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RICH DAD POOR DAD BOOK REVIEW

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  RICH  DAD  POOR  DAD  BOOK REVIEW This is amazing book.   • Explodes the myth that you need to earn a high income to become rich • Challenges the belief that your house is an asset • Shows parents why they can't rely on the school system to teach their kids about money • Defines once and for all an asset and a liability • Teaches you what to teach your kids about money for their future financial success It's been nearly 25 years since Robert Kiyosaki’s  Rich Dad Poor Dad  first made waves in the Personal Finance arena. It has since become the #1 Personal Finance book of all time... translated into dozens of languages and sold around the world. Rich Dad Poor Dad  is Robert's story of growing up with two dads — his real father and the father of his best friend, his rich dad — and the ways in which both men shaped his thoughts about money and investing. The book explodes the myth that you need to earn a high income to be rich and explains the difference between working
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Wave Winding in detail

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Wave winding

 We know that, Yc is commutator pitch

  • Here Yc  ≠ 1 but Yc ≈ 2S/P
  • Assume S=16 and P=4. Coil span = S/P =16/4 =4, Yc = 8
  • The first coil is (1-5') and terminated on commutator 1 and 9. The second coil (9-13') to be connected in series with the first and to be terminated on commutator segment (9 + 8 = 17). Since there are only 16 commutator segments so 17 is identical to 1. Hence, we terminate where we started and cannot connect any more coils in series.
  • Our inability to complete the winding, will persist till 2S is a multiple of P. So, we modify the expression for Yc = 2(S ± 1)/P
  • No. of poles, P = 4
  • No. of slots, S = 17
  • Winding pitch, Yc = 2(S+1)/P choosing +1 for progressive winding
  • Yc = 2(17+1)/4 = 9
  • Coil span = S/P = 4

  • First segment (1-5') starts from 1 and ends at 20, where second coil starts and ends on commutator segment-2
  • Between any two consecutive commutator segments (P/2) coils will be present winding progresses like a wave. Hence the name wave winding.
  • Number of commutator segment between positive and negative brushes = S/P
  • Number of coils between positive and negative brushes = (S/P)*(P/2) = S/2
  • So, only 2 brushes core required and each brush divides coil into 2 parallel paths.
Hence, number of parallel paths, A=2.

Back pitch:- The distance between top and bottom coil sides of one coil measured at back of armature is called back pitch, Yb . We give odd numbers to top coil sides and even numbering to bottom coil sides. So, 5' can be numbered as 10.
As for example, for lap winding: Yb = 10 - 1 = 9
For wave winding: Yb =10 - 1 = 9

Front pitch:- The distance between two coil sides connected to same commutator segment is called front pitch, Yf .
For lap: Yf = 10 - 3 = 7 (using commutator segment 2)
For wave: Yf = 19 - 10 = 9 (using commutator segment 10)

Winding pitch:- The distance between two consecutive similar top or bottom coil sides as winding progresses is called winding pitch, Yw .
For lap, Yw = 3-1 = 2 = Yb - Yf
For wave, Yw = 19-10 = 18 = Yb + Yf



Read more>>> Lap Winding

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