A 2pole synchronous machine is connected to a 60 Hz electric

A 2-pole synchronous machine is connected to a 60 Hz electric system. The rotor and stator magnetic fields are shown in the figure, where B_r = 1 T, B_s - 0.25 T, = 12.78 degree, gamma = 75 degree, and the corresponding induced torque is 50 N m. What is the turning direction of the induced torque? Is this machine a generator or a motor? Mark the direction on the figure. What is the conversion power associated with this induced torque? If B_r = 1.5 T, B_s = 0.45 T, gamma = 60 degree, what is the new induced torque and the corresponding conversion power?

Solution

a) turning torque is in clockwise direction, machine works as motor

b) power= torque * speed

torque = k Bs*Br * Sin(delta)*cos(gamma)= 1.75

speed= 120*f/p =3600

power =62

c) new torque for gamma= 60

new torwue = 1.34