Developed diagram of simplex progressive 2 layer lap winding, Electrical Engineering

Q. Draw the developed diagram of a simplex progressive 2 layer lap winding for a 4 pole generator with 12 coils clearly indicating the position of brushes.


Sol.  No. of commutator segments = no. of coils, C = 12, Twelve coils have 24 coil - sides. For two coil - sides per slots,


                Total no. of slots = 24/2 = 12


                Back pitch,      yb = 2C/P ± K = 24/4 ± 1 = 7 or 5


                For progressive lap winding,


                    Yw = yb - yf = +2


                     yf = 5 for yb = 7

            or yf = 3 for yb = 5


        It is desirable that yb + yf/2 should be as nearly equal to pole pitch as it possible. In view of this, yb = 7 and yf = 5 should be chosen for this commutator machine, because 7 +5/2 = pole pitch in terms of coil - sides (= 24/4 coil - sides per pole).


                     For probressive simplex lap winding, commutator pitch,


                             Yc = +1


For drawing the winding diagram in radial form, 12 commutator or segments, 12 slots and 24 coils sides are first drawn. Now segment 1 is connected to top coil - sides 1 and then to bottam coil - sides 8 (1 + yb = 1 +7). Note that the coil - sides 1 and segment 1 are so numbered tha the coils resemble a lap coil. Since yC = 1, the coil - sides 8 is connected to segment 2 (1 + yC = 1 +1).Bottom couil - side is now connected to top coil - sides 3 (8-yf = 8-5), then to bottom coil - sides 10 (3 +7), then to top coil - side 5 (10-5), then to bottom is helpful in drawing this winding diagram.


        + yb                    -yf                 +yb           -yf             +yb


         (1 - → 8) - →      (3 - →   10)  - →       (5 - →   12)- →


     (7  → 14) → (9 → 16) →         (11 → 18) →             (13 → 20)   →


    (15 → 22) → (17 → 24)(19 → 26 or 26-24, i.e. 2) → (26 → yf or 21 → 21+yb, i.e. 4) → (28 - yf i.e. 23 → 6) → 1


                In the winding table (1→8) means that the top coil - side 1 is, connected to bottom coil - side 8 to form one coil. Same is true for all other coils. Note that winding table does not contain any no, greater than 24 ( = total no. of coil - sides). Each coil - sides is used only once in the winding table and the winding closes on itself (starting from 1 and ending on 1)


        In this machine with 12 slots and 4 pole, 3 slots are assumed to be under the effect of each pole. For example, 3 slots with coil - side 7 to 12 under the adjacent S pole and so on. Direction of e.m.fs. and current in the coil - sides under N pole are indicated by, cross and those under S pole denoted by dot. Now the directions of currents can be marked by noting that current flows from segments to cross - marked coil - sides and to the segments from dot - marked coil - sides.


                                               A careful examination of winding reveals that current leave at the commutator segments, 1, 7 and the current enter at the commutator segments 4, 10. Thus four brushes A, B, C, D can be placed in contact with segments 1, 4, 7, 10 respectively. Brushes A and C have the same polarity. These can, therefore, be joined together, similarly brushes C and D can be joined. Armature power can be handled at the terminals marked E, F. If E and F are given are negative and positive polarities respectively; the machine works as motor with the direction of rotation anti - clockwise.


           From brushes A, one parallel path is through coils a, b, c to brush B and the second parallel path is through coils l, k, j to brush D. From brush C, one parallel path is through coils f, e, d to brush B and the second parallel path through coils g, h, I, o brush D. These parallel path at any instant. There are thus four parallel paths for a 4 - pole machine - in general, for a simplex lap winding, no. of parallel paths A is equal to the no. of poles P, i.e. A = P. Expression ΦZN/60 (P/A) reveals tha the generated e.m.f. in lap connected machine (equal to Φ.ZN) is independent of the no. of poles.

Posted Date: 7/23/2012 1:50:57 AM | Location : United States

Related Discussions:- Developed diagram of simplex progressive 2 layer lap winding, Assignment Help, Ask Question on Developed diagram of simplex progressive 2 layer lap winding, Get Answer, Expert's Help, Developed diagram of simplex progressive 2 layer lap winding Discussions

Write discussion on Developed diagram of simplex progressive 2 layer lap winding
Your posts are moderated
Related Questions
In most real signal processing applications the measured signals can not be described by an analytical expression. In addition, by the Wold decomposition theorem a stationary signa

You are required to design and document  the hardware design  for a 68HC12D60 based Lift Control Unit (LCU). This design includes  the Input/Output hardware for interfacing with  l

Q. What are the advantages and disadvantages of a R-C coupled amplifier. Advantages · It has excellent frequency response. The gain is constant over the audio frequency ra

The no-load and blocked-rotor tests on a three phase, wye-connected induction motor yield the following results: • No-load test: line-to-line voltage 400 V, input power 1770 W,

Binary Multiplication Multiplication can be seen as multiple additions. For  example  if we  have to multiple 4 and 8 we can  8, 4  time to get the  solution. Actually this  conc

This question investigates the effect of extending the data set with zero-padding & of the appropriate time in the workflow to apply a window function. To get finer resolution in t

A pure sine wave with a frequency of 100Hz is sampled at 150Hz. At which one of the following frequencies would you expect an alias?

Consider the arrangement shown in Figure. A conductor bar of length l is free to move along a pair of conducting rails. The bar is driven by an external force at a constant velocit