Question

What is the formula for dispersion coefficient?

(a) dispersion coefficient = 0.838 * 10^6 * 3.14 / air gap length * effective specific permeance / pole pitch * (window space factor)^2 * number of slots per pole per phase

(b) dispersion coefficient = 0.838 * 10^6 * 3.14 * air gap length / effective specific permeance / pole pitch * (window space factor)^2 * number of slots per pole per phase

(c) dispersion coefficient = 0.838 * 10^6 * 3.14 * air gap length * effective specific permeance * pole pitch * (window space factor)^2 * number of slots per pole per phase

(d) dispersion coefficient = 0.838 * 10^6 * 3.14 * air gap length * effective specific permeance / pole pitch * (window space factor)^2 * number of slots per pole per phase

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Answer 1

Correct choice is (d) dispersion coefficient = 0.838 * 10^6 * 3.14 * air gap length * effective specific permeance / pole pitch * (window space factor)^2 * number of slots per pole per phase

Best explanation: For the calculation of dispersion coefficient, first the air gap length, effective specific permeance is calculated. Next the pole pitch, window space factor and the number of slots per pole per phase.