Losses in dc shunt machine

5,693 views

Published on

Published in: Business, Technology
0 Comments
3 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
5,693
On SlideShare
0
From Embeds
0
Number of Embeds
2
Actions
Shares
0
Downloads
45
Comments
0
Likes
3
Embeds 0
No embeds

No notes for slide

Losses in dc shunt machine

  1. 1. COMPUTE AND SEPARATE THE LOSSES IN DC SHUNT MACHINE By N.Tejaswani
  2. 2. LOSSES MEANS………… • The basic function of a dynamo is the conversion of energy, either from mechanical to electrical form or from electrical to mechanical form. Whole of the input to the dynamo is not converted into useful output energy but a part of the input energy is converted into heat and is lost for the useful output purpose of the machine. The energy converted into heat is called the ENERGY LOSS.
  3. 3. TYPES OF LOSSES………. • Copper Losses or Electrical Losses • Core Losses or Iron Losses • Brush Losses • Mechanical Losses • Stray-Load Losses
  4. 4. COPPER OR ELECTRICAL LOSSES… These losses are the winding losses because these occurs in the winding of the machine. Armature current losses= = Ia 2Ra Copper losses in shunt field of a machine=Ish 2Rsh Copper losses in interpole winding=Ia 2Ri Copper losses in a series field machine=Ise 2Rse Copper losses in a compensating windings=Ia 2Rc
  5. 5. CORE LOSSES OR IRON LOSSES… These losses are also called as magnetic losses. These losses are constant about 20% of a full load losses Core losses are of two types 1. Hysteresis losses 2. Eddy current losses
  6. 6. BRUSH LOSSES… Power loss at the brush contacts between the copper commutator and the carbon brushes.
  7. 7. MECHANICAL LOSSES.. The losses associated with mechanical effects are called as MECHANICAL LOSSES. They consists of bearing friction loss and windage loss. These losses are usually very small.
  8. 8. STRAY LOSSES… Stray losses are results from 1. The distortion of flux because of Armature reaction 2. Short circuit currents in the coil, undergoing commutation etc Stray losses are assumed as 1% of full load output power
  9. 9. ANY queries ……..?

×