The magnetic circuit of a 4-pole dc machine with an active length of 56 mm is shown in Figure 1….

The magnetic circuit of a 4-pole dc machine with an active length of 56 mm is shown in Figure 1. Determine the mmf per pole needed to establish a flux density of 1.0 T in the air-gap. Assume that the effective arc of the air-gap is the same as the width of the pole. Use the B-H relationship as given byB = 2.5(1 – e-^-H/1000). Using the equivalent reluctance circuit, verify the mmf requirements per pole.