2011 - Technical Study Report - Energy Efficiency Improvemen

7/27/2019 2011 - Technical Study Report - Energy Efficiency Improvemen

1/85Energy Eciency Improvements or Motor & Its Drive Systems

ENERGY EFFICIENCYIMPROVEMENTS FOR MOTORS &

ITS DRIVE SYSTEMS

echnical Study Report



This report was produced under the project entitled Supporting Action

on Climate Change through a Network of National Climate Change Focal

Points in South-east Asia (SEAN-CC) implemented by UNEP and funded by

Ministry of Foreign Affairs of the Government of Finland.Dec 2011



ABOUT THE TECHNICAL STUDY REPORT

Continuing increase o electricity prices.

With limited natural resources and the ever increasing global demand or energy, it only stands toreason that energy costs will continue to increase into the uture. As energy costs rise around the world,

the incentive or acilities to operate their equipment more eciently will compound over time. Tere

are government regulations use to enorce conservation, and compensatory means (e.g., special rate

taris) that reward users or using less energy.

Energy eciency improvements such as through replacement o old standard electric motors,

requently burnt motors, or oversized electric motors by High Eciency Motors (HEMS) and

improving its drive systems - can be an option by which a company can oset their electricity expenses.

Global move towards decarbonisation.

Te international movement towards minimizing eects o climate change coupled with clamor

rom consumers or companies to leave as little carbon ootprint in the manuacture o their products

motivates rms to explore possibilities or lowering their carbon ootprints. Energy eciency options

will be looked at more earnestly, especially so when these are embedded as part o their corporate social

responsibility (CSR) objectives.

Tis echnical Study Report (RS) provides the ideas and technologies to improve energy eciency

o motors and its drive systems, increase equipment reliability, reduce expense on electricity, and help

minimize eects o climate change and lowering carbon ootprints.



SECTION 1: INTRODUCTION 1

1.1 ype o Electric Motors 11.2 Electric Motor Drive System Applications 3

1.3 Example o Motor Application 4

SECTION 2: FACTORS AFFECTING MOTOR EFFICIENCY 62.1 Factors Aecting Motor Eciency 7

A. Motor Perormance 7

B. Voltage Variance 7

C. Voltage Unbalance 8

D. Motor Load 8

E. otal Harmonic Distortions 9

F. Power Factor 9

2.2 Rewound Motoss 9

2.3 Common Motor Practices that Degrade Liecycle and Eciency o Motor 11

2.4 Piping and Ducting Systems 13

SECTION 3: ENERGY EFFICIENCY TECHNOLOGIES 163.1 Energy Audit 173.2 Standards 17

3.3 Motor Eciencies 23

3.4 Repair or Replacement Based on Liecycle Approach 25

3.5 Voltage Stabilization 26

3.6 Proper Motor Sizing 27

3.7 ISO50001 - Energy Management Standards 28

SECTION 4: RECOMMENDATIONS 294.1 Electric Motor Asset Management 30

4.2 Strategies or Electric Motor Drive System (EMDS) Improvement 34

4.3 Electric Motor Manuactures 36

4.4 Voltage Stabilizer Manuacturers 39

Contents



LIST OF TABLES

able 1 - Motor eciency classes in dierent countries and the corresponding 18international standard

able 2 - imeline or electricmotor eciency classes, testing standards and minimum 19energy perormance

able 3 - Share o eciency class IE3 in electric motor sales by size, United States (2003) 22

LIST OF FIGURESFigure 1 - ype o motors 3Figure 2 - Eect o voltage variations on induction motor character 8Figure 3 - Impact o misalignment in power consumption 9Figure 4 - 97.9 watts is drawn by motor with aligned shat 9Figure 5 - 122.1 watts is drawn by motor with misaligned shat 9Figure 6 - Stator with unequal turns per coil 10Figure 7 - Coil span 10Figure 8 - Open drip proo motor 11Figure 9 - Open terminal box 11Figure 10 - Deormed rotor ns that will cause unbalance 11Figure 11 - High vertical vibration level caused by weak oundation resonance 11Figure 12 - Misalign pulley and over belt tensioned 12

Figure 13 - RU 301. No improvement on its perormance ater repair 12Figure 14 - Vibration results o scrubber# 1 13Figure 15 - Scrubber 1 structure 13Figure 16 - Alignment result prior to motor replacement 13

SECTION 5: OTHER ENERGY EFFICIENCY IMPROVEMENTS 415.1 Rewinding 47

5.2 Variable Frequency Drives 43

5.3 Power Quality 44

5.4 Power Factory Improvement 46

5.5 esting and Equipment Requirement 48

SECTION 6: ANNEX 50Annex 1 - ables with Eciency Classes: IEC 60034-30 92008) - 50 HZ 51

Annex 2 - ables with Eciency Classes: IEC 60034-30 92008) - 60 HZ 52

Annex 3 - ables with Eciency Classes: NEMA Premium 53

Annex 4 - ISO 10816-3 Vibration Severity Chart 54

Annex 5 - Alignment olerance 54

ABBREVIATIONS 55GLOSSARY 56REFERENCE 58

SECTION 7: CASE STUDIES 60



Figure 17 - Common pipe conguration problems and how to correct them 14Figure 18 - 900 Pipe Elbow had contribute much o the axial vibration 15Figure 19 - Vibration results o pump with 900 pipe elbow 15Figure 20 - Eciency classes or ourpole motors o standard 18

IE3, IE2 and IE1 classes, and the new IE4 classFigure 21 - ypical IEC motor nameplate 20

Figure 22 - ypical NEMA motor nameplate 20Figure 23 - Market share o eciency classes in the United States (200106) 21Figure 24 - Motor eciencies in Canada beore and ater introduction in 1997 o 21

Energyeciency regulations or general purpose industrial motorsFigure 25 - Market share o eciency classes in Europe under the CEMEP 22

voluntary agreementFigure 26 - Motor loading perormances 24Figure 27 - Vibration analysis results 25Figure 28 - IE3 premium - eciency motor 26Figure 29 - Example o how downsizing can pay or a more ecient motor 27

Figure 30 - 125 HP motor load analysis 31Figure 31 - Estimate payback time /ROI (Year) investing on HEM versus repair o motor 32Figure 32A - Estimated energy savings rom 20HP/15kW to 100HP/75kW 33Figure 32B - Estimated energy savings rom 1HP/0.745kW to 15HP/11kW 33Figure 33 - Estimated carbon dioxide emissions 34Figure 34 - Strategies or EMDS reliability 34Figure 35 - Mean-length-turn 41Figure 36 - Low slot ll 41Figure 37 - SAMAIC 8080 computerize motor rewinding machine 42

Figure 38 - Adjustable concentric heads 42Figure 39 - Improved slot ll 43Figure 40 - Improvement o HD and Ie ater correct selection o passive 45

harmonic lters (P = 22kW)Figure 41 - System improvement or harmonics 46Figure 42 - Components o motor current 46Figure 43 - Motor current with PF correction capacitors 47



Section1



Section2



Section2

13

years. Tis requires investment on predictive

maintenance such as vibration analysis, electricalsignature analysis, thermal scanner, and motor

circuit analyzer. Use o eye-ball or string to align

pulleys will not work rather than increase power

consumption. Again, this requires investment on

precision instruments such as laser alignment,

proessional bearing tools, etc.

2.4 Piping and Ducting Systems

Designers oten overlook the energy costs o

piping or duct systems. Te eects on power

drawn by the motor due to unnecessary pressure

drops by avoiding sharp bends, expansions, and

contractions and by keeping piping or ducting as

straight as possible. For example, orienting valves

and system equipment so that they are in line

with the pipe run is one useul rule o thumb.

Since centriugal pumps operate most eectivelywhen the inlet fow has a uniorm prole, systems

should be designed to avoid non-uniorm fow

13



Section2



Section3



Section3

100% ull-load current and high operating

temperature. Tis is because there are quality

problems in ensuring turns/coil and coil span o

magnet wires are within the required specication

o the motor. Worst the original winding data

is altered, and subsequent rewinding shortens

motor lie-cycle, and reduces motor eciency

rom 5 7.6%.

Example Oil Recycling Plant

An oil recycling plant utilized a reconditioned

and/or rewound standard motors in its acility.

It has 77 motors ranging rom 1 50 HP, 230

VAC. An audit on motor perormance is shown

in Figure 26 & 27 or 7.5HP motor, 1800 RPM.

Te company is spending US$ 9,225.00 per

monthly on electricity bill.

Energy Eciency (EE) improvements based on

the results are as ollows:

23



Section3

85% x IFLAcheck losses;b) 75-85% x IFLAhigh eciency;c)



Section3



Section4



Section4

85% x IFLA check losses;b) 75-85% x I

FLAhigh eciency

c)



Section4



Section5



Section5

2000 hrs/yr)

Te potential energy savings derived rom

reducing a motors power to manage its speed

are approximated by the Anity Laws. Teseengineering laws are used to express the

relationship between fow, head, and consumed4 http://www.motorsmatter.org/resources/asds.html

Calibration Date=3-3-11Job#=7 HP=25.0 RPM=1300HI-POT=1880V MegOhm=>999

SURGE=1880V TURNS=>95% QUALITY=>95%PI=not testedResistance: AB=0.408 BC=0.408 CA=0.408 Ohms

ALPS Maintaineering Services, Inc.Plant Address: Isateram Bldg., Holiday Homes, BrgySan Antonio, San Pedro, Laguna.Tel No. 842 5405/806 3851Email Address: [email protected]

PI Black curveA-B Red curveB-C Green curve

C-A Blue curve

SWMETSAMATIC Data Acquisition

43



Section5



Section6



Section7



Section7

95% QUAL-ITY=>95%PI=not tested

Resistance: AB=0.408 BC=0.408CA=0.408 Ohms

ALPS Maintaineering Services, Inc.Plant Address: Isateram Bldg., HolidayHomes, BrgySan Antonio, San Pedro, Laguna.

Tel No. 842 5405/806 3851Email Address: [email protected]

PI Black curve

A-B Red curveB-C Green curveC-A Blue curve

SWMETSAMATIC Data Acquisition

Samatic WInding Machine

69



Section7

100% o its ull

load current.. Motor eciency at 100% FLC

is 91.7%.

5. Rewindconventional

, Price = US$ 220.00

6. RewindSamatic, Price = US$ 303.007. urns/coil and/or Mean-length o turn are

not equal; the motor eciency is reduced by

7.6% and operating >100% o its motor load,

equivalent to 84.1%.

Conclusion

Quality workmanship is seldom considered in

making decisions. Te lowest bidder is always

the basis in awarding the rewinding works. Te

rewinding cost using conventional method

is very cheap but the overall operating cost is

much higher as shown by Financial Loss o US$3,457.00. Cheap motor rewinding price

ends up high operating cost.

At 7000 operating hours per year, the nancial

losses is quite high and it is worth to consider

buying a new HEM worth US$ 1,236.00 +

reight and taxes. I there are oers lower than the

price mentioned, be careul to buy rom a reliable

and trusted supplier. A 5.6kW with Frame 215

maybe overlook as 7.5kW and o course with

same rame number. Motor dimensions areexactly the same, but o dierent capacity!!

70



Section7



Section7

than

75%. Figure 2 enumerate dierent electric motor

problems detected with vibration analysis.

CASE STUDIES C PREDICTIVE MAINTENANCE

The Problem to Address

A 7.5 kW High Eciency Motor with

Equipment ag Name: Jockey Pump-Motor,

12-Amps Full-load Current, 440V, 3-phase had

experienced water leakage at pump inboardbearing and high vibration level. Te average

current drawn by directly coupled motor was

10.9 Amps with a loading capacity o 90.83%

exceeding the 75 - 85% peak eciency. Te

estimated motor eciency is 86.5% (Red line

based on Figure 1).

25 50 75 1000

75

80

85

90

70

95

100

79.17%

90.83%

88.5%

86.5%

Percent Efciency

Percent Rated Load

5 hp

10 hp

50 hp

100 hp

500 hp1000 hp

5000 hp

Figure 1 - Eciency vs % Rated LoadCourtest of EASA Technical Manual

No-Load Testing Full-Load Testing

Unbalance Eccentric rotor

Bent shat Eccentric air gap

Mechanical looseness Eccentric stator

Bearing damage Loose iron

Misaligned bearings Shorted laminations

Sot oot Improper phasing

Rotor rub Problems with rotor bars

Resonance Loose coils

Electric Motor Problems Detected withVibration Analysis

Figure 3 - Vibration results beore the repair was perormed

Te vibration results indicated misalignment,

worn-out shat and bearing deects as shown

in Figure 3. Te colors refected in Figure 3 aresimilar to rac Lights used in the intersection

o a street. Te Red color means danger;

Figure 2Courtest of EASA Technical Manual 2007

75



Section7


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Section7

Conclusion1

In the continuous stress o a production

environment, there is oten little opportunity to

pause and reconsider the way in which electric

motors are purchased, maintained, and replaced.

As long as nobody is given the responsibility or

company-wide electric motor asset management,

employees in the production environment will

continue to act on an ad hoc basis, maintaining,

repairing, and replacing motors in the same waythey have in the past, without insight into the

otal Cost o Ownership. Te obvious driver

or change usually escapes notice since the losses

that are generated by a sub-optimal motor are

scattered among dierent cost centers: energy

consumption, material waste, lost revenue, extra

working hours, reduced productivity, reduced

production quality, et cetera. By assigning

an individual either inside the companyor outsourced to electric motor asset

* Item 11 - Terminal Cash Flow

Figure 12 - Discounted Payback Period

YearProject Relevant

Cash Flow (a)P.V. Factor (b)

P.V. Cash Flowc = a x b

Total to Date

1 88,161 0.893 78,727 $78,727

2 88,161 0.797 70,264 $148,991

3 88,161 0.712 62,770 $211,762

4 88,161 0.636 56,070 $267,832

5 88,161 0.567 49,987 $317,819

6 10,126 0.567 5,741 $323,569

Documents

2011 - Technical Study Report - Energy Efficiency Improvemen