CIRED 1999
Session 1: NETWORK COMPONENTS Session 2: POWER QUALITY AND EMC Session 3: SYSTEM MANAGEMENT Session 4: not made available Session 5: SYSTEM DEVELOPMENT Session 6: MANAGEMENT-ORGANIZATION-SKILLS
Session 1
NETWORK COMPONENTS /
COMPOSANTS DU RESEAU
by R. Dides,Chairman, and A. Doulet, Rapporteur (France)
The session was organised around 3 themes including now the subject of aerial lines and cables:
32 reports were selected. They were mainly complements and updates and served as the guidelines for the Special Report which carried 19 questions destined to stimulate both written combinations prepared in advance and spontaneous written and/or oral interventions.
Preferential Subject 1: Equipment Design
The debates were based on 15 author contributions, followed by 2 written contributions prepared in advance, 17 written and 5 spontaneous contributions.
The final half hour was dedicated to the presentation of work by the group of experts linked with session 1, relative to recent and significant evolution of norms applicable to network components.
The following points resulted from the debate:
Preferential Subject 2: Life Cycle of Components
The debates were based on 7 author complements, 2 pre-prepared written contributions and 12 written contributions.
Due to lack of time, no spontaneous contributions were possible.
The following points resulted from the debate:
Preferential Subject 3: Environmental Constraints
The debates were based on 6 author contributions, one pre-prepared written contribution and 12 written contributions. As for theme 2, there were no spontaneous contributions.
The following points resulted from the debate:
Session 2
POWER QUALITY AND EMC /
QUALITE DE LA TENSION ET CEM
by A. Robert, Chairman, and J. Hoeffelman & E. De Jaeger Rapporteurs (Belgium))
Part 1: LF Disturbing Phenomena
Part 2 : Power Quality
Part 3: Electromagnetic compatibility and safety problems
Part 4 : Improving Power Quality and managing Electromagnetic fields
4.1: Improving Power Quality
- Measurement results may not be significant from a statistical point of view so that simulation can help in finding complete descriptions. Simulation can also help in designing mitigation solutions to Power Quality problems.
- It is important to model completely and accurately the protection devices for Power Quality simulation purposes.
- There was no unanimity to declare that simulation results could be used for contractual purposes. The improvements that could be brought to simulation software are related to load modelling and short-circuit computations (large size systems). However, these improvements are not considered as urgent.
- Methodologies need to be set up towards the assessment of the price of "non-quality".
- It is worth for distribution companies to help customers finding solutions to their Power Quality problems. This includes participating to costs evaluations and investigating possible technical solutions, i.e. developing actual partnerships in order to propose customised solutions.
- Although some practical experiences have been mentioned, new technical solutions (power electronics based, e.g. active conditioners) seem to be difficult to launch. More classical solutions are still considered successfully in many cases.
4.2: Electromagnetic fields
- Standards cannot help finding a solution to the influence of magnetic fields on CRT.
- Technical solutions are now well known (shielding, layout of LV cabling…) but are not always cost effective.
- Managing EMF is also a question of communication (with the customers, with the authorities…).
- The lack of international recommendation (due to the absence of established long term health effect) leads to national (regional) regulations that can differ by a factor as high as 500.
SESSION 3
SYSTEM MANAGEMENT /
GESTION DU RESEAU
by F. Otto, Chairman, and B. Ehmcke, Rapporteur (Germany)
For this session on the first day 31 papers as well as 8 poster-sessions contributions from 19 countries have been presented, selected from some 75 papers offered, whereof 3 papers were unfortunately withdrawn.
Essentially 6 different preferential subjects were discussed, covering
As an introduction a summary of the final report of WG 03 - "Fault Management" from December 1998 was presented by Mr. Lehtonen giving an overview about the practise and solutions in 9 different European countries as collected by the working group members for analysis and comparison. This report is available at the CIRED secretary office in Brussels as a valuable information describing principal fault management functions, costs and benefits as well as present and future state of art.
Covering a very special and spectacular network blackout a case review of the summer 1998 Auckland (NZ) incident was given, highlighting the findings from the Government Inquiry and discussing supply security and network planning standards for a central business district. Actual outage costs of 2.5 Euro / KWh were indicated and as most critical situation the high summer peaks from air condition were identified in combination with reduced loading capacity of some 20 and 40 year old cables for 110 kV, which should be monitored carefully.
The other discussions of the first part indicated the following basic requirements for fault management:
Different methods and remote control means, as well as optimising restoration strategies were pointed out for reducing interruption time.
Indications about intermittent earth faults not only in compensated but also in resistance grounded mv cable networks were given with fault statistics of 5.4 faults per 100 km and year resp. 0.4 for intermittent faults.
With respect to the second part on maintenance strategies different contributions commented on the trend towards reduced maintenance and towards reliability centered maintenance, i.e. selecting only the most important and critical elements, making best use of limited resources available by software supported matrix evaluation.
Several contributions of the third part covered the different methods of neutral grounding and the difficulties to identify almost to zero reduced fault currents in resonant grounded systems. Special methods such as using 5. harmonics were pointed out again as one means already implemented, while other new algorithms are being developed in France, indicating the need for additional improvements.
In the fourth part about integrated protection and control the principal advantages as well as considerable reduced communication links and use of glass fiber optics were highlighted. The very important task of standards for interfaces was outlined, where part 1 System Requirement and Architecture as well as part 2 Glossary have been elaborated by WG14 if IEC TC 57 and new work items identified and especially participation of utility engineers is solicited for better incorporation of their specific needs.
In the fifth part about documentation systems (SCADA, GIS etc.) it was pointed out that the introduction of these systems is considered essential, but requires considerable costs often underestimated at the beginning and should especially avoid doubling of work. Installation of new working group was proposed in order to profit from the experiences available of users and manufacturers for new developments, striving for new standards.
The sixth part was concerned with the powerline carrier communication, where it was reported about the successful application in a medium and low voltage network with sufficient quality for remote metering as well as tests for internet connections. Technical challenges are the coupling demands, but the distances covered have to be increased. Agreement on certain frequency ranges is needed and emi-problems could result at the higher end.
Altogether some 60 contributions, including authors updates, prepared written as well as some spontaneous contributions, resulted in an intensive and interesting sequence of discussions during the 4 sections covering the 6 main preferential subjects indicated. The principal efforts concentrate on improving fault management, developing more efficient maintenance strategies, finding the most adequate way of neutral grounding, taking advantage of new integrated protection and control, reducing the costs and looking for the best way to integrate the different documentation systems, and finally also combining information channels with powerlines. This indicates the wide scope covered using a variety of choices available, depending on the special conditions and experiences, leaving upon new topics and subjects for future discussions.
Session 4 : not made available
Session 5.
SYSTEM DEVELOPMENT /
DÉVELOPPEMENT DES RÉSEAUX
by L. Azpiazu (Spain), Chairman, and A. Invernizzi (Italy), Rapporteur
The development of electricity supply systems is nowadays an extremely interesting subject especially because new events like the institutional changes, the liberalisation of electricity market, the integration of new technologies for distribution and generation heavily influences the development, involving also the role itself of distribution networks. The Session regarded all the aforesaid topics by the three proposed preferred subjects and the animated debate explored many aspects pointing out different point of views.
In total 31 reports were included for discussion in the Main Session and other 10 reports, dealing with specific subjects, were included in the Dialogue Session; the discussion was animated by 41 programmed contributions and by several spontaneous contributions that dealt with the content of the various reports included in the Session and answering the questions posed in the Special Report. Finally a lively discussion involved many spontaneous speakers in debating the subject proposed by the Chairman relevant to the role of planners in the new scenario dominated by liberalisation of the electric market.
The more significant considerations stressed in the discussion are hereunder summarised.
Influences of electric market liberalisation and competition on electricity distribution systems and related companies.
The creation of free markets also in the electricity sector and setting up competition among different operators have involved nowadays the Electricity Industry of many countries in restructuring processes aimed at eliminating monopolies. It was pointed out in the discussion that in reality the main function of an electric distribution network is to transport electricity from stations connected to the transmission network and from embedded generation to the electricity delivery points; therefore the main tasks of electric distribution companies should still regard development, operation and maintenance of the electric networks while energy retail and commercialisation of energy or of other services (as in the case of multi-utilities) should be the objective of other companies.
Electricity distribution has the characters of a natural monopolium to be subjected to a careful regulation aimed to pursue reduction in costs, improvement in efficiency and service quality; moreover the regulator has to control that non discriminatory access rights are assured by distribution companies to the electricity end users and to prevent the abuse of market dominant positions.
A main topic of distribution regulation is relevant to the ability to transfer to the tariffs all the utility costs, i.e., remuneration of investments, ohmic losses, service quality improvement, connection fees; the tariffs should also include mechanisms to incentive economic efficiency. Finally, small non-eligible users that cannot negotiate price and service quality level, should be protected by appropriate regulations stating, for example, maximum prices and minimum quality levels.
As regards service quality, the discussion stressed the role of Authorities to identify the appropriate indices and to state the methods for index measurement and processing in order to allow the correct comparisons among the various distribution companies acting in the market.
Embedded Generation
The discussion stressed a wide and lively interest for the subject; dispersed generators are now diffused in the electric distribution systems of many countries, connected to HV, MV and LV networks. While it was recognised the benefits that dispersed generators may provide in term of alleviating network constraints, delaying network reinforcements, participating in the local voltage control, it was also stressed the existence of some drawbacks. The siting of dispersed generators does not depend on network needs but it is strictly related to user necessities and industrial installations; moreover their operation is associated to industrial processes and not to the network loading. It was declared that small generators (lower than 20 MW) may only participate to the tertiary reserve and to the local voltage regulation; studies are in course about the possibility to accept the islanded operation, as an alternative of local black-out, of part of distribution networks where dispersed generators are integrated.
Methods and computer systems for expansion optimisation and operation analysis of distribution networks
Planning of development and operation of electricity distribution systems are a complex and difficult task considering the multiple development alternatives among which to select the optimum ones and the existing uncertainties now increased because of the changes that are in progress in the electricity sector. The development and use of computing systems, that may integrate several different computing functions, as well as GIS, DBMS and friendly use man-machine interfaces were indicated as a mean to reduce costs of study execution and to improve the relevant results.
It was also stressed the need for flexible methods that allow to study and solve the new problems related to the changes now occurring in the electricity sector, able to manage the related growing uncertainties; fuzzy theory, artificial neural networks and genetic algorithms were suggested as possible approaches to solve the aforesaid difficulties.
The role of planners in the new scenario
Spontaneous contributions were provided by many speakers in answering the question posed by the Chairman at the end of the Session. The contributions pointed out different opinions, probably as a consequence of the different models adopted in the various countries in restructuring the electricity sector. The answer to the question may depend on few points:
Recalling the fact that distribution companies and utilities have the duty to develop and expand the electric distribution network covering an area, it should be confirmed that planners have in any case the task to select the optimum expansion alternatives and the relevant investments, by minimising the total costs and assuring adequate levels of security and quality.
by Niels Haase (Denmark),Chairman, ans Kjell B. Mortensen (Norway) Rapporteur
General remarks
The session clearly stated an ongoing rapid change of business climate in the electricity industry around the world. The deregulated utility environment raises new challenges to the electricity distribution companies. This necessitates focusing not only on the technological advances but also on the changing tasks of management. Therefore, in order to compete, the utilities have to put focus on business development and strategy.
The reasons for this change of focus are twofold. Firstly, because the rapid changes in business opportunities and business environment are calling for new organisation structures and new skills both on the strategic level and on the short term operational level. Secondly, because new business opportunities are made possible by technological development.
Examples of this, given in the Session, are the increasing competition and market focus, and new customer services based on information and communication technology, and also new tools and methods to handle the new situation.
The four preferred subjects chosen for this session cover the topics that are considered of greatest interest related to the field of management, organisation and skills.
The session started with the presentation of an invited paper from Norway on the subject: regulation and the consequences of regulation for the network companies. The electricity distributing companies in Norway have been operating under regulation condition since 1991. They have also experienced changes in the regulating regime, which have required additional efforts from the utilities.
Preferred subjec 6.1: Business Goals and Strategies
The distribution utilities experience a great change in business environment due to political decisions both on a global and a national basis, which give new market conditions. The new situation makes it necessary for the distribution industry to reform its business goals and reconsider its strategies. The new market conditions and the third party access to the distribution network give new and great challenges to the distribution companies. The discussion underlined the need for changes and development in business goals and in methods to develop new goals and strategies.
Recognising the need for a new strategy and the ways of implementing the strategy in the organisation is a challenge the electricity industry have to face today. Different views within the company on the situation and the adequate strategy may complicate the situation. Employee commitment for a new strategy is of greatest importance.
Developing new strategic goals is of great importance to the utilities wishing to stay in business in the future. To aid this development, necessary tools are available and different methods of approach are used. Identifying core business and focusing on this part of the company activities are important to succeed.
Actually, the new business situation has affected the business goals of electricity distribution in the different countries. Identifying and defining key-factors to reach efficiency in planning in connection with investment selection and scheduling seems to be of great importance. The same is the case with characteristics connected with product quality.
Preferred subject 6.2: Organisation and Business Structures
The new and coming business environment that the utilities are facing calls for changes and development in organisations and business structures and in methods to develop organisations and structures. Organisation and business structures are closely linked to the use of technical management systems, methods for optimising the use of resources and adequate tools to handle data involved. Also the development of a positive organisational climate created by new kinds of leadership has great influence on the efficiency of an organisation.
Preferred subject 6.3: Human Resource Management and Professional Skills
The new situation the utilities find themselves in will not be handled efficiently without the development of the human resources and their professional skills. To ensure the employees' commitment and the stimulation of their creative ability is an important key to business success.
Preferred subject 6.4: Competitiveness including Reduction of Costs
It was interesting to learn about the new approaches and experiences in improving competitiveness and cost reductions in distribution companies.
The political objective of deregulation and regulatory regimes is reduction of cost to the benefit for both the customers and the owners. Different models to create an incentive for reduction of cost are used. To have the full understanding of the consequences of the different models for cost and quality of the service is a real challenge.
Examples of measures taken to reduce cost and increase profit were given. Optimal investment, maintenance and operation of the network are influenced by many factors ranging from overall systems to sophisticated tools and methods. Such tools and methods are important to promote further development. And in the centre is the satisfaction and trust of the customer.
Tools and methods like Total Quality Management and Business Process Re-engineering are used by the electricity distributing companies to achieve reduced cost and improve competitiveness. These tools have been adequate for the task and they have to some degree given the expected results.
The use of information and communication tools is essential in the electricity distributing industry. Such tools play an important role in promoting competitiveness. As the co-operation between participants in this business develops it seems crucial that the different tools are able to operate together.
