Question 5 (Svnchronous machines) a. A synchronous generator connected to an infinite grid has its frequency and terminal b. A six-pole, Y-connected three-phase synchronous machine rated 208 V (line-...
A 3-phase, 7 kVA, 400 V, 2-pole, star-connected synchronous machine has negligible armature resistance and Xs-60/phase at rated terminal voltage The machine first runs as a generator in parallel with 3-phase, 400 V, 50 Hz power supply 111 Determine the generated voltage and torque angle of the machine operating as a generator, delivering rated kVA at 0 9 pf lagging Draw and label the corresponding phasor diagram for this condition 1 12 If the field excitation is increased by 18%...
A three-phase, delta-connected, two-pole, synchronous generator is connected to a 60 Hz, 13.5 kV (line-to-line), system. The generator is delivering its rated output power, under which conditions pfload = 0.8 lagging and |SI = 20 MVA. The generator per-phase model parameters at rated load are. RA = 0.5 2 Xss = 522 9. What is the generator's line-to-line voltage regulation? Is the voltage regulation positive or negative? 10. If the field current is held at the rated load value, but...
Problem #2: A three-phase synchronous generator is rated 16 kV and 200 MVA, has negligible losses and has reactance of 1.65 pu. The generator is operated on an infinite bus of 15 kV voltage and delivers 100 MVA at 0.8 Power Factor, lagging. a)Determine the internal voltage (E_i), the power angle (5), and the line current of the machine. b)If the field current of the machine is reduced by 10%, while the mechanical power input to the machine is maintained...
Question 4 (10 marks) A) A 10-kVA, 415-V, three phase, Y -connected synchronous generator has a winding resistance of 0.3 Q and a synchronous reactance of 0.6 on a per phase basis. Determine its voltage regulation at full load when the power factor is (a) 75% lagging and (b) 75% leading. B) (10 marks) A 220-V, Y-connected, three-phase, synchronous motor has a synchronous reactance of 4 O/phase and negligible armature winding resistance. At a certain load the motor takes 7.5...
A 480 V, 60 Hz, 470 kVA, 0.85 PF lagging, 2-pole, Y-connected synchronous generator has a synchronous reactance of XS=0.016 Ω and an armature resistance of RA=0.016 Ω. At rated conditions the core losses are 7 kW. Friction losses and field winding losses are 8 kW. Suppose the machine is connected to an infinite bus (hence the terminal voltage is fixed) and it is running at the rated conditions. a) What is the rotor speed in rpm? b) Calculate the...
b) A 1MW, 3300 V, 50 Hz, wye-connected, 3-ф, twenty four-pole, synchronous motor has a synchronous reactance of 3.24 2 per phase. Assume armature resistance is negligible. This machine is connected to an infinite bus-bars at 3300 V. Its field excitation is adjusted to provide P.F-1 at rated load Calculate: 0 the internal generated voltage EA and armature current la at rated conditions (S marks) ii) the maximum power and torqu e that the motor can deliver with its Ir...
3. A 480 V, 60 Hz, 470 kVA, 0.85 PF lagging, 2-pole, Y-connected synchronous generator has a synchronous reactance of Xs=0.0162 and an armature resistance of RA=0.0.1622. At rated conditions the core losses are 7 kW. Friction losses and field winding losses are 8 kW. Suppose the machine is connected to an infinite bus (hence the terminal voltage is fixed) and it is running at the rated conditions. a) What is the rotor speed in rpm? b) Calculate the phase...
A 75 MVA, 25 Kv, three-phase, 60 Hz synchronous generator has a synchronous reactance of X= 9 Ω per phase and a negligible resistance. The generator is delivrimg rated power at a 0.8 power factor lagging at the rated terminal voltage to an infinitie bus, as shown in the following figure 1. Figure 1.The synchronous generator connected to infinite bus in single phase. 1) The excitation voltage is E = 26.87 KV, The generator delivring 60 MW. Compute the powe...
Consider a 3-phase, 4 pole, 60Hz, 450 V synchronous generator rated to supply 1687.5 kVA to a ship distribution system requiring a 0.8 lagging power factor. (a) If this machine was operating at rated conditions, what would the real (P) and reactive (Q) power and the current being supplied? (b) If the generator has an efficiency ( η ) of 95%, what torque does the prime mover provide? (c) What is the speed of the rotor (rpm)?
S. A three-phase, 4-pole, Y-connected synchronous generator is rated 575V, 200k VA, 60Hz. The generator's synchronous reactance is X-0.Q. Losses are negligible. The generator is comnected to an ideal 575V three- phase 60 Hz bus. Use V, for phase a-to-neutral as the reference angle (a) The generator's input power is 150kW. The generator's field current is adjusted to 10A which caases the generator to operate at unity power factor. What is the generator's phase-a armature current Ia (magnitude and phase)?...