Mehlala ea Lipotso tse Buisanang ka Inductance le Transformers
Inductance le transformer ke mehopolo e 'meli ea bohlokoa motlakaseng, haholo-holo moelelong oa lipotoloho tsa AC (alternating current). Ho utloisisa hore na li sebetsa joang ho tla thusa lits'ebetsong tse fapaneng tse sebetsang, ho tloha moralo oa potoloho ea elektroniki ho isa lits'ebetsong tsa lisebelisoa tsa lapeng le tsa indasteri. Sehloohong sena, re tla tšohla mehlala ea mathata le litharollo tse amanang le inductance le transformer.
Selelekela sa Inductance
Ho kenella ha motlakase ke bokgoni ba karolo ya motlakase, jwalo ka koili, ba ho hlahisa EMF e hlahisitsweng (matla a electromotive) ha phetoho ya motlakase e phalla ka hara yona. Karolo e nang le ho kenella ha motlakase e bitswa inductor. Yuniti ya ho kenella ha motlakase ke Henry (H).
Foromo ea motheo e amanang le inductance ke:
\[ V_L = L \frac{dI}{dt} \]
Moo:
– \( V_L \) ke motlakase o hlahisoang ke (volts)
– \( L \) ke inductance (Henry)
– \( \frac{dI}{dt} \) ke sekgahla sa phetoho ya hona jwale mabapi le nako (di-ampere ka motsotsoana)
Mohlala oa Potso ea 1: Ho Bala Motlakase o Hlahisitsoeng
Potso:
Inductor e nang le inductance ea 5 H e fuoa motlakase o fetohang ho tloha ho 3 A ho ea ho 6 A ka metsotsoana e 2. Bala motlakase o hlahisoang!
Tharollo:
Taba ea pele, re hloka ho fumana sekhahla sa phetoho ea hona joale (\(\frac{dI}{dt}\)):
\[ I_1 = 3 \, \mongolo{A}, \, I_2 = 6 \, \mongolo{A}, \, \Delta t = 2 \, \mongolo{metsotsoana} \]
\[ \frac{dI}{dt} = \frac{I_2 – I_1}{\Delta t} = \frac{6 – 3}{2} = 1.5 \, \text{A/sec} \]
Joale re nkela boleng bo tsejoang sebaka ka foromo ea motlakase e hlahisitsoeng:
\[ V_L = L \frac{dI}{dt} = 5 \makgetlo a 1.5 = 7.5 \, \mongolo{V} \]
Kahoo, motlakase o hlahisoang ke 7.5 V.
Selelekela ho Transformers
Transformer ke sesebelisoa sa motlakase se sebelisetsoang ho fetola maemo a motlakase oa AC ho tloha boemong bo bong ho ea ho bo bong ho sebelisoa molao-motheo oa induction ea motlakase. Transformer e na le likhoele tse peli, khoele ea mantlha le khoele ea bobeli, tse pota-potileng khubu ea tšepe.
Foromo ea motheo bakeng sa transformer e loketseng ke:
\[ \frac{V_p}{V_s} = \frac{N_p}{N_s} \]
Moo:
– \( V_p \) ke motlakase o hodima khoele ya mantlha
– \( V_s \) ke motlakase o hodima khoele ya bobedi
– \( N_p \) ke palo ea lipotoloho khoeleng ea mantlha
– \( N_s \) ke palo ea lipotoloho khoeleng ea bobeli
Mohlala oa Potso ea 2: Ho Bala Motlakase oa Bobeli
Potso:
Transformer e na le diphetoho tse 500 khoeleng ya mantlha le diphetoho tse 100 khoeleng ya bobedi. Haeba motlakase o kenang khoeleng ya mantlha e le 230 V, motlakase o tswang khoeleng ya bobedi ke ofe?
Tharollo:
Sebelisa foromo e loketseng ea transformer:
\[ \frac{V_p}{V_s} = \frac{N_p}{N_s} \]
Liparamente tse tsejoang ke:
– \( V_p = 230 \, \ mongolo{V} \)
– \( N_p = 500 \)
– \( N_s = 100 \)
Re hloka ho fumana \( V_s \):
\[ \frac{230}{V_s} = \frac{500}{100} \]
Ho nolofatsa karoloana e ka letsohong le letona:
\[ \frac{230}{V_s} = 5 \]
Jwale, rarolla bakeng sa \( V_s \):
\[ V_s = \frac{230}{5} = 46 \, \mongolo{V} \]
Kahoo, motlakase o hlahisoang ho coil ea bobeli ke 46 V.
Mohlala oa 3: Ho Bala Palo ea Liphetoho tsa Bobeli
Potso:
Transformer e theohelang ka tlase e sebediswa ho fokotsa motlakase ho tloha ho 240 V ho ya ho 24 V. Haeba palo ya diphetoho tse koeleng ya mantlha e le diphetoho tse 800, ho na le diphetoho tse kae koeleng ya bobedi?
Tharollo:
Sebelisa foromo e loketseng ea transformer:
\[ \frac{V_p}{V_s} = \frac{N_p}{N_s} \]
Liparamente tse tsejoang ke:
– \( V_p = 240 \, \ mongolo{V} \)
– \( V_s = 24 \, \mongolo{V} \)
– \( N_p = 800 \)
Re hloka ho fumana \( N_s \):
\[ \frac{240}{24} = \frac{800}{N_s} \]
Ho nolofatsa karoloana ka letsohong le letšehali:
\[ 10 = \frac{800}{N_s} \]
Rarolla bakeng sa \( N_s \):
\[ N_s = \frac{800}{10} = 80 \]
Kahoo, palo ea lipotoloho tse koeleng ea bobeli ke lipotoloho tse 80.
Mohlala oa Potso ea 4: Ho Bala Matla ka Transformer e Nepahetseng
Potso:
Transformer e loketseng e na le motlakase oa ho kenya oa 120 V coil ea mantlha e nang le motlakase oa 2 A le motlakase oa ho ntša oa 12 V coil ea bobeli. Bala motlakase o phallang coil ea bobeli le matla a hlahisoang coil ea bobeli.
Tharollo:
Taba ea pele, re bala matla a khoeleng ea mantlha (\(P_p\)):
\[ P_p = V_p \times I_p = 120 \, \text{V} \times 2 \, \text{A} = 240 \, \text{W} \]
Ho transformer e loketseng, matla a mantlha a lekana le matla a bobeli:
\[ P_s = P_p = 240 \, \mongolo{W} \]
Jwale, re bala motlakase o ho coil ya bobedi (\(I_s\)) re sebedisa matla:
\[ P_s = V_s \makhetlo I_s \]
\[ 240 = 12 \makhetlo a I_s \]
Rarolla bakeng sa \(I_s\):
\[ I_s = \frac{240}{12} = 20 \, \mongolo{A} \]
Kahoo, motlakase o phallang ka har'a coil ea bobeli ke 20 A, 'me matla a hlahisoang ka har'a coil ea bobeli ke 240 W.
Boikoetliso
Kamora ho utloisisa mehlala e meng ea ho rarolla mathata a kaholimo, mona ke mathata a mang a ho itloaetsa a ka etsoang ho tebisa kutloisiso ea hau ea inductance le li-transformer.
1. Inductor e nang le inductance ea 10 H e fuoa motlakase o fetohang ho tloha ho 4 A ho ea ho 10 A ka metsotsoana e 3. Bala motlakase o hlahisoang!
2. Transformer e nyolohang ka mohato e na le diphetoho tse 200 khoeleng ya mantlha le diphetoho tse 1000 khoeleng ya bobedi. Haeba motlakase wa ho kenya e le 120 V, motlakase wa ho ntsha ke ofe khoeleng ya bobedi?
3. Palo ea liphetho tse koeleng ea mantlha ea transformer ke liphetho tse 400, 'me palo ea liphetho tse koeleng ea bobeli ke liphetho tse 100. Haeba motlakase o fetang koeleng ea bobeli e le 15 V, motlakase o fetang koeleng ea mantlha ke ofe?
4. Transformer e loketseng e na le motlakase oa ho kenya oa 240 V coil ea mantlha e nang le motlakase oa 3 A le motlakase oa ho ntša oa 60 V coil ea bobeli. Bala motlakase o phallang coil ea bobeli le matla a hlahisoang coil ea bobeli.
Ka ho phethela boikoetliso bona, o tla fumana kutlwisiso e tebileng ea hore na inductance le li-transformer li sebetsa joang le ts'ebeliso ea tsona maemong a fapaneng a sebetsang. Tsebo ena ha e bohlokoa feela lithutong tsa thuto empa hape le likarolong tse fapaneng tsa botekgeniki tsa bophelo ba letsatsi le letsatsi le mosebetsi oa botsebi boenjiniere ba motlakase.
