The amount of flux produced by the magnet indicates the strength of the magnet. The more the magnetizing force (MMF), the more is the flux produced. The more the opposition to the flux path (i.e., reluctance or magnetic resistance) less is the flux produced. This relationship is expressed as Flux = MMF/ Reluctance Reluctance is the opposition offered by the material in the flux path to the establishment of the flux. The reluctance in a magnetic circuit is similar to the resistance in an electric circuit. Reluctance is the inverse of permeance. MMF = Flux/Permeance
While estimating the overhead lines, the first and last pole is always earth connected and after every 3rd electrical pole, the fourth pole is earthed. Therefore, the approximate number of required ground set = 4
Given Power (P) = 20 kW = 20 × 103 W Voltage (V) = 200 V P = VI = I = P/V I = (20 × 103)/200 I = 100A For wave wound No. of Parallel Path = 2 Current in Each parallel Path for wave wound I = 100/2 = 50 A
The permeance of the magnetic circuit is defined as the reciprocal of the reluctance. Permeance = 1/Reluctance It is defined as the property of the magnetic circuit due to which it allows the flow of the magnetic flux through it. Permeance is analogous to conductance in an electric circuit.