A 3-phase, Y-connected synchronous generator with a synchronous reactance of 4 Ohms/phase is connected to an infinite bus whose voltage is 6.6kV. The maximum output of the machine is 16MW. Compute the internally generated voltage Eg at the maximum possible power output condition. Ans-9.7kV
The power output is gradually reduced to 10MW without changing the field current. Find the new current, power factor, and power angle delta. Compute the reactive power generated by the machine. Ans-delta=38.7 deg; 886 at -9.1 deg Amps; 1.58 MVAR
If the machine is required to generate no reactive power (PF=1) while supplying the same real power by changing the field current, find the new internally generated voltage and corresponding power angle delta. Ans-8.96 kV at 42.6 deg.
If the machine is now required to run a s synchronous motor, calculate the power output, reactive power, current and power factor when the power angle is 30 degrees. Ans- 668A; power angle 14.5 deg; 7.39 MW; 1.91 MVAR