E8-UEE-14 A 3 Phase, 6kV Electric Induction motor, rated at RanInt#(1800,2000) kVA is supplied through a...

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E8-UEE-14 A 3 Phase, 6kV Electric Induction motor, rated at RanInt#(1800,2000) kVA is supplied through a 80m XLPE Cable, manufacturer Type M2NB, M2AB in Trefoil configuration. The details are attached. The power factor of this motor is 0.7 lagging. PART A (a) Write down the Rated kVA and kW of the Motor (b) Select a suitable cross section of the Cable (c) Determine its resistance and reactance and present this on a drawing (d) Determine the Voltage at the Supply End and Voltage drop in Voltage Magnitude and Efficiency in Per Unit (e) It is decided to reduce the cable voltage drop through a capacitor in series with the cable which will cancel out line reactance. Determine the value and KVAR rating of the capacitor and redo the voltage drop calculation. Comment on the result. PART B (a) S=P+jQ: Present this in a Power Triangle. (b) Discuss the benefits a techniques of power factor correction. (c) Show that the KVAR correction formula can be presented as: AKVAR= P(tan-tan (₂) (d) It is required to correct the power factor of the above motor from 0.7 to 0.9 power factor lagging. Calculate the value of capacitance of the capacitor and its KVAR. (e) Calculate the voltage drop and efficiency when both voltage drop and power factor correction are effected. 3.6/6 (7.2) KV-SINGLE CORE, XLPE INSULATED, PVC SHEATHED, SCREENED, UNARMOURED CABLES Type M2N, M2A - Conforming to IEC 60502-2 DIMENSIONAL CHARACTERISTICS Nominal Radial Thickness of Nominal Diameters Inner Outer cross section Indation Sheath Sheath Conductor Insulation Overall mm³ 10 16 25 35 mm 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 50 70 95 120 150 185 240 2.6 300 2.8 400 3.0 500 3.2 630 3.2 800 3.2 1000 3.2 Nominal cross section mm 14 1.4 1.5 7.15 13.15 19 8.3 1.6 10.0 16.0 1.7 11.8 17.8 1.7 13.3 19.3 1.8 14.8 20.8 1.8 16.55 22.55 29 1.9 18.73 24.93 31 2.0 21.3 27.9 35 2.1 24.1 31.3 37 2.2 27.3 41 34.9 2.3 31.0 39.0 45 2.5 37.1 45.0 2.6 41.6 49.6 ELECTRICAL CHARACTERISTICS 2.5 2.5 1.5 1.6 mm Kg/Km Kg/Km Kg/Km Kg/Km 3.82 9.82 15 90 310 28 245 4.83 10.83 16 142 385 43 285 6.02 12.02 17 224 500 68 350 311 610 95 400 421 755 128 465 608 985 185 Approximative net weight Aluminium cable Copper cable Conductor Cable Conductor Cable DC Resistance at Nominal 20°C 14.3 20 22 24 843 25 1065 500 500 560 500 685 500 1270 256 1530 324 790 500 1820 398 910 500 499 1050 500 2200 2740 638 1280 500 2646 3420 804 1570 500 3460 500 500 27 1307 1640 2098 4280 1051 1870 5300 1325 2280 6700 1710 2780 8500 2188 3480 3080 10550 2758 4200 Length on drum 4361 5631 51 7203 56 500 500 500 Current carrying capacity** inductance Nominal Underground Cables in duct Cable Trefail ation formation mm² 10 75 95 75 80 70 16 95 125 95 105 85 1.15 1.91 25 0.727 1.20 35 0.524 0.868 125 165 125 140 150 200 150 165 50 180 235 185 200 70 220 295 230 250 195 95 260 360 280 305 240 Cables in air Flat capacity Copper Alu Copper Ala Copper Ala Copper Ala Q/Km Q/Km mH/Km mH/Km F/Km Amp Amp Amp Amp Amp Amp 1.83 3.08 0.462 0.646 0.169 90 0.428 0.612 0.195 120 0.396 0.580 0.225 160 0.384 0.568 0.254 195 0.387 0.641 0.364 0.549 0.283 230 0.268 0.443 0.346 0.531 0.325 285 0.193 0.320 0.330 0.515 0.370 340 120 0.153 0.253 0.315 0.499 0.407 150 0.124 0.206 0.0991 0.164 0.301 0.485 0.487 485 0.0754 0.125 0.289 0.474 0.523 560 440 0.0601 0.100 0.288 0.472 0.548 630 500 0.0470 0.0778 0.274 0.459 0.598 720 570 0.0366 0.0605 0.270 0.454 0.631 800 640 990 790 855 0.0283 0.0469 0.263 0.448 0.711 910 740 1140 920 1000 800 0.0221 0.0367 0.252 0.437 0.832 1000 830 1300 1070 1165 1000 0.0176 0.0291 0.248 0.433 0.923 1090 920 1450 1220 1340 1090 At different operating T(C): R=R20°C (1+ a(TC-20)] 385 300 420 325 350 275 0.308 0.493 0.444 430 335 395 310 475 370 550 425 465 365 185 380 240 650 510 550 430 300 740 580 635 400 495 860 680 740 580 670 780 500 630 910 a: Temperature coefficient at 20°C=0.00393 for copper & 0.00403 for aluminium ** Laying conditions : -Underground: Temperature of the soil 20°C - Thermal resistivity 100 - In air : Ambient temperature 30°C *** Greater sizes are also available 500 500 500 105 125 155 E8-UEE-14 A 3 Phase, 6kV Electric Induction motor, rated at RanInt#(1800,2000) kVA is supplied through a 80m XLPE Cable, manufacturer Type M2NB, M2AB in Trefoil configuration. The details are attached. The power factor of this motor is 0.7 lagging. PART A (a) Write down the Rated kVA and kW of the Motor (b) Select a suitable cross section of the Cable (c) Determine its resistance and reactance and present this on a drawing (d) Determine the Voltage at the Supply End and Voltage drop in Voltage Magnitude and Efficiency in Per Unit (e) It is decided to reduce the cable voltage drop through a capacitor in series with the cable which will cancel out line reactance. Determine the value and KVAR rating of the capacitor and redo the voltage drop calculation. Comment on the result. PART B (a) S=P+jQ: Present this in a Power Triangle. (b) Discuss the benefits a techniques of power factor correction. (c) Show that the KVAR correction formula can be presented as: AKVAR= P(tan-tan (₂) (d) It is required to correct the power factor of the above motor from 0.7 to 0.9 power factor lagging. Calculate the value of capacitance of the capacitor and its KVAR. (e) Calculate the voltage drop and efficiency when both voltage drop and power factor correction are effected. 3.6/6 (7.2) KV-SINGLE CORE, XLPE INSULATED, PVC SHEATHED, SCREENED, UNARMOURED CABLES Type M2N, M2A - Conforming to IEC 60502-2 DIMENSIONAL CHARACTERISTICS Nominal Radial Thickness of Nominal Diameters Inner Outer cross section Indation Sheath Sheath Conductor Insulation Overall mm³ 10 16 25 35 mm 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 50 70 95 120 150 185 240 2.6 300 2.8 400 3.0 500 3.2 630 3.2 800 3.2 1000 3.2 Nominal cross section mm 14 1.4 1.5 7.15 13.15 19 8.3 1.6 10.0 16.0 1.7 11.8 17.8 1.7 13.3 19.3 1.8 14.8 20.8 1.8 16.55 22.55 29 1.9 18.73 24.93 31 2.0 21.3 27.9 35 2.1 24.1 31.3 37 2.2 27.3 41 34.9 2.3 31.0 39.0 45 2.5 37.1 45.0 2.6 41.6 49.6 ELECTRICAL CHARACTERISTICS 2.5 2.5 1.5 1.6 mm Kg/Km Kg/Km Kg/Km Kg/Km 3.82 9.82 15 90 310 28 245 4.83 10.83 16 142 385 43 285 6.02 12.02 17 224 500 68 350 311 610 95 400 421 755 128 465 608 985 185 Approximative net weight Aluminium cable Copper cable Conductor Cable Conductor Cable DC Resistance at Nominal 20°C 14.3 20 22 24 843 25 1065 500 500 560 500 685 500 1270 256 1530 324 790 500 1820 398 910 500 499 1050 500 2200 2740 638 1280 500 2646 3420 804 1570 500 3460 500 500 27 1307 1640 2098 4280 1051 1870 5300 1325 2280 6700 1710 2780 8500 2188 3480 3080 10550 2758 4200 Length on drum 4361 5631 51 7203 56 500 500 500 Current carrying capacity** inductance Nominal Underground Cables in duct Cable Trefail ation formation mm² 10 75 95 75 80 70 16 95 125 95 105 85 1.15 1.91 25 0.727 1.20 35 0.524 0.868 125 165 125 140 150 200 150 165 50 180 235 185 200 70 220 295 230 250 195 95 260 360 280 305 240 Cables in air Flat capacity Copper Alu Copper Ala Copper Ala Copper Ala Q/Km Q/Km mH/Km mH/Km F/Km Amp Amp Amp Amp Amp Amp 1.83 3.08 0.462 0.646 0.169 90 0.428 0.612 0.195 120 0.396 0.580 0.225 160 0.384 0.568 0.254 195 0.387 0.641 0.364 0.549 0.283 230 0.268 0.443 0.346 0.531 0.325 285 0.193 0.320 0.330 0.515 0.370 340 120 0.153 0.253 0.315 0.499 0.407 150 0.124 0.206 0.0991 0.164 0.301 0.485 0.487 485 0.0754 0.125 0.289 0.474 0.523 560 440 0.0601 0.100 0.288 0.472 0.548 630 500 0.0470 0.0778 0.274 0.459 0.598 720 570 0.0366 0.0605 0.270 0.454 0.631 800 640 990 790 855 0.0283 0.0469 0.263 0.448 0.711 910 740 1140 920 1000 800 0.0221 0.0367 0.252 0.437 0.832 1000 830 1300 1070 1165 1000 0.0176 0.0291 0.248 0.433 0.923 1090 920 1450 1220 1340 1090 At different operating T(C): R=R20°C (1+ a(TC-20)] 385 300 420 325 350 275 0.308 0.493 0.444 430 335 395 310 475 370 550 425 465 365 185 380 240 650 510 550 430 300 740 580 635 400 495 860 680 740 580 670 780 500 630 910 a: Temperature coefficient at 20°C=0.00393 for copper & 0.00403 for aluminium ** Laying conditions : -Underground: Temperature of the soil 20°C - Thermal resistivity 100 - In air : Ambient temperature 30°C *** Greater sizes are also available 500 500 500 105 125 155