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
A choke coil is simply a coil having a large inductance, but a small resistance. A device that can regulate the current in an A.C. circuit without much loss of energy is called as ‘choke coil’.
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
Lap Winding:-In a lap winding the number of parallel paths (a) is always equal to the number of poles (p) and also to the number of brushes. In the given question number of poles is 4 hence the number of brushes will be 4. Wave Winding:- In wave windings, the number of parallel paths (a) is always two and there may be two or more brush positions.