Alternator Training
-
Upload
jayr-maglinao -
Category
Documents
-
view
3.605 -
download
84
Transcript of Alternator Training
Training Department
ALTERNATOR TRAININGErsin ERDALI
June� 06
Ersin ERDALI 2
1. Base Electrical Information2. Alternator Operation Principle3. Alternator Parts and Functions4. Technical Knowledges and Numeral Rules5. Protection Class (IP,H-F)6. 6. TroubleshootingTroubleshooting GuideGuide
INCLUDE OF ALTERNATOR TRAININGINCLUDE OF ALTERNATOR TRAINING
Ersin ERDALI 3
1. Base Electrical InformationElectromagnetic Field :
Ersin ERDALI 4
FaradayFaraday��ss LawLaw ::
1. Base Electrical Information
Any change in the magnetic environment of a coil of wire will cause a voltage (emf) to be "induced" in the coil. No matter how the change is produced, the voltage will be generated. The change could be producedby changing the magnetic field strength, moving a magnet toward oraway from the coil, moving the coil into or out of the magnetic field, rotating the coil relative to the magnet, etc.
Ersin ERDALI 5
Electrical Definations: Resistance, Unit : Ohm (R)
Resistance is a measure of the degree towhich an object opposes the passage of electric current
Measurement Device : Ohmmeter
Voltage, Unit : Volt (V) Voltage is the difference of electrical
potential between two points of an electricalnetwork
Measurement Device : Voltmeter
Current, Unit : Ampere (A) Moving electrons by voltage and flowing
electrons Measurement Device : Ampermetre 1 Ampere : 6,28x1018 electron /s
IxRV
1. Base Electrical Information
CircuitComponent
Ersin ERDALI 6
� Alternating Current (AC) :
AC current is changed way andstrenght by the time.
� Direct Current (DC) :
DC current is not changedway and strenght by thetime.
1. Base Electrical Information
Ersin ERDALI 7
2. Alternator Operation Principle
When the magnetic fieldaround a conductorchanges, a current is induced in the conductor. In a alternator, a rotatingmagnet called the rotorturns within a stationaryset of conductors woundin coils on an iron core, called the stator. Thefield cuts across theconductors, generatingan electrical current, as the mechanical inputcauses the rotor to turn.
Permanent Magnetic Field
Ersin ERDALI 8
2. Alternator Operation Principle
Sine wave current in eachof the coils produces sine varying magnetic field on the rotation axis. Magneticfields add as vectors.
Vector sum of the magneticfield vectors of the stator coilsproduces a single rotatingvector of resulting rotatingmagnetic field.
Ersin ERDALI 9
Magnetic field on the windings induce alternating (AC) voltage in main stator.
2. Alternator Operation Principle
Ersin ERDALI 10
Voltage regulatorsenses induced voltagein main stator to take a referance.
Sensed voltagecompares regulatorsetting values (400 V AC, 50Hz).
Excitation voltagerealize excitation stator via excitation toes of regulator according tothe difference
Referans Giriºleri
Uyartýn Gerilimi DC
Set Deðerleri
2. Alternator Operation Principle
Ersin ERDALI 11
Diodes rectify DC voltage to inducedAC voltage in excitation rotor toincrease permanentmagnet in mainrotor.
Excitation rotor voltage realizesmain rotor windingswhich rectified DC voltage.
Inputs of DiodesExcitationRotor Voltage AC
Output of Diodes MainRotor Voltage DC
2. Alternator Operation Principle
Ersin ERDALI 12
3. Alternator Parts and FunctionsAlternators Which We Use :
Stamford / England(12 toes)
Mecc-Alte Spa / ItalyEco series 12 toes (Out of Eco 28)
Leroy-Somer / France
Ersin ERDALI 13
MainRotor
StatorA.V.R.
RotatingDiodes Plateand Varistor
Alternator
Excitation Rotor
Terminal Box
3. Alternator Parts and Functions
Ersin ERDALI 14
3. Alternator Parts and FunctionsAlternator Parts (MccAlte Eco 37) :
NAME1 real seal2 casing3 grid5 users terminal board7 rear cover8 frame with stator9 front cover9A front cover MD 3510 exciting stator11 rotating diode bridge12 hub13 exciting armature14 rotor15 fan16 exterior flange bearing cover17 drive-end bearing18 interior flange bearing cover19 rear bearing20 terminal box22 diode holder washer
NAME
23 electronic regulator
24 auxiliary terminal board
28 cover stay bolt
39 protection screen
40 fixing ring
42 parallel device
59 coupling hub
60 disc plates
70 radio disturbs suppressor
94 rear case
95 termin.brd.side panel
96 termin.brd.front panel
97 termin.brd.rear panel
98 regulator carrying panel
99 disc blocking ring spacer
104 component-carryng panel
123 ring spacer
143 exciter stay bolt
Ersin ERDALI 15
RFI Suppressor
NeutralPoint
Output
Points
U- V- W
Paralleling
Transformer
A.V.R.
Terminal Box (Mecc Alte ECO 34)
3. Alternator Parts and Functions
Ersin ERDALI 16
A.V.R.
R.F.I. Suppressor
OutputPoints
Terminal Box (Mecc Alte ECO 3)
3. Alternator Parts and Functions
Ersin ERDALI 17
Terminal Box (Stamford P7 Series) :
Terminal Box
3. Alternator Parts and Functions
Ersin ERDALI 18
Main Stator :
� Main stator which is made of high qualitysiliceous laminations is mounted by meansof supporting ribs in a sheet steel body.
� Main stator grooves and main rotor polesare designed to minimize distortion on thewaveform. Main stator windings have a shortened pitch to reduce the harmoniceffects on the waveform.
3. Alternator Parts and Functions
Ersin ERDALI 19
Main Rotor :The rotor is salient-pole type. Damper windings areplaced into the rotor as a standard feature for parallelwork and unbalanced loads. Fan, the main rotor, excitation rotor and the rotating diodes are fitted toshaft . The entire rotor is dynamically balanced.
3. Alternator Parts and Functions
Ersin ERDALI 20
3. Alternator Parts and Functions
Voltage Regulator (AVR) :
Alternator
VoltageRegulator
LOAD
SettingValues
Reference(Sensing)
This is the most important element of the alternator. At asymmetricalloads, the voltage regulator senses three phases as a reference thereforemaximum voltage asymmetry is 5%. Electrical and thermical tests areapplied before mounting on the alternator. The output voltage could be adjusted manually by a potentiometer.
Ersin ERDALI 21
Voltage Regulator (AVR) :
Electronic Voltage Regulator(UVR 6 Mecc Alte)
3. Alternator Parts and Functions
To remotely regulate the voltage there areterminals for potentiometer connection.
Ersin ERDALI 22
Mecc Alte SR 7 UVR 6
Stamford SX 460 SX 440 SX 421 SA 465
S : Self excited
MX 341 MX 321 MA 325M : Permanent Magnet Generator
Voltage Regulators Which We USe :
3. Alternator Parts and Functions
Ersin ERDALI 23
Mecc Alte UVR6 Voltage Regulator Technical Features:
� 170-270 V AC Supply (with + and 2)� Capability to sense 3 phases or 1 phase� Stable for humidity and vibration� Maximum voltage drop 15%� Capability to set voltage-stability� Protection for low frequence and over current
Delay over current protection Yellow Led
Low frequence protection Red Led
Nominal operation Green Led
3. Alternator Parts and Functions
Ersin ERDALI 24
Mecc Alte SR7/2 Voltaj Regulator Setting Potentiometer :
VoltageSetting
StabilitySetting
Factory Settings
(Low speed andover load)
3. Alternator Parts and Functions
Ersin ERDALI 25
Mecc Alte SR7/2 Voltage Regulator Terminal Connections :
Terminal 1 : Excitation windings negative (-) toe.Terminal 2 : It should bridge terminal 3 If SR7/2 regulator supply will be
lower then 160 V AC.Terminal 3 : Excitation windings positive (+) toe and regulator supply.Terminal 4 : Regulator reference voltage.Terminal 5 : Common toe for regulator supply, regulator reference voltage
and external potentiometer connection.Terminal 6 : To bridge terminal 5 for 60 Hz.Terminal 7 : External potentiometer connection.
3. Alternator Parts and Functions
Ersin ERDALI 26
Stamford SX440 Voltage Regulator Technical Features :
Supply voltage 170-250 Vac Frequence 50-60 Hz nominal Output voltage max. 90 Vdc
(207 Vac input) Output Current 4 A DC
(max. 10 seconds 6 A DC) Regulation ± % 1 Operation Temp. -40°C - +70°C
3. Alternator Parts and Functions
Ersin ERDALI 27
Stamford MX321 Voltage Regulator Terminal Connections - 1 : Volts:Setting generator output voltage. Stability:Keeping from voltage oscillation, setting steadystate time . Stability Selection:To provide suitable voltage transient. UFRO:Setting underfrequence protection border. Frequency Selection:Providing for suitable operation of UFROprotection. Droop:Enable voltage droop (5 % on full load). Trim:To provide regulator input and accessories uotput. Exc Trip :Over excitation cutting level (5Vdc - %5, 8-15 sdelayed).
3. Alternator Parts and Functions
Ersin ERDALI 28
DIP:Setting frequence-voltage curve. Over/V:Shuting down excitation voltage WhenÝnput reference voltage to AVR faults(Between terminal E1-E0; 300 Vac, 8-15sdelayed). I-Limit:Maximum short circuit current. Dwell:Voltage tidy up time after on full loaded. RMS:Loading. RAMP:Setting to reach nominal value of outputvoltage by cranking. Factory setting is 3seconds and it�s enough for manyapplications.
3. Alternator Parts and FunctionsStamford MX321 Voltage Regulator Terminal Connections - 2 :
Ersin ERDALI 29
External Voltage Potentiometer Connection :
� Voltage potentiometercan be connectedterminal 1-2 of all AVR for Stamfor alternator.
� Normally thoseterminals are bridged. Remove those bridgewhen potentiometerconnected.� POT = 4,7 K
Stamford MX321 Voltage Regulator
3. Alternator Parts and Functions
Ersin ERDALI 30
Rotating Diode Plate :
Rotating Diode Plate Elements :
1. AC Input2. Rectifier Plate3. Diodes � 3 x Negative4. Diodes � 3 x Positive5. Varistor6. DC Output to Main Rotor7. Plate
�Ac voltage is rectified DC voltage to set the permanentmagnet on main rotor via rotating diodes plate which induceexcitation rotor.
� Rotating diode plate is partitioned positive and negative plateand there are 3 diodes both plates (total 6 diodes).
3. Alternator Parts and Functions
Ersin ERDALI 31
Varistor :Varistors (VDR�s) are a mix of carbon materials that are a highresistance until subjected to a high pressure.
They then becomes a low resistance path to bleed away excessivepressure by allowing lots of amps to momentarily flow throughthe VDR, which has become a momentary low resistance path. This means that the rating of the device based on it only beingasked to conduct for very short period of time and veryintermittently. A VDR that is continually 'clipping� excessivevoltages will get hot and fail.
3. Alternator Parts and Functions
Ersin ERDALI 32
Excitation Stator and Rotor:
� Excitation stator is provided toinduce magnet for excitation rotor by DC signal via voltage regulator(10-15 V).
�On excitation rotor AC voltage is rectified DC voltage via rotatingdiodes plate and varistor. Thus DC Current is induced for permanentmagnet for main rotor.
3. Alternator Parts and Functions
Ersin ERDALI 33
Voltage Regulator Supply Devices - 1 :PMG� Provides a separate fixed source impedencepower to AVR & exciter field that is isolated fromthe generator output and is not influenced byexternal load conditions.
� The isolated PMG power supply of the excitationsystem allows the generator to meet low EMI / RFI suppression levels to meet MIL-STD.461C&VDE Class K.
� PMG provides constant power to supply manualvoltage control of the generator & to supplyovervoltage , overcurrent & over excitationprotection circuits.
�Stamford and Leroy-Somer alternators have gotPMG system which we use.
3. Alternator Parts and Functions
Ersin ERDALI 34
AREPIt is auxiliary windings system to induce AC voltage to supply AVR which is inserted the main stator windings.
Auxiliary windings are thin section. Resistance is lower than mainstator windings.
Mecc Alte alternator has got AREP windings system which we use.
Shunt
AC voltage is provided directly by main stator windings tosupply AVR.
3. Alternator Parts and FunctionsVoltage Regulator Supply Devices - 2 :
Ersin ERDALI 35
When to Choose PMG or AREP :
Whole installation with several circuits Power cut forbidden High rate of distorting loads. Starting of a big motor Marine, hospitals, stand-by duty, standards in some countries. Arep minimum length required PMG existing shunt machine to be upgraded
When to Choose SHUNT :
Single circuit installation Power cut acceptable Self protection alternator
3. Alternator Parts and FunctionsVoltage Regulator Supply Devices - 3 :
Ersin ERDALI 36
3. Alternator Parts and Functions
AREP OR PMGTHE ALTERNATOR CONTROLS THE
SITUATIONDURING 10 SECONDS
THE DEFFECT IS RELEASEDTHE BREAKER TRIPS
- THE POWER SUPPLY IS MAINTAINED
OVERLOAD OR SHORT CIRCUITON THE INSTALLATION
SITUATION
SHUNTTHE ALTERNATOR DOES NOT HOLD
THE SITUATIONDESENERGIZING OF THE ALTERNATOR
- THE POWER SUPPLY IS CUTTEN
AREP
SHUNT
PMG
Ersin ERDALI 37
Brush and Ring Mechanism :
+-+-
+-
3. Alternator Parts and Functions
Ersin ERDALI 38
Alternator Windings Heater:
HeaterHeater
� Humidity can be reducedisolation resistance on alternator windings. In thatcase heater have to insert thewindings for protection.
�Heaters are 54W-220V forMecc Alte ECO 3-28-31-32-34-38 series. Other heaters are65W-220V for ECO 40-43-46 (Optional 50W-110V).
3. Alternator Parts and Functions
Ersin ERDALI 39
Bearing :�Bearing is provided to rotate coupled componentsof alternator mandrel (main rotor, excitation rotor, PMG rotor, rotating diodes, etc.) by stability.
�All alternators in Aksa are single bearing.
3. Alternator Parts and Functions
Ersin ERDALI 40
Fan and Airconditioning :� Alternator windings warme up by and by which induce current inside (J=I2Rt). Warmed windings have to be cooled for efficiency. Fan is used forcooling system.
� Cooling has to be realized for protection of alternator windings. Thereforedon�t close up air intake and drop ball places.
3. Alternator Parts and Functions
Ersin ERDALI 41
Thermic Protection Components :� Thermic sensors use to protect the warmness of windings in alternator (andin electrical motors).
�PTC thermistor uses in Mecc-Alte ECO 37 � 40 � 43 series alternator bystandard.
PTC Thermistor
Bimetal Contact
PT100 ThermicResistor
3. Alternator Parts and Functions
Ersin ERDALI 42
RFI Suppressor :
� RFI (Radio Frequency Interference) is noise vibration in alternatorwindings because of magnetic field(>1 kHz).
� Filter with condenser is used toreduce the noises.
� Standards :
BS EN 50081-50082
VDE 0875
BS 1597
MIL 461
3. Alternator Parts and Functions
Ersin ERDALI 43
Paralleling Transformer:� Paralleling transformer is used forsyncronous operation with other alternatorsand also with the mains.
� This transformer gives for Mecc Alte Eco 40-43 series alternators. It�s optional forother alternators.
3. Alternator Parts and Functions
Ersin ERDALI 44
Blok Diagram For Alternator With PMG :
3. Alternator Parts and Functions
Ersin ERDALI 45
Alternator With PMG :MandrelMain RotorMain StatorBearingExcitation RotorExcitation StatorRotating Diodes Plate and VaristorPMG Rotor and StatorTerminal ConnectionsVoltage RegulatorStator CablesReference CablesPMG CablesExcitation CablesMain Rotor Excitation CablesFan and Air-condition
3. Alternator Parts and Functions
Ersin ERDALI 46
Block Diagram For Alternator With Transformer :
3. Alternator Parts and Functions
Ersin ERDALI 47
4. Technical Knowledges and Numeral Rules
Mains � Generator Voltages :
� Mains in Turkey ;Phase - Neutral : 220 V AC
Phase - Phase : 380 V AC
Frequence : 50 Hz
� During the generator (or transformer) voltage selection, It has to be rate of 5% voltage difference between operating voltage(380 V AC) and generator nominal voltage(400 V AC). For our generators ;Phase - Neutral : 231 V AC
Phase - Phase : 400 V AC
Frequence : 50 Hz
� For USA;
F: 60 Hz
V : 480/270, 208/120,
240/120
�For India and South Africa ;
F : 50 � 25 Hz
Ersin ERDALI 48
Generator Operation Powers :
GENERATOR OPERATION POWERS ACCORDING TO ISO 8528-1 STANDARDS:
4. Technical Knowledges and Numeral Rules
Operation On Standby Power Operation On Prime Power Operation On Continuous Power
Ersin ERDALI 49
Standby Operation(Operation on limited time) :
� This genset operation is used variable loads at no mains.� Load Measure: 110% (1 hour rate of 10% overload per 12 hours).� Annual Operation Time : 500 hours� Application : working centerum, hotels, hospitals, housing estate, resting places, factories and otherrequested stand-by application places.
4. Technical Knowledges and Numeral Rules
Generator Operation Powers :
Ersin ERDALI 50
Prime Operation(Operation on unlimeted time) :
� On unlimited time, maximum power fromgenerator for variable loads.� Load Measure: 90%� Annual Operation Time: Unlimited� Application: Industrial and commercialcompanies, devoloping companies , cogenerationapplications, rental and marine gensets.
4. Technical Knowledges and Numeral Rules
Generator Operation Powers :
Ersin ERDALI 51
Continuous Operation :
� On unlimited time, continuous power viagenerator.� Load Measure: 80%� Annual Operation: Unlimited, continuous.� Application: Continuous base load, mains, cogeneration, parallel operation.
4. Technical Knowledges and Numeral Rules
Generator Operation Powers :
Ersin ERDALI 52
Power Quality and Gauge :�Acceptable values for harmonic distortions accordingto IEC 519-1992 standard;
ForFor VoltageVoltage (V) : (V) : 3% THD3% THD (total (total harmonicharmonic distortiondistortion))
ForFor CurrentCurrent (I) :(I) :5% THD5% THD (total (total harmonicharmonic distortiondistortion))
�More than limited harmonic distortions will be effected big problems and sacrifices.
4. Technical Knowledges and Numeral Rules
Ersin ERDALI 53
Alternator Lifetime : On normaly condition, alternator lifetime is
approximately about 100.000100.000 hours forcontinuous operation
But ;� Over current� Unbalance loads� Operation on low Cos (power factor) loads� Over ambient temperature� Harmonics (because of warmness)� Less air-condition� Operation on pulverulent places�� HumidHumid placesplaces
will be effected shorter than normaly.
4. Technical Knowledges and Numeral Rules
Ersin ERDALI 54
Efficiency Of Alternator :EfficiencyEfficiency = = OutputOutput powerpower / / InputInput PowerPower = kWe / kWm= kWe / kWm
Alternator Losts Iron lost (Hysterysis and Eddy current) Copper lost (Because of windings) Friction lost (ballbearing)
Efficiency of alternator depends on current of load. Efficiency of alternator depends on power factor of
load. Efficiency is increased if Cos will increase. Efficiency is reduced if Cos will reduce.
EfficiencyEfficiency of of alternatoralternator is is approximatelyapproximately aboutabout ;; ForFor 500500--1500 kVA 1500 kVA %90%90--9797 ForFor 00--100 kVA %85100 kVA %85--9393
4. Technical Knowledges and Numeral Rules
Ersin ERDALI 55
Voltage Unbalance Rate:
For example; Output voltages of alternator are about 236, 229, 225 volts;
Voltage unbalance is rated the biggest of 3 phases outputvoltages of alternator (U,V,W) and average output voltage.
4. Technical Knowledges and Numeral Rules
Ersin ERDALI 56
Effecting Alternator Of Voltage Unbalance :
� Because of voltage unbalance, A small magnetic field is induced on alternator windings which is direct opposite main magnetic field.
� Voltage unbalance effects to warm windings up.
Example Calculation :
Temp. Boost = Nominal Temp x 1 + 2(Voltage Unbalance)2
100
Temp. Boost = 80C x 1+2 = 80C x 1,136(2,61)2
100
Temp. Boost = 90,9 C
4. Technical Knowledges and Numeral Rules
Ersin ERDALI 57
Setting Voltage Unbalance With �STAB� Potentiometer :
Genset VoltageUnstable
Critical
Good
Slow
No Load Full Load
4. Technical Knowledges and Numeral Rules
Ersin ERDALI 58
Cos Values Of Electrical Loads :
Electrical Heater 1 Incandescent Lamp 1 3 Phases Motors 0,7-0,9 Fluorescent Lamp 0,3-0,5 Neon Lamp 0,4-0,5 Welder Machine 0,4-0,8
4. Technical Knowledges and Numeral Rules
Ersin ERDALI 59
4. Technical Knowledges and Numeral Rules
The Power Triangle :There are 3 types of electrical powers :
Apparent Power (S, VA)
True Power (P, W)
Reactive Power (Q, VAR)
Ersin ERDALI 60
Electrical Power Formulas:
IU3S
P (kW)
Q (kVAr)S (
kVA)
4. Technical Knowledges and Numeral Rules
The inductor does not use any true power. However, to the generator, theinductor �appears� to be consuming power because there is an oppositionto current (inductive reactance) and voltage drop across it.
The generator power is apparently used by the inductor.The total powerused by the inductor and resistor is called appropriately. Apparent Power.
Apparent power is measured in Volt-Amperes (VA) to distinguish it fromtrue power.Apparent power for an inductive circuit can be found bymultiplying the total current by the applied voltage;
Apparent Power (S, kVA)
Ersin ERDALI 61
True Power (P, kW)
CosSP
P (kW)
Q (kVAr)S (
kVA)
4. Technical Knowledges and Numeral Rules
Electrical Power Formulas:
Inductance and resistance characteristics are both present in industrial motors which consist of many coils of wire.
The coils cause current to lag voltage as in an inductor and becauseof coil length, the motor also has resistance.
AC generator is used to provide power to a motor. The resistor is the only component that comsumes power.
The power used by a resistor is called True Power.
Ersin ERDALI 62
Reactive Power (Q, kVAR)
SinSQ
P (kW)
Q (kVAr)S (
kVA)
4. Technical Knowledges and Numeral Rules
Electrical Power Formulas:
We know that reactive loads such as inductors and capacitorsdissipate zero power, yet the fact that they drop voltage anddraw current gives the deceptive impression that they actuallydo dissipate power. This �phantom power� is called reactivepower, and it is measured in a unit called Volt-Amps-Reactive(VAR).
Ersin ERDALI 63
P (kW)
Q (kVAr) S (kVA)
CosSPIUS
S
3
kVA100
We will calculate full load current for 100 kVAgen-set at Cos=0,8 and Cos=1 ;
4. Technical Knowledges and Numeral RulesExample Calculation For Electrical Powers - 1 :
Ersin ERDALI 64
Firstly we should calculate active power outputof gen-set (Cos=0,8 for gen-set and it�sconstant).
FollowingFollowing thatthat ;;
4. Technical Knowledges and Numeral RulesExample Calculation For Electrical Powers - 2 :
kW808,0100 PPCosSP
Amper 5,1448,04003
80000
3
3
için; 8,0
IICosU
PI
CosIUP
Cos
Ampere
For Cos=0,8
Ersin ERDALI 65
4. Technical Knowledges and Numeral Rules
Amper 6,11514003
80000
3
3
için; 1
idi..kW 80
IICosU
PI
CosIUP
CosP
For Cos =1
Ampere
Example Calculation For Electrical Powers - 3 :
Ersin ERDALI 66
Calculation For Pole Number :
Hz : Hz : FrequenceFrequence N : Engine speed (rpm) K : Pole number120
KNHz
NHzKKNHz
120
120
ExampleExample ::
WeWe willwill calculatecalculate alternatoralternator polepole numbernumber at 1500 at 1500 rpmrpm of of engine engine speedspeed..
4. Technical Knowledges and Numeral Rules
Kutuplu 41500
50120
KK poles
Ersin ERDALI 67
4. Technical Knowledges and Numeral Rules
Suitable Generator Selection - 1 : A gen-set for 1000 kVA will supply a load for 900 kVA andCos = 0,5 . We wiil calculate that; is it suitable power of generator or not? (For all gen-set; Cos = 0,8 constant).
At the first we should calculate true power and reactivepower both gen-set and load. Following that;
For Gen-Set : Sgen = 1000 kVA Cos ö = 0,8
For Load : Sload = 900 kVA Cos ö = 0,5
Ersin ERDALI 68
4. Technical Knowledges and Numeral Rules
Suitable Generator Selection - 2 :
Ersin ERDALI 69
4. Technical Knowledges and Numeral Rules
Suitable Generator Selection - 3 :
Suitable Generator Selection :
Ersin ERDALI 70
Relation Between Voltage and Speed :
� Alternator output voltage is rate of 75% at engine speed rate of 75%.
� Alternator output voltage is rate of 10% at engine lowspeed
� This graph is from Mecc-Alte alternator.
4. Technical Knowledges and Numeral Rules
Ersin ERDALI 71
No voltage reduction if no over load current (speed is fixed).
Voltage is reducing on short circuit. Therefore short circuit opensettings of thermic-magnetic circuit breaker should be according to3ln.
4. Technical Knowledges and Numeral Rules
Relation Between Voltage and Current :
� This graph is from Mecc-Alte alternator.
Ersin ERDALI 72
Windings Connections For 12 Lead Alternators :
Series Star For 3 Phases
Sysytems, 400 Vac (L-L), WithWith neutralneutral, ,
230 Vac (L-N)
Series Delta For 3 Phases
Sysytems, 230 Vac (L-L), No No neutralneutral
Parallel Star For 3 Phases
Sysytems, 200 Vac (L-L), WithWith neutralneutral, ,
115 Vac (L-N)
We use difference connections on alternator to provide difference voltages by easily. Accordingly possibility 115/200/230/400 Volts 50Hz on 12 lead alternators.
4. Technical Knowledges and Numeral Rules
Ersin ERDALI 73
Parallel Delta For 3 Phases
Sysytems, 115 Vac (L-L), No No neutralneutral,,
3 Phases Zig-Zag For 3 Phases Sysytems, 346 Vac (L-L), WithWith neutralneutral.. Alternator output power
multiple 0,8660,866 (346/400)
346 Vac 346 Vac (L(L--L)L)
115 Vac 115 Vac (L(L--L)L)
4. Technical Knowledges and Numeral RulesWindings Connections For 12 Lead Alternators :
Ersin ERDALI 74
Single Phase Parallel Zig-Zag For Single Phase Sysytems, 230 Vac (L-L), WithWith neutralneutral,, Usually this connection uses
in Europe�s countries.
230 Vac 230 Vac (L(L--L)L)
Double Delta For Single Phase Sysytems, 230 Vac (L-L), WithWith neutralneutral,, Usually This connection uses
in Asia�s and America�scountries. This is the sameconnection type of singlephase parallel zig-zag.
230 Vac 230 Vac (L(L--L)L)
4. Technical Knowledges and Numeral RulesWindings Connections For 12 Lead Alternators :
Ersin ERDALI 75
Alternator Electrical Drawing :
AVRU
V
W
170-250 V AC (PMG, AREP, Shunt)
Voltage Regulator Supply
VDC
+
-
Excitation
Stator
Uncontrolled 3 Phases
Bridge Rectifier
VDC
+
-
VARÝSTOR
Main
Rotor
Main
Stator U
V
WReference
Points
PMG Stamford, Leroy-Somer
AREP Mecc Alte
4. Technical Knowledges and Numeral Rules
Excitation
Rotor
Ersin ERDALI 76
5. Protection Class (IP,H-F)IP (Ingress Protection) Code:
The International Protection code, sometimes called the Ingress Protection code, classifies the protection given by an enclosure against the touching of live parts, contact with moving parts and protection against the ingress of solid bodies.
It additionally specifies protection against the harmful ingress of liquids. Two (sometimes 3) digits are used to describe its protection rating, called the IP code.
IP 2 3 C H IP : Ingress Protection 2 : 1. Number (0-6 or X) 3 : 2. Number (0-8 or X) C : Addition letter depends on request ( A,B,C,D) H : Finishing letter depends on request (H,M,S,W)
Ersin ERDALI 77
1.NumberProtection from solid object
0 : Non protected 1 : Protected against solid object greater than 50 mm 2 : Protected against solid object greater than 12 mm 3 : Protected against solid object greater than 2,5 mm 4 : Protected against solid object greater than 1,0 mm 5 : Dust protected 6 : Dust tight
5. Protection Class (IP,H-F)Protection Class According to DIN 40050 Norm:
Ersin ERDALI 78
Protection Class According to DIN 40050 Norm:
2.NumberProtection from moisture
0 : Non protected 1 : Protected against dripping water 2 : Protected against dripping water when tilted up to 15° 3 : Protected against spraying water 4 : Protected against splashing water 5 : Protected against water jets 6 : Protected against heavy seas 7 : Protected against effect of immersion 8 : Protected against submersion
5. Protection Class (IP,H-F)
Ersin ERDALI 79
3.LetterAddition letter depends on request ( A,B,C,D)
For Dangerous Places ; A : With hand B : With finger C : With equipment D: With wire
protection to arrive
5. Protection Class (IP,H-F)Protection Class According to DIN 40050 Norm:
Ersin ERDALI 80
4.LetterFinishing letter depends on request(H,M,S,W)
For Dangerous Places ; H: High voltage device M: Testing against water input demaged when the
moving parts act (exp: rotor) S : Testing against water input demaged when the
moving parts stop (exp: rotor) W: Suitable to use on specified weather condition
and addition protection features
5. Protection Class (IP,H-F)Protection Class According to DIN 40050 Norm:
Ersin ERDALI 81
ISOLATION CLASS OF INSULATOR MATERIALS ACCORDING TO VDE 0530 STANDARD:
� CLASS H ISOLATION :
Allowable maximumtemperature is about180°C�dir. (Operationtemperature is about130°C)
� CLASS F ISOLATION :
Allowable maximumtemperature is about155°C�dir.
5. Protection Class (IP,H-F)
Ersin ERDALI 82
6. 6. TroubleshootingTroubleshooting GuideGuide
Before The Maintenance :
Before any cleaning, lubrication ormaintenance operation, ensure thatthe genarator is stationary anddisconnected from the powersupply
The people in charge of thehandling must always wear workgloves and safety shoes
Do not operate the generator withprotective covers, access covers orterminal box covers removed.
Disable engine starting circuitsbefore carrying out maintenance
Ersin ERDALI 83
Alternator Maintenance :
Lubricating :� Lubricating components should be cleanly.� Using the suitable oil.� Operate the alternator and shooting outthe excess oil.
Ballbearing Lifetime :� For the maintenance-free ball bearingsapproximately 30.000 hours
� For the lubricatable ballbearings approximately40.000 hours
6. 6. TroubleshootingTroubleshooting GuideGuide
Ersin ERDALI 84
Checking The Windings :
Resistance Test� According the alternator manual values; measuring and comparing windings resistanceof the main stator-rotor and excitation stator-rotor.
Insulator Test�Measure main stator-rotor and excitationstator-rotor with the meger (1MOhm).
� Before test remove all connections of theAVR.
� During the test 500 V AC effect the windings.
6. 6. TroubleshootingTroubleshooting GuideGuide
Ersin ERDALI 85
� Study the problem thoroughly before acting.� Refer to the alternator system diagrams.� Check the control unit and all cable connections� Do the easiest and most logical things first.� Find and correct the cause of the problem.
6. 6. TroubleshootingTroubleshooting GuideGuideFollow the suggestions below for troubleshooting :
Ersin ERDALI 86
Troubleshooting - 1 :
� Alternator does not excite ?
Type of Troubleshooting Solving the trouble
Faulty fuse
Low permanent voltage
No permanent voltage
Substitute fuse
Increase speed 15%.
Shock the main rotor bypolarity.
6. 6. TroubleshootingTroubleshooting GuideGuide
Ersin ERDALI 87
� Low voltage at no load ?
Voltage potentiometer is out of balance
Regulator is protected
Faulty windings
Faulty regulator
Set the voltage potentiometer
Check engine speed
Check the windings
Substitute the regulator
6. 6. TroubleshootingTroubleshooting GuideGuide
Troubleshooting - 2 :
Type of Troubleshooting Solving the trouble
Ersin ERDALI 88
� High voltage at no load ?
Voltage potentiometer is out of balance
Faulty regulator
Set the voltage potentiometer
Substitute the regulator
6. 6. TroubleshootingTroubleshooting GuideGuide
Troubleshooting - 3 :
Type of Troubleshooting Solving the trouble
Ersin ERDALI 89
� Normal voltage at no load, than lower voltage at loaded
Regulator is protected
Faulty regulator
Faulty diodes
Current too high, power factorlower than 0.8, speed lower than4% of rated speed.
Substitute regulator
Check diodes
6. 6. TroubleshootingTroubleshooting GuideGuide
Troubleshooting - 4 :
Type of Troubleshooting Solving the trouble
Ersin ERDALI 90
Faulty Regulator Substitute regulator
6. 6. TroubleshootingTroubleshooting GuideGuide
Troubleshooting - 5 :
Type of Troubleshooting Solving the trouble
� Normal voltage at no load, than higher voltage at loaded
Ersin ERDALI 91
� Unstable voltage ?
Unbalance engine speed
Faulty regulator
Stability potantiometer is out of unbalance
Set the engine speed
Substitute regulator
Regulate stability of regulator byacting on �STAB.� potentiometer.
6. 6. TroubleshootingTroubleshooting GuideGuide
Troubleshooting - 6 :
Type of Troubleshooting Solving the trouble
Ersin ERDALI 92
� Abnormal Noises ?
Faulty ballbearings Substitute ballbearings
Check the assembly bolts. Ifit needs, substitute bolts
6. 6. TroubleshootingTroubleshooting GuideGuide
Troubleshooting - 7 :
Type of Troubleshooting Solving the trouble
Unstuck assembly
Ersin ERDALI 93
ALTERNATOR TRAINING FINISHED
QUESTIONS
ANSWERS
THANKS