Publem #5: The eddy current loss of a dc machine is 300 W when the flux per pole is 30 mWb and the machine is driven at 1000 rpm. How much is the loss if the field is adjusted to produce 50 mWb per pole while the speed is reduced to 900 rpm?

A ferromagnetic core is shown in Figure PI-2. The depth of the core is 5 cm. The other dimensions of the core are as shown in the figure. Find the value of the current that will produce a flux of 0.005 Wb. With this current, what is the flux density at the top of the core? What is the flux density at the right side of the core? Assume that the relative permeability of the core is 1000. -10 cm- - 20 cm- 15 cm 400 turns 15 cm 15 cm Core depth 5 cm

Q3. A 4-pole machine has an armature with 90 slots and 8 conductors per slot, the flux per pole is 0.05 Wb and runs at 1,200 rpm. Determine induced emf if winding is (i) lap connected and (ii) wave connected. (Ans. 720 V, 1440 V) hee 400 ful fluy of 0 05 W/h Whet u