Benef i Cts of Implementing Distribution Automation
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The Benefits
of
Implementing Distribution Automation and System M onitoring
in the Open Electricity Market
Rong-Liang Chen
Member of IEEE
Shafi Sabir
Senior Member of IEEE
Abstract
In the new busine ss environment rates for monopoly distribution services (wires), regulators are trying to
create a balance between the dollars paid by the con sumers and rate of return that the shareh olders are
allowed to earn. The regulator in Ontario has implemented Performance B ased R egulation (PBR) to
regulate the wires part of the distribution system. In PBR quality of services provided to the customers
are considered as one of the performance m easurement criteria. Distribution automation and system
monitoring are the w ays that electric utilities will be able to create innovative ideas for better customer
services, improve reliability, defer capital investment and improve system operation.
The authors describe the impact of deregulation of electricity utilities on electricity rates and conduct
economic analysis to show the benefits of implementing distribution automation and system monitoring in
the distribution system planning and operations. In the recent years more and more S CAD A, IED and fiber
optics are installed in the distribution systems to improve system op eration, customer services and generate
additional revenue.
This paper also describes a planning process for impleme nting distribution automation. The planning process of
distribution automation includes planning strategies, ustification of distribution automation functional projects and
identification of distribution automation projects. The paper emphasizes on the distribution automatic switching and
utilization of integrated comm unication networks.
Key words: distribution automation automatic switching comm unication systems
I INTRODUCTION
The recent regulatory changes have caused emergence of new issues for the utilities in managing the pow er
system and co ncern in retaining the customers.
As
distribution utilities shift from non-profit public utilities to
profit-driven b usiness enterprises, the question how to m aintain and improve service reliability w hile keeping
electricity rates lower and protect shareholders interests becomes more difficult to answer. The trend that service
reliability is going downwards is not uncom mon as seen in some of the utilities. Reliability has a cost and
regulators have to provide incentives to im prove the system reliability.
Besides the chang ing of the utility business, the emergence of new sensitive loads such as e-b usiness data
center, lntemet Service Provider (ISP) and industry with sensitive manufacturing process demanding
uninterrupted and stringent quality of power supply. These new loads not only add on the system peak
demand about 5-13%and grow fast, but also require high standard of service reliability and power
quality.
The evolutionary growth in micropro cessor based devices and telecommunication equipm ent and network have
brought the possibility of integrating protection, control, metering, automation and monitoring system cost
effectively. This will considerably improve system reliability, quality of supply, and customer service and defer
capital investment on system expansion. Distribution automation and system monitoring meet the demands and
requirements in improving service reliability at a lower cost.
In this paper authors will discuss the impact of deregulation on distribution utilities in S ection
11
Distribution
automation and system monitoring and their benefits are shown in S ection 111 Communication system is an
integrated part o f implementing distribution automation and its fun ctions are described in S ection IV. In Section
V the authors show their experience [1] [2] and values in planning distribution automation, especially the
Ca nad ian C on fer enc e on Ele ctrica l an d C om pul er k% &ehg 2001 Toronto
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automatic switching. Techno logy of distribution automa tion is still under developm ent and innovations will make
more benefits to utilities. Section
V
discusse s the most beneficial DA function, automa tic switching. The benefits
and innovation of automatic switching are reported. One of the keys to the success of such project depends on
establishing simple vision with clear goals and objectives. Proper Busin ess Plans and effective Project
Management described briefly in Section V will ensure success
11
IMPACT OF DEREGULATION ON DISTRIBUTION UTILITIES
The main impacts of deregulation on distribution utilities were the procurement of electric power, maintain and
improve service reliability and better customer services. The procurement o f electric power in the short-term and
long-term contracts between the utilities and the power providers is an important factor to ensure lower electricity
rates for customers at all times. In terms of engineering it is substantial to maintain and improve operation
efficiency in the deregulatory environment to provide pow er to customers at acceptable reliability level and to
serve the customer in better ways.
Under new structure of the deregulation the w ire i.e. transmission and distribution system will be regulated and
generation will comp ete in open market. In the past regulators allow ed the distributors to
set
the rates of
electricity based on revenue requirement or cos t of service plus other expenses to be recovered in rates. In the
new business environment rates for monopoly distribution services, regulators are trying to create a balance
between the dollar paid by the consum ers and return-on-investment (R 01) that the shareholders o f the utility are
allowed to eam
[3].
There are different methods that can be considered, such as market based
or
incentive based.
Each one
of
them has different merits and dem erits.
The regulator in Ontario at present chose a water down version of Performance Based Regulation (PBR). In
PBR quality of service provided to the customers is considered as one o f the performance measurement criteria.
The quality of service may include improvement of system reliability, powe r quality, and custom er services, etc.
The regulator will approve just and reasonable rates for transmitting and distributing electricity. Distribution
automation and system monitoring can meet the above quality of service improvement criteria and the cost
justification can be aligned with the corporate objectives o f system performance improvement.
111
DISTRIBUTION AUTOMATION AND SYSTE M MONITORING
1 Distribution Automation
Distribution Automation (DA) can b e defined as automatically monitoring, protecting and
controlling switching operations through intelligent electronic devices to restore power service
during fault by sequential events and m aintain better operating conditions back to norm al
operations. If we add Demand Side Management (D SM ) functions, such as Automatic Meter
Reading AMR) nd Load Managem ent (LM), into distribution automation, it comes a broad
definition of Distribution Automation.
Distribution automation can be divided into three categories, such as transformer substation, feeder,
and customer premises automations. Usually the distribution automation on substation and feeder
are integrated to share comm on monitoring and controlling equipment an d devices.
The DA functions on transformer substation include substation control such as bus voltage control,
circulating current control, bus load balancing and overload control, and transformer protection
such as bus fault isolation, and transformer isolation. The DA functions on feeder mainly include
feeder automatic switching and feeder voltage/Var control. The form er deals with fault
identification, fault location, fault isolation an d service restoration. Th e latter contains capacitor
placement and voltage regulator control. The DA functions on the customer premise could be in a
broad range covering load control, real-time price signaling, remote meter reading and billing, etc.
We have to justify these functions by evaluating their benefits. These benefits are financial,
operational maintenance and customer satisfactions. The financial benefit and the expenses of
operations and maintenance are quantified in dollars. The outcome o f improved operational and
maintenance benefits and custom er satisfaction are not measurable. In order to make these types of
benefits comparable we consider using cu stom er interruption co sts (CIC ) to reflect these benefits,
which include tangible and intangible benefits [4][5]
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2. Benefits of distribution automation
a. Financial benefits
Deferral of capital investment (new TS, additional transformer capacity, additional feeders,
Increased revenue due to quick restoration
Reduced operation and maintenance cost
Improved utilization o f system capacity
Reduced system loss
Custom er retention for improved quality of supply
reconductoring etc)
b. Operational Maintenance benefits
Improved reliability by reducing outage duration
Improved v oltage control
Reduced man hour and man power
Accurate and useful planning and operational datdinformation
Better fault detection and diagnostic analysis
Better management of system and compo nent loading
c. C ustomer related benefits
Better service reliability
Reduce interruption cost for customers
Better quality of supply
3.
System Monitoring
Over the years distribution system monitoring has been improved co nsiderably because of financial
benefits as well as improvement of system reliability. Monitoring system allow s gathering
information of the feeders, transformers [6][7] switchgears, and customer loads during normal
operations as well as faulted conditions. With the advancement of se nsors, high-speed
communication system and the new processors with the high speed processing capability,
tremendous scopes for online and offline diagnostics of system condition an d equipm ent have
emerged, which will ultimately reduce O&M cost and improve asset management. The information
gathered by the monitoring system w ill help to integrate protection and control to improve custom er
service and system performance.
The monitoring system will collect a large number o f valuable information, which will be
processed and stored in a d ata storage facility, and it will be used by different applications. It is
important to plan ahead for the hardware, operating system and database technolo gy to be
employed. Possibly the business information will be integrated into the sam e database and hence
the management of the data will be an important issue to resolve. [8][9]
4. Benefits of System M onitoring
Some utilities have im plemented system to monitor embedded gen erators, transformers, cables,
overhead lines and customers loads, etc. in the distribution system to achieve certain benefits such
as:
Improve operation efficiency
Achieve better reliability
Reduce the risk of failure
of
equipment
Better information on custom ers load profile
Accurate load forecasting
Implement cond ition based maintenance
Less cost in meter reading
Reduced revenue losses due to theft of service
Improve outage reporting
The new information that will be made available by the mon itoring system will encourage
researcher to develop new algorithms and software for protection control, distribution
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automation, diagnostics, etc. which will ultimately reduce O&M cost. The information will also be
very useful for system planner, system operators and for preparing cost effective maintenance
schedule. There are numerous possibilities and they will increase our productivity, improve asset
management, improve distribution system availability and will help to earn customer loyalty.
IV. COMMUNICATION SYSTEM
A communication system is an integral part of the Distribution Automation and M onitoring System. In the new
business environment it is becoming more important to bring information from the field devices for faster
processing and making a quick decision. Th e wireless legacy sy stem that most of the distribution utilities have
operated at 800 and 900 MH z band an d numbe r of channel allocated for distribution automation are very limited.
These legacy systems are not suitable for applications for next generation of automation and monitoring system.
The legacy systems are inadequate but their services and investment will be m aintained for a while and at the
same time future network needs to be built ready for the next generation of automation and m onitoring system.
Before utilities decide to invest for future comm itment of com munication network, utility should establish the
necessary strategic performance and financial objectives. One o f the strategic performance objectives could be
to create broader o r more attractive product line and superior customer services and one o f the financial
performance objectives could be to create a diversified revenue base.
Electric utilities can cost effectively build a fiber optic network within its service area because they own the
poles and ducts. Utilities could play a major role in building the futu re all optical networks, wh ich will provide
service to the bandwidth hungry customers. [lO] [ll][ 12][13] Utilities will need sm all portions of the fiber
capacity for its own use but the rest of the capacity can be leased to a third party r with a partnership with
telecom company being able to provide bandwidth services. The utility network will be a hybrid fiber-wireless
network. The wireless network will be mainly used for communicating w ith the field devices including meters
and field crews. The future network should be a single converged voice and data network, which will integrate
utilities busines s information system , billing, custome r service, and voice and field applications. Issues related to
protocols
[
14][ 151 and network management should be addressed at the planning stage of the project. Som e
utilities are alternatively considering internet-based technology.
V.
AUTOMATIC SWITCHING BEING MOST
BENEFICIAL
Automatic switching is
a
sequential process in restoring power supply when feeder faults occurred
causing power interruption. The sequential process of power restoration include s fault identification,
fault location, automatic fault isolation (sectionalization) and service restoration.
All
of the four
functions can be accom plished by installing intelligent automatic switches equipped with som e
communication devices.
Through the benefit analysis to the functions o f distribution automation, the most beneficial function is
automatic switching, which has been im plemented by man y utilities successfully by investing millions of
dollars with a rate o f retum o f about 2.5 3 years. The benefits are due to the capability of the automatic
switches that can isolate the faulted feeder section and restore power service
to
the unfaulted feeder
sections within one minute o f time starting at the time when the fault occurred. It reduces outage time
from an average of 60 90 minutes down to less than one minute. The analysis shows that automatic
switching will saved about 2.00 of customer interruption cost (C IC) per one kVA connected load.
For
two typical feeders of 30 kVA connected load there will be a saving o f 60,000 o f CIC a year. It was
estimated that the custom er minutes caused by customer load interruption would be reduced by about
25
for the overall system. There are also savings in operation cost such a s crew fault inspection,
manual operations of switching. Moreover, it mitigates the dam age to the feeder equipment and extends
the equipment life cycle by reducing the nu mbe r of inrush current caused by closing feeder breakers to
locate the fault.
To maximize the benefits of automatic sw itching and minimize the capital costs of automatic switches it
is important to determine the minimal num ber
of
automatic switches installed in the feeders and the best
effective locations to install the automatic sw itches. This is an example that now utilities are seeking
technology-based solutions to achieve greater benefits to satisfy customers.
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VI. BUSINESS PLANNING PROJECT MANAGEMENT
Distribution automation and system m onitoring are major projects and require considerable investment. A
proper business plan for the project is essential because it will help to make a decision in its entirety. Each
organization has a general business planning and de cision making process w hich is based on certain criteria that
should be followed in developing the business plan. Som e of the major items that need to be included in a
business plan are as follows:
The corporate business and financial strategies and objectives
Regulatory issues
Project descriptions
Business and technology drivers
Tangible and the intangible values and benefits
Investment costs o f the project
O& M costs
Training costs
Project prioritization process in the o rganization
Time table of the project
Financial analysis including rate
of
return
Risk analysis
One of the difficulties the business planner faces at the time of developing business plan is the methodology to
be used in compu ting the cost-benefit ratio. Some of the methodologies used by the authors are based on
customer interruption cost (CIC)
[4][5],
nalytical hierarchy process (AHP ) [161and resource-allocation
decisions
[
171
A proper project management process should be in place to manage such projects. The process will include
planning, scheduling, allocation of resources, monitoring an d controlling [181 The process will be designed to
manage organization's resources to com plete the project within time, w ithin cost, within expected performance
and customer's satisfaction. Also the risk management a nd scope change controlling processes should be
integrated in the project managem ent process.
The implementation o f distribution automation and s ystem mo nitoring along with the supporting
communication system go hand in hand. Th e strategies/business plan to implement the above systems
should not consider the s hort term benefits only, but also the long-term benefits. Utility should also
think of implementing the above s ystems at the same time b ecause the individual system complements
each other and the total benefits per dollar of inv estment will be m ore than if they are done separately.
If quality of system performance and customer services is some of the corporate objectives to meet
regulators' performan ce criteria then the above systems shou ld be one o f the strategic initiatives for the
utility. In the new wire business environment it is important to implement the above systems for the
benefits of the organization, imp roving custom er services, generating additional revenue, providing
us ef d inform ation for operating and planning decision makin g and better asset management etc.
V11. CONCLUSION
This paper discusses the various benefits of distribution system automation and system m onitoring to
improve system operation, system reliability, asset managem ent, etc. Because of the present competitive
business environm ent and new sensitive loads customers are dem anding greater reliability and quality of
service. The new SCA DA, IED and communication systems make it possible to integrate protection,
control and monitoring together to its maximu m benefits. The innovative development of automatic
switching will yield more benefits to distribution utilities. Truly, distribution automation and system
monitoring are the logical choice for the utilities to improv e system performance, and to achieve
customers and shareholders satisfactions.
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References
[51
R.L. Chen, S. Sabir and K. Allen, Applications of Value-Based D istribution R eliability S tudy and
its Applications presented at the CE A Engineering Operations Conference, Montreal, March
1993 and included in CE A E Transactions 1993.
R.L. Chen,
K.
Allen and R. B illinton, The Value-Based Distribution Reliability Assessment and
Planning, IEEE Transaction on Po wer Delivery, Vol. 10, pp.421- 429, January 1995.
Earl Hazan, Reliability Help Hostage, Transmission Distribution World, Vol 53, No. 1,
January 2001.
R. Billinton and L G oel, Electrical Service Reliability Worth Evaluation in Power S ystem s,
Presented at the Engineering Operations Meeting, Canadian Electrical Association, Vancouver,
March 1992.
Power System Research Group, Assessment
of
Reliability Worth in Electric Pow er System in
Canada, Report to the Natural Sciences and Engineering Research Council (NSER C), University
of S askatchewan, June 1993.
K.T. Yoon and D.S.A. Teo, Controlling and Monitoring Singapores Underground Grid, IEE E Com puter
Applications in Power, October 1999.
Jame s L. Kirtley, Wayne H. Hagman, B emar d C. Lesieutre, Mary jane Boyd, E. Paul W arren, Hsiu P Chou
and Richard D. Tabors, Monitoring the Health of Power Transformers, IEE E Com puter Applications in
Power, January 1996.
Douglas Proudfoot and Dave Taylor, How to Turn a Substation into a Database Server, Computer
Applications in Power, April 1999.
David Becker, Herb Falk, John Gillerman, Steve Mauser, Robin Podmore and Leila Schneberger,
Standards-based Approach Integrates Utility Applications, IEEE Co mpu ter Applications in Power,
October 2000.
Michael Perz, SON ET-B ased System Enhances Reliability, Transmission Distribution World, Vol. 52,
No. 10, O ctober 2000.
S.
Sabir and H. Mahoney, Building a Backbone for Integrated Business Communications, IEEE
Computer Applications in Power, Jan 1996.
Mik e Whitten and Rich Maxwell, Memp his Network- A public-Private Partnership, Transmission
Distribution W orld, Vol. 52, No.
8
Aug 2000.
Ahmed A .A. Adas, Optical Nets Integrate Control Over Global Grids, IEEE C omp uter Applications in
Power, October 1998.
Ron W. Bijoch, Adopting a Standard: How ICCP Wo rks for Northem States Power, Transmission
Distribution W orld, Vol.
50,
No.
12, Dec. 1998.
Mark Adamiak and William Premerlani, Data Communications in a Deregulated Environment, IEEE
Computer Applications in Power, July 1999.
Thomas L. Satty and Luis G . Vargas,
The Logic of Priorities
(book on AHP application) RWS
Publications, Pittsburgh.
Paul Sharpe and Tom Keelin, How Sm ithkline Beecham Mak es Better Resource-Allocation Decisions,
Havard Busines s Review, March-April 1998.
Harold Kerzner,
ProjectManagement
A
Systems Approach to Planning Scheduling and Controlling
Seventh Edition, John Wiley Sons , Inc.
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