Universal motors can operate on both AC and DC power supplies. They have series-wound armatures and field windings which allow them to generate high torque. On DC power, they run at a higher speed than on AC power of the same voltage due to reactance voltage drop. They consist of a stator with field poles and coils, and an armature made of skewed slots housing a commutator and brushes. Regardless of the power source, the motor produces torque in the same direction through synchronized reversal of the magnetic field and armature current. Universal motors are compact and lightweight but noisy, with efficiencies around 30% for smaller models. They are commonly used in appliances requiring variable speed control like fans,
HVE UNIT IV MEASUREMENT OF HIGH VOLTAGES AND HIGH CURRENTS.pptxMuthuKumar158260
The document discusses various techniques for measuring high voltages and currents. It describes methods such as using high resistance series connections with microammeters, resistance potential dividers, capacitance potential dividers, generating voltmeters, and electrostatic voltmeters. It also discusses techniques for measuring high alternating currents and impulse voltages, including the use of peak voltmeters and sphere gaps.
An Active Input Current Waveshaping with Zero Switching Losses for Three-Phas...IDES Editor
(1) The document presents an active switching network for a three-phase AC to DC boost converter that achieves zero switching losses while maintaining unity input power factor.
(2) The network uses capacitors and diodes to maintain zero voltage across the switches during turn-off, limiting current rise during turn-on.
(3) The network allows the boost converter to directly control the DC bus voltage by varying the duty cycle at a constant switching frequency, improving efficiency.
2016.10.24 studieveiledning i 2 timer web i elektroteknikk kap.4 - versjon ...Sven Åge Eriksen
2016.10.24 studieveiledning i 2 timer web i elektroteknikk kap.4 - versjon m - 2016.10.17 - 1.klasser Sven Åge Eriksen ELEKTROTEKNIKK KAPITTEL 4 FAGSKOLEN TELEMARK
Single Phase Induction Type Energy MeterVishal Thakur
The document summarizes the construction and working of a single phase induction type energy meter. It consists of a driving system, moving system, braking system and registering system. The driving torque is proportional to the supply voltage, load current and their phase difference, causing the disk to rotate. The number of rotations is proportional to the energy consumed. Potential errors include incorrect fluxes/phase angles and friction changes. Adjustments include preliminary light load and creep adjustments to calibrate the meter.
Bi-Toroid Transformer Technology (BiTT) Principle of OperationThane Heins
The Bi-Toroid Transformer (BiTT) uses a novel design that improves upon conventional transformers. It places the primary coil in the center of a three-phase transformer, with the two secondaries on either side. An outer toroid connects the secondaries but isolates them from the primary. This allows energy transfer from primary to secondaries in one direction only, like a magnetic diode. With resistive loads, the BiTT primary power factor and current do not change from no-load to on-load conditions. This increased efficiency can lower power losses by 30% or more. Potential applications include battery chargers and electric vehicles.
A transformer is a device that converts alternating voltages from one level to another. It works on the principle of mutual induction between two coils linked by a magnetic field. A step-up transformer increases voltage and decreases current, while a step-down transformer decreases voltage and increases current. Real transformers are not 100% efficient due to energy losses from copper windings, flux leakage, hysteresis in the iron core, and eddy currents. However, transformers remain essential for power transmission and applications requiring different voltage levels.
1) The document discusses different types of armature windings for DC motors and generators. It describes single layer and double layer windings, where double layer windings have two coil sides per slot.
2) Key terms related to armature windings are defined, including commutator pitch, pole pitch, and coil span/pitch. Full-pitched and fractional-pitched coils are also explained.
3) The main types of DC armature windings covered are lap and wave windings. Lap windings are used for high-current applications and have a commutator pitch of 1, while wave windings are used for high-voltage applications and have a commutator pitch of around 2 pole
The document summarizes key aspects of induction motors. It describes that induction motors are the most commonly used motors that operate on the principle of electromagnetic induction. It discusses the basic construction of induction motors including the stator, rotor, and types depending on input supply or rotor design. The document also explains the principle of operation where rotating magnetic flux in the stator induces current in the rotor and causes it to rotate at a slower synchronous speed. Finally, it provides some common applications of single and three-phase induction motors.
Universal motors can operate on both AC and DC power supplies. They have series-wound armatures and field windings which allow them to generate high torque. On DC power, they run at a higher speed than on AC power of the same voltage due to reactance voltage drop. They consist of a stator with field poles and coils, and an armature made of skewed slots housing a commutator and brushes. Regardless of the power source, the motor produces torque in the same direction through synchronized reversal of the magnetic field and armature current. Universal motors are compact and lightweight but noisy, with efficiencies around 30% for smaller models. They are commonly used in appliances requiring variable speed control like fans,
HVE UNIT IV MEASUREMENT OF HIGH VOLTAGES AND HIGH CURRENTS.pptxMuthuKumar158260
The document discusses various techniques for measuring high voltages and currents. It describes methods such as using high resistance series connections with microammeters, resistance potential dividers, capacitance potential dividers, generating voltmeters, and electrostatic voltmeters. It also discusses techniques for measuring high alternating currents and impulse voltages, including the use of peak voltmeters and sphere gaps.
An Active Input Current Waveshaping with Zero Switching Losses for Three-Phas...IDES Editor
(1) The document presents an active switching network for a three-phase AC to DC boost converter that achieves zero switching losses while maintaining unity input power factor.
(2) The network uses capacitors and diodes to maintain zero voltage across the switches during turn-off, limiting current rise during turn-on.
(3) The network allows the boost converter to directly control the DC bus voltage by varying the duty cycle at a constant switching frequency, improving efficiency.
2016.10.24 studieveiledning i 2 timer web i elektroteknikk kap.4 - versjon ...Sven Åge Eriksen
2016.10.24 studieveiledning i 2 timer web i elektroteknikk kap.4 - versjon m - 2016.10.17 - 1.klasser Sven Åge Eriksen ELEKTROTEKNIKK KAPITTEL 4 FAGSKOLEN TELEMARK
Single Phase Induction Type Energy MeterVishal Thakur
The document summarizes the construction and working of a single phase induction type energy meter. It consists of a driving system, moving system, braking system and registering system. The driving torque is proportional to the supply voltage, load current and their phase difference, causing the disk to rotate. The number of rotations is proportional to the energy consumed. Potential errors include incorrect fluxes/phase angles and friction changes. Adjustments include preliminary light load and creep adjustments to calibrate the meter.
Bi-Toroid Transformer Technology (BiTT) Principle of OperationThane Heins
The Bi-Toroid Transformer (BiTT) uses a novel design that improves upon conventional transformers. It places the primary coil in the center of a three-phase transformer, with the two secondaries on either side. An outer toroid connects the secondaries but isolates them from the primary. This allows energy transfer from primary to secondaries in one direction only, like a magnetic diode. With resistive loads, the BiTT primary power factor and current do not change from no-load to on-load conditions. This increased efficiency can lower power losses by 30% or more. Potential applications include battery chargers and electric vehicles.
A transformer is a device that converts alternating voltages from one level to another. It works on the principle of mutual induction between two coils linked by a magnetic field. A step-up transformer increases voltage and decreases current, while a step-down transformer decreases voltage and increases current. Real transformers are not 100% efficient due to energy losses from copper windings, flux leakage, hysteresis in the iron core, and eddy currents. However, transformers remain essential for power transmission and applications requiring different voltage levels.
1) The document discusses different types of armature windings for DC motors and generators. It describes single layer and double layer windings, where double layer windings have two coil sides per slot.
2) Key terms related to armature windings are defined, including commutator pitch, pole pitch, and coil span/pitch. Full-pitched and fractional-pitched coils are also explained.
3) The main types of DC armature windings covered are lap and wave windings. Lap windings are used for high-current applications and have a commutator pitch of 1, while wave windings are used for high-voltage applications and have a commutator pitch of around 2 pole
The document summarizes key aspects of induction motors. It describes that induction motors are the most commonly used motors that operate on the principle of electromagnetic induction. It discusses the basic construction of induction motors including the stator, rotor, and types depending on input supply or rotor design. The document also explains the principle of operation where rotating magnetic flux in the stator induces current in the rotor and causes it to rotate at a slower synchronous speed. Finally, it provides some common applications of single and three-phase induction motors.
Datakommunikasjon dispersjon sven åge eriksen sven age eriksen Fagskolen Telemark singelmodus multimodus fiber transmisjonsmedier analoge digitale signaler tvinnet parkabel koaksialkabel koder nrz manchester ami kode modulasjon demodulasjon modem
Datakommunikasjon Elektronisk kommunikasjon sven åge eriksen fagskolen telemark LAN WAN www world wide web modem graham bell samuel morse local area network wide area nettwork modem telstar
2016.12.21 host test og host - digital og analog v3 losningsforslag v31Sven Åge Eriksen
Sven åge eriksen sven age eriksen fagskolen telemark digital elektronikk analog elektronikk operasjonsforsterker diode transistor zenerdiode rele psu transistor likeretterbro
2. STØRRELSESSYMBOLER FOR MAGNETISME:
.
Φ = Magnetisk fluks (phi) målt i Weber (Wb)
B = Magnetisk flukstetthet målt i Tesla (T)
H = Magnetisk feltstyrke målt i ampere per meter (A/m)
L = Induktans (selvinduktans) i spole, målt i henry (H)
Rm = Reluktans, magnetisk resistans målt i 1/Henry (1/H)
Λ = Permeans (lamda) magnetisk ledningsevne målt i henry (H)
μ0 = Permeabilitetskonstant for vakuum i henry per meter (H/m)
μr = Relativ permeabilitet (ubenevnt, se verdier i tabell)
μ = μ0 · μr = Permeabilitet målt i henry per meter (H/m)
44. Når strømmen er av eller på, induseres ikke
spenning til den andre spolen.
Magnetfeltet endrer seg ikke ved lik strøm.
Da er det ingen endring av den magnetiske fluksen.
Ved endring av strømmen, induseres spenning til
den andre spolen.
Magnetfeltet endrer seg ved endring av strømmen.
Den magnetiske fluksen endrer seg ved endring av
strømmen.
48. Lenz' lov sier at en indusert strøm har en slik
retning at de kreftene som oppstår vil motvirke
inngrepet som induserer strømmen.
Lenz' lov er helt sentral innenfor elektromagnetisk
induksjon, og gir opphavet til minusfortegnet
i Faradays lov. Lenz' lov ble formulert av
fysikeren Emil Lenz i 1834
https://no.wikipedia.org/wiki/Lenz'_lov
53. STØRRELSESSYMBOLER FOR MAGNETISME:
.
Φ = Magnetisk fluks (phi) målt i Weber (Wb)
B = Magnetisk flukstetthet målt i Tesla (T)
H = Magnetisk feltstyrke målt i ampere per meter (A/m)
L = Induktans (selvinduktans) i spole, målt i henry (H)
Rm = Reluktans, magnetisk resistans målt i 1/Henry (1/H)
Λ = Permeans (lamda) magnetisk ledningsevne målt i henry (H)
μ0 = Permeabilitetskonstant for vakuum i henry per meter (H/m)
μr = Relativ permeabilitet (ubenevnt, se verdier i tabell)
μ = μ0 · μr = Permeabilitet målt i henry per meter (H/m)
57. Induktans L for spole:
Induktans sier noe om spolens evne til å
oppta energi og evnen til å motvirke
strømendringer.
Induktansen er en konstant for hver enkelt
spole.
Energien opptatt i en spole er kinetisk
energi.
69. Diode som lader ut spolen, når denne mister
strømmen når transistoren stenger.
Overspenningen som bygges opp må ha en
plass å gjøre av seg for ikke å ødelegge
transistoren.
72. Induktans for spole:
For en sylindrisk, jevnt viklet spole
gjelder tilnærmelsesvis denne formelen:
l
AN
L
2
73. L = Induktivitet eller induktans i [H = Henry]
μ0 = absolutt permeabilitet (4·π·10−7 [H/m])
μr = relativ permeabilitet til materialet i kjernen.
For vakuum er verdien lik 1, og den er ikke så
mye forskjellig for de fleste andre materialer som
ikke er ferromagnetiske.
N = antall vindinger (uten benevning)
A = Arealet til kjernen [m2]
l = lengden til spolen i [m]. l
AN
L
2
81. Disse to spolene seriekobles, hva blir den
totale induktansen ?
L= 10mH L= 90mH
82. Disse to spolene seriekobles, hva blir den
totale induktansen ?
L1= 10mH L2= 90mH
LSERIE = L1 + L2= 100mH
83. Legg merke til at ved seriekobling av spoler som ikke virker
magnetisk inn på hverandre, så er den totale induktansen
STØRRE enn den største enkeltinduktansen i kretsen !
84. Disse to spolene kobles i parallell, hva blir den
totale induktansen ?
L1= 10mH L2= 90mH
88. Legg merke til at ved parallellkobling av spoler som ikke virker
magnetisk inn på hverandre, så er den totale induktansen
MINDRE enn den minste enkeltinduktansen i kretsen !
89. Oppgave:
2 stk spoler med hver på induktansen 100mH er seriekoblet, hva er
seriekoblingens induktans ?
90.
91. Oppgave: Vise utregning !
2 stk spoler med hver på induktansen 100mH er seriekoblet, hva er
seriekoblingens induktans ?
92. Oppgave:
2 stk spoler med hver på induktansen 100mH er seriekoblet, hva er
seriekoblingens induktans ?
LTOTAL =
L1 + L2 =
100mH + 100mH
= 200 mH
93. Oppgave:
2 stk spoler med hver på induktansen 100mH er parallellkoblet,
hva er parallellkoblingens induktans ?
94.
95. Oppgave:
2 stk spoler med hver på induktansen 100mH er parallellkoblet,
hva er parallellkoblingens induktans ?
96. Oppgave: Vise brøkregning: Metode 1
2 stk kondensatorer med hver på kapasitansen 100μF er
seriekoblet, hva er seriekoblingens kapasitans ?
1
𝐿 𝑇𝑂𝑇𝐴𝐿
=
1
𝐿1
+
1
𝐿2
L TOTAL =
𝐿1 ·𝐿2
𝐿1+𝐿2
97. Oppgave: Vise brøkregning: Metode 2
2 stk kondensatorer med hver på kapasitansen 100μF er
seriekoblet, hva er seriekoblingens kapasitans ?
1
𝐿 𝑇𝑂𝑇𝐴𝐿
=
1
𝐿1
+
1
𝐿2 L TOTAL =
𝟏
𝟏
𝑳𝟏
+
𝟏
𝑳𝟐
98. Oppgave: Vise utregning !
2 stk spoler med hver på induktansen 100mH er parallellkoblet,
hva er parallellkoblingens induktans ?
99. Oppgave:
2 stk spoler med hver på induktansen 100mH er parallellkoblet,
hva er parallellkoblingens induktans ?
1
𝐿 𝑇𝑂𝑇𝐴𝐿
=
1
𝐿1
+
1
𝐿2
L TOTAL =
𝐿1 ·𝐿2
𝐿1+𝐿2
L TOTAL =
𝟏𝟎𝟎·𝟏𝟎𝟎
𝟏𝟎𝟎+𝟏𝟎𝟎
mH = 50mH
100. Oppgave 6: TIPS !
2 stk spoler med hver på induktansen 100mH er parallellkoblet,
hva er parallellkoblingens induktans ?
L TOTAL =
𝟏𝟎𝟎·𝟏𝟎𝟎
𝟏𝟎𝟎+𝟏𝟎𝟎
mH = 50mH
NÅR FLERE SPOLER ER PARALLELLKOBLET,
VIL DEN TOTALE INDUKTANSEN TIL KRETSEN
ALLTID VÆRE MINDRE ENN INDUKTANSEN
TIL DEN MINSTE SPOLEN !
SLIK KAN DU SJEKKE SVARET !