5 WMEA Nov 2009 Power Trak Plus r2

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Enhanced Power Trak Sync Excit at ion System

Slide 1

Western Mining Electrical Association - November 2009 We Drive Industry

Power Trak Pro-ActionSync Excitation SystemPower Trak Pro-ActionSync Excitation System

Presented by Bill Horvath, TM GE Automation Systems

At Western Mining Electrical Association

San Antonio, Texas

November 2009

Presented by Bill Horvath, TM GE Automation Systems

At Western Mining Electrical Association

San Antonio, Texas

November 2009

TMGE Automation Systems TMGE Automation Systems




Slide 2


Dragline Sync Excitation Enhancements

• What is needed for good draglineoperation?

• Maintaining Dragline Trail CableVoltage

• Sync Motor Basics and Operation

• Sync Field Excitation Evolution & Issues

• Sync Field Excitation SystemPerformance




Slide 3


• Voltage must be held torange of

Plus 10% to -5%• High Side range limit

due to motor voltagestress

• Low side range due tosync torque loss withvoltage drop: pull out!

Good Dragline Operation




Slide 4


Why Use Sync Motors?REACTIVE POWER VOLTAGE CONTROL!

NO SYNCHRONOUS MOTOR WITH SYNCHRONOUS MOTOR

RESULT: L ARGE VOLTAGE SWINGS AT BUS 2 & 3

RESULT: GREATLY REDUCED VOLTAGE SWINGS AT BUS 2 & 3




Slide 5


Challenge:Pit Conditions Changing

• When Draglines are moved to new diggingareas, Z3 [pit distribution impedance] changes.

• Field Excitation Control set up for best voltagecontrol at Bus 3 may have to change to keep Bus3 volts within -5% + 10% motor limits.




Slide 6


Dragline Real & Idealized Power Cycle

Sync Motor Loading

Peak Hoist DC kw+Peak Swing DC kW/ effic./ 2.5 pull out margin

@95% volts

Max Regen 60% xpeak motoring




Slide 7


Sync Motor SizingDC MG Set PEAK POWER CALCS Master Sheet MGPKPOWER-2.xls Rev 12-06/07

This Sheet 8750-Billiton-POWER-1.xlx Rev 12-06/07

Fill in values in Blue - otherS are calculated.

BHP Billiton NUMBER OF SETS: 4Billiton 8750

MOTION Mot Qty Motor Pk Volts P eak Amps Max DC KwKW to Include

in DL Pk KWMOTION Motor

Gen NP

KW

Gen Pk

Volts

Amps at

Pk volts#GENS

PEAK DC

KW

Percent

Contrib

Tot Contrib

kW to MG

Motor @

Peak power

HOIST 8 MD824 660 2610 13781 13781 HOIST MD824 1254 660 2610 2 3445 100% 3445

DRAG 8 MD824X 660 2610 13781 0 DRAG MD824X 1254 660 2610 2 3445 0% 0

SWING 8 MD824 600 2610 12528 12528 SWING MD824 1045 600 2610 2 3132 100% 3132

DC DRIVES

KW TOTAL 26309

DIV BY .95*.95 EFFIC 0.9025 TOTAL DC GEN KW 6577

DRIVES AC TOT KW 29151 GEN EFFIC 0.93

+AUXIL KW 2500 SHAFT KW [TOT/EFF] 7072

DRAGLINE TOT PK KW 31651 SHAFT HP [KW/.746] 9480

DRAGLINE RMS KW 15192

DRAGLINE AVG KW 9495 TQ AVAIL 2.5

AUX LOAD = 2500 KW MIN VOLTS 0.95

AUX PF = 0.8 LAG 3992

AUX KVA = 2500 + J 1875

MIN SYNC N.P. HP

REQU =

[HP/(PK TQ*MIN VOLTS)]

MOTOR SELECTION AND TOTAL DL POWER

MG SYNC MOTOR LOADINGAND MARGIN CALCULATION




Slide 8


After Synchronizing – With DC Field• Rotor follows stator

magnetic wave at syncRPM

• Magnetic Couplingbetween Stator &Rotor:Like an elastic band

Torque “stretches” bandand rotor trails stator byan angle called the

torque angle




Slide 9


Sync Motor ModelFully Running

Effect of DC Field

•Sync Motor KVAR

Exported with strong DCfield [leading pf]

Imported with weakerfield [lagging pf]

•Increases torquecapability [power output]

R1 Xd

MagnetizingCurrent

POWER

SOURCESingle Phase Synch Motor Model

LAM

RAM

Amort.

Ef




Slide 10


Sync Motor Reactive Power• Motors are rated both in

kVA and HP [or kW] and PF

• Typically 1.0 PF or 0.8 leadPF

• Excavator MG sync motors:NNNN HP, 0.8 pf

250% pullout torque at 0.95

volts6-pole, 1200 RPM [1000 RPM

on 50 Hz]

Power kW]

K V A

K V A R

Power factor = Cos




Slide 11


Sync Rotor Power Curve•Curve applies to aparticular level of fieldgenerated volts [Ef ] and

Terminal Volts [V1]•Stronger Ef or changing V1

affects max power

•Power [torque] past 90

deg will result in de-sync




Slide 12


Sync Motors & Torque Production

S N

FLUX LINES FLUX LINES

F L U X

L I N E S

F L UX

L I NE S F

L U X

L I N E

SF

L UX

L I NE S

F L U X

L I N E S

Rotor

Rotation

Torque

angle

N

S

STATOR FIELD

N

S

Motoring Torque

Rotor Trails Stator Wave

S N


F L U X

L I N E S

F L UX

L I NE S F

L U X

L I N E

SF

L UX

L I NE S

F L U X

L I N E S

Rotor

Rotation

Torque

angle

N

S

STATOR FIELD

N

S

Regen Torque

Rotor Leads Stator Wave




Slide 13


Summary

• Sync Motor provides kW to

generators but can independentlygenerate KVAR [reactive power]

• Reactive power flow opposite of kW

helps hold voltage at DL steady.




Slide 14


Sync Motor MG Set 2-3 Hz Natural Frequency•Sync Motors all have a natural

frequency – like a spring and mass•Natural frequency f n of a connected

motor is approximately:

•For Dragline MG sets [sync motorplus DC gens] this natural frequencycalculates to 2-3 Hz

•Increasing field strength “stiffens” the

spring, but does not change thenatural f n.•Impact loading on motor can

“bounce the spring”.

f n 35200RPM

Pr x f WK 2

=

S N


F L U X

L I N E S

F L UX

L I NE S F

L U X

L I N E

SF

L UX

L I NE S

F L U X

L I N E S

Rotor

Rotation

Torque

angle

N

S

STATOR FIELD

N

S

Swing from Motor to Regen Power

Stimulated 2 Hz with Low Damping




Slide 15


Sync Motors 2 Hz Example

S N


F L U X

L I N E S

F L UX

L I NE S F

L U X

L I N E

SF

L UX

L I NE S

F L U X

L I N E S

Rotor

Rotation

Torque

angle

N

S

STATOR FIELD

N

S

Swing from Motor to Regen Power

Stimulated 2 Hz with Low Damping




Slide 16


2 Hz Rotor Power – Where Can It Go?

• Disturbance power flows into power

system, swinging AC volts!• Amortiseur winding provides damping

torque.

POWER SOURCE

One Phase Model




Slide 17


2 Hz MG Set Resonance Effects

• Sudden load impacts shift sync motorpower [torque] angle

• Rotor overshoots, swings back and forth.

• Rotor angle pushes watts and vars in andout of dragline sometimes in huge swings

• Voltage swings can trip off dragline andnearby equipment




Slide 18


Notes & Experience with 2 Hz Problems• All sync MG sets have 2-3 Hz resonance!

• Amortiseur windings of low starting current motors[400-450% vs standard 600%] have low damping

and prone to worse 2 Hz problems.• Weak pit feeder gives low damping – worsens 2Hz.

• Using DC kW as field amps reference has shownto be best in 2 Hz performance and voltage stability

• High forcing [ratio of exciter max volts to sync fieldhot drop] helps.




Slide 19


Example Traces of 2 Hz Phenomenon[before analog regulator modifications]

Thanks to Monte WilkeWestern Energy Co

Coalstrip, MT DL3124

1. Freq = 1/0.467 = 2.14 Hz

2. kW Transducer is notlying! Rotor oscillationsare really causing wildpower swings

Large power swings show upat trail cable as measuredby PTs

Rotor amps follow kWfeedbback with 2 hz




Slide 20


Example Traces of 2 Hz Phenomenon[after regulator modifications]




Slide 21


Sync Motor Excitation Hardware




Slide 22


Sync Excitation Control Hardware Evolution• Rotating Exciters with

Fixed Field - resistor off 120 volt house exciter

Multi-step Contactors & Resistors off 120 volt house exciter

Dedicated 230 volt sync exciter with Saturable Reactor fieldcontrol

• Solid State op-amp & direct analog thyristor exciter

• Digital thyristor exciter with reactive power control infirmware.

• PLC based field excitation reference control• IGBT based exciters




Slide 23


Notes on Voltage “Forcing” on Sync Excitation

• Inductance and resistance of sync DCfield gives natural time constant of 2-3sec

• Min source volts must provide peakamps @ hot voltage drop

• Higher available source volts allowsfaster change of current to desired levelto follow duty cycle, hold excitation

TimeConstant

TypicalL/Rhot =2-

3 sec

L

RSync

MotorDC

Field

DCExcitation

SourceRatings:

* Peak Volts,

* RMS Amps* Peak Amps* Response

Typical Hot-Drop =90-120 volts

Rated Field

Max Field [@ peak kW]

300 V Exc. Volts

600 V Exc. Volts

~4-6 sec

~1 sec >

~0.6 sec

Min Exc Volts =180=120 v x 150%




Slide 24


Sync Motor Excitation Control

Schemes






Slide 26


Sync Reactive Regulating Schemes

A. POWER FACTOR REGULATORSingle PF setting with minimum field clamp.

B. WATT-VAR REGULATORMultiple break slope VAR vs Input KW

C. FIELD CURRENT VS KW [POWER TRAK] REGULATORMultiple break slope Sync Field Amps vs AC kW

D. ENHANCED POWER TRAK REGULATORMultiple break slope Sync Field Amps vs DC kW with ACkW fixed offset

[+] MOTORING KW[-] REGENERATING KW

S Y N C F I E L D

C U R R E N T

C. POWER TRAK

REGULATOR

Rx3i Controller ReferenceShaping

[+] MOTORING KW

K V A R [ - ]

A. POWER FACTOR

REGULATOR

[-] REGENERAT ING KW

[+] MOTORING KW

K V A R [ - ]

B. KW VS KVARREGULATOR

[-] REGENERATIN G KW [+] DC MOTIONPOWER KW

S Y N C F I E L D

C U R R E N T

D. ENHANCED POWER

TRACK REGULATOR


[-] DC MOTIONPOWER KW




Slide 27


Power Factor RegulatorSimplified Representation




Slide 28


Pure “Power-Factor” RegulatorCalculated Performance

Es = 1.075

Z = .06 + j .16

+ P.U. POWER- P.U. POWER

PF=0.936

Q / P = R / X

P F = 0 .9 1

CONSTANT

REGULATED

POWERFACTOR ONLY

CREATES

SYMETRICAL

VOLTAGE

DROP OR RISE!

VOLTAGE DROP VS POWER




Slide 29


Watt-VAR [KVAR vs Kw] RegulatorSimplified Representation




Slide 30


kW vs Field Current [Power-Trak] RegulatorSimplified Representation – Any technology




Slide 31


Sync Field Current vs Kw Regulator [Power-Trak]Advantages vs PF or WATT-VAR Regulators

• Lower Overall Cost

• Easier to understand, easier to adjust• Better voltage regulation from:

Independent regulation of motoring andregen allows lower field amps at light load

As line voltage from utility side drops, syncmotor automatically produces morecompensating kVARs to hold voltage.




Slide 32


Details on TraditionalAC kW Ref Power Trak[with DC-EXX

Implementation]

[+] MOTORINGAC KW

[-] REGENERATINGAC KW

S Y N C

F I E L D

C U R R E N T

TRADITIONAL

POWER TRAK REGULATORSYNC FIELD CURRENT

VS AC DRAGLINE KW


D

PLC Based orDiscreteWATT

TRANSDUCER

SM1SM2

Trail Cable

Voltage

6.6 kv Nom

AUXLoads

Nom 435

Rx3iController

T h yr i t e

T y pi c al

9 Wx

2 0 H

X 1 2 D

3 0 0 A

k W

F e e d

b a c k

[+] KW

I f i e l d

Reference shapingFunction within

Controller

Sync

mot field

Typical DC-EXX Field controlEach Motor

AC Utility Amps and Volts

CT

PT

A

C

B

F

E

F

kWkVar

MotoringPower Flow

kWkVar

RegeneratingPower Flow

Trail

Cable




Slide 33


OVERVIEW:

Traditional

System with

AC kW and or Kvar

Transducer

SignalsG

G

MM

SYNCMOT

MGINERTIA

ROTORANGLE

STATOR

KW Transducer

WATT VAR orPower TrakRegulator

Exciter

Sync field

2 sec timeconstant

[+] MOTORING KW

K V A R

[ - ]

B. KW VS KVAR

REGULATOR

[-] REGENER ATING KW

REF SHAPER

UTILITYPOWER




Slide 34


Traditional Sync

Excitation SystemOperation

G

G

MM

SYNC

MOT

MGINERTIA

ROTORANGLE

STATOR

KW Transducer

WATT VAR or

Power TrakRegulator

Exciter

Sync field

2 sec timeconstant

[+] MOTORIN G KW

K V A R

[ - ]

B. KW VS KVAR

REGULATOR

[-] REGENERATI NG KW

REF SHAPER

UTILITYPOWER

1. Load Change [A Rock]

2. Torque on Motor & Gen

3. Delay from MG inertia

4. Torque angle increase

on sync5. AC Line torque [real]

amps increases

6. Watt Transducercreates kw signal

7. Ref shaper create ref

8. Regulator9. Exciter creates field

volts

10.Field amps increases

11.Torque angle shrinks

1. BIGRock!

2. Torque

4. IncreaseTorque Ang le

7. Ref

Shaper

3. Delay

5. Torque Amps

8.Regulator

6. KWSignal

9. VoltageOutput

10. Field Amps

11. ReduceTorque Angle




Slide 35


Traditional Power Trak System Limitations• Inherent delays in feedback quantities

themselvesAC kw is a response to digging loads after MG

inertiaAC kW changes AFTER need for more excitation

• Transducers are slow• Allows more rotor movement and increases

chance of 2 Hz trouble

• A 2 Hz AC kW component shows up on fieldcurrent reference!




Slide 36


Sync SystemDelays

Rotor Angle

ACPower

Dig Cycle

DCPower

ACVoltage

PitDistrib

Utility

Rotor Angle

ACPower

Dig Cycle

DCPower

ACVoltage

PitDistrib

Utility

APPLY FIELDCORRECTION AFTER ACFEEDBACK

APPLY FIELDCORRECTION ASSOON AS DC KW

CHANGES




Slide 37


G

G

MM

SYNC

MOT

MGINERTIA

ROTORANGLE

STATOR

KW Transducer

WATT VAR or

Power TrakRegulator

Exciter

Sync field

2 sec timeconstant

[+] MOTORIN G KW

K V A R

[ - ]

B. KW VS KVAR

REGULATOR

[-] REGENERATI NG KW

REF SHAPER

UTILITYPOWER

1. BIGRock!

2. Torque

4. IncreaseTorque Ang le

7. Ref

Shaper

3. Delay

5. Torque Amps

8.Regulator

6. KW

Signal

9. VoltageOutput

10. Field Amps

11. ReduceTorque Angle

Improving the“traditional”

system• AC kW shows up

too late!•Inertia slows the

feedback more!

•Torque angle

overshoots•kW transducers

are slow




Slide 38


Details on DC kW Ref Pro-Action Power Trak

[with DC-EXXImplementation]

[+] DC MOTIONPOWER KW

S Y N C F I E L D

C U R R E N T

ENHANCED POWERTRACK REGULATOR



SM1SM2

Trail Cable

Voltage

6.6 kv Nom

AUXLoads

Rx3iController

T h yr i t e

T y pi c al

9 W

x

2 0 H

X 1 2 D

3 0 0 A

Motion kW

Summation

[+]KW

I f i e l d

Profibus

Syncmotfield

Field Control Sameas SM1

Typical DC-EXX Field controlEach Motor

Field CurrentReference to

each exciter

A

C

D

F

E

F

kWkVar

MotoringPower Flow

kWkVar

RegeneratingPower Flow

Trail

Cable

Utility Source

HoistDC Arm Volts

& Amps

Drag/PropelDC Arm

Volts & Amps

Swing DC ArmVolts & Amps

DC PowerSummation

CT

Aux Watt &Var Trans[option]

AuxKW Bias

PT

Profibus

B

Reference

shaping

Function

within

Controller




Slide 39


DC V &AmpsIsol

SWING

DC V &AmpsIsol

DRAG

DC V &AmpsIsol

HOIST

Power TrakField CurrentReference

Exciter

Sync field

2 sec timeconstant

RX3i

Prrocessor [<10 ms scan]

PLC Analog I-O& DC Power Calc &

DC KW Summer

[+] DC MOT IONPOWER KW

S Y N C

F I E L D

C U R R E N T

ENHANCED POWER

TRACK REGULATOR

Rx3i Controller Reference

Shaping


OVERVIEW:

Power Trak

Excitation

System with DCKw Reference –

ProAction

G

M M

100 mVshunt

G

SYNCMOT

MG

INERTIA

ROTOR

ANGLE

STATOR

UTILITY

POWER




Slide 40


DC V &AmpsIsol

SWING

DC V &AmpsIsol

DRAG

DC V &AmpsIsol

HOIST

Power TrakField CurrentReference

Exciter

Sync field

2 sec timeconstant

RX3i

Prrocessor [<10 ms scan]

PLC Analog I-O& DC Power Calc &

DC KW Summer

[+] DC MOT IONPOWER KW

S Y N C

F I E L D

C U R R E N T

ENHANCED POWER

TRACK REGULATOR

Rx3i Controller Reference

Shaping


Power Trak

ProAction SystemOperation

1. Load Change [A Rock!]

2. Torque on Motor & Gen

3. Armature amps & voltsfeedback

4. PLC Calcs & Sums allDC kW

5. Ref shaper creates fieldamps reference

6. Exciter applies fieldvolts

7. Field amps increases8. Torque angle minimized

G

M M

100 mVshunt

G

SYNCMOT

MG

INERTIA

ROTOR

ANGLE

STATOR

UTILITY

POWER

1. BIGRock!

2. Torque

8. Torque Angle

5. Ref Shaper

7. Field Amps

3. Arm V& Amps

4. PLCCalc &Sum

6. FieldVolts




Slide 41


Summary of Benefits fromChanges

• Take field strength action based onreal digging load – pro-actively

• Eliminate delays frominertia, ACkW feedback.

• Reduce voltage swings atAC feed

or upstream.




Slide 42


Example Performance Traces




Slide 43


Case 1: Watt-Var SystemPartial Step of Replacing AC Kw

Reference with Total DC kW




Slide 44


Case 1: Watt-Var System on 4 Set Machine

“BEFORE”

• Watt-Var regulator• Existing DL with 4

sets, two exciters• Two different Sync

motors• 2nd exciter slave to first• Two Hz Swings

HUGE: even causedtrips

• Tune-ups did not fixproblem

Thyristor Non-Reversing

Plugging Exciter

435 VAC3-ph

T1

300 - 550VDC


Plugging Exciter

T2

300 - 550VDC

Master

Slave

SyncMotor

#1 & #2

Fields

Sync

Motor#3 & #4Fields

435 VAC3-ph

[+]MOTORING KW

K V A R

[ - ]

B. KW VS KVARREGULATOR

[-]REGENERATING KW

Field CurrFollower Ref

AC Kw

AC KVAr




Slide 45


•Red trace = Totalmachine kW

•Two Hz ringing onAC kW is about 8MW peak to peak!

•Blue Trace = TotalDC kW


“BEFORE”

DRE03 June 2008




Slide 46


Case 1: Watt-Var System on4 Set Machine

“ AFTER”

• 2nd exciter still slave tofirst

• Configuration set upwith DC Motion kWreplacing AC kW

• Rest of Watt-Var

regulator stayed thesame

Thyristor Non-

ReversingPlugging Exciter

435 VAC3-ph

T1

300 - 550VDC


Plugging Exciter

T2

300 - 550VDC

Master

Slave

SyncMotor

#1 & #2

Fields

Sync

Motor#3 & #4Fields

435 VAC3-ph

[+]MOTOR INGKW

K V A

R [ - ]

B. KW VS KVAR

REGULATOR

[-]REGENERATING KW

Field CurrFollower Ref

AC KVAr

DC V &

AmpsIsol

SWING

DC V &Amps

Isol

DRAG

DC V &

AmpsIsol

HOIST

PLC Analog I -O

& DC Power Calc &DC KW Summer




Slide 47


Case 1: Watt-Var System on 4 Set Machine“ AFTER” – DC Power Reference Components

AC Vol ts22.4 kv +/- 500 v

DragDC kW

SwingDC kW

HoistDC kW

Total

DC kW

•DC kW reference issum of each motionDC power

•Heavy double-traces are MG ACkw with slight 2-Hzringing

•DL trail cable volts+/- 2.5% - good!




Slide 48



“ AFTER”

•Red trace = Totalmachine kW

•Blue Trace = TotalDC Motion kW

•Green Trace = TotalMachine KVAR

•Two Hz ringing onkW and KVAR isessentially gone.

DRE03 June 2008




Slide 49


Case 2: Power Trak Plus Pro-action

SystemReplacing AC Kw Reference

with Total DC kW vsSync Field Current Function




Slide 50


Hoist Amps

HoistVolts

Drag Amps

DragVolts

Swing Amps

Swing

Volts

ACWatts

ACVARS

•Traces are of loopamps and volts, all 3motions

•Volts and amps aremultiplied and added togive DC Motion kW

•Total Machine AC kWand KVAR shown

•AC kW used for field

reference•Two Hz ringing on both

kW and KVAR

Power Trak Pro Action Power Traces




Slide 51


DC Machine kW vs Sync Field Amps ReferenceTotalDC kW

SyncField Ref

3 5 5 0

200

100

7 1 0 0

- 3 5 0 0

8 8 7 5

F i e l d A m p s R e f

Total DC kW [+]Total DC kW [-]




Slide 52


Actual Field Current Feedbacks Two Field Sync System




Slide 53


Effect of Changing From AC to DC kW Sync Reference Input

AC Watts[Not used as ref!]

DC TotalWatts Ref

DC Field AC kVAR

•Top trace is DC MotionkW – sync field ref

•Total Machine AC kWshows 2-Hz ringing

•Switching to DC kW forPower Trak Ref:

Two Hz ringing on KVARcompletely gone

•AC line volts at DL morestable – pit feed is 2.5:1

reactive•AC line volts at utility

muchmore stable – pitfeed is highly [6:1] reactive




Slide 54


Example Calc of Voltage Swing

• 30% kw swing • 30% kVAR swing

•Power delivery Equation:Es2 = Er2 +I2{R2 + X2}+ 2{PR + QX}

LOAD

XErEs R

I, P, Q .

“ TYPICAL” DL FEED Zpu = .06 + j0.16




Slide 55


DifferentSystem: Ehsham#1

AC DLWatts[Red]

DC TotalWatts Ref [Gray]

•Top [grey] trace is DCMotion kW

•AC Aux Power [fans, etc]

is added to DC kW asoffset

•DC kW + Offset is inputto sync field function gen

•Total Machine AC kW[red] trace – NO 2 Hzringing




Slide 56


DC kW and Sync Field Ref For Ehsham#1•Multiple DL Cycles

•Grey trace is DC Motion kW,used as sync field reference

•Red trace – total DL kVAR

•kVAR compensation followsfunction in PLC regulator.

•Min field for low kW andregen modes

DC TotalWatts Ref

AC kVAR




Slide 57


Total System Performance – Ehsham#1

•Multiple DL Cycles

•DC Motion kW with ACaux offset used as sync

field reference

•AC kW shows NOstimulation of MG 2 Hzoscillation

•Line volts held to +/-300 volts out of 6600

volts: good!

AC kW

DC kW[w AC Offset]

Sync FieldRef

AC Vol tsIncoming




Slide 58


Power Trak ProAction Regulator Take field strength action based on

real digging load – pro-actively

Sum of DC Motion kw used asreference

Reduces stimulation of 2 – 3 HzSync-MG oscillations

More accurate VAR control

Eliminate kW and Var transducer

Optional long term [10 minute T.C.]integration of actual variations insystem – to compensate forchanges

Faster response to match sync fieldstrength to digging needs

Eliminate delays from inertia, AC kWfeedback.

Better operation & less impact onmine and utility

Reduce voltage swings at AC feed orupstream

Reduce parts count

Adapt to changing utility or pitconfiguration




Slide 59

W Mi i El i l A i i N b 2009 W D i I d

Thanks!

Office Location:

TM GE Automation Systems, LLC

1325 Electric Road Roanoke, VA 24018 [Office]2060 Cook Drive Salem VA, 24153 [Mailing]

USA

TEL: +1-540-283-2000; FAX: +1-540-3283-2005www.tmeicge.com

Documents

5 WMEA Nov 2009 Power Trak Plus r2