Challenging Engineering Problems with Detailed Answers

Describe the design technique used to implement a circuit that requires precise properties when the deviation of the absolute value of the resistance or capacitor value is about 20% in designing an integrated circuit design.
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. You are given two areas connected by a tie-line with the following characteristics Area 1 R=0.005 pu D=0.6 pu Area 2 R = 0.01 pu D=1.0 pu Base MVA =500 Base MVA = 500 A load change of 150 MW occurs in Area 2. What is the new steady-state frequency and what is the change in tie-line flow? Assume both areas were at nominal frequency (60 Hz) to begin 620 Dal
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design a two stage amplifier that produces the following output:V0 = 3V1 + 2V2 + 4V3a. draw the block diagram for this systemb. implement the block diagram for this circuit using op amps. ensure that all resistors drawn have values.c. if V1= 1V, V2= 2V, V3= 2V, what should be the minimum Vcc of both amplifiers so that neither stage is saturated?
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We want to design a modulo-3 counter by designing appropriate logic to apply to the To and T inputs of two T flip flops as shown below: Input logic 0 To Qo Input logic 11 T Q Ck Ck Q M The counter should follow the count sequence Q1200001 10 00 01 10, etc... If at any point Q20 = 11 (this could occur at turn-on of the circuit, as the initial state of the flip-flop at tum on is random and unpredictable) then the system should transition on the next clock cycle to Q1 20 01. = Extract the required logic for the input to To To - Q1 To = 20 O To=21+20 To = 21 20 Extract the required logic for the input to T: T = 21 OT=20 O T1 = 21 +20 OT1-21-20
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) Figure 1 shows the internal circuitry for a charger prototype. You, the development engineer, are required to do an electrical analysis of the circuit by hand to assess the operation of the charger on different loads. The two output terminals of this linear device are across the resistor, RL. You decide to reduce the complex circuit to an equivalent circuit for easier analysis. i) Find the Thevenin equivalent circuit for the network shown in Figure 1, looking into the circuit from the load terminals AB. (9 marks) R1 R2 40 +++ 20 V R460 10A R330 Figure 1 ii) Determine the maximum power that can be transferred to the load from the circuit.
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(26 pts) Let v(t) = 120 sinc(120t) - 80 sinc(80t). (a) (6 pts) Find V(f). Considering v as a passband signal, what is its 100% energy containment bandwidth? (b) (8 pts) Find (t), the Hilbert transform of v. (c) (4 pts) Let u(t) = v(t) cos(250t). Sketch U(f). (d) (8 pts) Find env(t), the complex envelope of u(t).
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A microwave oven (ratings shown in Figure 2) is being supplied with a single phase 120 VAC, 60 Hz source. SAMSUNG HOUSEHOLD MICROWAVE OVEN 416 MAETANDONG, SUWON, KOREA MODEL NO. SERIAL NO. 120Vac 60Hz LISTED MW850WA 71NN800010 Kw 1.5 MICROWAVE UL MANUFACTURED: NOVEMBER-2000 FCC ID : A3LMW850 MADE IN KOREA SEC THIS PRODUCT COMPLIES WITH OHHS RULES 21 CFR SUBCHAPTER J. Figure 2 When operating at rated conditions, a supply current of 14.7A was measured. Given that the oven is an inductive load, do the following: i) Calculate the power factor of the microwave oven. ii) Find the reactive power supplied by the source and draw the power triangle showing all power components. iii) Determine the type and value of component required to be placed in parallel with the source to improve the power factor to 0.9 leading. 725F
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(18) 3. Use superposition to find vx. VJ. 51 1002 +x- 3A ( 15V 452
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Periodic signals with wo = 2000 is described by the following, (not realistically): Vin(t) = 4 cos (10000 t-5) i. ii. Vin(t) 10 Vo(t) 10uF It is input into this above circuit. State the Alternative Fourier Series co-efficient(s) (An 20) of the output. State the Alternative Fourier Series of the output.
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A microwave oven (ratings shown in Figure 2) is being supplied with a single phase 120 VAC, 60 Hz source. SAMSUNG HOUSEHOLD MICROWAVE OVEN 416 MAETANDONG, SUWON, KOREA MODEL NO. SERIAL NO. 120Vac 60Hz LISTED MW850WA 71NN800010 1.5 Kw MICROWAVE (UL) MANUFACTURED: NOVEMBER-2000 FCC ID: A3LMW850 MADE IN KOREA SEC THIS PRODUCT COMPLIES WITH OHHS RULES 21 CFR SUBCHAPTER J. Figure 2 When operating at rated conditions, a supply current of 14.7A was measured. Given that the oven is an inductive load, do the following: i) Calculate the power factor of the microwave oven. (2 marks) ii) Find the reactive power supplied by the source and draw the power triangle showing all power components. (5 marks) iii) Determine the type and value of component required to be placed in parallel with the source to improve the power factor to 0.9 leading.
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A 3-phase generator with reactance of 15% on its rating of 22.5 MVA at 16 kV (line), feeds into a 16/132 kV step-up transformer with reactance of 10% on its rating of 25 MVA. Calculate the short-circuit current in kA and also in MVA for a 3-phase fault on (a) the generator terminals and (b) the 132kV terminals for the step-up transformer.
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An exact model of 40 kVA single phase transformer is shown as below. eeeee 000 Equivalent circuit of transformer Load Based on a load condition, some given or calculated parameters are: primary resistance = 0.3 ohm; primary reactance = 0.092 ohm ;Equivalent core loss resistance = 1500 ohm; Magnetizing reactance = 256 ohm; Secondary resistance = 0.075 ohm; Secondary reactance = 2.5 ohm; Primary current = 4.5 A; Secondary current = 54 A; primary induced voltage = 240 V, Calculate the total power loss in Watt of the transformer
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: + A VAB (t) + VBc(t) - Rsyst Xsyst + Rsyst VCA (1) iAL (t) Xsyst i Aph (t) Rsyst Xsyst Mmm a N iaph (t) Vab (t) D D D D D, C7 Rload + Vload (t) power system AY transformer rectifier filter load FIGURE P1.1 Connection of a delta/wye three-phase transformer with a diode rectifier, filter, and load.
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i can't find transfomer in easyeda. can someone show me how to find it. thank you in advance
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A DFIG supplies a step-up transformer of j0.1 pu impedance & thence a transmission system of impedance j0.12 p.u. Assume beyond this is an infinite bus. The DFIG supplies rated power at unity PF into the infinite bus. The DFIG has an equivalent reactance Xeq of 0.8 per unit. All impedances on 100 MVA power base, 3-phase. Calculate direct and quadrature current components Ip and Iq, and internal voltage Eq.
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As an engineer for a private contracting company, you are required to test some dry-type transformers to ensure they are functional. The nameplates indicate that all the transformers are 1.2 kVA, 120/480 V single phase dry type. (a) With the aid of a suitable diagram, outline the tests you would conduct to determine the equivalent circuit parameters of the single-phase transformers. (6 marks) (b) The No-Load and Short Circuit tests were conducted on a transformer and the following results were obtained. No Load Test: Input Voltage = 120 V, Input Power-60 W, Input Current = 0.8 A Short Circuit Test (high voltage side short circuited): Input Voltage = 10 V, Input Power-30 W, Input Current = 6.0 A Calculate R. XR and X (6 marks) eq (c) You are expected to predict the transformers' performance under loading conditions for a particular installation. According to the load detail, each transformer will be loaded by 80% of its rated value at 0.8 power factor lag. If the input voltage on the high voltage side is maintained at 480 V, calculate: i) The output voltage on the secondary side (4 marks) ii) The regulation at this load (2 marks) iii) The efficiency at this load (4 marks) (d) The company electrician wants to utilize three of these single-phase dry type transformers for a three-phase commercial installation. Sketch how these transformers would be connected to achieve a delta-wye three phase transformer.
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per pole QUESTION SEVEN A 3HP, 3-phase induction motor with full load efficiency and power factor of 0.83 and 0.8 respectively has a short-circuit current of 3.5 times the full current. Estimate the line current at the instant of starting the motor from a 500% supply by means of star-delta switch. Ignore the magnetising current.
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A system with input r(t) and output y(t) is described by y" (t) + y(y) = x(t) This system is 1) over-damped 2) under-damped 3) critically damped 4) undamped
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Figure 1 shows the internal circuitry for a charger prototype. You, the development engineer, are required to do an electrical analysis of the circuit by hand to assess the operation of the charger on different loads. The two output terminals of this linear device are across the resistor, RL. You decide to reduce the complex circuit to an equivalent circuit for easier analysis.i) Find the Thevenin equivalent circuit for the network shown in Figure 1, looking into the circuit from the load terminals AB.20 VR1www40R4 6010AFigure 1R230R3 < 30ABRLii) Determine the maximum power that can be transferred to the load from the circuit.b) A microwave oven (ratings shown in Figure 2) is being supplied with a single phase 120 VAC, 60 Hz source.SAMSUNGHOUSEHOLD MICROWAVE OVEN416 MAETANDONG, SUWON, KOREAMODEL NO.SERIAL NO.120Vac60HzLISTEDMW850WA71NN800010Kw1When operating at rated conditions, a supply current of 14.7A was measured. Given that the oven is an inductive load, do the following:i) Calculate the power factor of the microwave oven.ii) Find the reactive power supplied by the source and draw the power triangle showing all power components.iii) Determine the type and value of component required to be placed in parallel with the source to improve the power factor to 0.9 leading.
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Sketch the construction an op-amp circuit with an input impedance of 1 k2 which performs the following calculation VOUT = -A(VIN) where A = 10 and VIN= +0.1 V w.r.t ground. Justify your choice of components and indicate component values in your sketch. Note that you should treat the op-amp as an ideal device).
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x(t) h(t) h (t) y(t) h (t) 2) [20 pts] Find the equivalent transfer function H(s) = Y(s)/X(s) and impulse response h(t) h(t) = 5u(t-2) h(t) = e-tu(t) h(t) = eu(t)
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A stainless steel manufacturing factory has a maximum load of 1,500kVA at 0.7 power factor lagging. The factory is billed with two-part tariff with below conditions: Maximum demand charge = $75/kVA/annum Energy charge = $0.15/kWh Capacitor bank charge = $150/kVAr Capacitor bank's interest and depreciation per annum = 10% The factory works 5040 hours a year. Determine: a) the most economical power factor of the factory; b) the annual maximum demand charge, annual energy charge and annual electricity charge when the factory is operating at the most economical power factor; c) the annual cost saving;
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A three phase generated rated 440V, 20kVA is connected through a cable with impedance of 4+j15 to two loads as shown in the figure below: A three phase, Y connected motor load rated 440V, 8kVA, p.f. of 0.9 lagging A three phase, Delta connected synchronous motor load rated 440V, 6kVA, p.f. of 0.85 leading. If the motor load voltage is to be 440V, find the required generator voltage
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Three loads, each of resistance 30 Q are connected in star to a 415 V, 3-phase supply. Determine i. ii. iii. The System Phase Voltage The Phase Current And The Line Current. b. A 415 V, three-phase, 50 Hz, 4 pole, star-connected induction motor runs at 24 rev/s on full load. The rotor resistance And reactance per phase are 0.35 2 and 3.5 2 respectively, and the effective rotor-stator turns ratio is 0.85:1. Calculate i. ii. ii. The Synchronous Speed The Slip, The Full Load Torque
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