A 10 hp, Y-connected, 60 Hz, 380 V, three-phase induction generator is used to drive a...

 

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A 10 hp, Y-connected, 60 Hz, 380 V, three-phase induction generator is used to drive a small micropower plant. The generator's load is 500 W for a 4 A line current at 1740 rpm. The rotor resistance is 4.56 Q at 75°C. The losses are equal to 28 W. A no-load test of the machine gave the following results: P=215 W, /= 3.0 A, and V = 380 V. Calculate the output power, the efficiency, and the power factor for the given load. If the generator was A-connected with the same data as mentioned earlier, what would be the difference in your calculations? 3.2 Explain the difference between rotor speed and rotor frequency. For s= -0.01 and a rotor speed of 1740 rpm, what is the rotor frequency for a 60 Hz induction generator? 3.3 Explain why the efficiency of an induction generator can be smaller when working as an asynchronous motor under certain conditions. 3.4 Calculate the efficiency of a 110 V, 60 Hz induction generator connected directly to the grid with the following parameters: Rm = 36.2 0; losses equal to 0.8% of the rated power; s = -0.03; R1 = 0.2 0; R2 = 0.15 0; X1 = 0.42 0; X2 = 0.43 0. 10 A 10 hp, Y-connected, 60 Hz, 380 V, three-phase induction generator is used to drive a small micropower plant. The generator's load is 500 W for a 4 A line current at 1740 rpm. The rotor resistance is 4.56 Q at 75°C. The losses are equal to 28 W. A no-load test of the machine gave the following results: P=215 W, /= 3.0 A, and V = 380 V. Calculate the output power, the efficiency, and the power factor for the given load. If the generator was A-connected with the same data as mentioned earlier, what would be the difference in your calculations? 3.2 Explain the difference between rotor speed and rotor frequency. For s= -0.01 and a rotor speed of 1740 rpm, what is the rotor frequency for a 60 Hz induction generator? 3.3 Explain why the efficiency of an induction generator can be smaller when working as an asynchronous motor under certain conditions. 3.4 Calculate the efficiency of a 110 V, 60 Hz induction generator connected directly to the grid with the following parameters: Rm = 36.2 0; losses equal to 0.8% of the rated power; s = -0.03; R1 = 0.2 0; R2 = 0.15 0; X1 = 0.42 0; X2 = 0.43 0. 10

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The rotor frequency is the electrical frequency fr of the current ... View the full answer