Ą 5.36 L-22.16 -12o

Total cem ples paucu (330 o) (526 -22.16 = V3 (230 Lo') (5.26 L 22.16) 2095.44 L2a.16 VA teted emplex ues supplied he deed 寸 : 2095,4니 L22.16 VA Pewer fachoyCos (2216) 0.926 .