Question

(4b) Two parallel three-phase loads are connected to a three-phase A connected source through a line. The line voltage VAB at the two loads is 200 230° V. One load is configured in Y and absorbs three-phase real power 40KW with a 0.9 leading power factor, and the other load s configured in A with ZA = 12+j150 per phase. Please calculate (a) The line currents (11pts) (b) The power factor at the combined load (3pts) (c) The phase currents in the A connected load (3pts)

Answer 1

e connected source VAB = 2002 30°V A zo Now loads are Steer connected wad 40kw 0.9 Leading Pot Zs= 12 +1152/ph convert zo to stan czy) zý 12+115 ut is a ph 3 Toad vollege per phase VAVAB L-30 डि 200 L30-30 53 sånce be done Van = 115.47 20° volt. source & load is balanced , so calculation can on pen phase basis. IT 1) 12 Van ♡ 115:4720 VYZY zy in stas connection phase current = Line current

load! Now P: 3 VpLpn cost) B = 3 Vpn Ion, Lost 1,2 40 x103 3x115.47 x 0.9 129.3 A cost -0. 30. 25.84 128.3 225.84 1' Pof is leading) So, ī, for load 2 I2 = Vph zt 15:4720 =18.033 L-5134. Amp 4+js Total current So ay line It: T, + 12 = 1 28.3 L 25.84 + 18.033 L-51-34 IT = 133.465 218. 26' Amp current = 133.465A b> Power facton atte to the combined load Pifs cos (18.26) = 0.9496 Ileading). c), phase current in the a connected load. line current of a connected load L2 = 18.0332-81-34-A Phase current (0) - I line 230 = 18.033 L30-51434 1 Phase current col (1260) 10.411 L-21.34* Amp