SlideShare ist ein Scribd-Unternehmen logo
1 von 24
Downloaden Sie, um offline zu lesen
Estimation of Induction Motor 
Operating Power Factor From 
Measured Current and 
Manufacturer Data
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
index 
Sl 
No 
Tittle Page 
No 
1 Introduction 02 
2 Background Information 04 
3 Current –Only, Pf Estimation 06 
4 Power Factor: From Voltage, Current ZC 11 
5 Power Factor: From Instantaneous Power 14 
6 Discussion Of Results 16 
7 Conclusion 20 
8 References 21 
1
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
introduction 
“ THREE-PHASE induction motors (IM) are industrial work-horses, 
responsible for consumption of 40–50% of generated 
electrical power. ” 
2
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
 Recently there has been a lot of focus on IM 
protection at LV, &MV levels. 
 These protection devices typically monitor the 
motor current and/or voltage to provide the motor 
protection functionalities 
 One of the interesting parameters to monitor is the 
operating power factor (PF) 
 Traditionally, to monitor the operating PF of the IM, 
one would require both the voltage and the current 
A low cost method of determining the operating PF 
of the IM using only the measured current and the 
manufacturer data is developed. 
3
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
BACKGROUND INFORMATION 
IM equivalent circuit. 
Leakage reactance 
I1 = Im+I1 ’ Load 
v1 
I1 
r1 X1 
rC Xm 
I1’ 
X2’ 
r2’ 
s 
component 
Exciting 
component 
Im 
core-loss 
resistance 
magnetizing 
reactance 
stator 
Rotor 
4
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
Power Factor and Motor Load 
 휽ퟎ in the range 75 –85 
ie, stator PF at no load may 
be as low as 0.1–0.3. 
 Typically, stator PF of 
about 0.8–0.9 at 80–100% of 
the full-load 
 I1’ N1= I2’ N2 
5
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
CURRENT –ONLY, PF ESTIMATION 
 Total input electrical apparent power , 푷 = ퟑ푽푰 
 Active power, for supplying the load ,푷 = ퟑ푽푰 cos ∅ 
 PF = 
푷 
푷 
= cos ∅ Eqn 1 
 I= 푰풂풄풕풊풗풆 
ퟐ + 푰풓풆풂풄풕풊풗풆 
ퟐ 
 푰풂풄풕풊풗풆 = I cos ∅ , 푰풓풆풂풄풕풊풗풆= I sin ∅ 
 푰풓풆풂풄풕풊풗풆=I sin cos−ퟏ(푷푭) Eqn 2 
PF = 푐표푠 ∅ = 1 − 푠푖푛∅2 = 1 − ( 
퐼푟푒푎푐푡푖푣푒 
퐼 
)2 Eqn 3 
6
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
 푰풓풆풂풄풕풊풗풆 remains constant, it can be estimated from 
nameplate data using 푰풓풆풂풄풕풊풗풆= I sin cos−ퟏ(푷푭) 
 At no-load condition, there is no active current flow. 
So, at no-load, I= 푰풓풆풂풄풕풊풗풆 PF = 0 ( 
퐼PF= 1 − ( 
푟푒푎푐푡푖푣푒 
퐼 
)2 ) 
 As motor load increases the PF will increase toward 
unity. 
Motor 
load 
increases 
Total 
motor I 
increase 
푰풓풆풂풄풕풊풗풆 
remains 
constant 
( 
푰풓풆풂풄풕풊풗풆 
푰 
)ퟐ 
Decreases 
 Physically, at no-load, there is not much mechanical 
resistance, so the whole circuit is mostly inductive due to 
the stator coils, causing low PF. 
7
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
Basic Algorithm 
 Estimate the 푰풓풆풂풄풕풊풗풆 from the nominal PF out of 
the nameplate data. ( 푰풓풆풂풄풕풊풗풆=I sin cos−ퟏ(푷푭)) 
 Estimate the operating PF from measured motor 
current & constant 푰풓풆풂풄풕풊풗풆 
“ It would not require synchronized voltage and 
current measurement like in the displacement PF 
measurement principle.” 
8
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
experimental setup 
Load 
supply 
Motor 
supply 
ABB 
Lv drive 
IM 3 ph 
Load 
Motor 
(7.5kw) 
Test Motor 
(2.2 kw) 
two pole 
pairs IM, 
M2AA LA4 
Motor 
current 
measureme 
nt 
Main supply (50 Hz) 
IM 3 ph 
9
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
NAME PLATE RATING OF THE 
TEST MOTOR TYPE ABB M2AALA4. 
NOMINAL VOLTAGE 4 00V 
NOMINAL CURRENT 4.9A 
RATED POWER 2.2KW 
RATED PF 0.81 
RATED SPEED 1430 RPM 
푰풓풆풂풄풕풊풗풆=I sin cos−ퟏ(푷푭) 
= 4.9* Sin (cos−1 0.81) 
=2.87 
MEASURED I,CALCULATED PF 
FROM 
CURRENT-ONLY METHOD AT 
DIFFERENT LOAD 
Measured 
CURRENT 
I(A) 
I/푰풏풐풎풊풏풂풍 (%) PF 
3.01 61.43 .30 
3.23 65.92 .46 
4.37 89.18 .75 
5.21 106.33 .83 
6.21 126.73 .89 
PF= 1 − ( 
퐼푟푒푎푐푡푖푣푒 
퐼 
)2= 
2.87 
3.01 
1 − ( 
)2 = 0.3 
10
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
Power Factor: From Voltage, Current ZC 
Basic Algorithm 
 Synchronized measurement of the supply voltage and 
the motor current are done. 
 Displacements in the ZC timings between the voltage 
(taken as reference) and the current signals are 
estimated. 
 Estimate the PF using the equation ±x ms : Deviation between the current 
ZC w.r.t. the voltage ZC, 
 풇ퟎ ∶ 퐒upply frequency. 
PF=풄풐풔( 
풙 
( 
ퟏ 
풇ퟎ 
) 
X ퟑퟔퟎퟎ) 
 The current ZC deviation is positive or negative w.r.t. 
The voltage would decide whether the PF is lagging 
or leading. 
11
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
experimental setup 
Load 
supply 
Motor 
supply 
ABB 
Lv drive 
IM 3 ph 
Load 
Motor 
(7.5kw) 
Tektronix Voltage probe 
Current hall-sensor probe 
Test Motor 
(2.2 kw) 
two pole pairs IM, 
M2AA LA4 
Main supply (50 Hz) 
oscilloscope 
Agilent 
IM 3 ph 
12
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
PF MEASUREMENT USING 
DISPLACEMENT IN THE ZC OF THE 
SYNCHRONIZED SUPPLY VOLTAGE 
AND MOTOR CURRENT AT 66% 
CURRENT LOAD. 
 ±x ms : 3.4 ms ,풇ퟎ = 
ퟓퟎ 
 Pf =풄풐풔( 
풙 
( 
ퟏ 
풇ퟎ 
) 
X ퟑퟔퟎퟎ) 
=cos( 
3.4 
20 
푿 ퟑퟔퟎퟎ) = 
0.48 
RMS CURRENT,TIME DEVIATION 
BETWEEN ZC OF VOLTAGE 
&CURRENT, PF FROM 
DISPLACEMENT METHOD AT 
DIFFERENT LOAD 
RMS 
current 
I(A) 
ZC time 
difference 
(ms) 
PF 
2.97 4.6 0.12 
3.00 3.4 0.48 
3.54 2.8 0.64 
4.24 2.1 0.79 
5.23 1.6 0.87 
13
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
Power Factor: From Instantaneous Power 
Basic Algorithm 
 Estimate instantaneous power per phase (i.e., point-by- 
point multiplication of the two waveforms) from 
the synchronized supply voltage and the motor 
current 
Average power (푃 ) per phase from the 
measurement in the scope. 
Estimate the PF using the equation : PF = 
푃 
푉퐼 
14
Power factor measurement using 
instantaneous power from the measured 
synchronized supply voltage and the 
motor current at 66% current load. 
푃 =328.525 V=230 I=3 
PF = 
푃 
푉퐼 
= 
328.525 
230 푋 3 
= 0.476 
RMS CURRENT,RMS VOLTAGE , 
INSTANTANEOUS POWER ,POWER 
FACTOR AT DIFFERENT LOAD 
RMS 
current 
(A) 
RMS 
voltage 
(v) 
Instantaneou 
s power(w) 
PF 
2.97 230 72.86 0.1 
1 
3.00 230 328.53 0.4 
8 
3.54 230 547.48 0.6 
7 
4.24 230 774.67 0.7 
9 
5.23 230 1014.32 0.8 
4 
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
15
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
DISCUSSION OF RESULTS 
METHOD I(A) PF I(A) PF 
From Measured Current 3.00 0.221 4.24 0.71 
From Voltage, Current ZC 3.00 0.48 4.24 0.79 
From Instantaneous 
3.00 0.48 4.24 0.79 
Power 
“The PF estimation error using the current-only method is 
about +0.04 , except at the no-load condition, where it is 
about−0.18 . This could be because, the sensitivity of the 
motor current measurement module might not be very perfect 
at no-load condition.” 
16
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
 The proposed method relies on the fact that the 
inductance of the total circuit remains constant. 
 This rule might be violated if the motor is supplied via a 
variable speed drive. 
 Most modern drive systems usually measure both voltage 
and current and can provide PF measurement . Hence, no 
need for cheaper calculation of PF. 
 it is assumed that manufacturers comply with the 
relevant IM manufacturing standards, providing rated 
values with acceptable accuracy. 
 Estimation of IM operating PF could be used for PF 
compensation 
17
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
 Under no-load condition, the referred reactance of the 
rotor 
X2’ would be absent. 
 The no-load current would comprise of the magnetizing 
current only. ie the no-load current would not be a good 
representative of the total reactive current 
 So, the reactive current estimated from the rated 
condition, would not miss any inductive elements. 
 For bigger IMs with low I(no−load)/I(rated) ratio, the 
assumption to use I reactive = constant for light loads 
might lead to high errors in the PF estimation. 
 Higher power machines usually come with MV or LV drives 
already provided with the PF computation. 
18
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
Measured current (A) 
Underload protection using motor current & power factor 
Measured current (A) 
푁표푚푖푛푎푙 푐푢푟푟푒푛푡 (퐴) 
Power factor 
Measured current (A) 
푁표푚푖푛푎푙 푐푢푟푟푒푛푡 (퐴) 
 At low loads the nonlinear curve of the PF provides better 
resolution 
 It challenging to accurately measure the low current change 
from small load change at low loading. 
19
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
CONCLUSION 
 Low cost method of determining the operating PF 
of the IM using only the measured current and the 
manufacturer data typically available from the 
nameplate and/or datasheet. 
 This would provide a cheaper solution to under 
load protection, e.g., in pump applications, using 
the operating PF, without requiring the voltage 
sensors. 
 Operational PF can also be used for PF 
compensation to improve the power quality. 
20
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
REFERENCE 
 P.S.Bimbhra, electrical machinery. New delhi, india: 
khanna publishers,, 
 “Identification of induction motor equivalent circuit 
parameters 
using the single-phase test,” IEEE trans. Energy 
convers. 
 Abb. (2009). Manual for low voltage motor. 
Http://www.Abb.Com/motors. 
 Abb. (2010). LV drives, model ACS800. 
Www.Abb.Com/drives 
 D. Sharon, “power factor definitions and power 
transfer quality in no sinusoidal situations,”ieee trans. 
Instrum. 
 “Power-factor compensation of electrical circuits,” 
IEEE control syst. 
21
Thank you! 
22
Estimation of IM Operating PF From Measured Current and Manufacturer Data 
ANY 
QUESTION 
S? 
23

Weitere ähnliche Inhalte

Was ist angesagt?

Automatic power factor correction unit
Automatic power factor correction unitAutomatic power factor correction unit
Automatic power factor correction unitBiswajit Pratihari
 
Reactive Power : Problems and Solutions
Reactive Power : Problems and SolutionsReactive Power : Problems and Solutions
Reactive Power : Problems and SolutionsAbhinav Dubey
 
Power factor
Power factorPower factor
Power factorwkugubre
 
Benifits of power factor improvement for industry
Benifits of power factor improvement for industryBenifits of power factor improvement for industry
Benifits of power factor improvement for industryGovinda Neupane
 
Automatic Power Factor Corrector
Automatic Power Factor CorrectorAutomatic Power Factor Corrector
Automatic Power Factor CorrectorSelf-employed
 
Compensation of harmonic currents utilizing AHC by kingsprime
Compensation of harmonic currents utilizing AHC by kingsprimeCompensation of harmonic currents utilizing AHC by kingsprime
Compensation of harmonic currents utilizing AHC by kingsprimeKalu Kingsley Ekperebuike
 
automatic power factor controller
automatic power factor controllerautomatic power factor controller
automatic power factor controllersingh1515
 
Reactive power compensation
Reactive power compensationReactive power compensation
Reactive power compensationkhaliq ahmed
 
Reactivepowercompensation 140401183847-phpapp01 (6)
Reactivepowercompensation 140401183847-phpapp01 (6)Reactivepowercompensation 140401183847-phpapp01 (6)
Reactivepowercompensation 140401183847-phpapp01 (6)REVANTH CHINTU
 
Synchronous condensers
Synchronous condensersSynchronous condensers
Synchronous condensersujvnl
 
Power Factor : Basics and Benefits of Improvement
Power Factor : Basics and  Benefits of ImprovementPower Factor : Basics and  Benefits of Improvement
Power Factor : Basics and Benefits of ImprovementBijadhar Pandey
 
Automatic power factor correction
Automatic power factor correctionAutomatic power factor correction
Automatic power factor correctionVIKAS KUMAR MANJHI
 
Power factor introduction and its correction final
Power factor introduction and its correction final Power factor introduction and its correction final
Power factor introduction and its correction final manpreetsingh1076
 
Automatic power factor controller by microcontroller
Automatic power factor controller by microcontrollerAutomatic power factor controller by microcontroller
Automatic power factor controller by microcontrollerSanket Shitole
 

Was ist angesagt? (20)

Automatic power factor correction unit
Automatic power factor correction unitAutomatic power factor correction unit
Automatic power factor correction unit
 
PFC - Ducati ANIE 2009
PFC - Ducati ANIE 2009PFC - Ducati ANIE 2009
PFC - Ducati ANIE 2009
 
Power factor improvement
Power factor improvement Power factor improvement
Power factor improvement
 
Power factor
Power factorPower factor
Power factor
 
Reactive Power : Problems and Solutions
Reactive Power : Problems and SolutionsReactive Power : Problems and Solutions
Reactive Power : Problems and Solutions
 
Power factor
Power factorPower factor
Power factor
 
Benifits of power factor improvement for industry
Benifits of power factor improvement for industryBenifits of power factor improvement for industry
Benifits of power factor improvement for industry
 
Automatic Power Factor Corrector
Automatic Power Factor CorrectorAutomatic Power Factor Corrector
Automatic Power Factor Corrector
 
Power factor
Power factorPower factor
Power factor
 
Compensation of harmonic currents utilizing AHC by kingsprime
Compensation of harmonic currents utilizing AHC by kingsprimeCompensation of harmonic currents utilizing AHC by kingsprime
Compensation of harmonic currents utilizing AHC by kingsprime
 
Mohsin rana
Mohsin ranaMohsin rana
Mohsin rana
 
Power Factors
Power FactorsPower Factors
Power Factors
 
automatic power factor controller
automatic power factor controllerautomatic power factor controller
automatic power factor controller
 
Reactive power compensation
Reactive power compensationReactive power compensation
Reactive power compensation
 
Reactivepowercompensation 140401183847-phpapp01 (6)
Reactivepowercompensation 140401183847-phpapp01 (6)Reactivepowercompensation 140401183847-phpapp01 (6)
Reactivepowercompensation 140401183847-phpapp01 (6)
 
Synchronous condensers
Synchronous condensersSynchronous condensers
Synchronous condensers
 
Power Factor : Basics and Benefits of Improvement
Power Factor : Basics and  Benefits of ImprovementPower Factor : Basics and  Benefits of Improvement
Power Factor : Basics and Benefits of Improvement
 
Automatic power factor correction
Automatic power factor correctionAutomatic power factor correction
Automatic power factor correction
 
Power factor introduction and its correction final
Power factor introduction and its correction final Power factor introduction and its correction final
Power factor introduction and its correction final
 
Automatic power factor controller by microcontroller
Automatic power factor controller by microcontrollerAutomatic power factor controller by microcontroller
Automatic power factor controller by microcontroller
 

Andere mochten auch

UNDERGROUND HIGH POWER TRANSMISSION LINES
UNDERGROUND HIGH POWER TRANSMISSION LINESUNDERGROUND HIGH POWER TRANSMISSION LINES
UNDERGROUND HIGH POWER TRANSMISSION LINESVISHNU ARAVIND
 
Micro stepping mode for stepper motor
Micro stepping mode for stepper motorMicro stepping mode for stepper motor
Micro stepping mode for stepper motorSwathi Venugopal
 
Three Phase Ac Winding Calculation
Three Phase Ac Winding CalculationThree Phase Ac Winding Calculation
Three Phase Ac Winding Calculationzlatkodo
 
Power Generation From Waste
Power Generation From WastePower Generation From Waste
Power Generation From WasteManzoor Yetoo
 
Energy storage technologies
Energy storage technologiesEnergy storage technologies
Energy storage technologiessrikanth reddy
 
Energy Storage System
Energy Storage SystemEnergy Storage System
Energy Storage SystemSAMSUNG SDI
 
Latest Seminar Topics for Engineering,MCA,MSc Students
Latest Seminar Topics for Engineering,MCA,MSc StudentsLatest Seminar Topics for Engineering,MCA,MSc Students
Latest Seminar Topics for Engineering,MCA,MSc StudentsArun Kumar
 
Feniks Waste To Energy plant
Feniks Waste To Energy plantFeniks Waste To Energy plant
Feniks Waste To Energy plantfeniks_usa
 
State of the Word 2011
State of the Word 2011State of the Word 2011
State of the Word 2011photomatt
 

Andere mochten auch (18)

Circuitbreaker
Circuitbreaker Circuitbreaker
Circuitbreaker
 
UNDERGROUND HIGH POWER TRANSMISSION LINES
UNDERGROUND HIGH POWER TRANSMISSION LINESUNDERGROUND HIGH POWER TRANSMISSION LINES
UNDERGROUND HIGH POWER TRANSMISSION LINES
 
Micro stepping mode for stepper motor
Micro stepping mode for stepper motorMicro stepping mode for stepper motor
Micro stepping mode for stepper motor
 
Ac motor winding
Ac motor windingAc motor winding
Ac motor winding
 
armature Winding
armature Windingarmature Winding
armature Winding
 
Three Phase Ac Winding Calculation
Three Phase Ac Winding CalculationThree Phase Ac Winding Calculation
Three Phase Ac Winding Calculation
 
Power Generation From Waste
Power Generation From WastePower Generation From Waste
Power Generation From Waste
 
Waste to Energy
Waste to EnergyWaste to Energy
Waste to Energy
 
Energy storage technologies
Energy storage technologiesEnergy storage technologies
Energy storage technologies
 
Energy Storage System
Energy Storage SystemEnergy Storage System
Energy Storage System
 
Abhishek seminar
Abhishek seminarAbhishek seminar
Abhishek seminar
 
WASTE TO ENERGY
WASTE TO ENERGYWASTE TO ENERGY
WASTE TO ENERGY
 
Armature windings
Armature windingsArmature windings
Armature windings
 
Latest Seminar Topics for Engineering,MCA,MSc Students
Latest Seminar Topics for Engineering,MCA,MSc StudentsLatest Seminar Topics for Engineering,MCA,MSc Students
Latest Seminar Topics for Engineering,MCA,MSc Students
 
Power factor improvement
Power factor improvementPower factor improvement
Power factor improvement
 
Feniks Waste To Energy plant
Feniks Waste To Energy plantFeniks Waste To Energy plant
Feniks Waste To Energy plant
 
State of the Word 2011
State of the Word 2011State of the Word 2011
State of the Word 2011
 
Build Features, Not Apps
Build Features, Not AppsBuild Features, Not Apps
Build Features, Not Apps
 

Ähnlich wie Estimation of induction motor operating power factor.

4.5 assessment of motors n
4.5 assessment of  motors n4.5 assessment of  motors n
4.5 assessment of motors npriya3757
 
LTspiceのDCモーターシミュレーション事例
LTspiceのDCモーターシミュレーション事例LTspiceのDCモーターシミュレーション事例
LTspiceのDCモーターシミュレーション事例Tsuyoshi Horigome
 
Catalog biến tần trung thế Fuji Electric
Catalog biến tần trung thế Fuji ElectricCatalog biến tần trung thế Fuji Electric
Catalog biến tần trung thế Fuji ElectricCTY TNHH HẠO PHƯƠNG
 
PARAMETER IDENTIFICATION AND MODELLING OF SEPARATELY EXCITED DC MOTOR
PARAMETER IDENTIFICATION AND MODELLING OF SEPARATELY EXCITED DC MOTOR PARAMETER IDENTIFICATION AND MODELLING OF SEPARATELY EXCITED DC MOTOR
PARAMETER IDENTIFICATION AND MODELLING OF SEPARATELY EXCITED DC MOTOR ijiert bestjournal
 
Motor Current Signature Analysis R K Gupta
Motor Current Signature Analysis R K GuptaMotor Current Signature Analysis R K Gupta
Motor Current Signature Analysis R K GuptaRajuGupta88
 
IRJET- Comparative Study of Sensor and Sensor Less Control of Three Phase...
IRJET-  	  Comparative Study of Sensor and Sensor Less Control of Three Phase...IRJET-  	  Comparative Study of Sensor and Sensor Less Control of Three Phase...
IRJET- Comparative Study of Sensor and Sensor Less Control of Three Phase...IRJET Journal
 
Comparison Analysis of Zeta PFC Converter to Improve Power Quality Improvemen...
Comparison Analysis of Zeta PFC Converter to Improve Power Quality Improvemen...Comparison Analysis of Zeta PFC Converter to Improve Power Quality Improvemen...
Comparison Analysis of Zeta PFC Converter to Improve Power Quality Improvemen...IOSRJEEE
 
Design and Implementation of speed control for 3 phase induction motor using ...
Design and Implementation of speed control for 3 phase induction motor using ...Design and Implementation of speed control for 3 phase induction motor using ...
Design and Implementation of speed control for 3 phase induction motor using ...IRJET Journal
 
Neural Network Based Voltage and Frequency Controller for standalone Wind Pow...
Neural Network Based Voltage and Frequency Controller for standalone Wind Pow...Neural Network Based Voltage and Frequency Controller for standalone Wind Pow...
Neural Network Based Voltage and Frequency Controller for standalone Wind Pow...ijsrd.com
 
DC MOTOR SPEED CONTROL USING ON-OFF CONTROLLER BY PIC16F877A MICROCONTROLLER
DC MOTOR SPEED CONTROL USING ON-OFF CONTROLLER BY  PIC16F877A MICROCONTROLLERDC MOTOR SPEED CONTROL USING ON-OFF CONTROLLER BY  PIC16F877A MICROCONTROLLER
DC MOTOR SPEED CONTROL USING ON-OFF CONTROLLER BY PIC16F877A MICROCONTROLLERTridib Bose
 
Power Factor Correction of Three phase PWM AC Chopper Fed Induction Motor Usi...
Power Factor Correction of Three phase PWM AC Chopper Fed Induction Motor Usi...Power Factor Correction of Three phase PWM AC Chopper Fed Induction Motor Usi...
Power Factor Correction of Three phase PWM AC Chopper Fed Induction Motor Usi...IRJET Journal
 
Identifying Three Phase Induction Motor Equivalent Circuit Parameters from Na...
Identifying Three Phase Induction Motor Equivalent Circuit Parameters from Na...Identifying Three Phase Induction Motor Equivalent Circuit Parameters from Na...
Identifying Three Phase Induction Motor Equivalent Circuit Parameters from Na...ijtsrd
 
Matlab Based Analysis of 3-Ø Self-Excited Induction Generator with Nonlinear ...
Matlab Based Analysis of 3-Ø Self-Excited Induction Generator with Nonlinear ...Matlab Based Analysis of 3-Ø Self-Excited Induction Generator with Nonlinear ...
Matlab Based Analysis of 3-Ø Self-Excited Induction Generator with Nonlinear ...IOSR Journals
 
Simulation And Hardware Analysis Of Three Phase PWM Rectifier With Power Fact...
Simulation And Hardware Analysis Of Three Phase PWM Rectifier With Power Fact...Simulation And Hardware Analysis Of Three Phase PWM Rectifier With Power Fact...
Simulation And Hardware Analysis Of Three Phase PWM Rectifier With Power Fact...IOSR Journals
 
Increase productivity and absorption of reactive power for power station with...
Increase productivity and absorption of reactive power for power station with...Increase productivity and absorption of reactive power for power station with...
Increase productivity and absorption of reactive power for power station with...IJITCA Journal
 
Source current harmonic mitigation of distorted voltage source by using shunt...
Source current harmonic mitigation of distorted voltage source by using shunt...Source current harmonic mitigation of distorted voltage source by using shunt...
Source current harmonic mitigation of distorted voltage source by using shunt...IJECEIAES
 
Control of Switched Reluctance Generator in Wind Energy System
Control of Switched Reluctance Generator in Wind Energy SystemControl of Switched Reluctance Generator in Wind Energy System
Control of Switched Reluctance Generator in Wind Energy SystemNereus Fernandes
 
Iaetsd energy management of induction motor
Iaetsd energy management of induction motorIaetsd energy management of induction motor
Iaetsd energy management of induction motorIaetsd Iaetsd
 

Ähnlich wie Estimation of induction motor operating power factor. (20)

4.5 assessment of motors n
4.5 assessment of  motors n4.5 assessment of  motors n
4.5 assessment of motors n
 
LTspiceのDCモーターシミュレーション事例
LTspiceのDCモーターシミュレーション事例LTspiceのDCモーターシミュレーション事例
LTspiceのDCモーターシミュレーション事例
 
Catalog biến tần trung thế Fuji Electric
Catalog biến tần trung thế Fuji ElectricCatalog biến tần trung thế Fuji Electric
Catalog biến tần trung thế Fuji Electric
 
PARAMETER IDENTIFICATION AND MODELLING OF SEPARATELY EXCITED DC MOTOR
PARAMETER IDENTIFICATION AND MODELLING OF SEPARATELY EXCITED DC MOTOR PARAMETER IDENTIFICATION AND MODELLING OF SEPARATELY EXCITED DC MOTOR
PARAMETER IDENTIFICATION AND MODELLING OF SEPARATELY EXCITED DC MOTOR
 
Motor Current Signature Analysis R K Gupta
Motor Current Signature Analysis R K GuptaMotor Current Signature Analysis R K Gupta
Motor Current Signature Analysis R K Gupta
 
IRJET- Comparative Study of Sensor and Sensor Less Control of Three Phase...
IRJET-  	  Comparative Study of Sensor and Sensor Less Control of Three Phase...IRJET-  	  Comparative Study of Sensor and Sensor Less Control of Three Phase...
IRJET- Comparative Study of Sensor and Sensor Less Control of Three Phase...
 
Comparison Analysis of Zeta PFC Converter to Improve Power Quality Improvemen...
Comparison Analysis of Zeta PFC Converter to Improve Power Quality Improvemen...Comparison Analysis of Zeta PFC Converter to Improve Power Quality Improvemen...
Comparison Analysis of Zeta PFC Converter to Improve Power Quality Improvemen...
 
Design and Implementation of speed control for 3 phase induction motor using ...
Design and Implementation of speed control for 3 phase induction motor using ...Design and Implementation of speed control for 3 phase induction motor using ...
Design and Implementation of speed control for 3 phase induction motor using ...
 
Neural Network Based Voltage and Frequency Controller for standalone Wind Pow...
Neural Network Based Voltage and Frequency Controller for standalone Wind Pow...Neural Network Based Voltage and Frequency Controller for standalone Wind Pow...
Neural Network Based Voltage and Frequency Controller for standalone Wind Pow...
 
DC MOTOR SPEED CONTROL USING ON-OFF CONTROLLER BY PIC16F877A MICROCONTROLLER
DC MOTOR SPEED CONTROL USING ON-OFF CONTROLLER BY  PIC16F877A MICROCONTROLLERDC MOTOR SPEED CONTROL USING ON-OFF CONTROLLER BY  PIC16F877A MICROCONTROLLER
DC MOTOR SPEED CONTROL USING ON-OFF CONTROLLER BY PIC16F877A MICROCONTROLLER
 
Power Factor Correction of Three phase PWM AC Chopper Fed Induction Motor Usi...
Power Factor Correction of Three phase PWM AC Chopper Fed Induction Motor Usi...Power Factor Correction of Three phase PWM AC Chopper Fed Induction Motor Usi...
Power Factor Correction of Three phase PWM AC Chopper Fed Induction Motor Usi...
 
Identifying Three Phase Induction Motor Equivalent Circuit Parameters from Na...
Identifying Three Phase Induction Motor Equivalent Circuit Parameters from Na...Identifying Three Phase Induction Motor Equivalent Circuit Parameters from Na...
Identifying Three Phase Induction Motor Equivalent Circuit Parameters from Na...
 
Matlab Based Analysis of 3-Ø Self-Excited Induction Generator with Nonlinear ...
Matlab Based Analysis of 3-Ø Self-Excited Induction Generator with Nonlinear ...Matlab Based Analysis of 3-Ø Self-Excited Induction Generator with Nonlinear ...
Matlab Based Analysis of 3-Ø Self-Excited Induction Generator with Nonlinear ...
 
Simulation And Hardware Analysis Of Three Phase PWM Rectifier With Power Fact...
Simulation And Hardware Analysis Of Three Phase PWM Rectifier With Power Fact...Simulation And Hardware Analysis Of Three Phase PWM Rectifier With Power Fact...
Simulation And Hardware Analysis Of Three Phase PWM Rectifier With Power Fact...
 
07747986
0774798607747986
07747986
 
Increase productivity and absorption of reactive power for power station with...
Increase productivity and absorption of reactive power for power station with...Increase productivity and absorption of reactive power for power station with...
Increase productivity and absorption of reactive power for power station with...
 
Source current harmonic mitigation of distorted voltage source by using shunt...
Source current harmonic mitigation of distorted voltage source by using shunt...Source current harmonic mitigation of distorted voltage source by using shunt...
Source current harmonic mitigation of distorted voltage source by using shunt...
 
Bo35377383
Bo35377383Bo35377383
Bo35377383
 
Control of Switched Reluctance Generator in Wind Energy System
Control of Switched Reluctance Generator in Wind Energy SystemControl of Switched Reluctance Generator in Wind Energy System
Control of Switched Reluctance Generator in Wind Energy System
 
Iaetsd energy management of induction motor
Iaetsd energy management of induction motorIaetsd energy management of induction motor
Iaetsd energy management of induction motor
 

Mehr von Swathi Venugopal

A new low cost shrm for adjustable-speed pump applications
A new low cost  shrm  for adjustable-speed pump applicationsA new low cost  shrm  for adjustable-speed pump applications
A new low cost shrm for adjustable-speed pump applicationsSwathi Venugopal
 
Harnessing high altitude wind power
Harnessing high altitude wind powerHarnessing high altitude wind power
Harnessing high altitude wind powerSwathi Venugopal
 
A Frequency-based RF Partial Discharge Detector for Low-power Wireless Sens...
A Frequency-based  RF Partial Discharge Detector  for Low-power Wireless Sens...A Frequency-based  RF Partial Discharge Detector  for Low-power Wireless Sens...
A Frequency-based RF Partial Discharge Detector for Low-power Wireless Sens...Swathi Venugopal
 
Visual speech to text conversion applicable to telephone communication
Visual speech to text conversion  applicable  to telephone communicationVisual speech to text conversion  applicable  to telephone communication
Visual speech to text conversion applicable to telephone communicationSwathi Venugopal
 
Save energy save enviornment ii
Save energy save enviornment iiSave energy save enviornment ii
Save energy save enviornment iiSwathi Venugopal
 
Grid integration issues and solutions
Grid integration issues and solutionsGrid integration issues and solutions
Grid integration issues and solutionsSwathi Venugopal
 

Mehr von Swathi Venugopal (6)

A new low cost shrm for adjustable-speed pump applications
A new low cost  shrm  for adjustable-speed pump applicationsA new low cost  shrm  for adjustable-speed pump applications
A new low cost shrm for adjustable-speed pump applications
 
Harnessing high altitude wind power
Harnessing high altitude wind powerHarnessing high altitude wind power
Harnessing high altitude wind power
 
A Frequency-based RF Partial Discharge Detector for Low-power Wireless Sens...
A Frequency-based  RF Partial Discharge Detector  for Low-power Wireless Sens...A Frequency-based  RF Partial Discharge Detector  for Low-power Wireless Sens...
A Frequency-based RF Partial Discharge Detector for Low-power Wireless Sens...
 
Visual speech to text conversion applicable to telephone communication
Visual speech to text conversion  applicable  to telephone communicationVisual speech to text conversion  applicable  to telephone communication
Visual speech to text conversion applicable to telephone communication
 
Save energy save enviornment ii
Save energy save enviornment iiSave energy save enviornment ii
Save energy save enviornment ii
 
Grid integration issues and solutions
Grid integration issues and solutionsGrid integration issues and solutions
Grid integration issues and solutions
 

Kürzlich hochgeladen

cloud computing notes for anna university syllabus
cloud computing notes for anna university syllabuscloud computing notes for anna university syllabus
cloud computing notes for anna university syllabusViolet Violet
 
Landsman converter for power factor improvement
Landsman converter for power factor improvementLandsman converter for power factor improvement
Landsman converter for power factor improvementVijayMuni2
 
ASME BPVC 2023 Section I para leer y entender
ASME BPVC 2023 Section I para leer y entenderASME BPVC 2023 Section I para leer y entender
ASME BPVC 2023 Section I para leer y entenderjuancarlos286641
 
Test of Significance of Large Samples for Mean = µ.pptx
Test of Significance of Large Samples for Mean = µ.pptxTest of Significance of Large Samples for Mean = µ.pptx
Test of Significance of Large Samples for Mean = µ.pptxHome
 
Gender Bias in Engineer, Honors 203 Project
Gender Bias in Engineer, Honors 203 ProjectGender Bias in Engineer, Honors 203 Project
Gender Bias in Engineer, Honors 203 Projectreemakb03
 
Vertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptx
Vertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptxVertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptx
Vertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptxLMW Machine Tool Division
 
Multicomponent Spiral Wound Membrane Separation Model.pdf
Multicomponent Spiral Wound Membrane Separation Model.pdfMulticomponent Spiral Wound Membrane Separation Model.pdf
Multicomponent Spiral Wound Membrane Separation Model.pdfGiovanaGhasary1
 
Clutches and brkesSelect any 3 position random motion out of real world and d...
Clutches and brkesSelect any 3 position random motion out of real world and d...Clutches and brkesSelect any 3 position random motion out of real world and d...
Clutches and brkesSelect any 3 position random motion out of real world and d...sahb78428
 
EPE3163_Hydro power stations_Unit2_Lect2.pptx
EPE3163_Hydro power stations_Unit2_Lect2.pptxEPE3163_Hydro power stations_Unit2_Lect2.pptx
EPE3163_Hydro power stations_Unit2_Lect2.pptxJoseeMusabyimana
 
Power System electrical and electronics .pptx
Power System electrical and electronics .pptxPower System electrical and electronics .pptx
Power System electrical and electronics .pptxMUKULKUMAR210
 
Basic Principle of Electrochemical Sensor
Basic Principle of  Electrochemical SensorBasic Principle of  Electrochemical Sensor
Basic Principle of Electrochemical SensorTanvir Moin
 
Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...
Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...
Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...Amil baba
 
A Seminar on Electric Vehicle Software Simulation
A Seminar on Electric Vehicle Software SimulationA Seminar on Electric Vehicle Software Simulation
A Seminar on Electric Vehicle Software SimulationMohsinKhanA
 
The relationship between iot and communication technology
The relationship between iot and communication technologyThe relationship between iot and communication technology
The relationship between iot and communication technologyabdulkadirmukarram03
 
Transforming Process Safety Management: Challenges, Benefits, and Transition ...
Transforming Process Safety Management: Challenges, Benefits, and Transition ...Transforming Process Safety Management: Challenges, Benefits, and Transition ...
Transforming Process Safety Management: Challenges, Benefits, and Transition ...soginsider
 
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...amrabdallah9
 

Kürzlich hochgeladen (20)

cloud computing notes for anna university syllabus
cloud computing notes for anna university syllabuscloud computing notes for anna university syllabus
cloud computing notes for anna university syllabus
 
Landsman converter for power factor improvement
Landsman converter for power factor improvementLandsman converter for power factor improvement
Landsman converter for power factor improvement
 
Litature Review: Research Paper work for Engineering
Litature Review: Research Paper work for EngineeringLitature Review: Research Paper work for Engineering
Litature Review: Research Paper work for Engineering
 
ASME BPVC 2023 Section I para leer y entender
ASME BPVC 2023 Section I para leer y entenderASME BPVC 2023 Section I para leer y entender
ASME BPVC 2023 Section I para leer y entender
 
Test of Significance of Large Samples for Mean = µ.pptx
Test of Significance of Large Samples for Mean = µ.pptxTest of Significance of Large Samples for Mean = µ.pptx
Test of Significance of Large Samples for Mean = µ.pptx
 
Gender Bias in Engineer, Honors 203 Project
Gender Bias in Engineer, Honors 203 ProjectGender Bias in Engineer, Honors 203 Project
Gender Bias in Engineer, Honors 203 Project
 
Vertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptx
Vertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptxVertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptx
Vertical- Machining - Center - VMC -LMW-Machine-Tool-Division.pptx
 
Multicomponent Spiral Wound Membrane Separation Model.pdf
Multicomponent Spiral Wound Membrane Separation Model.pdfMulticomponent Spiral Wound Membrane Separation Model.pdf
Multicomponent Spiral Wound Membrane Separation Model.pdf
 
Clutches and brkesSelect any 3 position random motion out of real world and d...
Clutches and brkesSelect any 3 position random motion out of real world and d...Clutches and brkesSelect any 3 position random motion out of real world and d...
Clutches and brkesSelect any 3 position random motion out of real world and d...
 
EPE3163_Hydro power stations_Unit2_Lect2.pptx
EPE3163_Hydro power stations_Unit2_Lect2.pptxEPE3163_Hydro power stations_Unit2_Lect2.pptx
EPE3163_Hydro power stations_Unit2_Lect2.pptx
 
Power System electrical and electronics .pptx
Power System electrical and electronics .pptxPower System electrical and electronics .pptx
Power System electrical and electronics .pptx
 
Présentation IIRB 2024 Chloe Dufrane.pdf
Présentation IIRB 2024 Chloe Dufrane.pdfPrésentation IIRB 2024 Chloe Dufrane.pdf
Présentation IIRB 2024 Chloe Dufrane.pdf
 
Basic Principle of Electrochemical Sensor
Basic Principle of  Electrochemical SensorBasic Principle of  Electrochemical Sensor
Basic Principle of Electrochemical Sensor
 
Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...
Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...
Popular-NO1 Kala Jadu Expert Specialist In Germany Kala Jadu Expert Specialis...
 
A Seminar on Electric Vehicle Software Simulation
A Seminar on Electric Vehicle Software SimulationA Seminar on Electric Vehicle Software Simulation
A Seminar on Electric Vehicle Software Simulation
 
Lecture 2 .pptx
Lecture 2                            .pptxLecture 2                            .pptx
Lecture 2 .pptx
 
The relationship between iot and communication technology
The relationship between iot and communication technologyThe relationship between iot and communication technology
The relationship between iot and communication technology
 
Transforming Process Safety Management: Challenges, Benefits, and Transition ...
Transforming Process Safety Management: Challenges, Benefits, and Transition ...Transforming Process Safety Management: Challenges, Benefits, and Transition ...
Transforming Process Safety Management: Challenges, Benefits, and Transition ...
 
計劃趕得上變化
計劃趕得上變化計劃趕得上變化
計劃趕得上變化
 
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...
 

Estimation of induction motor operating power factor.

  • 1. Estimation of Induction Motor Operating Power Factor From Measured Current and Manufacturer Data
  • 2. Estimation of IM Operating PF From Measured Current and Manufacturer Data index Sl No Tittle Page No 1 Introduction 02 2 Background Information 04 3 Current –Only, Pf Estimation 06 4 Power Factor: From Voltage, Current ZC 11 5 Power Factor: From Instantaneous Power 14 6 Discussion Of Results 16 7 Conclusion 20 8 References 21 1
  • 3. Estimation of IM Operating PF From Measured Current and Manufacturer Data introduction “ THREE-PHASE induction motors (IM) are industrial work-horses, responsible for consumption of 40–50% of generated electrical power. ” 2
  • 4. Estimation of IM Operating PF From Measured Current and Manufacturer Data  Recently there has been a lot of focus on IM protection at LV, &MV levels.  These protection devices typically monitor the motor current and/or voltage to provide the motor protection functionalities  One of the interesting parameters to monitor is the operating power factor (PF)  Traditionally, to monitor the operating PF of the IM, one would require both the voltage and the current A low cost method of determining the operating PF of the IM using only the measured current and the manufacturer data is developed. 3
  • 5. Estimation of IM Operating PF From Measured Current and Manufacturer Data BACKGROUND INFORMATION IM equivalent circuit. Leakage reactance I1 = Im+I1 ’ Load v1 I1 r1 X1 rC Xm I1’ X2’ r2’ s component Exciting component Im core-loss resistance magnetizing reactance stator Rotor 4
  • 6. Estimation of IM Operating PF From Measured Current and Manufacturer Data Power Factor and Motor Load  휽ퟎ in the range 75 –85 ie, stator PF at no load may be as low as 0.1–0.3.  Typically, stator PF of about 0.8–0.9 at 80–100% of the full-load  I1’ N1= I2’ N2 5
  • 7. Estimation of IM Operating PF From Measured Current and Manufacturer Data CURRENT –ONLY, PF ESTIMATION  Total input electrical apparent power , 푷 = ퟑ푽푰  Active power, for supplying the load ,푷 = ퟑ푽푰 cos ∅  PF = 푷 푷 = cos ∅ Eqn 1  I= 푰풂풄풕풊풗풆 ퟐ + 푰풓풆풂풄풕풊풗풆 ퟐ  푰풂풄풕풊풗풆 = I cos ∅ , 푰풓풆풂풄풕풊풗풆= I sin ∅  푰풓풆풂풄풕풊풗풆=I sin cos−ퟏ(푷푭) Eqn 2 PF = 푐표푠 ∅ = 1 − 푠푖푛∅2 = 1 − ( 퐼푟푒푎푐푡푖푣푒 퐼 )2 Eqn 3 6
  • 8. Estimation of IM Operating PF From Measured Current and Manufacturer Data  푰풓풆풂풄풕풊풗풆 remains constant, it can be estimated from nameplate data using 푰풓풆풂풄풕풊풗풆= I sin cos−ퟏ(푷푭)  At no-load condition, there is no active current flow. So, at no-load, I= 푰풓풆풂풄풕풊풗풆 PF = 0 ( 퐼PF= 1 − ( 푟푒푎푐푡푖푣푒 퐼 )2 )  As motor load increases the PF will increase toward unity. Motor load increases Total motor I increase 푰풓풆풂풄풕풊풗풆 remains constant ( 푰풓풆풂풄풕풊풗풆 푰 )ퟐ Decreases  Physically, at no-load, there is not much mechanical resistance, so the whole circuit is mostly inductive due to the stator coils, causing low PF. 7
  • 9. Estimation of IM Operating PF From Measured Current and Manufacturer Data Basic Algorithm  Estimate the 푰풓풆풂풄풕풊풗풆 from the nominal PF out of the nameplate data. ( 푰풓풆풂풄풕풊풗풆=I sin cos−ퟏ(푷푭))  Estimate the operating PF from measured motor current & constant 푰풓풆풂풄풕풊풗풆 “ It would not require synchronized voltage and current measurement like in the displacement PF measurement principle.” 8
  • 10. Estimation of IM Operating PF From Measured Current and Manufacturer Data experimental setup Load supply Motor supply ABB Lv drive IM 3 ph Load Motor (7.5kw) Test Motor (2.2 kw) two pole pairs IM, M2AA LA4 Motor current measureme nt Main supply (50 Hz) IM 3 ph 9
  • 11. Estimation of IM Operating PF From Measured Current and Manufacturer Data NAME PLATE RATING OF THE TEST MOTOR TYPE ABB M2AALA4. NOMINAL VOLTAGE 4 00V NOMINAL CURRENT 4.9A RATED POWER 2.2KW RATED PF 0.81 RATED SPEED 1430 RPM 푰풓풆풂풄풕풊풗풆=I sin cos−ퟏ(푷푭) = 4.9* Sin (cos−1 0.81) =2.87 MEASURED I,CALCULATED PF FROM CURRENT-ONLY METHOD AT DIFFERENT LOAD Measured CURRENT I(A) I/푰풏풐풎풊풏풂풍 (%) PF 3.01 61.43 .30 3.23 65.92 .46 4.37 89.18 .75 5.21 106.33 .83 6.21 126.73 .89 PF= 1 − ( 퐼푟푒푎푐푡푖푣푒 퐼 )2= 2.87 3.01 1 − ( )2 = 0.3 10
  • 12. Estimation of IM Operating PF From Measured Current and Manufacturer Data Power Factor: From Voltage, Current ZC Basic Algorithm  Synchronized measurement of the supply voltage and the motor current are done.  Displacements in the ZC timings between the voltage (taken as reference) and the current signals are estimated.  Estimate the PF using the equation ±x ms : Deviation between the current ZC w.r.t. the voltage ZC,  풇ퟎ ∶ 퐒upply frequency. PF=풄풐풔( 풙 ( ퟏ 풇ퟎ ) X ퟑퟔퟎퟎ)  The current ZC deviation is positive or negative w.r.t. The voltage would decide whether the PF is lagging or leading. 11
  • 13. Estimation of IM Operating PF From Measured Current and Manufacturer Data experimental setup Load supply Motor supply ABB Lv drive IM 3 ph Load Motor (7.5kw) Tektronix Voltage probe Current hall-sensor probe Test Motor (2.2 kw) two pole pairs IM, M2AA LA4 Main supply (50 Hz) oscilloscope Agilent IM 3 ph 12
  • 14. Estimation of IM Operating PF From Measured Current and Manufacturer Data PF MEASUREMENT USING DISPLACEMENT IN THE ZC OF THE SYNCHRONIZED SUPPLY VOLTAGE AND MOTOR CURRENT AT 66% CURRENT LOAD.  ±x ms : 3.4 ms ,풇ퟎ = ퟓퟎ  Pf =풄풐풔( 풙 ( ퟏ 풇ퟎ ) X ퟑퟔퟎퟎ) =cos( 3.4 20 푿 ퟑퟔퟎퟎ) = 0.48 RMS CURRENT,TIME DEVIATION BETWEEN ZC OF VOLTAGE &CURRENT, PF FROM DISPLACEMENT METHOD AT DIFFERENT LOAD RMS current I(A) ZC time difference (ms) PF 2.97 4.6 0.12 3.00 3.4 0.48 3.54 2.8 0.64 4.24 2.1 0.79 5.23 1.6 0.87 13
  • 15. Estimation of IM Operating PF From Measured Current and Manufacturer Data Power Factor: From Instantaneous Power Basic Algorithm  Estimate instantaneous power per phase (i.e., point-by- point multiplication of the two waveforms) from the synchronized supply voltage and the motor current Average power (푃 ) per phase from the measurement in the scope. Estimate the PF using the equation : PF = 푃 푉퐼 14
  • 16. Power factor measurement using instantaneous power from the measured synchronized supply voltage and the motor current at 66% current load. 푃 =328.525 V=230 I=3 PF = 푃 푉퐼 = 328.525 230 푋 3 = 0.476 RMS CURRENT,RMS VOLTAGE , INSTANTANEOUS POWER ,POWER FACTOR AT DIFFERENT LOAD RMS current (A) RMS voltage (v) Instantaneou s power(w) PF 2.97 230 72.86 0.1 1 3.00 230 328.53 0.4 8 3.54 230 547.48 0.6 7 4.24 230 774.67 0.7 9 5.23 230 1014.32 0.8 4 Estimation of IM Operating PF From Measured Current and Manufacturer Data 15
  • 17. Estimation of IM Operating PF From Measured Current and Manufacturer Data DISCUSSION OF RESULTS METHOD I(A) PF I(A) PF From Measured Current 3.00 0.221 4.24 0.71 From Voltage, Current ZC 3.00 0.48 4.24 0.79 From Instantaneous 3.00 0.48 4.24 0.79 Power “The PF estimation error using the current-only method is about +0.04 , except at the no-load condition, where it is about−0.18 . This could be because, the sensitivity of the motor current measurement module might not be very perfect at no-load condition.” 16
  • 18. Estimation of IM Operating PF From Measured Current and Manufacturer Data  The proposed method relies on the fact that the inductance of the total circuit remains constant.  This rule might be violated if the motor is supplied via a variable speed drive.  Most modern drive systems usually measure both voltage and current and can provide PF measurement . Hence, no need for cheaper calculation of PF.  it is assumed that manufacturers comply with the relevant IM manufacturing standards, providing rated values with acceptable accuracy.  Estimation of IM operating PF could be used for PF compensation 17
  • 19. Estimation of IM Operating PF From Measured Current and Manufacturer Data  Under no-load condition, the referred reactance of the rotor X2’ would be absent.  The no-load current would comprise of the magnetizing current only. ie the no-load current would not be a good representative of the total reactive current  So, the reactive current estimated from the rated condition, would not miss any inductive elements.  For bigger IMs with low I(no−load)/I(rated) ratio, the assumption to use I reactive = constant for light loads might lead to high errors in the PF estimation.  Higher power machines usually come with MV or LV drives already provided with the PF computation. 18
  • 20. Estimation of IM Operating PF From Measured Current and Manufacturer Data Measured current (A) Underload protection using motor current & power factor Measured current (A) 푁표푚푖푛푎푙 푐푢푟푟푒푛푡 (퐴) Power factor Measured current (A) 푁표푚푖푛푎푙 푐푢푟푟푒푛푡 (퐴)  At low loads the nonlinear curve of the PF provides better resolution  It challenging to accurately measure the low current change from small load change at low loading. 19
  • 21. Estimation of IM Operating PF From Measured Current and Manufacturer Data CONCLUSION  Low cost method of determining the operating PF of the IM using only the measured current and the manufacturer data typically available from the nameplate and/or datasheet.  This would provide a cheaper solution to under load protection, e.g., in pump applications, using the operating PF, without requiring the voltage sensors.  Operational PF can also be used for PF compensation to improve the power quality. 20
  • 22. Estimation of IM Operating PF From Measured Current and Manufacturer Data REFERENCE  P.S.Bimbhra, electrical machinery. New delhi, india: khanna publishers,,  “Identification of induction motor equivalent circuit parameters using the single-phase test,” IEEE trans. Energy convers.  Abb. (2009). Manual for low voltage motor. Http://www.Abb.Com/motors.  Abb. (2010). LV drives, model ACS800. Www.Abb.Com/drives  D. Sharon, “power factor definitions and power transfer quality in no sinusoidal situations,”ieee trans. Instrum.  “Power-factor compensation of electrical circuits,” IEEE control syst. 21
  • 24. Estimation of IM Operating PF From Measured Current and Manufacturer Data ANY QUESTION S? 23

Hinweis der Redaktion

  1. in Fig. 5. In Fig. 5, we have a test motor (2.2 kW) [12] supplied from the 50-Hz mains. There is a second motor of slightly bigger size (7.5 kW) [12] directly coupled to the test motor, acting as a loading motor to the test motor. The loading motor is supplied via an ABB drive [13] so that the torque of the loading motor can be changed in order to test different loading conditions for the test motor. In order to load the test motor, the direction of rotation of the loading motor should be opposite to that of the test motor. This can be done via the drive, as indicated in Fig. 5. The test motor is an ABB three-phase, two pole pairs IM, type M2AA LA4 [12]. Fig. 6 shows the nameplate ratings of the test motor. Stator winding of the motor was connected in star (Y). The effective nameplate ratings are given in Table I. For the proposed PF measurement, the motor current of the test motor is measured using a motor current measurement module. To validate the proposed current-only PF estimation, the actual PF also needs to be measured. For that purpose, a high-resolution oscilloscope from Agilent [14] is used to make synchronized measurement of the supply voltage and the motor current. The oscilloscope has four input channels. So, two phases of the supply voltage and two phases of the motor currents are
  2. in Fig. 5. In Fig. 5, we have a test motor (2.2 kW) [12] supplied from the 50-Hz mains. There is a second motor of slightly bigger size (7.5 kW) [12] directly coupled to the test motor, acting as a loading motor to the test motor. The loading motor is supplied via an ABB drive [13] so that the torque of the loading motor can be changed in order to test different loading conditions for the test motor. In order to load the test motor, the direction of rotation of the loading motor should be opposite to that of the test motor. This can be done via the drive, as indicated in Fig. 5. The test motor is an ABB three-phase, two pole pairs IM, type M2AA LA4 [12]. Fig. 6 shows the nameplate ratings of the test motor. Stator winding of the motor was connected in star (Y). The effective nameplate ratings are given in Table I. For the proposed PF measurement, the motor current of the test motor is measured using a motor current measurement module. To validate the proposed current-only PF estimation, the actual PF also needs to be measured. For that purpose, a high-resolution oscilloscope from Agilent [14] is used to make synchronized measurement of the supply voltage and the motor current. The oscilloscope has four input channels. So, two phases of the supply voltage and two phases of the motor currents are