The document outlines the Life Expectancy Analysis Program (LEAP) for electrical machine insulation, focusing on its methodology, benefits, and statistical analysis of failures. LEAP provides a systematic approach to maintenance, facilitating optimized strategies and extending the life of machines by assessing conditions and recommending suitable actions. The program leverages extensive data collected globally to inform maintenance planning and improve operational reliability.

1. Cajetan Pinto, Global R&D Manager Machines Service, March 4, 2009
Life Expectancy Analysis Program
for Electrical Machine Insulation
© ABB Group
October 29, 2009 | Slide 1

2. Presentation overview
Life Cycle Management Approach
Reliability and failure statistics
Planning your Strategy
LEAP Methodology & Use
LEAP Standard
Case Studies
Benefits
© ABB Group
October 29, 2009 | Slide 2

3. Life Cycle Concept
Value to Optimized Maintenance Line
customer Continuous
through Upgrading/
maintenance Replacement
Maintenance
Overhaul
Aging
Repair
Warranty Period Upgrade and Replacement & Recycle Period Time
Modernization Period
Maintenance Period
Customer Project Lifecycle
© ABB Group
October 29, 2009 | Slide 3

4. Total cost of operation (TCO)*
TCO includes:
• Purchase price
• Specifications 74 %
• Transportation
• Storage
• Installation
• QA
• Reliability
• Electricity
• Repairs
• Administration
• Inventory
• etc
17.4 %
4.9 %
1% 2.7 %
Installation Purchase Cost of repair Reliability Electricity
* Information provided by MachineMonitor based on survey of 6000 machines
© ABB Group
October 29, 2009 | Slide 4

5. Basis of Analysis: Stress & Strength v/s Time
Strength
Premature Failure
Stress, strength
Failure
Transients
Stress
Residual Life
Time
© ABB Group
October 29, 2009 | Slide 5

6. Life Expectancy Analysis: Benefits
Strength Condition assessment and taking
suitable actions at this point.
Adv. 1: No Premature Failure
Transients
Failure
Stress
Residual Life
Adv. 2: Increase in Life
© ABB Group
October 29, 2009 | Slide 6

7. Reliability
&
Failure Statistics
© ABB Group
October 29, 2009 | Slide 7

8. Failure statistics: IEEE Survey 1985-1987
Bearing
Winding
11%
5%
3% 37% Rotor
6%
Shaft/coupling
5% Brushes/slipring
33% External devices
Detection during Normal operation Not specified
© ABB Group
October 29, 2009 | Slide 8

9. Failure statistics : IEEE Survey 1985-1987
Bearing
10% Winding
4%
7%
Rotor
Shaft/coupling
8%
2% Brushes/slipring
8%
61% External devices
Not specified
Detection during maintenance or test
© ABB Group
October 29, 2009 | Slide 9

10. Failure Statistics: HV Motors Petrochemical Industry
1999
Distribution of Failures for motors below 2000KW Bearing
Stator Windings
1.20%
14.60% Rotor- Bars/rings
2.80% 57.40%
Shaft or coupling
5.60%
External device
18.40%
Not Specified
Distribution of Failures for motors equal and above 2000KW
7.89 5.26 7.89 0.00 For Machines less than 2000 kW
IEEE
anti-friction bearings are commonly
18.42
transactions on used which are more likely to fail
industry
applications .
vol. 35. no. 4.
july/august 1999 For Machines above 2000 kW
sleeve bearings are often used
60.53 which are less likely to fail
© ABB Group
October 29, 2009 | Slide 10

11. Factors affecting Failure rate
Total Failure Rate Vs Age %wdg Failure Rate
7
3.5
6
3
5 2.5
4 2
% %
3 1.5
2 1
1 0.5
0
0
3000-5000 6000 6600-10500 11000-
0-5 5.1-10 10.1-15 15.1-20 20.1-25 25.1- 13800
Age (Years) Voltage(Volts)
%wdg. Failure Rate Wdg Failure Rate
1.4
1.2 2.5
1 2
0.8 1.5
%
0.6 %
Series1 1 Series1
0.4
0.2 0.5
0 0
2 4 6 8 10 1 or less More than 1
Pole Number No of Starts/day
© ABB Group
October 29, 2009 | Slide 11

12. Stator winding failures
Persistent
Overloading
Other 7% High Ambient
14% Temperature
8%
Normal
deterioration with
age Abnormal Moisture
18% 18%
Abnormal Voltage
Poor Ventilation/ 5%
Cooling Abnormal
8% Frequency
1%
Aggressive
Poor Lubrication High Vibration
chemicals
5% 9%
7%
FAILURE CONTRIBUTORS
© ABB Group
October 29, 2009 | Slide 12

13. Planning your maintenance STRATEGY
Condition Life-time
Protection Monitoring Estimation
• on-line, but not • on-line + off-line
• continuous, on-line,
action taken in real time necessarily continuous • analysis and action
• analysis and action is subsequent to data
• to limit the damage or
subsequent to data collection
prevent operation under
abnormal conditions collection • detects life limiting
• prevents failure by taking defects at the incipient
steps with short term stage, useful in both long
planning for maintenance term planning and short
term planning for
maintenance
MST, ARGUS, DLI, PD, LEAP
Telemetry, etc
© ABB Group
October 29, 2009 | Slide 13

14. LEAP …… not just a step ahead
What is LEAP?
Lifetime Expectancy Analysis Program or
LEAP is a unique Maintenance Tool for the
Stator Winding Insulation of Electric
Machines.
LEAP provides information on Machine
winding and expected life, and will optimize
the Machine Maintenance Plans
LEAP developed by ABB Machines Service,
India, is in use for over 12 years, with a
database of measurements and analysis in
excess of 4000 machines worldwide
Measurements are performed by Local or
Global ABB Service centers and data
analyzed at the LEAP Center of Excellence
LEAP is not just a package of
inspections; it is a systematic
approach to managing Machine
Maintenance
© ABB Group
October 29, 2009 | Slide 14

15. Level Based Inspections
Opportunities for Inspection Schedule
Inspections
Basic When the machine is Every 5% of the estimated lifetime
operating
Standard When the machine is Every 10% of the estimated lifetime
stopped but assembled
Advanced When the machine is Every 25% of the estimated lifetime
stopped and partially
dismantled
Premium When the machine is Every 50% of the estimated lifetime
stopped and rotor removed
90
75
Confidence Level
60
45
30
15
0
Basic Standard Advanced Premium
© ABB Group
October 29, 2009 | Slide 15

16. Level Based Inspections
Solution Packages Deliverables
Levels
Basic Data collection (on site or remote): Life Expectancy Analysis 65% Confidence
Level
Operational hours, voltage, current, power, slip,
Condition Based Inspection and Maintenance
Starts/Stops, Temperature (Winding, Coolant and Ambient),
Plan
Duty cycle & loading pattern, Failure and Maintenance
history, Information on power supply, breaker-cable
configuration, etc
Standard Basic Data Collection Condition Assessment of Stator Windings for
Polarization Depolarization Current Analysis PDCA Contamination, ageing, looseness,
Tan Delta & capacitance Analysis delamination, stress grading system
Life Expectancy Analysis 80% Confidence
Non-Linear Insulation Behaviour Analysis
Level
Partial Discharge Analysis Condition Based Inspection and Maintenance
Plan
Advanced Standard Data Collection Condition Assessment of Stator Windings with Standard
Visual Inspection on end windings Package + End-winding assessment
Life Expectancy Analysis 85% Confidence
Partial Discharge Probe measurements & Dynamic Level
Mechanical Response of Windings
Condition Based Inspection and Maintenance
Stress analysis of End-windings Plan
Premium Advanced Data Collection Condition Assessment of Stator Windings with
Wedge Tightness Map & Coupling resistance measurements Advanced Package + slot region assessment
Life Expectancy Analysis 90% Confidence
Visual inspection, including slot areas
Level
Stress analysis of Windings Condition Based Inspection and Maintenance
Plan
© ABB Group
October 29, 2009 | Slide 16

17. LEAP Methodology
&
Use of LEAP
© ABB Group
October 29, 2009 | Slide 17

18. LEAP methodology
Collection of Data
Operating data, test measurements and
machine information
Analysis of Data
ABB has developed UNIQUE analytical
tools aimed at life assessment
Calculation of Stresses
Life Expectancy Analysis is performed and
factors and conditions that affect lifetime
are identified
Estimating Life & Condition Based
Maintenance
Lifetime is estimated with different
Confidence levels depending on the LEAP
package
Possible further inspections, maintenance,
replacements or even upgrades are drawn
up
© ABB Group
October 29, 2009 | Slide 18

19. LEAP
Standard
© ABB Group
October 29, 2009 | Slide 19

20. LEAP Standard package
100
P o la r iz a tio n -D e p o la r iz a tio n C u r r e n ts
U PHASE DC Measurements
Pol-Depol Currents (microAmp)
10
Polarization De-Polarization
1
Current Analysis
0 .1
1 10 100 1000
T im e (s e c )
C h a r g in g D is c h a r g in g
TAN DELTA MEASUREMENTS
AC Measurements
4.00
3.50
3.00
Non Linear Behavior Analysis
Tan Delta (%)
Tan δ and Capacitance Analysis
2.50
2.00
1.50
1.00
0.50
Partial Discharge Analysis
1 2 3 4 5 6 7 8
Voltage (kV)
U Phase V Phase W Phase UVW Phase
Remark: DC tests are sensitive to the surface
condition, and AC tests give more information on
the insulation volume
© ABB Group
October 29, 2009 | Slide 20

21. DC measurements
Polarization-Depolarization Currents
UVW PHASE
Parameters
100 Derived
Time constants
Pol-D epol C urrents (m icroA m p)
Q1, Q2 10 T1, T2, T3
Charge storage
1
: Q1, Q2, Q3
Q3 Ageing Factor
0.1
Dispersion
Ratio
(1+Q1+Q2+Q3)
0.01
1 10 100 1000 Volume
Time (sec)
Resistivity
Charging Discharging
Remark: Polarization - De-polarization Current Analysis
Conventional IR
& PI Besides leakage and absorption current, PDCA test gives an idea of
Measurements
may have
quantity and location of charge storage within the machine
satisfactory
values even Identifies contamination even when IR, PI values are “acceptable”.
with highly
contaminated Determines state of the winding insulation, ageing, looseness, etc.
windings
© ABB Group
October 29, 2009 | Slide 21

22. AC measurements
INSTANTANEOUS CAPACITANCE VARIATIONS
@ 5.8 kV
CAPACITANCE (Arbitrary Units)
110
65
20
-25
-70
40 42 44 46 48 50 52 54 56 58 60
TIME (msecs)
U - PHASE V - PHASE W - PHASE UVW - PHASE
Non Linear Behavior Analysis, Tan δ and Capacitance Analysis,
Partial Discharge Analysis
Confirm the results from DC Measurements
Assess the condition of Corona protection shield
Determine the extent of de-lamination or void content in terms of a
Remarks: percentage of discharging Air Volume to Insulation Volume
Conventional
measurement Assess condition of the Stress Grading system at slot ends
interpretation
is generally Trend Ageing effects
based on
trends
© ABB Group
October 29, 2009 | Slide 22

23. LEAP
from the Case Book
© ABB Group
October 29, 2009 | Slide 23

24. Contamination indicated by LEAP
IR >>1000
MΩ
PI >> 2
© ABB Group
October 29, 2009 | Slide 24

25. Contamination indicated by LEAP
© ABB Group
October 29, 2009 | Slide 25

26. Slot discharge / wear detected by LEAP
© ABB Group
October 29, 2009 | Slide 26

27. Surface discharge detected by LEAP
© ABB Group
October 29, 2009 | Slide 27

28. Case study 1: LEAP – Maintenance Planning
11MW 11kV 1500 RPM, Synchronous
Motor (Air Separation problem)
Purpose of Testing: The motor was in
operation for 69,000 hours with no outage. LEAP
Standard carried out to determine the need for L3 or
L4 Maintenance. On-line pd alarm had appeared.
Results - PDCA Test
IR- 2310 Meg ohm
PI- 2.02
Q1(%) – 9.63
Q2 (%) – 11.30
Key Findings: Q3 (%) – 44.54
LEAP Standard indicated presence
of oil/carbonized contaminants DR – 1.65 AgF – 60.12
predominantly on the overhangs Vol Res – 1013.78 Ohm-m
Recommendation:
Open the end covers and clean end windings (L3). No immediate need of
overhaul with rotor removal (L4)
Benefits: Optimized Maintenance Planning
© ABB Group
October 29, 2009 | Slide 28

29. Case Study 3: LEAP Maintenance Verification
6034 HP, 6 kV, 502A, 1481rpm
RESULTS - PDCA TEST
Before Overhauling
IR - 2205 Mohm
PI - 4.79
Q1 – 78.68 %
Q1, Q2
Q2 – 65.49 %
Q3 – 128.56 %
Q3 After Overhauling
DR – 3.73
IR - 32464 Mohm
PI – 5.63
Q1 – 7.84 %
Q2 – 8.84 %
Q3 – 8.86 %
DR – 1.25
© ABB Group
October 29, 2009 | Slide 32

30. LEAP – Usage
LEAP for Maintenance Planning
LEAP for L1, L2, L3, L4 inspection
LEAP for Run/Replace/Retrofit
Decisions
Measurements and Analysis are to be
done at a single occasion (L4) with
additional assessment of other
components besides the stator windings
LEAP for Life Extension/ Upgrade
Decisions
© ABB Group
October 29, 2009 | Slide 33

31. Life Improvement
Strength
Stress/Strength
Developed Stress
Years
Improvement in
life by restoring
strength droop
Improvement in life by
upgrading machine
© ABB Group
October 29, 2009 | Slide 34

32. Life Improvement
Strength
Stress/Strength
Developed Stress
Years
Improvement in life by
restoring original stress Improvement in life by
developed reducing stress through
redesign
LEAP for
‘Life Extension’
© ABB Group
October 29, 2009 | Slide 35

33. LEAP – How is it different?
Methodology is not dependent on old records of measurements
performed. Single occasion of measurements will suffice for making
decisions. Parameters are derived from measurements to quantify
problems such as contamination, ageing and looseness.
65-72% of failures are related to Thermal and Ambient reasons which
may not be detected by measurements that rely only on partial
discharges. ABB’s measurements and analysis focuses also on
detection non-partial discharge related problems.
Analysis software is UNIQUE and parameters derived from analysis can
be utilized in Life Expectancy Calculations
Sophisticated FEM analysis can be deployed during L3 and L4
maintenance.
Can be related to time and integrated into a Maintenance Plan
© ABB Group
October 29, 2009 | Slide 36

34. Towards a New Dimension
We change the units !
Machinery status is typically
expressed in vague units
(green, yellow, red)
We change that into a
measurable dimension:
time that can be easily
interpreted by other
computerized systems and
related to scheduling
actions
© ABB Group
October 29, 2009 | Slide 37

35. LEAP - Value for the Customer
Optimizes Maintenance Planning of
Electrical Machines by moving from
Scheduled Maintenance to Condition
Based Maintenance
Life Extension of machines would lead
to increased earnings capability and
thereby greater return on investment.
Facilitate decision making (short and
long term maintenance planning)
Focus mainly on essential maintenance,
and machines that are vulnerable,
thereby reducing downtime at lower risk
levels
Provides important “lifetime ” inputs for
more realistic estimates of Life Cycle
Costing
© ABB Group
October 29, 2009 | Slide 38

36. © ABB Group
October 29, 2009 | Slide 39