1 RE1345 RE1345 KONVERSI TENAGA LISTRIK II KONVERSI TENAGA LISTRIK II Vita Lystianingrum Vita Lystianingrum
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RE1345 RE1345
KONVERSI TENAGA LISTRIK II KONVERSI TENAGA LISTRIK II
Vita LystianingrumVita Lystianingrum
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RE1345 RE1345 KONVERSI TENAGA LISTRIK IIKONVERSI TENAGA LISTRIK II
1: Klasifikasi mesin-mesin listrik dan konstruksi 2: Generator sinkron: proses terbangkitnya EMF dan macam-macam
generator sinkron 3: Generator sinkron: berbeban, kerugian tegangan, diagram vektor
untuk pf. lagging, pf. leading 4: Generator sinkron: menentukan voltage regulator dengan metode
EMF dan karakteristik 5: Generator sinkron: kerja paralel 6:7: Motor sinkron: metode start dan pengaruh perubahan arus eksitasi 8: Motor sinkron: torque dan contoh soal 9 & 10: UTS
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ReferencesReferences
1. Theraja, B. L., ‘Electrical Technology’, S. Chand & Company Ltd., 1978.
2. Karady, G., ‘Lecture Notes on Synchronous Generator’, www.eas.asu.edu/~karady/360_pp.html.
3. Zuhal
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Review KTL 1:Review KTL 1:DC MachinesDC Machines
• Generators convert mechanical energy to electric energy.
• Motors convert electric energy to mechanical energy.
• Faraday’s Law
-> Dynamically & statically induced.
• The construction of motors and generators are similar.
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DC generatorDC generator
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DC generatorDC generator
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carbon brushes
DC Motor DC Motor PartsParts
Field magnet
stator
rotor
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AC Generator
http://www.walter-fendt.de/ph11e/generator_e.htm
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DC Generator: AC Generator with Commutator
http://www.walter-fendt.de/ph11e/generator_e.htm
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AC Generators / AlternatorsAC Generators / Alternators
• Same principles as DC generators -> armature winding & magnetic field.
• Armature winding -> statorfield winding -> rotor
**
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Why stationary armature?Why stationary armature?
• Without brush contact->The output current can be led directly from fixed terminals on the stator (armature windings) to the load circuit.
• Easier to insulate stationary armature winding for high AC voltages (may be as high as 30 kV or more)
• Sliding contacts i.e. slip-rings are transferred to the low-voltage, low-power DC field circuit-> easily insulated
• **Armature windings can be more easily braced to prevent any deformation produced by the mechanical stresses
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SYNCHRONOUS MACHINESSYNCHRONOUS MACHINES
Stator Rotor
Connections
Bearing
Stator winding
Rotor winding
Housing ,cooling ducts
Shaft
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SYNCHRONOUS MACHINESSYNCHRONOUS MACHINES
Stator• Laminated iron
core with slots• Steel Housing
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SYNCHRONOUS MACHINESSYNCHRONOUS MACHINES
Stator details• Coils are placed in
slots
• Coil end windings are bent to form the armature winding.
Slots
Coil
End winding
Iron core
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??
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**2 kinds of rotor**2 kinds of rotor
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SYNCHRONOUS MACHINESSYNCHRONOUS MACHINES
Round rotor
Steel ring
DC current terminals
Wedges
Shaft
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SYNCHRONOUS MACHINESSYNCHRONOUS MACHINES
Rotor Details
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SYNCHRONOUS MACHINESSYNCHRONOUS MACHINES
Round rotor
• The round rotor is used for large high speed (3600rpm) machines.
• A forged iron core (not laminated,DC) is installed on the shaft.
• Slots are milled in the iron and insulated copper bars are placed in the slots.
• The slots are closed by wedges and re-enforced with steel rings.
Round rotor
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SYNCHRONOUS MACHINESSYNCHRONOUS MACHINES
Round Rotor Machine
• The stator is a ring shaped laminated iron-core with slots.
• Three phase windings are placed in the slots.
• Round solid iron rotor with slots.
• A single winding is placed in the slots. Dc current is supplied through slip rings.
Concept (two poles)
N S
A
-B
+
A
+C
+
C
-
B
-
A
B
CStator with laminated iron-core
Slots withwinding
Rotor with dcwinding
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Salient rotorSalient rotor
• Usually for low- & medium-speed alternators
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SYNCHRONOUS MACHINESSYNCHRONOUS MACHINES
Salient Rotor Machine• The stator has a laminated
iron-core with slots and three phase windings placed in the slots.
• The rotor has salient poles excited by dc current.
• DC current is supplied to the rotor through slip-rings and brushes.
• Concept (two poles)
N
S
A+
B+
C+B-
A-
C-
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SYNCHRONOUS MACHINESSYNCHRONOUS MACHINES
Construction
• The picture shows the laminated iron core and the slots (empty and with winding).
• The winding consists of copper bars insulated with mica and epoxy resin.
• The conductors are secured by steel wedges.
• In large machines, the stator is liquid cooled.
• The iron core is supported by a steel housing.
• Construction
empty slots
insulated winding
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SYNCHRONOUS MACHINESSYNCHRONOUS MACHINES
Salient pole rotor construction
• The poles are bolted to the shaft.• Each pole has a DC winding.• The DC winding is connected to the slip-rings (not shown).• A DC source supplies the winding with DC through brushes
pressed into the slip ring. • A fan is installed on the shaft to assure air circulation and
effective cooling.
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SYNCHRONOUS MACHINESSYNCHRONOUS MACHINES
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SYNCHRONOUS MACHINESSYNCHRONOUS MACHINES
Construction• Low speed, large hydro-
generators may have more than one hundred poles.
-> relationship between speed & poles
• These generators are frequently mounted vertically.
• The picture shows a large, horizontally arranged machine.
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• Thank You, see you next week
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• Different construction of synch. Gen & DC gen ->
• Which one precedes?
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