Misalai Masu Daidaito na Turbin Da Daidaitar DC?

Misali Self Excited DC Generators su ne?

Self-excited DC generator

DC generator mai yawan exciting coil shine self-excited generator, wanda ya faru da initial current a cikin exciting coil. Idan generator ta ci gaba, zai samu karamin magana a kan iron na rotor, wanda zai inda shi a cikin armature kuma tana ba da current a cikin field windings. A farkon lokacin, karamin magnetic field ya bari current mai yau a cikin coil, amma don hana da self-excitation, additional magnetic flux ya sa electromotive force a cikin rotor, saboda haka voltage ya zama daidai har zuwa lokacin da machine ya kasance fully loaded.

Operation mechanism

Karamin magana ta yi damar a cikin iron na rotor. Wannan residual magnetic field a kan main pole ya inda shi a cikin stator coil, wanda ya bari initial current a cikin field winding.

Current mai yau ta fi shi a cikin coil ya haɗa magnetic field. Saboda haka, voltage output da field current suna zama daidai. Wannan cycle ya ci har zuwa lokacin da electromotive force a cikin armature ya fi tsakiya voltage drop a biyu na exciting winding. Amma bayan samun darasi, field pole ya ƙoƙarin, a wannan lokacin ya ci electrical equilibrium, armature electromotive force ba zama daidai ba, kuma current ba zama daidai ba. Resistance na excitation winding tana da darasi mai yawa, a wannan lokacin self-excitation za a iya yi. Wannan resistance value zai iya canzawa saboda electrical parameters na generator.

Type of DC generator

DC generators suna divide domin series winding, parallel winding da compound winding, kowace winding na da arrangement da characteristics mai yawa.

Series Wound Generators

A series wound generators, field da armature winding suna connect in series, wanda ke ɗaukar current a cikin external circuit da windings. Field coil tana da low resistance da take consist of a few turns of thick wire, wanda ke ɗauka current flow as load resistance decreases.

Saboda haka magnetic field da output voltage suna zama daidai a cikin circuit. A wannan type na generator, output voltage varies directly with respect to load current which is not required in most of the application. Saboda haka, such types of generators are rarely used.

Shunt Wound DC Generators

A shunt wound generators, field winding tana connect in parallel to the armature, maintaining consistent voltage across the circuit. Field winding tana da many turns to achieve high resistance, limiting the current passing through it and directing the remainder to the load.

A shunt wound generator, as they are connected parallel, current in the parallel branches are independent of each other. Hence, the output voltage almost constant and if it varies then it varies inversely with respect to load current. This is because of the voltage drop as armature resistance increases. 

Combination Wound Generator

Compound wound generator shine advanced version of series wound generator and shunt wound generator. Working principle na generator tana combine two types so that it prevail over the disadvantages of both. It has both types of winding; series field and shunt field winding. On the basis of their connection, compound wound generators are of two types- short shunt compound generator and long shunt compound generator.

 Long Shunt Compound Generator

Here the shunt field winding tana connect parallel to armature only as shown in figure. Series winding tana connect in series.

 Short Shunt Compound Generator

Here the shunt field winding tana connect parallel to armature only as shown in figure. Series winding tana connect in series.

Advantages of Compound DC Generator

A compound generator, armature voltage decreases automatically, when load current increases, due to which magnetic field produced by shunt winding decreases. But the same increase in load current flows through the series winding causes an increase in the magnetic field. So the decrease in magnetic field in the shunt field is compensated by increase in magnetic field in series field. In his manner, the output voltage remains constant as shown in figure.

 Commutative and Differential Compound DC Generator

As compound wound generator has both the fields-shunt field and series field, their combination makes lot of difference. When series field aided the shunt field, their impact is more and it is said to be commutatively compound wound. On the other hand, if the series field opposes the shunt field, then their impact is less and it is said to be differential compound generator.