Скачать или смотреть V31 SIMPLEX DOUBLE LAYER PROGRESSIVE LAP WINDING WITH EQUALIZER RINGS FOR DC MACHINES

DRAW THE DEVELOPED WINDING DIAGRAM OF A DC MACHINE FOR 16 SLOTS, 4 POLES; DOUBLE LAYER SIMPLEX PROGRESSIVE LAP WINDING. SHOW THE POLES, DIRECTION OF EMF INDUCED IN THE CONDUCTORS, POSITION AND POLARITY OF BRUSHES. ALSO SHOW THE EQUALIZER RING CONNECTIONS.

SOLUTION:
NO. OF POLES (P) = 4
NO. OF SLOTS (S) = 16
NO. OF CONDUCTORS (Z) = 32 (DOUBLE LAYER)
POLE PITCH (YP) = Z/P = 32/4 = 8

YB + YF= 2 x POLE PITCH; YB + YF = 2 x 8;
YB + YF = 16 ------------------ (1)
YB - YF = 2m; YB - YF = 2 (m = 1 FOR SIMPLEX WINDING)
YB - YF = 2 -------------------- (2)
SOLVE (1) & (2)
YB = 9 & YF = 7
FOR SIMPLEX LAP WINDING YB & YF SHOULD BE ODD AND DIFFER BY 2. BY SATISFYING THIS CONDITION WE CAN PROCED FOR WINDING TABLE BY CONSIDERING YB = 9 & YF = 7 WHICH INDICATES THE FRONT AND BACK CONNECTIONS OF CONDUCTORS.

ABOUT EQUALIZER RINGS: THE EMF INDUCED IN VARIOUS PARALLEL PATHS MAY NOT BE EQUAL DUE TO SOME REASONS LIKE DIFFRENCE IN THE VALUES OF RELUCTANCE OF CORRESPONDING IRON PARTS OF MAGNETIC CIRCUIT, LENGTH OF AIR GAP & STRENGTH MAY NOT BE SAME FOR ALL THE POLES. DUE TO THIS UNEQUAL EMF A LARGE CIRCULATING CURRENT MAY PRODUECD AND IT LEADS TO I^2R LOSSES IN WINDING AND ALSO COMMUTATION DIFFICULTIES MAY ACCURE. IN ORDER TO GET RID OF THIS EQUALIZER RINGS ARE USED. (EQUALIZER RINGS ARE NOT USED IN WAVE WINDINGS)

NUMBER OF EQUALIZER RINGS = Z/(2 x P) = 32/(2x4) = 4
NUMBER OF TAPPINGS TO EACH RING = P/2 = 4/2 = 2
DISTANCE BETWEEN ADJACENT TAPPINGS = (TOTAL No OF COILS / TOTAL No OF TAPPINGS)
= (32/2) / (4 x 2) = 2 COILS