Armature: Tasharfi Da Fungamai Da Koyarwa

Misalai Armature Ce?

Armature shi ne mu'amala na mutanen kimiyya (ya'ni, motori ko generator) da ya faruwa da alternating current (AC). Armature yana faruwa da AC wanda ya gama da DC (Direct Current) masu kimiyya ta hanyar commutator (wanda ya ci gaba da karamin faruwar current) ko saboda electronic commutation (misali, a brushless DC motor).

Armature tana bayar da cikin da ke da armature winding, wanda tana iya haɗa da magnetic field da aka faru a cikin air gap daga stator zuwa rotor. Stator zai iya zama wata baka (rotor) ko wata mai tsawo (stator).

Sun adda sunan armature a shekarar 19th don nufin “keeper of a magnet”.

Yadda Armature Yake Iya Bincike a Motori Na Kima?

Motori na kima tana badala energy na kima zuwa energy na mekaniki ta hanyar electromagnetic induction. Wannan tana faru idan conductor da ya faruwa da current tana ci gaba da magnetic field, kamar yadda aka bayyana a cikin Fleming’s left-hand rule.

A motori na kima, stator tana faruwa da rotating magnetic field ta hanyar permanent magnets ko electromagnets. Armature, wanda ya fi sani rotor, tana faruwa da armature winding wanda tana haɗa da commutator da brushes. Commutator tana ci gaba da karamin faruwar current a cikin armature winding idan ya ci gaba da karamin faruwar current da ya haɗa da magnetic field.

Haɗin karamin faruwar magnetic field da armature winding tana faruwa da torque wanda tana ci gaba da armature zuwa ci gaba. Shaft da aka haɗa da armature tana bayar da mechanical power zuwa abubuwa masu sauri.

Yadda Armature Yake Iya Bincike a Generator Na Kima?

Generator na kima tana badala mechanical energy zuwa electrical energy ta hanyar principle of electromagnetic induction. Idan conductor tana ci gaba a cikin magnetic field, tana faruwa da electromotive force (EMF) kamar yadda aka bayyana a cikin Faraday’s law.

A generator na kima, armature tana fi sani rotor wanda tana ci gaba da prime mover, misali diesel engine ko turbine. Armature tana faruwa da armature winding wanda tana haɗa da commutator da brushes. Stator tana faruwa da stationary magnetic field ta hanyar permanent magnets ko electromagnets.

Haɗin karamin faruwar magnetic field da armature winding tana faruwa da EMF a cikin armature winding, wanda tana ci gaba da electric current zuwa external circuit. Commutator tana ci gaba da karamin faruwar current a cikin armature winding idan ya ci gaba da karamin faruwar current da ya haɗa da alternating current (AC).

Armature Parts & Diagram

Armature tana da waɗannan abubuwan da suka fiye: core, winding, commutator, da shaft. Duka tana da diagram wanda tana bayyana waɗannan abubuwa.

Armature Losses

Armature a kimiyyoyi na kima tana faruwa da waɗannan losses, wanda tana ci gaba da efficiency da performance. Waɗannan losses sun hada da:

• Copper loss: Wannan tana power loss saboda resistance a cikin armature winding. Tana ci gaba da square of the armature current, kuma tana iya ci gaba da amfani da wires masu goma ko parallel paths. Copper loss tana iya haske ta hanyar formula:

idani Pc tana copper loss, Ia tana armature current, da Ra tana armature resistance.

Eddy current loss: Wannan tana power loss saboda induced currents a cikin core of the armature. Waɗannan currents sun faruwa saboda changing magnetic flux, wanda tana faruwa da heat da magnetic losses. Eddy current loss tana iya ci gaba da amfani da laminated core materials ko ci gaba da air gap. Eddy current loss tana iya haske ta hanyar formula:

idani Pe tana eddy current loss, ke tana constant depending on the core material and shape, Bm tana maximum flux density, f tana frequency of flux reversal, t tana thickness of each lamination, da V tana volume of the core.

• Hysteresis loss: Wannan tana power loss saboda repeated magnetization and demagnetization of the core of the armature. Wannan process tana faruwa da friction da heat a molecular structure of the core material. Hysteresis loss tana iya ci gaba da amfani da soft magnetic materials with low coercivity da high permeability. Hysteresis loss tana iya haske ta hanyar formula:

idani Ph tana hysteresis loss, kh tana constant depending on the core material, Bm tana maximum flux density, f tana frequency of flux reversal, da V tana volume of the core.

Total armature loss tana iya samun da adding these three losses:

Armature efficiency tana iya nufin ratio of the output power to the input power of the armature:

idani ηa tana armature efficiency, Po tana output power, da Pi tana input power of the armature.

Armature Design

Armature design tana fiye da kyau don performance da efficiency na kimiyyoyi na kima, wanda tana ci gaba da waɗannan key factors:

• Number of slots: Slots tana amfani a cikin armature winding don bayar da mechanical support. Number of slots tana ci gaba da type of winding, number of poles, da size of the machine. Generally, more slots tana faruwa da better distribution of flux da current, lower reactance, da losses, da smoother torque. Amma, more slots tana ci gaba da weight da cost of the armature, reduce the space for insulation da cooling, da increase the leakage flux da armature reaction.

• Shape of slots: Slots tana iya zama opened ko closed, depending on whether they are exposed to the air gap or not. Open slots tana easier to wind da cool, amma tana increase the reluctance da leakage flux in the air gap. Closed slots tana more difficult to wind da cool, amma tana reduce the reluctance da leakage flux in the air gap.

• Type of winding: Winding tana iya zama lap wound ko wave wound, depending on how the coils are connected to the commutator segments. Lap winding tana suitable for high-current da low-voltage machines, as it provides multiple parallel paths for current flow. Wave winding tana suitable for low current da high voltage machines, as it provides a series connection of coils da adds up the voltages.

• Size of the conductor: Conductor tana amfani a cikin armature winding don carry the current. Size of the conductor tana ci gaba da current density, which is the ratio of current to cross-sectional area. Higher current density tana faruwa da higher copper loss da temperature rise, amma lower conductor cost da weight. Lower current density tana faruwa da lower copper loss da temperature rise, amma higher conductor cost da weight.

• Length of the air gap: Air gap tana distance between the stator and rotor

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