DC machine Part -2

far wide applications. So it is DC machines have a lot of control and because of this they find large number of applications. Wherever you require a quick response, so wherever. 300 change of torque and speed we use the same machines so to sum up.

Please find them still in large number of applications where ever you require a quick response wherever required sudden changes in torque and speed and also continuous change that takes place for motoring operations. So in view of these very important advantages, we find DC machines in automotive electronics,. So you find the costumes the supply in an in a automotive.

electric vehicle are a normal road vehicle or a car is battery. We find large number of DC machines in electric in automatic electrics. We find them in mining where considerable amount of speed control is required for several Drive applications. We find them in earth-moving equipment. We find them in still rolling Mills and aluminium rolling bills. That means metallurgical applications because it

require change of speed then we also use them in robotics for quick response for for movement of several parts, and they are still extensively uses electric traction or electric trains. The DC machines are being used. Then they they are used in lifts and highest and you find them in entertainment Electronics like your audios video system, wherever you require a movement of the drives, they are all using DC machines supplied power through the batteries are from a DC source.

We also find them extensively in computers this small DC machines for either variable speed operation or a fixed speed of pressure. So we find that these machines still have very wide applications. typically power 4 adjustable speed drives. Okay now we having learned broadly historically what it is about what are the functions of this machine speciality of Risa machines and typical uses of DC machines. We can go further into how do they look like and how they are made and after that we can know more about its internal working principles and so on so

Recalling. We will continuously be using certain terminologies as in any electrical machine. So we use for example the terminology in electrical machines. We use State arrest History part rotor rotating part and the air gap which is the space between the stator and rotor and we also use the terminology called a frame and you Oak frame or the yolk is the one which carries the stator are the stator is fixed inside the frame of the yolk and we use the terminology called decor and whining. The core is the one which part carries the magnetic flux and winding is a one which carries the electric current. Okay, and there are several types of windings which are used in in electrical machines. They are Lumpur winding concentrated winding distributed winding.

concentrate curve overlap windings and so on there are single are winding double are widening. So there are different types of windings when we discuss about Armature windings. We will know about this so the windings are in all machines. You can say you take copper wires make turns and have certain number of turns to make a coil and interconnect the coils to make the windings. So that is the the sequence of providing the electrical winding component in an electrical machine now we also have continuous the use the term Armature and field they are mature is a part which is producing power whereas a field is a part which is producing flux in all the electrical machines. We require a flux producing component and the power producing component because in some there could be some intermixing of the two but in geese emissions they are fairly

structure that there is a separate our culture, which is rotating and a separate field which is stationary. Okay. We also continuously use a terminology. Called motoring than generating. Okay, so the Motoring.

operation in the generate in operation information in Motoring it is taking electrical power giving out mechanical Power and generating. It is taking mechanical Power and giving out electrical power if you want to be a little more elaborate, this is a motoring operation. There is a motor which takes electrical energy and also supplies the molecular energy losses and remaining goes

mechanical energy. So this is the motoring convention then on the other hand if it is a generating. this generator takes mechanical energy. It also supplies losses energy losses, and then it gives out electrical energy. And so this is DC machines also will will work both in the motoring and generating boards. So for we identify that any machine must have an electrical

ordered a mechanical Port that means mechanical Port is a shaft through which either you can take out mechanical energy are put in mechanical energy. Are you have an electrical Port basically their electrical terminals which are in the machines through which you can pass a current or take out a current. Okay, apply a voltage. age are take out the voltage as in a generator.

We also of course the in general we use accessing the rotor we use to mechanism one is called a slip ring Arrangement under is called a commutator segments because you require a brush stationary brush in either case in a DC machine we use a commutator arrangement in which we have a brush through which you apply a

The Liturgy I’ll take out electrical energy and this commutator converts the frequency from DC to AC and vice versa.