B-State the steps to obtain zero power factor characteristic of synchronous generator? A- i- ii- iii- For synchronous machines :- Define with plot the V-curves of synchronous motor? State the equation of power developed by three phase salient pole synchronous generator and draw the power angle characteristic for it? Discuss the hunting of synchronous motor?

A three-phase, 1 MVA, 2.3 kV, 60 Hz, star-connected, salient pole synchronous generator has the d- and q-axis synchronous reactances are 1.1 and 0.8 Q respectively. Its armature has a resistance of 0.15 §. The machine is operating at full load at a power factor of 0.8 lagging. Determine the excitation voltage Ę and draw the generator phasor diagram using actual values.

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1-transfer function of DC Series motors. 2-block diagram of DC Series motors.

A)-An 8-pole lap wound d.c shunt generator has 120 slots with 4 conductors per slot. If each conductor can carry 250 A and flux per pole is 50 mWb. Find the speed so that it gives 240 V on open circuit. If the terminal voltage of the generator drop to 220 on full load, find the armature resistance.

With the aid of diagrams describe the basic topology of a wound field 3 phase synchronous generator and outline the relationship between the excitation voltage and rotor current. Q2 (a) (b) Outline with the aid of a suitable diagram the necessary power conversion stages required to interface a small permanent magnet (PM) generator to a stand alone DC system. A star connected 3 phase wound field synchronous generator with a synchronous reactance of 20 N is connected to a 6.6 kV (phase voltage) grid and supplies 1.5 MW at 0.95 lagging power factor at its terminals. Calculate the phase current and resultant voltage across the synchronous reactance (Vxs), and from a scaled phasor diagram graphically determine the required excitation voltage (Eph) and load angle (8). (c) The load is now increased to 3 MW with the Excitation Voltage kept constant. Using the phasor diagram drawn in part (c) graphically determine the resultant phase current, power factor and load angle. (d)

A3 phase, 1500 rpm, 2200 V, star connected synchronous motor having per phase impedance 0.4 + J9 ohms. On some excitation armature induces 2900 V. Find the maximum torque developed by the motor before the motor is separated from synchronism.

A 480 V, 60 Hz ,Delta Connected, Four Poles Synchronous Generator has A Direct Axis Reactance of 0.1 Ohm, and Quadrature Axis Reactance of 0.075 Ohm .Its Armature Resistance May be Neglected. At Full Load, This Generator Supplied 1200 A , at A Power Factor Of 0.8 Lagging. 1-Find The Internal Generated Voltage (E), of This Generator at Full that it has A Cylindrical Rotor of Reactance Xd ( Xd =Xs). Load . Assuming 2- Find the Internal Generated Voltage E, of this Generator at Full Load. Assuming It has Salient Pole Rotor.

Two D.C shunt generators running in parallel supply s total load current of 125A. The shunt field and armature resistances of each machine are 50 ohms and 0.4 ohms respectively. The e.m.f.s. of the two generators at no load are 260 V and 250 V respectively. Determine the following a. Current supplied by each generator: and b.The bus bar voltage

answer atleast five parts