A long shunt generator delivers 50 A at 500 V at full load. The shunt field, armature and series field resistances are 400 Ω, 0.2 Ω and 0.08 Ω respectively. Iron loss is 1200 W and friction and windage losses total 800 W. Then find the total efficiency of the generator.

A 50kW, 500V short shunt generator has an armature resistance, series field resistance and shunt field resistances are 0.05 ohms, 0.06 ohms and 253 ohms respectively. What is the power generated?

AC Machinery Fundamentals A three-phase delta-connected six-pole winding is installed in 36 slots on a stator. There are 150 turns of wire in each slot of the windings. All coils in each phase are connected in series. The flux per pole in the machine is 0.060 Wb, and the speed of rotation of the magnetic field is 1000 r/min. What are the resulting phase and terminal voltages?

Figure 1 shows an electric generator with 3 rotor windings as marked by a-1, b-2 and c-3. A permanent magnet is placed in the middle of the rotor with the rotational direction. The 3 rotor windings are connected through line to the three identical load resistors R₁, R₂ and R3 in Wye connection. The resulting currents in each line are la, lb and Ic. Design the generator-line-load connections, and propose the methodologies to construct 3-phase 3-wire connection. Use a diagram to justify your answers. D (0 N $1 Figure 1

A 50 Hz CT has 20 primary turns and 60 secondary turns, on a core of cross section 8 cm2. The secondary current is 5 amp. The impedance of the burden and the secondary winding are together equal to 0.7 + j 0.4 ohm. The excitation current required in the primary current to produce the working flux with the secondary open circuit is 0.6 angle 45 amp. Calculate the flux density in the core and the ratio and phase errors.

4. An a-c generator has six poles and operates at 1,200 rpm. (a) What frequency does it generate? (b) At what speed must the generator operate to develop 25 cycles? 50 cycles? (c) How many poles are there in a generator that operates at a speed of 240 rpm and develops a frequency of 60 cycles? () -I Cycle- (0) Two poles - one cycle per revolution. N N -2 Cycles (A Four poles-two cycles per revolution. AN LS ANA LEJ ANA LSJ -3 Cycles (c) Six poles -three cycles per revolution. Sketch illustrating the relation between the number of poles and the generated a-c frequency in cycles per revolution. Current Current Current

5-5.When one coil of a magnetically coupled pair has a current 5.0 A the resulting fluxes ?11and ?12 are 0.2mWb and 0.4mWb, respectively. If the turns are N1= 500 and N2=1500, find L1, L2, M, and the coefficient of coupling k

A four pole machines generates 250V when operated at 1500 rpm. If the flux per pole is 1.85 x 106 maxwell, the number of armature slots is 45 and the armature winding has two parallel paths. If the speed of the generator is reduced to 1350 rpm, what would be the generated voltage. To what value of flux per pole should the excitation be adjusted if the generated voltage is to remain the same at 250V

A generator with simplex-lap winding has the following specifications: P = 4 poles turn coil s 1 (CONTINUATION AT commutator segments = 25 500 rpm speed conductor = 2 -> number of slots slot flux per pole = 1.8 x 106 Maxwell

A three-phase Δ-connected six-pole winding is installed in 36 slots on a stator. There are 150 turns of wire in each slot of the windings. All coils in each phase are connected in series. The flux per pole in the machine is 0.060 Wb, and the speed of rotation of the magnetic field is 1000 r/min. (a) What is the frequency of the voltage produced in this winding? (b) What are the resulting phase and terminal voltages of this stator?