Transformers, Generators, Motors & Inductions are powerful Electrical Machines. Their principle operation based on Faraday’s law of Electromagnetic Induction. Which states, “An emf get generated in a conductor when a changing magnetic field links with it”.
A changing magnetic field is produced in two ways. One way is; by moving the conductor inside the magnetic field. Another way is; through changing electromagnetism which is been generated through an inductor energized from AC supply.
Working phenomenon of some of the Electrical Machines; is discussed below :
In Transformers, There is no moving part Instead there are stationary windings on both the sides Primary & secondary. First, alternating current connects across the primary winding. Through which a changing electromagnetic field get created. This field further links with the secondary winding through a common silicon steel stamping. As a result, An emf get generated in secondary winding.
When a load get connected across the secondary winding, Current starts flowing. In the mean time, Secondary winding also produces an Electromagnetic field Which interacts back with primary winding. This phenomenon of Electromagnetic field interaction is known as mutual induction.
In a Normal Induction Motor, There are two sections stator & rotor. Stator is a stationary part Which holds the total armature winding. While The rotor is a moving part Which contains solid conductors inside the silicon steel stamping in a skewed form.
When power connects across the stator, It generates a changing magnetic field. This magnetic field further links with the rotor.
In return, An EMF generates in the rotor. The rotor’s solid conductors are shorted from both ends. This causes heavy current flow across the solid conductor of the rotor. Generated Magnetic field of rotor further try to catch the magnetic field of stator which results rotor starts rotating.
Alternator is a machine which converts mechanical power into Electrical power. In basic alternator configuration, Armature is the stationary part which contains the heavy winding through which heavy load current flows. While rotor holds permanent magnet OR a field winding.
Field winding’s excitation is controlled according to the feedback from alternator. When rotor’s magnetic field links with armature winding, An emf get generated. When a load get connected across it, Current starts flowing.
Whatever the Electrical machine, We are talking about. Winding plays an important role. In this post, We will talk about winding & Its different configurations.
WINDING
Winding is a composition of number of coils which are organized & connected in a particular pattern. Each Coil consist of several number of turns of insulated wires. A Basic winding configuration been explained below through a GIF.
WINDING CONFIGURATIONS
There are multiple winding configuration based on multiple mechanism of working. For better differentiation, We should study the different winding configuration based on power supplies.
There are two types of power supplies AC & DC. Both the power supplies, winding configurations are explained next.
DC POWERED WINDING CONFIGURATION
DC power supply which has only the magnitude component of voltage & current. For winding designing, Only voltage & current parameters are calculated. DC power is a stable power which do not move with respect to time. That’s why DC power do not have changing magnetic field rather it has a stable magnetic field.
When A DC power is applied across the inductive coil, It produces a fixed magnetic field. But as discussed above, Faraday law of Electromagnetic Induction is all depend upon the changing magnetic field. To achieve this changing magnetic field, Commutation arrangement is been adopted Which makes the situation like changing magnetic field. DC power have two winding configuration such as lap winding & wave winding.
AC POWERED WINDING CONFIGURATION
AC power supply consists of both angle & magnitude components of voltage & current. AC powered winding is designed according to phases, Voltage & power rating. According to phases, Winding for AC power is further categorized as single phase & multiphase .
SINGLE PHASE WINDING CONFIGURATION
Single phase compose of single phase & single neutral. It is the potential difference of phase & neutral. Single phase has multiple winding configuration like universal motors, shaded pole motor, starting-running winding configuration.
Universal Motor Winding Configuration
Universal Motor mechanism is having the same commutation armature arrangement which is used in DC power. Only difference is; Its field magnetic field is produced by field windings. Field windings are connected in series with the armature winding.
This configuration can work on both AC as well as DC power supplies. The high speed machines like Hand grinders, Hand dryers & grinding machines uses This type of winding configuration.
Running-Starting Winding Configuration
This configuration is used in Fans & exhaust fans. This is equipped with two coils; Running Winding & Starting Winding. Both the windings are parallelly connected to power supply. Only thing is, Starting winding is connected in series with the capacitor.
Shades pole configuration
3 PHASE WINDING CONFIGURATION
Three phase winding has overall three coils. According to need, winding is connected in a provision so that coil will get the phase potential or line potential.
3 phase has two winding configurations; STAR & DELTA. In Star, three coils are connected so that one end of each coil is connected together Which forms a junction. The remaining three ends are available for the power supply to be connected. Each coil gets a potential difference of line-Neutral.
In Delta, All three coils are connected in series such that each coil gets potential difference of two phases. Both the configurations of the winding been discussed below through a GIF.
SUMMARY
- Faraday’s law of Electromagnetic Induction. Which states, “An emf get generated in a conductor when a changing magnetic field links with it”.
- A changing magnetic field is produced in two ways. One way is; by moving the conductor inside the magnetic field. Another way is; through changing electromagnetism which is been generated through an inductor energized from AC supply.
- Transformers, Generators, Motors & Inductions are powerful Electrical Machines.
- Whatever the Electrical machine, We are talking about. Winding plays an important role.
- Winding is a composition of number of coils which are organized & connected in a particular pattern. Each Coil consist of several number of turns of insulated wires.
- There are multiple winding configuration based on multiple mechanism of working Such winding configuration based on power supplies.
- DC power produces stable magnetic field.
- As discussed Faraday law of Electromagnetic Induction is all depend upon changing magnetic field. To achieve this working principle, DC motors are equipped with armature & commutation arrangement.
- DC winding’s are further categorized as wave winding & lap winding.
- AC power supply consists of both angle & magnitude components of voltage & current.
- AC powered winding is designed according to phases, Voltage & power rating.
- According to phases, Winding for AC power is further categorized as single phase & multi-phase .
- Single phase compose of single phase & single neutral.
- Single phase has multiple winding configuration like universal motors, shaded pole motor, starting-running winding configuration.
- Three phase winding has overall three coils. According to need, winding is connected in a provision so that coil will get the phase potential or line potential.
- 3 phase has two winding configurations; STAR & DELTA.
- In Star, three coils are connected so that one end of each coil is connected together Which forms a junction. The remaining three ends are available for the power supply to be connected. Each coil gets a potential difference of line-Neutral.
- In Delta, All three coils are connected in series such that each coil gets potential difference of two phases.