Question $2$

$($a$)$ Draw labelled diagrams and state the voltage and current equations for

$($i$)$ Separately excited generator

$($ii$)$ Compound wound motor

$(8$ marks$)$

$(12$ marks$)$

$($b$)$ A four$-$pole d$.$c$.$ motor is connected to a $500$ V d$.$c$.$ supply and takes an armature current of $60$ A $.$ The resistance of the armature circuit is $0\mathrm{.}3.$ The armature is lap connected with $522$ conductors and the useful flux per pole is $0\mathrm{.}023$ Wb $.$ Calculate:

$($i$)$ the back e$.$m$.$f$.$ of the motor

$(3$ marks$)$

$($ii$)$ the speed of the motor

$(3$ marks$)$

$($iii$)$ the torque in kN m developed by the armature.

$(4$ marks$)$

$[$Total: $30$ marks$]$