10. Two identical 5 kW, 220 V, 24 A dc shunt machines are to be used as the gene- rator and motor in a Ward-Leonard system. The armature resistance of each machine is 0.5 ohm and the magnetization curve for each machine at 1500 rpm is given below: Field current, A Induced emf, V 0.2 80 0.4 0.6 0.8 1.0 1.2 1.4 160 210 228 237 243 247 The generator is driven at a constant speed of 1500 rpm. (a) Determine the maximum and minimum values of the generator field current required to give the motor a speed range of 100 rpm to 1500 rpm at full load armature current of 24 A, with the motor field current held constant at 0.6 A. (b) Determine the maximum motor speed obtainable at full load armature current if the motor field current is reduced to 0.10 A and generator field current is not allowed to exceed 1.2.A.

Dc generator

The total conductor of the direct current generator shown in the figure is 1440. The length of the armature is 30cm, the magnetic flux of a pole is 0.8 Tesla and the armature rotates at a speed of 4 m / s. Find the value of the voltage generated by the armature according to the position in the figure.

The armature of a 4 -polelap wound shunt generator has 400 conductors.The flux per pole is 0.05 Wb.The armature and field resistance are 0.05Qand 500. Find the speed of the machine when supplying 450 A at a terminal voltage of 250 V.