IEC TR 62195:2000

TECHNICAL IEC
REPORT
TR 62195
First edition
2000-04
Power system control and associated
communications –
Deregulated energy market communications
Conduite des systèmes de puissance
et communications associées –
Communications dans un marché d'énergie déréglementé

Reference number
IEC/TR 62195:2000(E)
Numbering
As from 1 January 1997 all IEC publications are issued with a designation in the
60000 series.
Consolidated publications
Consolidated versions of some IEC publications including amendments are

available. For example, edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the
base publication, the base publication incorporating amendment 1 and the base

publication incorporating amendments 1 and 2.

Validity of this publication
The technical content of IEC publications is kept under constant review by the IEC,
thus ensuring that the content reflects current technology.
Information relating to the date of the reconfirmation of the publication is available
in the IEC catalogue.
Information on the subjects under consideration and work in progress undertaken
by the technical committee which has prepared this publication, as well as the list
of publications issued, is to be found at the following IEC sources:
• IEC web site*
•
Catalogue of IEC publications
Published yearly with regular updates
(On-line catalogue)*
• IEC Bulletin
Available both at the IEC web site* and as a printed periodical
Terminology, graphical and letter symbols
For general terminology, readers are referred to IEC 60050: International
Electrotechnical Vocabulary (IEV).
For graphical symbols, and letter symbols and signs approved by the IEC for
general use, readers are referred to publications IEC 60027: Letter symbols to be
used in electrical technology, IEC 60417: Graphical symbols for use on equipment.
Index, survey and compilation of the single sheets and IEC 60617: Graphical symbols
for diagrams.
* See web site address on title page.

TECHNICAL IEC
REPORT
TR 62195
First edition
2000-04
Power system control and associated
communications –
Deregulated energy market communications
Conduite des systèmes de puissance
et communications associées –
Communications dans un marché d'énergie déréglementé

 IEC 2000  Copyright - all rights reserved
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International Electrotechnical Commission
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– 2 – TR 62195  IEC:2000(E)
CONTENTS
Page
FOREWORD . 3

Clause
1 Introduction. 4

1.1 Task defined by TC 57 . 4

1.2 Background. 4
1.3 Quadrant diagram . 6
2 Transactions (quadrants 1and 3) . 6
2.1 Market transactions (quadrant 1) . 8
2.2 Technical transactions (quadrant 3). 9
2.3 Interface between market and technical information system (quadrant 1/3) . 9
3 Available protocols . 10
3.1 Protocols available for market transactions (quadrant 2). 10
3.2 Protocols available for technical transactions (quadrant 4). 11
4 Need for standards and work programme . 14
4.1 Market transaction and protocols (quadrants 1 and 2). 14
4.2 Technical transactions and protocols (quadrant 3 and 4) . 15
4.3 Transactions between market and power system operation. 16
4.4 Proposal . 17
5 Conclusions . 18
Annex A Comparison of markets and related transactions . 20
Annex B Definitions . 25
Annex C Existing solutions. 29
Annex D An actual example for figure 1 model (market in England and Wales). 35

TR 62195  IEC:2000(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
POWER SYSTEM CONTROL AND ASSOCIATED COMMUNICATIONS –

DEREGULATED ENERGY MARKET COMMUNICATIONS

FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, the IEC publishes International Standards. Their preparation is
entrusted to technical committees; any IEC National Committee interested in the subject dealt with may
participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. The IEC collaborates closely with the International Organization
for Standardization (ISO) in accordance with conditions determined by agreement between the two
organizations.
2) The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an
international consensus of opinion on the relevant subjects since each technical committee has representation
from all interested National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this technical report may be the subject of
patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
Technical reports do not necessarily have to be reviewed until the data they provide are
considered to be no longer valid or useful by the maintenance team.
IEC 62195, which is a technical report, has been prepared by technical committee 57: Power

system control and associated communications
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
57/434/Q 57/457/RQ
Full information on the voting for the approval of this technical report can be found in the report
on voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 3.
This document which is purely informative is not to be regarded as an International Standard.

– 4 – TR 62195  IEC:2000(E)
POWER SYSTEM CONTROL AND ASSOCIATED COMMUNICATIONS –

DEREGULATED ENERGY MARKET COMMUNICATIONS

0 Scope
This technical report deals with electronic communication in deregulated markets.

0.1 Reference documents
IEC 61334 (all parts) Distribution automation using distribution line carrier systems
IEC 60870-6 (series) Telecontrol equipment and systems – Part 6: Telecontrol protocols
compatible with ISO standards and ITU-T recommendations
1 Introduction
1.1 Task defined by TC 57
The task of the AHWG05 is to identify requirements and functional needs for communications
in deregulated markets. In so doing, a clear distinction should be made between
communications for control of energy systems and communications for the market. On the
other hand, the interrelation and interworking between these separate fields have to be
addressed.
The subject should include, but not be restricted to, the ‘transport capacity market’, the ‘energy
spotmarket’, ‘bilateral trades’, ‘accounting and billing’ and general communication services
such as electronic mail.
For the next TC 57 session (Lucerne) a report should be prepared including a proposal for a
scope and a work programme.
In response to concerns on the objectives of this ad hoc group the following statement was
also made:
The goal of the ad hoc working group is not (yet) to elaborate a standard, but to analyse
whether and where a standard should be elaborated. It is not the intention of TC 57 to become
involved in political issues nor to advise utilities how to organize the competition in the
electricity market.’
1.2 Background
There had been some preliminary discussions on electricity trading within the UNIPEDE
NORMICT group, particularly concerning trading across borders. This issue was subsequently
raised at the TC 57 Plenary in Dresden in September 1996 where it was decided that, if there is
need for standardization of communication protocols concerned with deregulated electricity
markets, then this would fall within the scope of TC 57. A meeting was called at Dresden to
discuss how to proceed and a possible scope. The response was greater than expected, but no
conclusion was reached regarding scope. The Plenary then decided to create AHWG05 to
study the matter.
AHWG05 has since studied existing and proposed solutions to deregulation in order to learn
what the requirements should be. In this respect the initial approach has been ‘bottom up’. In
addition, the group has further refined its scope.

TR 62195  IEC:2000(E) – 5 –
- trading energy
- generation of energy
- trading system services
- providing system services
- reservation of transmission capacity
- providing security and stability

- billing and accounting
Producer
Broker/
Generating
depending on
market model
Trader
units
Market result
Other
Power
Control
information required
Exchange
Control
for security
Consumer Center
Center
Distribution
information required
Single
by market
Cont. Center
Buyer
Pow.Op.Sys. result :
substations
Regulator
. . .
yes/no
Power operation
system
Market system
rather wellknown and stable
Diverse, complex, evolving
depends on physics
depends on regional politics
Figure 1 – Market system and power operation system
Firstly, a distinction has to be made between market and power operation communication
systems. Figure 1 shows the main characteristics of these two worlds and their interfaces. Of
course, the actors (boxes) and transactions (lines) have to be taken as an illustration and not
as a reliable description of reality, that is far more complex.
The left-to-right arrows represent the information provided by the market to the power
operation. One arrow (coloured in plain grey) is determined by regional organization (grid code,

market organization, etc.). The other arrow (coloured in shaded grey) is the information the
market has to provide to the ISO(Independent System Operators) in order to secure power
system operation.
The right to left arrows represent the information provided to the market by power operation.
The colouring code is similar to the above, but the first arrow provides data which depends on
regional organization (metering, etc.) and the second that which is necessary for security.
An actual example of this model, representing the system in England and Wales, is given in
annex D.
– 6 – TR 62195  IEC:2000(E)
1.3 Quadrant diagram
The following diagram (figure 2) completes the former by a second classification: transactions

and protocols. That leads to the structure with four quadrants:

Quadrant 1: Market information system (market applications and actors and transactions

between them)
Quadrant 2: Available protocols for market transactions.

Quadrant 3: Technical information system (power system operation applications

transactions)
Quadrant 4: Available protocols for technical transactions
COMMERCIAL TECHNICAL
T
Q3
R Q1
A
N
MARKET RESULTS
S
market technical
A
C
T applications applications
I
Power operation
O
N system result
S
Q4
Q2
P
T
T
R
A
A
O
WWW
T
S S
O
. . .
EDIFACT
E
E
C
O
. . .
L
S 2
Figure 2 – Quadrant diagram
2 Transactions (quadrants 1and 3)
In deregulated energy markets, the notion of transaction model is important. This includes the
actors, the transactions itself and the exchanged objects involved. With deregulation the
transaction effort increases significantly in respect to integrated utilities because there are
more interfaces between now independent functions and actors. It should be the aim of any
standardization to decrease the transaction effort by use of advanced ICT (Information and
Communication Technology). There are many examples of other markets that make extensive
use of ICT. This report deals only with electronic communication interfaces. Standardization of
these interfaces for more than one market would make these tools cheaper and new markets
would benefit from the experiences of more advanced markets.
Transactions are basically split in this report into market transactions and technical (process)
transactions. The process produces products as energy, transmission capacity with associated
transmission schedule (firm or not firm) and interconnected system operation services
(community services: generation and demand balance, transmission security, emergency
preparedness, individual services: real power losses, energy imbalances, backup supply, load
following) for the market. One-time integrated products of integrated utilities are now de-
bundled into separate products and so billing and accounting becomes an issue from the
reading of the meters, collection of accounting data, settlement of accounts to the bill. In some
market models (UK) competition has been introduced into the supply and reading of meters.

TR 62195  IEC:2000(E) – 7 –
Accounting becomes even more complicated because energy exchanges in deregulated
markets become third party (customer) driven and may cross multiple control areas affording a

whole chain of settlement of accounts (transactions are paid on the basis of contracts and

differences between scheduled transactions and physical delivery).

Each market has its own regulatory framework to ensure non-discriminatory open access of

end customers/load aggregators/generators/traders/etc., to the network to allow free trading of

energy. The task of the process in full deregulated markets is limited to implementing the

schedules decided by the market (generation and transmission) and to provide interconnected

system operation services, and security and stability of system operation according to the laws

of physics with paid and predefined quality of products.

In deregulated markets, many actors have two faces and therefore appear on the process side
as well as on the market side. On the process side, the actors are concerned with the
production process and on the market side with offering and trading of the products. Some of
these products such as generation and demand balance, for example, cannot be traded and
are mandatory for the functioning of the power system. On the other hand, ‘end customers’, i.e.
those who finally consume the energy, only appear on the market side.
Because in full deregulated markets, the market decides who is contracted to deliver how much
and to whom, and also the price, the ‘interface between market and process’ mainly deals with
giving the market decision (trading of energy, capacity, optional services) to the process and
getting the answer of the process if the market decision can be put into operation. The answer
in most cases can be simply ‘yes or no’, but it can also be associated with additional
information such as system constraints and curtailments. Then it becomes clear that many
traditional transactions such as scheduling of energy generation (self-committed generators)
and scheduling of energy transmission (third-party driven) move to the market side and control
the process, whereas the process side implements it physically or makes it possible. Within the
market process, it is not simply a question as to whether the supply can match the demand;
there is the possibility of an iterative loop where demand is altered depending on the cost of
supply.
The actors of full deregulated markets are Power Exchange (PX, bidding of generation and
load), Traders/Brokers, System Operators Transport and System Operators Distribution,
Independent System Operators (ISO) separated legally from Generation and Transport
Providers, Security Co-ordinators (see USA), Transmission Providers (‘wires’), Generation
Providers, Distribution Providers (‘wires’), Suppliers (purchasing and selling energy to
distribution customers) and End Customers of both transport and distribution. The definition
and naming of actors as well the interaction between them may be different in different markets
and depends, besides logic, also on politics, history, regulation, experience and culture. To
make it even more complicated, deregulated markets never are established overnight and
develop in course of time by experience. So some markets have a history of 10 and more years
of deregulation development.
One characteristic of these evolving market structures is the movement of responsibility for
certain activities from the ”technical” to the ”commercial” domain (from quadrant 3 to quadrant
1), which makes any future model very sensitive to market factors. The boundary between
quadrants 1 and 3 depends heavily on the market structure and requires specific consideration
and more detail for standardization. Some markets (current state of OASIS/TIS in USA)
implemented a simple customer interface ignoring the rules of physics (contract path) and are
changing now to a more sophisticated mapping of the market to the process (parallel power
flow analysis computed by power distribution factors applied to so called flowgates) to reconcile
the market with the process.
It is also important to note the level of transactions is related only to the number of active
traders and the frequency of trading. However, on the continental scale, the market transaction
effort is greater in markets with high load, large population and industrial density and
geographical size if these markets are based on multiple energy systems (control areas or
zones with balancing generation and load) sometimes with a hierarchical control structure.

– 8 – TR 62195  IEC:2000(E)
A first inventory of transactions and their implementation in observed or projected deregulated

energy markets is given by annex A. The aim was to give a first comparison of different

markets. Please note that this inventory is probably not comprehensive, and that names may

have different meanings from one market to another (see definitions in annex B).

2.1 Market transactions (quadrant 1)

This subclause addresses transactions within the commercial market environment, instead of

the technical and engineering environment covered by quadrant 3. Transactions in quadrant 1
are based on two broad classes of market structure models:

physical bilateral contract model, and

power exchange for spot energy and ancillary services.
Most markets mix both structures. The EU models TPA (Third Party Access) / NTPA
(Negotiated Third Party Access) and Single Buyer both belong, in respect to the results, to the
physical bilateral contract model, whereas the Electricity Pool of England and Wales in the UK
is a Power Pool model with power exchange (load forecast instead of load bidding). The open
access rules of FERC in the USA are like TPA. Besides this, pure financial markets for futures
(price hedging) exist which are out of the scope of this report. The same is true for so called
contracts of differences.
The following examples of market transactions, which may not be complete, are given from
observed markets.
(1) Market transactions of Physical Bilateral contracts are:
Contracting generation and auxiliary services (deals on paper)
Transmission capacity market
• Offer of transmission capacity
• Reservation of transmission capacity
• Splitting and aggregation of transmission capacity
• Re-sale of transmission capacity
• Accounting and billing
(2) Market transactions of Power Exchange are:
Power Exchange (both energy and auxiliary services)

• Bidding of generation and demand
• Result of bidding
• Settlement of accounts
• Billing and accounting of traded energy services
or
Power Pool
• Bidding of generation and forecast of demand
• Result of bidding (price)
• Settlement of accounts
• Billing and accounting of traded energy

TR 62195  IEC:2000(E) – 9 –
2.2 Technical transactions (quadrant 3)

Technical transactions are exchanged between ‘technical actors’ (i.e. control centres,

generation units, substations, etc.) for power system real time operation. It is assumed that

‘real time’ represents ‘what is concerned with power system on line operation’. That might

include some provisional information (e.g. short term production schedules) and a posterior
data (post mortem archives, realized load curve, historic protection relays operation, etc.).

As an example, the following technical transactions frequently happen in power system
operation:
• status signals and events (switching device positions, transformer tap changer positions,

protection relays events, alarms, etc.) transmitted from substations to control centres;
• measurements (voltage, active power and reactive power, current, primary reserve, etc.)
and counter values transmitted from substations and generation units to control centres;
• inter control centre communication within a utility and between interconnection utilities
(topology, measurements of tie lines, counter values, energy transmission schedules
between control zones, operator messages);
• area or local switch commands (breakers, transformer tap changers, load shedding
equipment, etc.) from control centres to substations;
• instructions (set point commands) from control centres to generation units;
• power generation schedules (P = f(t)) from control centres to generation units (this is not
true for self-committed generators, see 2.3);
• unit commitment from control centres to generation units (this is not true for self-committed
generators, see 2.3);
• exchange of information on transmission schedules between control centres;
• .
Process information is also exchanged between the transport network and transport network
customers (end customers, generators, distribution networks) for the security of power system
operation. These transactions are part of the technical information system.
2.3 Interface between market and technical information system (quadrant 1/3)
In addition to what is used today power system operators in deregulated markets will need
additional information to cope with bilateral trade and power exchanges in the TPA (open third
party access to the network) environment. Note that the actors of the process have two faces
and here only the interface between the market and technical information systems is described.
The observation of deregulated electricity markets shows some general trends:

a) By spot market or bilateral trade, the market gives to the process a first draft of schedules
(‘who produces, where, when, for whom, how much over time’), with or without reservation of
transmission capacity. Examples are:
Energy transmission scheduling
• Request of transmission schedule
• After reservation of transmission capacity
• Without reservation of transmission capacity (all-in-one)
• Confirmation of transmission schedule
• Meter readings
• Settlement of accounts
• Billing and accounting
– 10 – TR 62195  IEC:2000(E)
Generation schedules
• Aggregated schedules for system operator

• Meter readings
• Settlement of accounts
• Billing and accounting.
• .
b) The final decision to implement the schedules is up to the system operators after

transmission capacity and security analysis. In case of network constraints, counter purchasing

of production and splitting of markets can be done either by the ISO, any other operational
authority, or the market itself. As an example, this information could be:
• Simply ‘yes’ or ‘no’
• Notifications of constraints by the system operator, curtailments in case of disturbed
operations
• Information on subsequent operational requirements that may have an effect on the market
in terms of costs
• Actual operation costs
• .
3 Available protocols
This clause covers 'available' protocols. In this context 'available' is taken to mean a protocol
which is either already being used in support of deregulated energy market communications, or
is suitably defined as a 'paper' specification, preferably as a published standard.
3.1 Protocols available for market transactions (quadrant 2)
3.1.1 EDIFACT
EDIFACT is a standard created by the UN for exchanging structured data. UN/EDIFACT is
being recognized as the single international standard for EDI. In document SB3/13/INF, IEC
Sector Board 3 endorses this and makes recommendations to formalize this.
In Scandinavia, EDIEL is now the standard for Electronic Data Interchange for the ELectricity
Market trading. The aim was to reduce the use of fax and manual interfaces. EDIEL makes use
of the existing EDIFACT standard, which is structured like a table of data elements. The first
implementation used X.400 messaging over X.25 channels. It has also been implemented over
ISDN and TCP/IP. EDIEL can easily adapt to the SMTP protocol and Internet instead of X.400

and X.25.
EDIEL is implemented over both public and private networks and links all market participants
with non real-time communications associated with the market. It is used for transactions such
as bidding, billing and exchange of production schedules (next day) but not for more immediate
operations such as secondary regulation which is done by telephone. Information providers
also have access for the provision of bulletin boards (Dow Jones, Reuters, etc.) of energy
prices.
3.1.2 WWW
WWW is a world-wide used Internet technology with a great future including commercial
applications. Security and performance are critical issues and should be taken into account.
WWW is a client / server technology and uses HTML, FTP, JAVA applets and e-mail. For
clients, cheap or free browsers can be used which run on every PC providing a graphical user
interface. WWW has no standardized message formats for applications (to be individually
standardized).
TR 62195  IEC:2000(E) – 11 –
In the US, open transmission access is mandated by the Federal Energy Regulatory

Commission (FERC) government and implemented via OASIS (Open Access Same Time

Information System), which began operation in 1997 for Phase 1. Technical specifications for

OASIS are based on recommendations from the industry and formally adopted by FERC in

Standards and Communication Protocols for Open Access Same Time Information System

(OASIS). OASIS allows the reservation of transmission capacity and the booking of auxiliary

services. This is done by standardized messages based on HTML templates. NERC intends to
use WWW also for the future TIS (Transaction Information System) to allow transmission
scheduling subsequent to capacity reservation with OASIS. WWW will also be used for the

customer interface of the PX in California.

3.1.3 Protocols used in the UK deregulated market

Domestic electricity competition began on 14 September, 1998. Prior to that, the electronic
Data Transfer Network had been operating for more than one year. During the majority of this
time, it carried testing information, although the difference between data flows which carry a
test flag and those which carry an operational flag is not material to the service. In the
transitional period until June 1999, when full competition was introduced, the service carried
both live data and test information for those market participants who had not yet qualified to
open their markets. Whilst the data Transfer Network has a major role in the collection of
metering data, it is not restricted to that. The service applies between all players in the
industry. A large number of data flows have been defined between players and these are then
carried by the Data Transfer Service. The Principal Users of the service are the settlement
agencies (the Electricity Pool and the Scottish Settlements Organisation, suppliers including
the Public Electricity Suppliers and the second tier entrants, data aggregators, etc.)
In the first phase of implementation of the DTN bids, schedules, operational data, ancillary
services, charging and pool boundary metering remain with the existing system and initially so
will remote metering of ‘second tier’ suppliers (i.e. those operating on another companies
network) supplying customers above 100 kW peak demand. However, the collection of both
MOST (Metering Outside Settlement Timescales) and MIST (Metering Inside Settlement
Timescales) Settlement data for customer below 100 kW peak demand are a function of the
new network. This links the agent of the ‘Pool’ in the guise of ISRA (Initial Settlement
Reconciliation Agent) with all market participants which include distribution companies, the
transmission grid operator (NGC), the grid operator of vertically integrated companies
(Scotland), supply companies, data collectors (half-hourly and non half-hourly), data
aggregators (half-hourly and non half-hourly), meter operators (half-hourly and non half-hourly),
PES Registration Service Agents and the MPAS (Metering Point Administration Service).
Since at the time when this report was originally written, the Data Transfer Network was not in
service for live data, and little detailed information was available, it did not fit the definition of
‘available’ in clause 3 above and therefore was not considered in further detail in this report.
However, the information in the above paragraphs has been updated to reflect the current
position.
3.2 Protocols available for technical transactions (quadrant 4)
Protocols already in use include ICCP and ELCOM 90. These are realized in TASE.2 and
TASE.1 respectively and form part of the IEC 60870-6 series of standards. Further information
is given below.
DLMS forms part of the IEC 61334 series of standards. Although originally intended for
distribution automation, the interest has shifted to its use for metering communications
although it has yet to be used on a commercial scale.

– 12 – TR 62195  IEC:2000(E)
3.2.1 TASE.2 / ICCP
TASE.2 is primarily for providing real-time control of the network between control centres. Its

use is therefore not intended to be for electricity market trading, but to be used as a direct

consequence of market trading.

MMS (Manufacturing Messaging Specification) is used for real-time control in the factory

environment. In 1990, work began on TASE.2 by standardizing the Inter-Control Center

Protocol (ICCP), which is based on MMS. The UCA 2 and possible IEC substation bus is also

based on MMS.
TASE.2 is for real-time control between Control Centres, including the scheduling of power flow
between control areas and the state of circuit breakers at the end of tie lines in the remote
station. It also can be used for communication between Control Centres and substations/power
plants. It forms part of the Utility Communications Architecture Version 2 (UCA 2) which has
been sponsored by EPRI and has now become an IEEE report.
In general, factory networks operate at higher speeds than control centres communications
which typically use event oriented transmission. In order to meet these requirements, TASE.2
uses a subset of MMS but adds extra services and object modelling. The most fundamental
change is grouping which defines certain data sets for information transfer. There are different
modes for transferring groups of measurands. For example, one mode may transmit a whole
group if one measurand changes, whereas another may only transmit those in the group which
have changed.
TASE.2 uses client server technology. There is no status update, but all values can be scanned
periodically (5 s) and the time interval can be changed, for example, to 10 s by changing a
parameter. TASE.2 also features access rights and firewall security. The main advantages are
its scaleability, flexibility and use of proven technology (MMS). Also there is no limit to the
number of object definitions, which are independent of the communication protocol. Scheduling
objects can be represented as a table (like a spreadsheet format) and TASE.2 can use this to
put market decisions into action in real-time.
3.2.2 TASE.1 / ELCOM 90
At present, there are ELCOM-90 software systems running or under installation at close to 400
control centres, substations and energy measurement centres in 22 countries.
The ELCOM-90 service specification complies with the services and application programming
interface specified by IEC 60870-6-501 (TASE.1 services). The impetus for the development of
ELCOM/TASE.1 was the need for communication of energy management in an energy market
with application software from different manufactures.

Software for transfer of market information based on EDIFACT with ELCOM-90 as
communication provider is implemented. In addition to the installations mentioned above
ELCOM is also integrated in systems for gas distribution and railway control systems.
The strategy of IEC expressed in IEC 60870-6-501 and IEC 60870-6-502 supports a smooth
transition from the present situation to a situation with a complete OSI stack. Utilities worldwide
have made up their strategy relying on the IEC strategy. Utilities have however been reluctant
to introduce a complete OSI-stack as specified in the IEC 60870-6 series.
An implementation of TASE.1 running on different platforms and with a complete ISO-stack
was presented as a result from a project of several vendors in January 1995 at an IEC TC 57
WG07 meeting.
TR 62195  IEC:2000(E) – 13 –
3.2.3 DLMS
DLMS is related to MMS in having the same concepts as regards the main objects, but

describes fewer services (22, of which only four are obligatory), and is therefore a ‘light’ form of

MMS. It also adds important attributes to manage access rights to objects in terms of a ‘virtual

association’ object, and the rules for operation of objects have been widely simplified. For
instance, DLMS does not enable objects to be created dynamically, which reduces the memory

requirement in equipment.
Although based on the same principles as MMS, DLMS is therefore simple enough to be used

for low cost applications (e.g. metering, demand side management, etc.).

DLMS is independent of all layers below, and of the communications medium used, i.e.
although it began as part of a DLC-based communication specification, it can be (and has
been) implemented in systems using other media. For this reason, it is now referred to as
‘Device Language Message Specification’ rather than ‘Distribution Line’.
DLMS defines a ‘virtual system’, i.e. a system in which the behaviour of the devices involved in
the exchange of data is standardized and defined irrespective of practical implementations. It is
then for a manufacturer ultimately to translate this defined behaviour into a real piece of
equipment, which will then be interoperable with any other manufacturer’s similar equipment
implemented to the same system. The ‘virtual equipment’ included in this system (meters,
concentrators, remote terminal units, protective relays, etc.) contain resources (e.g. data or
other elements) related to its application, which are known as ‘objects’, i.e. abstract entities
with specific characteristics. Each object type has available to it a set of services, and is
defined by attributes, describing their features. The most common object is the ‘variable’, a
variable being defined as ‘one or more data elements that are referred all together by a single
name’. Examples of real items that can be referenced and coded as variables are: tariff
registers, serial number, status of a rate switch, etc. Another object is the ‘task’ which controls
the communications transfer process.
DLMS assumes that the behaviour of every DA/CA equipment can be modelled with these two
types of objects. The strict separation between the objects and the access services allows the
manufacturer to design his equipment freely by using the building stones (objects) of DLMS.
There is an initiative to define metering objects through the DLMS User Association.
3.2.4 Other standards
Other IEC standards which may be relevant to deregulated energy market communications are:
IEC 60870-5-101:1995, Telecontrol equipment and systems – Part 5: Transmission protocols

Section 101: Companion standard for basic telecontrol tasks
IEC 60870-5-102:1996, Telecontrol equipment and systems – Part 5: Transmission protocols –
Section 102: Companion standard for the transmission of integrated totals in electric power
systems.
IEC 60870-5-104, Telecontrol equipment and systems – Part 5-104: Transmission protocols –
Network access for IEC 870-5-101 using standard transport profiles

To be published.
– 14 – TR 62195  IEC:2000(E)
4 Need for standards and work programme

This clause examines the need for standards in each of the quadrants and for the interface

between quadrants and, where applicable, suggests a work programme.

4.1 Market transaction and protocols (quadrants 1 and 2)

Quadrant 1
This quadrant holds the definition of information to be exchanged for commercial operation of
the electricity market and is setting the requirements and characteristics for protocols in
quadrant 2.
The models of information and transactions in quadrant 1 also complete the base standard
protocol products so that a higher level of interoperability between systems can be reached. An
example is EDIEL. Standardization in both quadrants is necessary not only for the sake of
interoperability but also for the 'openness' of the market: any external party should be able to
join the market place without having to implement a complete new communication
infrastructure for every market it wants to enter.
Regarding quadrant 1, the situation is such that international standardization of information
models is at this moment an unrealistic objective. Energy markets all over the world are either
not defined in detail, not yet stable or very different from each other. Intercontinental trading is
not foreseen.
So there is no task for IEC TC 57 in this area at this moment.
There will be an increased demand for transport of data and information within and between
interconnected systems. It could therefore be very worthwhile to define regional standards for
international markets. The example of this case in Europe is the Scandinavian market that
uses the EDIEL information infrastructure. If work has to be done on a regional level is a
market decision: when utilities and/or manufacturers feel the need for standardization in this
area, they can address the appropriate bodies. For example UCPTE or UNIPEDE could could
set the requirements and take an initiative and address CEN/CENELEC to do this work.
Market driven regional initiatives will also increase the speed of standardization compared with
an international approach.
Quadrant 2
In quadrant 2 there are existing and already used base standards (EDIEL in Scandinavia based
on EDIFACT, OASIS and TIS in the USA based on the WWW) that are not ISO/IEC standards
at the moment. The use of base standards is recommended. Use depends on the type of

transaction. For some transactions EDIFACT as well WWW can be used, for others only
EDIFACT or WWW should be used.
EDIFACT is
• recommended by IEC SB3 to be used for electronic commerce;
• already standardized in some degree in regard of standard message formats;
• already used with success for certain types of market transactions (EDIEL).
A standard made available for the industry or a recommendation to use a common
EDI-standard will be an asset for the market process. For settlement of accounts, accounting
and billing and perhaps collecting of metering data there is no alternative standard to EDIFACT
and EDIFACT is therefore recommended. The EDIEL solution also provides a communication
interface for power exchanges (see Nord Pool) based on EDIFACT, which may be used in
other markets. Up to now EDIEL provides no means for transmission scheduling which,
according to the EU directive, is needed for TPA/NTPA but it could be extended for this.

TR 62195  IEC:2000(E) – 15 –
WWW is
• an Internet technology used world-wide with great acceptance and a great future

• messages can be formatted as HTML text templates (to be standardized)

• a cheap graphical user interface is already available (browser).

Applications of WWW in the USA are OASIS for offer and reservation of transmission capacity

and, in the future, TIS for transmission scheduling (MW over hours). Because of its graphical

user interface the WWW can also be used for general information exchange between

customers and utilities.
EDIFACT, and to some extent for certain transactions WWW, are the recommended base
standards for message layout and transaction definitions for commercial transactions in the
electricity market.
As soon as preliminary studies on national market definitions provide more detailed require-
ments and the situation is stable enough, then, firstly on a regional level and possibly on an
international level, the final choice for the basic standard and the standardization of the
information models can take place. Again this is a market decision: regional bodies could
express the need and formulate the objective of standardization work to be done.
4.2 Technical transactions and protocols (quadrant 3
...