Upload
wayne-neal
View
14
Download
1
Tags:
Embed Size (px)
DESCRIPTION
Barcelona, May 13, 2003 ASSET MANAGEMENT Development of new approaches Gerd Balzer Darmstadt University of Technology. TU Darmstadt Institute of Electrical Power Systems. Overview. -Introduction -Age profile of equipment -Consequence of the ageing process - PowerPoint PPT Presentation
Citation preview
Barcelona, May 13, 2003
ASSET MANAGEMENTDevelopment of new approaches
Gerd BalzerDarmstadt University of Technology
TU Darmstadt Institute of Electrical Power Systems
Overview
- Introduction
- Age profile of equipment
- Consequence of the ageing process
- Maintenance strategies
- Reliability-Centered Maintenance (RCM)
- Example: Assessment of substations
- Renovation strategy with Fuzzy-Logic
- Proposal for a Risk-Assessment
- Conclusion
TU Darmstadt Institute of Electrical Power Systems
TU Darmstadt Institute of Electrical Power Systems
Component level
System level
Corporate level
1:Maintenance and diagnostic evaluationscenario search and evaluation ofeffectiveness & usability
2:Economical evaluation of scenarios,creation of maintenance strategies,calculation of non-availability of energy
3:Risk management,selection of optimal scenario,and optimal strategy
Technicalinformation(on assets)
Economical information(on assets)Technical information(on grid)
Economical information(on business)Sociological information
Decision
Asset Management decision process (Cigre WG 23/39)
Age distribution for m.v. equipment(VDEW-statistic, Germany)
TU Darmstadt Institute of Electrical Power Systems
0.00E+00
2.50E+05
5.00E+05
7.50E+05
1.00E+06
1.25E+06
1.50E+06
1.75E+06
2.00E+06
19
58
19
60
19
62
19
64
19
66
19
68
19
70
19
72
19
74
19
76
19
78
19
80
19
82
19
84
19
86
19
88
19
90
19
92
19
94
19
96
19
98
TR VT CBLD CT Bay
Year of installation
Po
pu
lati
on
Age distribution for substations (AIS)(Cigre Brochure no. 176)
0100020003000400050006000700080009000
10000
0-5 10 15 20 25 30 35 40 45 50 55 60 65Age in 1998 (Years)
Po
pu
lati
on
Gas CB Oil CB Air CB Bay Assets Transformers Indoor GIS E/mech Prot
Range of Asset Life Estimates
TU Darmstadt Institute of Electrical Power Systems
Installations and replacement distribution(substation equipment, Cigre Brochure no. 176)
Installation Replacement
TU Darmstadt Institute of Electrical Power Systems
Consequence of ageing
Falling reliability of the system is a majorconsequence of the ageing process:
- decision to delay asset replacement- an attempt to recover by increasing asset
replacement at a later stage
Lower availability and further fault outages
TU Darmstadt Institute of Electrical Power Systems
The spiral of decline
Delayedreplacement leads
to
move inservicefaults
leadsto
longerrepair outages
leadsto
loweravailability
leadsto
leadsto
leadsto
cancelledplanned
work
even morefaults
Attempt torecover
leadsto
leadsto
leadsto
loss ofsupply
by
morereplacement
loweravailability
whilststill in a
period ofhigh unreliability
more doublecircuit events
CONTINUALLYFALLING
AVAILABILITY ANDRELIABILITY
TU Darmstadt Institute of Electrical Power Systems
In general the Reliability Centered Maintenance (RCM) strategy for substation can be used in two different ways:
- substation approach: Which equipment/components influence the function of the
complete substation (Failure Mode Effect Analysis, FMEA)
- system approach: Which substations influence the availability and the performance of the system (reliability calculation and assessment of the non-delivered energy, risk management)
The report deals with the system approach
TU Darmstadt Institute of Electrical Power Systems
The system approach solves the main task of an utility, due to the financial constraints and to receive a ranking of substations concerning the yearly budget:
which substation has to be maintained first, second, and so on.
TU Darmstadt Institute of Electrical Power Systems
Different types of maintenance strategies
Condition-based
Reliability-centered
Time-based Corrective
TU Darmstadt Institute of Electrical Power Systems
Corrective or Reactive Maintenance
- repair or replacement after a fault
- no influence on the time of failure
- availability of the substation depends on the reliability of the single equipment
- lowest maintenance costs without consideration of further expense
TU Darmstadt Institute of Electrical Power Systems
Time-Based or Scheduled Maintenance
- predefined inspections (time period)
- replacement after a fixed life time
- high availability
- no use of the equipment up to the end ofthe life time
- most expensive maintenance strategy
TU Darmstadt Institute of Electrical Power Systems
Condition-Based or Predictive Maintenance
- inspection or replacement due to thecondition
- all identical equipment are treated in the
same manner
TU Darmstadt Institute of Electrical Power Systems
Reliability-Centered Maintenance
- inspection or replacement due to the technical condition
- importance of the equipment for thenetwork
- optimal maintenance strategy
TU Darmstadt Institute of Electrical Power Systems
Maintenance Strategies
CMCorrective
Maintenance
yesno?
Maintenance activitiesfor specific
types of equipment
?no yes
diagnostic
CBMConditionBased
Maintenance
TBMTimeBased
Maintenance
yesno?
RCMReliabilityCentered
Maintenance
importance
TU Darmstadt Institute of Electrical Power Systems
Procedure for maintenance planning (equipment)
Index ccondition of equipment
Index iimportance of equipment
Maintenancestrategy
Index ooverall indexof equipment
TU Darmstadt Institute of Electrical Power Systems
Procedure for maintenance planning (substation)
Index iimportance of
substation
Index iimportance of
substation
Index ooverall indexof substation
Index ccondition
of substation
Circuit-breaker
DisconnectorBay Building
Protection & Control
TU Darmstadt Institute of Electrical Power Systems
Interpretation of the assessment resultc condition of the equipmenti importance of the equipment
TU Darmstadt Institute of Electrical Power Systems
Condition based maintenancec condition of the equipmenti importance of the equipment
TU Darmstadt Institute of Electrical Power Systems
Replacement
maintenance work
inspections
Corrective, time-based or reliability centered maintenancec condition of the equipment i importance of the equipment
TU Darmstadt Institute of Electrical Power Systems
inspections maintenance work
replacement
Combination of different strategiesc condition of the equipmenti importance of the equipment
TU Darmstadt Institute of Electrical Power Systems
Assessment of 40 secondary substations
TU Darmstadt Institute of Electrical Power Systems
21 6/10 kV
19 30 kV
(four tower stations)
Equipment of the substations
TU Darmstadt Institute of Electrical Power Systems
- bay/type of construction
- disconnector
- load disconnector
- transformer
- building/tower
condition criteria for theassessment of bays
- age; type
- experiences; spare parts
- safety aspects
- partial discharge
- pollution; humidity
TU Darmstadt Institute of Electrical Power Systems
TU Darmstadt Institute of Electrical Power Systems
Impact of equipment evaluationg the condition assessment in percentage
0
10
20
30
40
50
60
70
HE
IS-
10
1
NE
NN
-3
22
PO
HL
-3
01
GL
AS
-8
01
HO
HA
-3
04
bays disconnector transformer buildingC
on
dit
ion
/%
Importance criteria for the assessment of secondary substations
- kind of substation
- maximum active power
- customer
- redundancy of the substation
- hazard rate
TU Darmstadt Institute of Electrical Power Systems
0
20
40
60
80
100
0 10 20 30 40 50 60 70 80 90 100
c
i
EHSN-307SHAF-299
POHL-301
HOHA-601
TU Darmstadt Institute of Electrical Power Systems
importance
con
dit
ion
Final result of the assessment
replacementA
BC
d
dA
dB
dC service
TU Darmstadt Institute of Electrical Power Systems
Basic principle of a decision-taking process using fuzzy logic
Rules
Fuzzification DefuzzificationKnowledgeprocessing
Input valuesOutput values
TU Darmstadt Institute of Electrical Power Systems
Implementation of a maintenance strategy for substations
TU Darmstadt Institute of Electrical Power Systems
Secondary substation
condition 3: load/disconnector condition 1: bay
Conditon 3 Conditon 1
resu
lt
TU Darmstadt Institute of Electrical Power Systems
Time after commissioning resp.
service
Propability of outage of equipment Non delivered
energy
Result of reliability calculation
Equipment model
Outage costs
Interruption costs- repair- interuption of supply - penalty and so on
Risk-Management
Szenario:- no action- service- renovation
“sociological effects”
Risk Assessment
Maintenance costs- service- renovation
TU Darmstadt Institute of Electrical Power Systems
Equipment model
time after commissioning/last servive
haz
ard
rat
e
T2T1 T3 T4
2
1
4
I IIIII
TU Darmstadt Institute of Electrical Power Systems
time after commissioning/last service
pro
ba
bil
ity
of
ou
tag
es
Probability of outages of the considered equipment
0.0
0.2
0.4
0.6
0.8
1.0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
T T +t
Tdt)t(f
tT
Tdt)t(f
TU Darmstadt Institute of Electrical Power Systems
Probability of outages of the considered equipment
Pro
bab
ilit
y o
f o
uta
ges
time after commissioning/last service
Q
Qb
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
Result of the assessment (substation):
- comparison of different substations
- determination, which equipment influences mainly the condition of the substation
- what is the optimal order of substation to be maintained or replaced
Decision: replacement of the equipment or newinvestment of the complete substation
TU Darmstadt Institute of Electrical Power Systems
Advantage of a computer aided assessment:
- fixing of compulsory criteria
- determination of the ranking due to replacementor ranking
- documentation of the decision
TU Darmstadt Institute of Electrical Power Systems