S Exercise 1: A 480V 60 Hz A-connected four-pole synchronous generator has the OCC shown in Fig. 1.This generator has a synchronous reactance of 0.1 2 and an armature resistance of 0.015 2. At full load, the machine supplies 1200A at 0.8 PF lagging. Under full-load conditions, the friction and windage losses are 40 kW, and the core losses are 30kW. Peal P a) What is the speed of rotation of this generator? b) How much field current must be supplied to the generator to make the terminal voltage 480V at no load? c) If the generator is now connected to a load and the load draws 1200A at 0.8 PF lagging, how much will be required to keep the terminal voltage equal to 480V ? d) How much power is the generator now supplying? How much power is supplied to the generator by the prime mover? What is this machine's efficiency? e) If the generator's load were suddenly disconnected from the line, what would happen to its terminal voltage ? f) Finally, suppose that the generator is connected to a load drawing 1200 A at 0.8 PF leading. How much field current would be required to keep VT at 480V. Open-circuit terminal voltage, V 600. 500 400. 300. 200. 100. 0. 0.0 1.0 20 3.0 4.0 4.55.0 Field current, A 6.0 7.0 8.0 9.0 10.0 36