Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
On Risk Management of Electrical Distribution Systems and the Impact of Regulations
KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.ORCID iD: 0000-0001-6882-3642
2008 (English)Licentiate thesis, comprehensive summary (Other scientific)
Abstract [en]

The Swedish electricity market was de-regulated in 1996, followed by new laws and a new regulation applied to the natural monopolies of electrical distribution systems (EDS). These circumstances have motivated distribution systems operators (DSOs) to introduce more comprehensive analysis methods. The laws, the regulation and additional incentives have been investigated within this work and results from this study can be valuable when developing risk methods or other quantitative methods applied to EDS. This tendency is not unique for Sweden, the results from a comparative study of customer outage compensation laws between Sweden and UK is for example included.

As a part of investigating these incentives, studies of the Swedish regulation of customer network tariffs have been performed which provide valuable learning when developing regulation models in different countries. The Swedish regulatory model, referred to as the Network Performance Assessment Model (NPAM), was created for one of the first de-regulated electricity markets in the world and has a unique and novel approach. For the first time, an overall presentation of the NPAM has been performed including description of the underlying theory as a part of this work. However, the model has been met by difficulties and the future usage of the model is uncertain. Furthermore, the robustness of the NPAM has been evaluated in two studies with the main conclusion that the NPAM is sensitive toward small variations in input data. Results from these studies are explained theoretically investigating algorithms of the NPAM.

A pre-study of a project on developing international test systems is presented and this ongoing project aims to be a useful input when developing risk methods. An application study is included with the approach to systematically describe the overall risk management process at a DSO including an evaluation and ideas of future developments. The main objective is to support DSOs in the development of risk management, and to give academic reference material to utilize industry experience. An idea of a risk management classification has been concluded from this application study. The study provides an input to the final objective of a quantitative risk method.

Place, publisher, year, edition, pages
Stockholm: KTH , 2008. , vii, 60 p.
Series
Trita-EE, ISSN 1653-5146 ; 2008:023
Keyword [en]
Electrical Distribution System, Maintenance Management, Project Planning, Regulation, Reliability Analysis, Reliability Centred Maintenance (RCM), Reliability Centered Asset Management (RCAM), Risk Analysis, Risk Management, Risk Methods, the Network Performance Assessment Model (NPAM)
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
URN: urn:nbn:se:kth:diva-4717ISBN: 978-91-7178-954-9 (print)OAI: oai:DiVA.org:kth-4717DiVA: diva2:13598
Presentation
2008-05-15, H1, Teknikringen 33, Teknikringen 33, Stockholm, 14:00
Opponent
Supervisors
Note
QC 20101125Available from: 2008-04-30 Created: 2008-04-30 Last updated: 2010-11-25Bibliographically approved
List of papers
1. Review of the Risk Management at a Distribution System Operator
Open this publication in new window or tab >>Review of the Risk Management at a Distribution System Operator
2008 (English)In: 2008 10TH INTERNATIONAL CONFERENCE ON PROBABILISTIC METHODS APPLIED TO POWER SYSTEMS, IEEE , 2008, 90-97 p.Conference paper, Published paper (Refereed)
Abstract [en]

Sweden was re-regulated in 1996 followed by new laws and regulations. These new circumstances have become incentives to adopt more comprehensive and quantitative analysis methods applied on Electrical Distribution Systems (EDS). This paper provides a systematic presentation of the current risk management at a Distribution System Operator (DSO) as an integrated part of the net planning process. The description is complemented by an example and an evaluation including ideas of future developments. Furthermore, the paper gives a definition on the risk concept; investigates how different incentives affect the risk management; describes and discusses similarities and differences between voltage levels. The main objective is to support DSOs in the work of developing risk management and to give academic reference material to utilize industry experience.

Place, publisher, year, edition, pages
IEEE, 2008
Keyword
Distribution System, Maintenance Management, Project Planning, Regulation, Reliability Analysis, Risk Analysis, Risk Management, Risk Methods
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-8307 (URN)000271680900013 ()2-s2.0-70349122518 (Scopus ID)978-1-934325-21-6 (ISBN)
Conference
10th International Conference on Probabilistic Methods Applied to Power Systems, Rincon, PR, MAY 25-29, 2008
Note
QC 20101125Available from: 2012-02-03 Created: 2008-04-30 Last updated: 2012-02-03Bibliographically approved
2. Investigation of the robustness of the Swedish network performance assessment model
Open this publication in new window or tab >>Investigation of the robustness of the Swedish network performance assessment model
2008 (English)In: IEEE Transactions on Power Systems, ISSN 0885-8950, Vol. 23, no 2, 773-780 p.Article in journal (Refereed) Published
Abstract [en]

The Swedish energy agency (STEM) has developed a regulatory model to supervise the revenues of the distribution system operators (DSO). The model is referred to as the network performance assessment model (NPAM). The NPAM calculates customer values for a fictive electrical distribution system, with a total cost referred to as the network performance assessment (NPA). The debiting rate for a DSO is defined by the quotient of the revenue and the NPA. If the debiting rate is higher than a certain value, the DSO is placed under review and could be forced to pay back revenue to customers. A lawsuit is currently in progress on this use of the NPAM. This paper shows results from a comprehensive sensitiveness study of the NPAM investigating the robustness of the model. The investigation shows that the model is not robust, since small stochastic variations in input data could lead to larger differences in the results than those from the model. For example, it is shown that a five-meter difference in the coordinates of the nodes in the reference system could result in a difference of 5 million Euros, i.e., approximately US $6.5 million. The understanding of weaknesses in the NPAM presented in this paper provides an important means for future developments of regulatory models in the world.

Place, publisher, year, edition, pages
IEEE, 2008
Keyword
customer value, electrical distribution system, network performance, assessment model (NPAM), outage cost, performance-based regulation, probability, redundancy, reference networks, regulatory model, robustness and reliability
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-17785 (URN)10.1109/tpwrs.2008.919247 (DOI)000258765900057 ()2-s2.0-43849108726 (Scopus ID)
Note
© 2008 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. QC 20100525Available from: 2012-01-27 Created: 2010-08-05 Last updated: 2012-01-27Bibliographically approved
3. Review of the Swedish Network Performance Assessment Model
Open this publication in new window or tab >>Review of the Swedish Network Performance Assessment Model
2008 (English)Report (Other academic)
Abstract [en]

The Swedish energy agency (STEM), has developed a new regulatory model to supervise the revenues of the Distribution System Operators (DSO), referred to as the Network Performance Assessment Model (NPAM). The fundamental idea of the NPAM is that the electrical distribution system provides customer values, and the DSO is allowed to collect revenue corresponding to these values. The NPAM calculates customer values for a fictive electrical distribution system, with a total cost referred to as the Network Performance Assessment (NPA). The allowed debiting rate for a DSO is defined by the quotient of the revenue and the NPA. If the debiting rate is higher than a certain value, defined by the Energy Market Inspection (EMI) at STEM, the DSO is placed under review and could be forced to pay back revenue to customers. A lawsuit is currently in progress on this use of the NPAM, which has highlighted drawbacks in the model. This paper provides a comprehensive presentation of the NPAM. It describes in detail the different input data for the model, the steps in the calculations and the resulting cost factors. The paper also presents for the first time details on the theory underlying the calculations.

Publisher
9 p.
Keyword
Electrical Distribution System, Regulatory model, Network Performance Assessment Model, NPAM, Customer value, Outage cost, Probability, Performance-based regulation, Redundancy, Reference networks, Monte Carlo simulation and Reliability
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-8309 (URN)
Note
QC 20101125 This paper was included in a licentiate thesis, but later rejected. A later version of this paper is accepted: http://kth.diva-portal.org/smash/record.jsf?parentRecord=diva2:433030&pid=diva2:415658 (inluded in a PhD thesis) Available from: 2011-08-24 Created: 2008-04-30 Last updated: 2011-08-24Bibliographically approved
4. A Sensitivity Study of the Swedish Network Performance Assessment Model Investigating the Effects of Changes in Input Data
Open this publication in new window or tab >>A Sensitivity Study of the Swedish Network Performance Assessment Model Investigating the Effects of Changes in Input Data
2007 (English)In: 19th International Conference on Electricity Distribution (CIRED), CIRED , 2007, 1-4 p.Conference paper, Published paper (Other academic)
Abstract [en]

This paper present results from a sensitivity study of the Network Performance Assessment Model (NPAM) as an effect of changes in input data. The NPAM estimates a cost corresponding to operate a fictive reference network, so called network performance assessment (NPA). This value is then compared with the revenue. Small changes have been implemented at the customer data level for real electrical distribution systems e.g. moving a low-voltage customer a few meters. Results show on that the NPA could differ up to 7 million Euros. The main conclusion is that a small divergence in input data could result in significant differences in the output data from the NPAM.

Place, publisher, year, edition, pages
CIRED, 2007
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-8310 (URN)
Conference
19th International Conference on Electricity Distribution, Vienna, 21-24 May 2007
Note
QC 20101125Available from: 2012-02-03 Created: 2008-04-30 Last updated: 2012-02-03Bibliographically approved
5. A Comparative Study of Regulation Policies for Interruption of Supply of Electrical Distribution Systems in Sweden and UK
Open this publication in new window or tab >>A Comparative Study of Regulation Policies for Interruption of Supply of Electrical Distribution Systems in Sweden and UK
2007 (English)In: 19th International Conference on Electricity Distribution (CIRED), CIRED , 2007, 1-4 p.Conference paper, Published paper (Other academic)
Abstract [en]

This paper presents a comparative study of regulating policies for interruption of supply in Sweden and UK. The two regulating regimes have been applied for a case study with a real rural electrical distribution system in Sweden, Flymen. The Swedish and UK regulations state that the distribution system operators (DSO) should restore power delivery to customers within 12 and 18 hours respectively for normal weather conditions. If this could not be fulfilled the DSOs are opposed to different predetermined penalty payments to the customers.

In a comparative case study of Flymen the Swedish model (GL) gives a 68% higher compensation to customers than the UK model (GS) for a 30 hours interruption of supply during normal weather conditions. Historical interruption data for the same system gives a 75% higher compensation with the Swedish model (GL) than the UK model (GS). The main conclusion from the comparative study is that the Swedish GL model provides a higher compensation for interruptions of supply to customers than the UK GS model.

Place, publisher, year, edition, pages
CIRED, 2007
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-8311 (URN)
Conference
19th International Conference on Electricity Distribution, Vienna, 21-24 May 2007
Note
QC 20101125Available from: 2012-02-03 Created: 2008-04-30 Last updated: 2012-02-03Bibliographically approved

Open Access in DiVA

fulltext(355 kB)1964 downloads
File information
File name FULLTEXT01.pdfFile size 355 kBChecksum MD5
f55d5eab39f75a05dd74587640191521abed86e32b0eaa89ecf1679c277c9a82f6de6538
Type fulltextMimetype application/pdf

Authority records BETA

Wallnerström, Carl Johan

Search in DiVA

By author/editor
Wallnerström, Carl Johan
By organisation
Electromagnetic Engineering
Other Electrical Engineering, Electronic Engineering, Information Engineering

Search outside of DiVA

GoogleGoogle Scholar
Total: 1964 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 832 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf