Question

In: Electrical Engineering

A three phase, 60 Hz, 480 V, Y-connected, two-pole synchronous generator has a synchronous reactance of...

A three phase, 60 Hz, 480 V, Y-connected, two-pole synchronous generator has a synchronous reactance of 0.95 Ω per phase. Its armature resistance is negligible. Its combined friction and windage losses are 1.3 kW and its core losses are 0.95 kW. The field current is constant at no-load. Its full load armature current is 55 A at 0.9PF lagging. Assume phase voltage is a reference. Determine following:

a) Its terminal voltage when it is loaded with the rated current at a power factor of 0.9 lagging

b) Its terminal voltage when it is loaded with the rated current at a power factor of 0.9 leading

Hence,

Answer for a (0.9 lagging) should equal VT= 433.59 V

Answer for b (0.9 leading) should equal VT= 512.486 V

Solutions

Expert Solution

Hence I calculated both 0.9 leading and lagging pf terminal voltages


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