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DIRECT CURRENT MACHINES ABSTRACT: D.C.machine is a highly versatile energy conversion device. It can meet the demand of loads requiring high starting torques, high accelerating and decelerating torques d.c.machine is easily adaptable for drives requiring wide-range speed controls and quick circuits. In d.c machines, the field poles are on the stator called yoke .Armature windings and commutator are on the rotor .brushes are pressed on the commutator surface to collect current from commutator These machines are classified into two categories i.e . Generators and motors Generators are mainly used to convert mechanical energy into electrical energy Motors are used to convert electrical energy. to mechanical. Generators are classified into many types depending upon their excitations they are self & separately exited .Again these self exited generators are of three types 1) Series generators 2) Shunt generators 3) Compound generators There are some losses in generators some of them are listed below Frictional losses Iron losses Field winding losses Now-a-days these d.c.machines are applied in many aspects. INTRODUCTION A d.c,machine is a highly versversatile energy conversion device.In normal dc machines, stator pole is not laminated,armature core is always laminated to reduce eddy -current losses d.c.machines used in control systems These d.c machines mainly consists of two types .i.e generators & motors, In the year1821 Michael faraday invented these machines i.e.generators&motors basing on his laws of magnetic induction CLASSIFICATION OF D.C.MACHINES: D.C.machine’s are classified mainly into two types basing on their useful functions D.C Generators D.C Motors D.C.