Reluctance, Flux

(See attached file for full problem description) --- The magnetic circuit shown in figure below is built up of solid iron cross section, 1 x 1 cm2. Each air gap is 1 mm wide. For this type of air gap, the effective cross-section of air may be taken as 1.2 x that of iron path to allow for fringing. Two different grades of iron are used. When a coil having 2000 turns is wound on part B, and a current of 0.5 A is applied to it, the relative permeability of part A is measured as 500 and of part B as 1000. Calculate: a) Reluctance of part A, b) Reluctance of part B, c) Total reluctance of the air gap, d) The mmf, e) Total flux & f) Flux density in the iron pats.

Hysteresis and Eddy-Current Losses

Consider the core shown in the figure below. The mean length of magnetic path is 40cm and the effective area of cross section of the core is 9cm2. The number of turns in the exciting coil is 400. When a sinusoidal voltage of 200V (RMS) at frequency of 50Hz is applied to the exciting coil, the hysteresis loss is found to be 36 W and the eddy current loss 18 W. The Steinmetz exponent for the magnetic material may be assumed to remain constant at a value of 1.6. Determine the hysteresis and eddy-current losses when a triangular voltage v(t) shown in the figure below is applied to the exciting coil. Assume that the voltage drop in the resistance of the exciting coil is negligible. (see diagr... click for more