What is armature? How to reduce armature reaction?
DC motors have a system of many interconnected drivers, which are mounted on an armature. The armature is made by joining several plates of malleable iron and is cylindrical. It has cut pieces all around, in which the driving groups are kept as horoscopes or punishments. These drivers, according to a certain scheme, are interconnected. This fixed sequence is called armature winding. Different types of coils have specific characteristics, which have specific characteristics of specific types of coils, with distinct advantages.
The magnetic field is also obtained by flowing current from one another in the conduction group. Direct currents in armature drivers of motors are carried by Burroughs. These Burush are, in fact, superimposed on the commutator associated with the armature and associated with the supply. The magnetic fields are associated with the coils.
The coils that produce magnetic fields are commonly called field coils. These coils may be associated with the armature coil in series or associated in parallel or in parallel. It may also be that some of them are in the series range and some in parallel.
Based on this combination of field coils, three different types of direct current motors are obtained.
- Series Motor
- Shunt motor
- Compound motor
In the series motor, the current flowing through the armature also flows in the coil. Hence, its field coil has very few coils of coarse wire. In the shunt motor, only a fraction of the full current flows through the coil, depending on the bolt and resistance of the coil. Therefore, in this region the coil has very high coil of very thin wire, due to which the resistance of this coil is usually several hundred ohms.
Characteristics of direct current motors of different types are also very different and according to them they are also used for different purposes. Shunt motors operate at almost constant speed and their speed variance does not increase with load (load). Therefore, they are used in all those uses where a uniform speed is required. They are very useful for trams, elevators, cranes etc. More force has to be applied before moving a load, but it does not require that much force when it starts moving. Therefore class motors are ideal for these applications and are widely used in railway traction, domestic mixer motor, etc.
For most purposes, shunt and range types are required, which can be achieved by a combined motor.
How to reduce armature reaction?
There are two ways to reduce armature response in DC machines.
- Compensation winding
As we know that the armature passes through this winding due to the flow of the armature.
If we combine another winding with the armature winding in the series then the armature current also passes through this winding. This separate winding is known as compensatory winding.
The current armature undergoing Werning compensation is opposite to the polarity of the winging flux so both these fluxes cancel each other's effects.
So the armature reaction can be minimized by this method.
To reduce the armature reaction, there is another method in which small poles called staples are placed between the main poles of the stator.
The windings of these poles are connected to a series of armature windings, the armature current passes through that winding and the built-in flux.
These two fluxes of armature winding and interpol cancel each other due to the opposite polarity so it reduces the armature reaction.