Benchmarking of reliability indices for electricity distribution utilities: approach and discussion

2011 ◽  
Author(s):  
Y.K. Bichpuriya ◽  
P.V. Navalkar ◽  
S.A. Soman
Keyword(s):  
Electricity Distribution ◽  
Reliability Indices

scholarly journals Stochastic Planning and Operational Constraint Assessment of System-Customer Power Supply Risks in Electricity Distribution Networks

2021 ◽  
Vol 13 (17) ◽  
pp. 9579
Author(s):  
Mikka Kisuule ◽  
Ignacio Hernando-Gil ◽  
Jonathan Serugunda ◽  
Jane Namaganda-Kiyimba ◽  
Mike Brian Ndawula
Keyword(s):  
Sequential Monte Carlo ◽  
Network Reliability ◽  
Distribution Network ◽  
Integrated Approach ◽  
Distribution Networks ◽  
Test System ◽  
Electricity Distribution ◽  
Reliability Indices ◽  
Operational Constraints ◽  
The Impact

Electricity-distribution network operators face several operational constraints in the provision of safe and reliable power given that investments for network area reinforcement must be commensurate with improvements in network reliability. This paper provides an integrated approach for assessing the impact of different operational constraints on distribution-network reliability by incorporating component lifetime models, time-varying component failure rates, as well as the monetary cost of customer interruptions in an all-inclusive probabilistic methodology that applies a time-sequential Monte Carlo simulation. A test distribution network based on the Roy Billinton test system was modelled to investigate the system performance when overloading limits are exceeded as well as when preventive maintenance is performed. Standard reliability indices measuring the frequency and duration of interruptions and the energy not supplied were complemented with a novel monetary reliability index. The comprehensive assessment includes not only average indices but also their probability distributions to adequately describe the risk of customer interruptions. Results demonstrate the effectiveness of this holistic approach, as the impacts of operational decisions are assessed from both reliability and monetary perspectives. This informs network planning decisions through optimum investments and consideration of customer outage costs.

scholarly journals Economic Analysis for Replacement of 11kV overhead Koteshwor Feeder by Underground Distribution System

2021 ◽  
Vol 6 ◽  
pp. 33-41
Author(s):  
Ganesh Kumar Sah ◽  
Laxman Poudel
Keyword(s):  
Economic Analysis ◽  
Cost Estimation ◽  
Distribution System ◽  
Public Safety ◽  
Distribution Systems ◽  
Cost Effective ◽  
Electricity Distribution ◽  
Reliability Indices ◽  
Standard Data ◽  
Present Worth

Cost effective, Aesthetic and Reliable energy supply is the need of any mankind. In this study, economic analysis for replacement of 11 kV overhead distribution feeder by 11kV underground cable is done with reference to Koteshwor Feeder under Baneshwor Distribution and Consumers Service. The reliability indices like SAIDI, SAIFI, ENS etc. is performed by using DigSilentPowerFactory software. The reliability of overhead distribution system is evaluated by using real system data system and similarly, historical IEEE standard data is used for underground distribution system. The reliability indices are compared for both distribution systems. Result shows that interruption in the overhead system is more than underground distribution system, the energy not supplied to the customer by overhead distribution system is also more than underground distribution system. The replacement cost estimation is performed by using Nepal Electricity Authority (NEA) unit rate and KEI industries quoted price for NEA underground project. The B/C ratio and Present Worth value for the 25-year period of useful life shows that the replacement of the existing overhead distribution system by underground distribution system is financial suitable and can be payback by revenue save from the Energy Not Supply (ENS) lower value of underground distribution system than overhead distribution system. In order to get the continuous of supply, esthetic and public safety in electricity distribution field one may have to bear initially extra cost to use underground distribution systems which finally get payback. Thus, in case of densely populated city like Kathmandu, underground distribution system is reasonable requirement for continuous supply, esthetic and public safety in electricity distribution filed.

scholarly journals Stochastic Planning and Operational Constraint Assessment of System-Customer Power Supply Risks in Electricity Distribution Networks

2021 ◽  
Author(s):  
Mikka Kisuule ◽  
Ignacio Hernando-Gil ◽  
Jonathan Serugunda ◽  
Jane Namaganda-Kiyimba ◽  
Mike Brian Ndawula
Keyword(s):  
Sequential Monte Carlo ◽  
Network Reliability ◽  
Distribution Network ◽  
Integrated Approach ◽  
Distribution Networks ◽  
Test System ◽  
Electricity Distribution ◽  
Reliability Indices ◽  
Operational Constraints ◽  
The Impact

Electricity distribution network operators face several operational constraints in the provision of safe and reliable power given that investments for network area reinforcement must be commensurate with improvements in network reliability. This paper provides an integrated approach for assessing the impact of different operational constraints on distribution network reliability by incorporating component lifetime models, time-varying component failure rates as well as the monetary cost of customer interruptions in an all-inclusive probabilistic methodology that applies a time-sequential Monte Carlo simulation. A test distribution network based on the Roy Billinton test system is modelled to investigate the system performance when overloading limits are exceeded as well as when preventive maintenance is performed. Standard reliability indices measuring the frequency and duration of interruptions, and the energy not supplied are complemented with a novel monetary reliability index. The comprehensive assessment includes not only average indices but also their probability distributions to adequately describe the risk of customer interruptions. Results demonstrate the effectiveness of this holistic approach as the impacts of operational decisions are assessed from both reliability and monetary perspectives. This informs network planning decisions through optimum investments and consideration of customer outage costs.

Assessing Stressors Related to Migration in Patients With Psychiatric Disorders

2012 ◽  
Vol 28 (4) ◽  
pp. 262-269 ◽  
Author(s):  
Matthias Johannes Müller ◽  
Suzan Kamcili-Kubach ◽  
Songül Strassheim ◽  
Eckhardt Koch
Keyword(s):  
Interrater Reliability ◽  
Item Analysis ◽  
Global Assessment Of Functioning ◽  
Family Conflicts ◽  
Response Options ◽  
Reliability Indices ◽  
Dsm Iv ◽  
Functional Relevance ◽  
Sum Scores ◽  
Gaf Scores

A 10-item instrument for the assessment of probable migration-related stressors was developed based on previous work (MIGSTR10) and interrater reliability was tested in a chart review study. The MIGSTR10 and nine nonspecific stressors of the DSM-IV Axis IV (DSMSTR9) were put into a questionnaire format with categorical and dimensional response options. Charts of 100 inpatients (50 Turkish migrants [MIG], 50 native German patients [CON]) with affective or anxiety disorder were reviewed by three independent raters and MIGSTR10, DSMSTR9, and Global Assessment of Functioning scale (GAF) scores were obtained. Interrater reliability indices (ICC) of items and sum scores were calculated. The prevalence of single migration-related stressors in MIG ranged from 15% to 100% (CON 0–92%). All items of the MIGSTR10 (ICC 0.58–0.92) and the DSMSTR9 (ICC 0.56–0.96) reached high to very high interrater agreement (p < .0005). The item analysis of the MIGSTR10 revealed sufficient internal consistency (Cronbach’s α = 0.68/0.69) and only one item (“family conflicts”) without substantial correlation with the remaining scale. Correlation analyses showed a significant overlap of dimensional MIGSTR10 scores (r² = 0.25; p < .01) and DSMSTR9 scores (r² = 9%; p < .05) with GAF scores in MIG indicating functional relevance. MIGSTR10 is considered a feasible, economic, and reliable instrument for the assessment of stressors potentially related to migration.

ASSESSMENT OF ANATOMICAL & FUNCTIONAL SUCCESS IN EXTERNAL DACRYOCYSTORHINOSTOMY BY AIR BUBBLE TEST

2019 ◽  
Vol 3 (9) ◽  
Author(s):  
Dr. Vikas Tantuway
Keyword(s):  
Case Series ◽  
Invasive Procedure ◽  
Nasolacrimal Duct ◽  
Good Tool ◽  
Predictive Values ◽  
Reliability Indices ◽  
Air Bubble ◽  
Bubble Test ◽  
External Dacryocystorhinostomy ◽  
Anatomical Success

Aim: To assess reliability indices of Air Bubble Test (ABT) for anatomical and functional success in external Dacryocystorhinostomy (DCR). Methods: Prospective case series of nasolacrimal duct obstruction underwent DCR. Functional success defined as Munk score 0 & 1 & anatomical success as free irrigation at followup.ABT performed by putting antibiotic drops into eye& asking patient to exhale while keeping nose & mouth closed. Formation of bubbles at punctum considered as positive test. Specificity, sensitivity, positive & negative predictive values calculated. Results: There were 103 DCR in 97 patients(23 male,74 female)with mean age 45.56 yr. Anatomical and functional success was 99.02% & 98.05%, respectively.ABT showed sensitivity 96.07%, specificity 100% for anatomical success after DCR. Sensitivity and specificity were 97.02% & 100% for functional success. Conclusion: As non-invasive procedure ABT is a good tool to assess success of DCR, though lacrimal syringing remains the gold standard. Keywords: Anatomical, Dacryocystorhinostomy & Air Bubble Test.

Sign in / Sign up

Export Citation Format

Share Document