Kawaloci na Kokarin Yawan Mote DC: Kawaloci na Zafi da Take da Zafi da Kwarewa

Mataki na DC wani alama ce ke kawo energy masu shi ne zuwa electrical energy na direct current. Wani daga cikin abubuwan da suka fi sani a mataki na DC shine yadda aka iya canza tasirinsa ta hanyar hukuma da suka fi gaba. Wannan yadda kan bayanin tasiri ba a lura a mataki na AC.

Bayanan regulation da control ya tasiri suna mutane. A halin regulation, tasirin motoci ke yin takaice a kan wurare da suke faruwa. Amma a mataki na DC, wannan takaice ke yi a jin da yake ko a jin da yanayin hukuma. Tasirin mataki na DC ana nuna a kan wannan muhimmanci:

Equation (1) ta nuna cewa tasirin mataki na DC yana iya kasancewa wasu abubuwa uku: voltage na supply V, resistance na armature circuit Ra, da flux na field ϕ, wanda yake faruwa a kan current na field.

• A lokacin da muke son hukumomi tasirin mataki na DC, ya kamata a duba voltage, resistance na armature, da flux na field. Ana da uku hukumar da za a iya amfani da su don hukumomi tasirin mataki na DC, kamar yadda ake bayyana a nan:

• Variation of Resistance in the Armature Circuit (Armature Resistance or Rheostatic Control)

• Variation in Field Flux (Field Flux Control)

• Variation in Applied Voltage (Armature Voltage Control)

Babu bayanai masu ƙarin game da cikin waɗannan hukumar da za a iya amfani da su don hukumomi tasirin mataki na DC a nan.
Armature Resistance Control of DC Motor (Shunt Motor)
Tambayar na connection diagram don amfani da armature resistance control a mataki na shunt motor yana nuna a nan. A wannan hukuman, an sanya variable resistor Re a cikin armature circuit. Yadda aka canza value na variable resistor ba zai tabbatar da magnetic flux saboda field winding yana haɗa da supply mains.

Speed current characteristic na shunt motor yana nuna a nan.

Series Motor
Tara da tambayar na connection diagram don hukumomi tasirin mataki na DC series motor a cikin hukumar da ya kasancewa armature resistance control method.

Idan resistance na armature circuit yana canza, yana iya tabbatar da current na circuit da kuma magnetic flux a cikin motoci. Drop na voltage a kan variable resistor yana ƙasa voltage na armature. Saboda haka, wannan ƙasancewar voltage na armature yana ƙasa tasirin motoci.

Speed - current characteristic curve na series motor, wanda yana nuna nasararsa a kan tasirin motoci da current na ita, yana nuna a nan.

Idan value na variable resistance Re yana ƙara, motoci yana yi tasirin ƙarami. Saboda variable resistance yana ƙara armature current, yana bukaci a yi engineering don ya iya ƙara full - rated armature current baya da ya ƙara ko kusa.

Disadvantages of the Armature Resistance Control Method

• Yawan electrical power yana ƙasa heat a cikin external resistance Re, wanda yake haifar da inefficiencies da energy waste.

• Wannan hukumar da ya kasancewa armature resistance control yana iya ƙara tasirin motoci ta hafin tasirin da ake yi a jin, ba zai iya ƙara tasirin da ake yi a jin.

• Don irin value na variable resistance, degree na ƙarancin tasiri ba zai ɗauke amma yana ƙara da load na motoci, wanda yake haifar da matsaloli a yi precise speed regulation.

• Saboda inefficiencies da limitations, wannan hukumar da ya kasancewa speed - control yana iya amfani da su don motors mai ƙarin.

Field Flux Control Method of DC Motor

Magnetic flux a cikin mataki na DC yana faruwa a kan field current. Saboda haka, hukumomin tasiri a cikin wannan hukumar yana iya amfani da adjustment na magnitude na field current.

Shunt Motor

A cikin shunt motor, an sanya variable resistor RC a cikin series na shunt field windings, kamar yadda ake bayyana a nan. Wannan RC yana da sunan shunt field regulator, wanda yana taka rawa a canza field current da kuma magnetic flux na motoci.

Shunt field current yana nuna equation a nan:

Idan variable resistor RC an sanya a cikin field circuit, yana ƙara flow na field current. Saboda haka, magnetic flux na field windings yana ƙara. Wannan ƙarancin flux yana ƙara tasirin motoci, wanda yake ƙara. Saboda haka, motoci yana yi tasirin ƙarami.

Wannan characteristics yana taimakawa a biyu abubuwa. Kadan, yana iya ƙara tasirin motoci ta hafin tasirin da ake yi a jin, wanda yake taimakawa a fili da applications da suka bukata tasirin ƙarami. Ta haka, yana iya amfani da su don ƙara drop na tasiri wanda yake faruwa idan motoci yana ƙara load, wanda yake ƙara a yi consistent speed a cikin varying load conditions.

Speed - torque curve na shunt motor, wanda yana nuna relationship a kan tasirin motoci da torque na ita, yana nuna a nan. Wannan curve yana ba da valuable insights a kan performance characteristics na motoci a cikin different operating scenarios idan field flux control method yana amfani da ita.

Series Motor

A cikin series motor, canza field current yana iya amfani da one of two methods: either by utilizing a diverter or by implementing tapped field control.

By Using a Diverter

Kamar yadda ake bayyana a nan, an sanya variable resistance Rd a parallel na series field windings. Wannan configuration yana iya ƙara distribution na current a cikin circuit, wanda yake ƙara strength na magnetic field na series field windings.

Parallel resistor a cikin wannan setup yana da sunan diverter. Idan diverter na variable resistance Rd an sanya, yana ƙara fraction na main current away from series field windings. Saboda haka, primary function na diverter shine ƙara magnitude na current passing through field winding. Idan field current yana ƙara, magnetic flux na field yana ƙara. Wannan ƙarancin flux yana ƙara tasirin motoci.Tapped Field ControlThe second approach for altering the field current in a series motor is through tapped field control. The corresponding connection diagram, which illustrates the specific electrical connections and components involved in this method, is presented below.

A cikin tapped field control method, ampere - turns yana canza da changing number of active field turns. Wannan particular configuration yana da applicability a electric traction systems. By manipulating the number of field turns, magnetic field flux na field winding yana canza, wanda yake ƙara precise control over the motor's speed.

Speed - torque characteristic curve na series motor, wanda yana nuna relationship a kan tasirin motoci da torque na ita, yana nuna a nan. Wannan curve yana ba da valuable insights a kan performance capabilities na motoci idan tapped field control method yana amfani da ita, helping engineers and technicians understand how the motor responds to changes in load and speed settings.

Advantages of Field Flux Control
Field flux control method yana da advantages, kamar yadda ake bayyana a nan:

• Ease of Use: Wannan approach yana da straightforward and user - friendly, facilitating simple implementation and operation.

• Low Power Loss: Given that the shunt field typically has a relatively small current requirement, the power dissipated within the shunt field remains minimal, contributing to improved overall efficiency.

• Speed Increase Mechanism: Due to the saturation of the iron core in the magnetic circuit, the magnetic flux generally cannot be increased beyond its normal value. As a result, field flux control primarily focuses on weakening the field, which effectively leads to an increase in the motor's rotational speed.

• Controlled Application Range: However, it's important to note that this method is applicable only within a restricted range. Excessive weakening of the field can lead to instability in the motor's operation, limiting its use to specific scenarios where precise control and stability are crucial.