Tricky but Easy Electrical Engineering!
Definition Average value of AC or alternating current is expressed by that DC current which transfers across any point of circuit the same charge as is transferred by the AC current for the same time. This means, if AC current I in a circuit flows for t sec and charge Q is transferred across any … Read more
Definition Root Mean Square (RMS) value of AC current is defined as the steady or DC current which when flowing through a circuit for a given time period produces the same heat as produced by the AC current flowing through the same circuit for the same time period. RMS value is also known as effective … Read more
The winding used in electrical machine can be broadly classified into two types: Concentrated Winding and Distributed Winding. Concentrated Winding In concentrated type of winding, all the winding turns are wound together in series to form one multi-turn coil. Examples of concentrated winding are field winding for salient pole synchronous machine and DC machine. In … Read more
Definition of Armature Winding Armature winding in an electrical machine is that winding which carries the load current. In other words, it can also be defined as the winding in which emf is generated due to air gap field flux. It should be noted here that, air gap flux or working flux is produced due … Read more
The main difference between lap and wave winding is the manner of connecting the armature winding coil end to the commutator segment. In lap winding the top and bottom coil ends are connected to adjacent commutator segment whereas in wave winding, they are bent in opposite direction and connected to commutator segments which are approximately … Read more
Wave winding posses certain advantages over lap winding. The main advantage of wave winding is requirement of lesser amount of conductor and carbon brushes. This is because the number of parallel path in wave winding is always 2, therefore two carbon brushes are only required. A wave winding may be fitted with as many brushes … Read more
Pitch Factor or Coil Span Factor Pitch Factor or Coil Span Factor is definite as the ratio of emf generated in short pitch coil to the emf generated in full pitch coil. It is denoted by Kp and its value is always less than unity. This factor basically represents the effect of short pitch winding … Read more
Coil Pitch or Coil Span Coil pitch or coil span is defined as the angular distance between the two coil sides of one coil. It is expressed in terms of electrical space degree. Coil pitch is 180 electrical space degree for full pitch coil and less than 180 degree for short pitch coil. A coil … Read more
Definition Distribution factor is defined as the ratio of phasor sum of coil emfs to the arithmetic sum of coil emfs. It is also known as Belt or Breadth factor and denoted by kd. In electrical machine, armature winding is distributed in the slots. It is not concentrated in a single slot. Therefore the total … Read more
Armature winding in an electrical machine is the winding which carries the load current. Under no-load condition, the armature current is zero. But as the machine is loaded, load current flows through the armature winding and creates magnetic flux. The effect of armature winding mmf or flux on the main working flux created by field … Read more