Kw=Kp∗Kd=cot15°/3√2 7. For eliminating nth harmonic from the EMF generated in the phase of a 3-phase alternator, the chording angle should be
A. n∗full pitch
B. (1/n)∗full pitch
C. (2/n)∗full pitch
D. (3/n)∗full pitch
Answer:A
Kw=Kp∗Kd=cot15°/3√2 7. For eliminating nth harmonic from the EMF generated in the phase of a 3-phase alternator, the chording angle should be
A. n∗full pitch B. (1/n)∗full pitch C. (2/n)∗full pitch D. (3/n)∗full pitch
Explanation: kpn=cosnε/2=0 ⇒ nε/2=90° ⇒ ε=180°/n= full pitch/n.