Wednesday, April 29, 2009

Industrial Plants - Easier Integration of Automation and Electrical Systems

Usually the automation of production processes (DCS - Distributed Control System) and the electrical distribution system in an industrial plant are two - more or less - independent systems. The electric energy is a very crucial raw material that needs be taken into account in the automation system of the production process.

ABB has focused on this integration during last week's Hanover Industrial Fair (HMI, Hanover Germany) pointing to IEC 61850 as an universal integration standard:

Excerpt from the news letter: "... What has been standard in the sector of power generation and supply is now also coming to effect in the process automation sector. The international standard IEC 61850 allows the integration of automation and electrification as well as energy distribution and management, thus providing
operators and other users with essential information on the overall system. If, for example, the targeted productivity of a plant does not tolerate process interruptions, the integrated communication allows to implement optimized failure scenarios for load shedding. The operator can
quickly respond and optimally use the energy available. Particularly for industries with high energy demand, the production capacities can be geared towards optimized consumption – costly peak loads can thus be avoided. ..."

ABB news letter [PDF: English - German]

Power plant projects that use IEC 61850 for system integration ... [PDF: English]

Use of IEC 61850 in Power Plants (hydro, wind, ...) [PDF: English]

Tuesday, April 28, 2009

Why do we need Single Point and Double Point Status?

The Single Point signals and Double Point signals for Status monitoring of e.g. circuit breaker switch positions in substations are quite special in process control systems. The basic definitions have been made in fifties of the last century - when remote monitoring was realized with electro-mechanical relays, contacts, wires and relay inputs.

The most simplest approach was to use a single contact to signal a switch position: 110 V on the input contact = Switch closed; no voltage = Switch open. This single contact is called "a Single Point Signal":

SinglePointStatus

This solution was not very safe. Think of broken wire that was not detected. Or of a contact that was not closed for a long time. After that time the contact may have been corroded so that after closing the contact mechanically there is no electrical contact! The receiving device would not be informed that the switch has been closed!

Engineers found solutions to solve the problem: They invented the "Double Point Signal":

DoublePointStatus

Single Point and Double Point Data Types are still in use in serial communication systems like DNP3, IEC 60870-5-104 or IEC 61850. The IEC 61850-7-3 defines these types -- so-called Common Data Classes (CDC).

The reason for Double Point Status in serial communication systems (like the IEC 61850-7-3 CDC DPS) is quite different: the two bits for the representation of "open" and "close" make the status message secure. A single bit error does not cause a wrong interpretation of the value! The value will not be valid anymore.

More details on the basic modeling approach of process information and information exchange is provided in the comprehensive and neutral seminars and training classes of NettedAutomation GmbH (details). Now is the time to get more education.

Q&A on IEC 61850 from attendees of seminar in Moscow

The attendees of the IEC 61850 seminar held in Moscow (Russia) recently provided more than 10 questions on IEC 61850 that have been answered in written form [pdf, 47 KB] ... the questions have been discussed during the class. Usually attendees provide questions prior to the classes.

Monday, April 27, 2009

Protocol Message Repository

If you are looking for traces of packets (e.g, MMS messages) you can find a huge and growing repository provided by Mu Dynamics: Pcapr.

Have a look - it has many features. MMS message traces ...

Saturday, April 25, 2009

Green Power Superhighway

US FERC (Federal Energy Regulatory Commission) supports a proposed 3,000-mile regional “green power superhighway” designed to deliver wind-powered renewable energy from the upper Midwest to consumers in and around Chicago, Minneapolis and other load centers.

The cost for the new 765 kV transmission system is estimated at $10 - 12 billion and deliver up to 12,000 megawatts. News letter [pdf]

Under the assumption of 3 MW wind turbines it would require some 4,000 wind turbines to be installed!

What do these systems need? Information and communication systems ... a bright future for today's communication standards.

Friday, April 24, 2009

Mit oder ohne Gateway - geschlossen oder offen?

Seit Mitte der achtziger Jahre des letzten Jahrhunderts wird immer wieder über offene und geschlossene Informations- und Kommunikationssysteme diskutiert. Während einer der ersten öffentlichen Konferenzen zu offenen Systemen (etwa 1983) habe ich gehört, wie Kritiker offener Systeme die Lokalen Netzwerke (LAN) und offene Systeme wie folgt kommentierten:

LAN = Leidvolle Anwender-Neuorientierung

Offene Systeme - "Wer offene Systeme will, der ist nicht ganz dicht!"

Wie sieht nach 25 Jahren im industriellen Automatisierungsbereich die Situation aus?

Offene Systeme werden sich global - mal mehr und mal weniger - in vielen Anwendungsbereichen durchsetzen! Ohne Zweifel!

Damit offene Systeme "dicht" bleiben, müssen angemessene Sicherheitsmaßnahmen ergriffen werden! Viele Systeme sind nicht "ganz dicht" - sie laden regelrecht zu einem "Besuch" ein! Wenn der Zugriff auf viele Informationen möglich ist, dann ist es sehr wahrscheinlich, dass bald jemand davon Gebrauch macht! Aus Neugierde oder zum Schaden des Systembetreibers!

Ethernet-Lösungen, mit denen "Das Ende der Gateways" (die totale Offenheit) verkündet wird (Artikel in der C&A 03/2009), können sinnvoll eingesetzt werden, wenn angemessene Security-Maßnahmen ergriffen werden, die das Gesamtsystem (traditionelle IT und Prozess-IT) "dicht", das heißt, sicher machen".

Auszug aus dem C&A-Artikel: "Ein Ethernet-Netzwerk für alle Applikationen eines Unternehmens – ohne Bruch zwischen Echtzeit- und Standard-Anwendung! Diese Vision beschäftigt seit Anfang des Jahrtausends intensiv die Automatisierungstechniker. Harting zeigt zur Hannover Messe erstmals Switches, die nun beide Welten zusammenführen – ohne die bis dato notwendigen Gateways."

Offenheit ist bei machen schon zur Religion geworden: "Echelon is agnostic about modems, Lund explained as he stood for a 30-minute interview. “Our only religion is it must be IP.”" (Quelle: SmartGridToday)

Die notwendigen IT-Security-Maßnahmen werden in vielen Prozess-Automatisierungssystemen sehr oft (zu oft!) als Aufgabe der IT-Abteilung gesehen! Mit der zunehmenden Ethernet- und IP-Vernetzung muss in Automatisierungssystemen eine vernünftige Balance zwischen einer notwendigen funktionalen Offenheit und einer hinreichenden System-Sicherheit gefunden werden.

Haben Sie Fragen zur IT-Sicherheit von Systemen, in den offene Kommunikationsnormen wie IEC 61850, IEC 61400-25, IEC 60870-5-10x angewendet werden? Kontakt.

Low voltage electrical measurements and general I/O's with IEC 61850

Camille Bauer (Switzerland) offers a measurement IED for electric distribution systems or industrial facilities compliant with IEC 61850. The IED can also be used as a Gateway for many other input and output signals. SINEAX CAM-POWER is designed for measurements in electric distribution systems or in industrial facilities.

The following Logical Nodes are supported:

image

The IED is a good example that demonstrates that advanced IEDs can run several applications: measurements, general I/O's or logic functions. The classical PLC (programmable logic controller) with its special hardware has been converted to a software that can run on almost any hardware platform with Ethernet, TCP/IP and upper layer protocols.

Protection IEDs have integrated Ethernet switches ... it is likely that classical Ethernet Switches will soon provide general I/O's and logic function. IEDs will become more multifunctional!

Upper layer protocols and other definitions like information models and configuration language according to IEC 61850 will play a crucial role in future automation systems.

Friday, April 17, 2009

NERC refers to IEC 61400-25

The North American Electric Reliability Corporation (NERC) has published a special report “Accommodating High Levels of Variable Generation” on April 16, 2009 . The report discusses the planning and operation of the future power system with high volume of flexible grid resources like wind power or plug-in hybrid electric vehicles. A crucial element in the future power delivery system will be the information and communication technology.

IEC TC 57 and TC 88 have published International Standards for most crucial aspects of future power delivery systems: IEC 61850 and IEC 61400-25 (extending IEC 61850 for wind power). The NERC report refers to IEC 61400-25 in clause 2.4.3:

"2.4.3. Power Management
For variable generation to provide power plant control capabilities, it must be visible to the system operator and able to respond to dispatch instructions during normal and emergency conditions. Real-time wind turbine power output, availability, and curtailment information is critical to the accuracy of the variable generation plant output forecast, as well as to the reliable
operation of the system. It is critical that the Balancing Area operator have real-time knowledge of the state of the variable generation plant and be able to communicate timely instructions to the plants. In turn, variable generation plant operators need to respond to directives provided by the Balancing Area in a timely manner. The need for this information was clearly illustrated during the restoration of the UCTE system following the disturbance of Nov. 9, 2006 when there was a lack of communications between distribution system operators (DSOs) and transmission system operators (TSOs) delayed the TSO’s ability to restore the bulk power system.

Therefore, as small variable generation facilities grow into significant plants contributing significantly to capacity and energy, balancing areas will require sufficient communications for monitoring and sending dispatch instructions to these facilities. (Foot note: An international standard communications protocol has been prepared, IEC 61400-25, Wind turbines – Communications for monitoring and control of wind power plants – Overall description of principles and models, International Electrotechnical Commission, December, 2006).

Further, Balancing areas and generator owner/operators must ensure procedures, protocols, and communication facilities are in place so dispatch and control instructions can be communicated to the variable generation plant operators in a timely manner. Adequate communication of data from variable generation and enhanced system monitoring is not only a vital reliability requirement, but is also necessary to support the data analysis posed by other recommended NERC and Industry actions."

[Press Release]
[Executive Summary]
[Full Report]

Thursday, April 16, 2009

Process and Power Automation use ONE Integration Standard - IEC 61850

Comprehensive automation systems are in use in many application domains like:

  • Factories (factory automation),
  • Chemical and power plants (process automation),
  • Electrical transmission and distribution substations (substation automation)
  • ...

Usually these domains have their own solutions - there are many reasons (often historical reasons). They even have their own standardization bodies: Factory automation: ISO TC 184, process automation: IEC TC 65, and substation automation: IEC TC 57.

From a system integration point of view this is non-productive. Very often the electrical system was understood as somehow special - may be because of the danger of dealing with high voltage!!

The above mentioned automation domains need solutions to exchange the huge amount of information for control and monitoring. In the past very often these domains used their own communication solutions. There was no consensus between the different domains to define a seamless solution that makes integration easier - to safe time and money, ...

The first approach to overcome the many proprietary solutions was the project MAP (manufacturing automation protocol) some 25 years ago. It failed - because it was simply to early. Just a few people understood the need of seamless integration. ISO TC 184 has published the system integration standard ISO 9506 (MMS) in 1990 - but it is used since the mid nineties all over in the electric power world: in IEC 60870-6-TASE.2, IEC 61850, and IEC 61400-25.

After the "fieldbus war" we still have the domain specific approaches, solutions and products. The fieldbus discussion has focused too long on the best approach of the field instrumentation - now we have tens of normative fieldbus standards! A seamless solution for system integration was developed by IEC TC 57: IEC 61850 "Communication networks and systems for power utility automation". The restricted scope on power utility automation has been chosen because IEC TC 57 has the scope electric power systems. Most experts outside the "dangerous" electrical world have not (yet) thought to use an "electrical" standard for non-electrical applications.

In fact the solution IEC 61850 can be used in almost all application domains of automation. At least for the three domains: factory automation, process automation, and substation automation. AND: All these application domains use a lot of electric power!! Electric power is one of the most crucial raw material for any application. Any plant manager has to pay more attention to the electric power system!

ABB has realized the crucial integration needs cross several application domains: “We still have separate work spaces for power people and process people, but everyone does more of their work the same way, using the same paradigm. This means more and better optimization, lower total costs and more minimization of risk.” according to Stefan Bollmeyer, ABB fieldbus product manager for its System 800xA. He says also: "Many users have their own department and kingdoms, and they want them to stay just as they are.”

"To help process control and power staffs cooperate on achieving better electrical integration, ABB recommends they adopt a unified integration method based on a single system environment, use a fieldbus network to handle electrification control and management, and use the IEC 61850 standard to tie together process instrumentation, process electrification and power distribution networks." according to a report about ABB's March 23-25, 2009 event in Orlando, Florida (USA). Read Report.

With the Ethernet, TCP/IP and XML based information exchange in most of the application domains it could be expected that IEC 61850 will be used as the standard for seamless information, information exchange and system configuration. The information model of IEC 61850 "MMXU" (electrical measurements) providing objects of three phase AC voltages (PhaseA, PhaseB, PhaseC or PhaseAB, PhaseBC, PhaseCA) or three AC currents (PhaseA, PhaseB, PhaseC) can be used where three phases are installed: in any application domain.

The same AC electrical system can be found in power plants, power transmission and distribution, and any other plant. Some companies have realized that IEC 61850 could be used as the single seamless solution in most application domains. Nobody would come up with a special 5 phase AC system for his application domain! IEC 61850 could play the same standard role as does the three phase seamless AC electrical system - even we have 50 Hz or 60 Hz systems!

IEC 61850 will be accepted some time down the road as the seamless international integration standard like the three phase AC electrical system is the international standard for electric power.

IEC 61850-9-2 Edition 2 out for CDV ballot

The Committee Draft for Vote for IEC 61850-9-2 Ed.2 has been published the other day (document 57/996/CDV):
Communication networks and systems for power utility automation - Part 9-2 Specific Communication Service Mapping (SCSM) – Sampled values over ISO/IEC 8802-3

Closing date for commenting and voting: 2009-09-11
(contact your national TC 57 committee for a copy).

The following are two extensions in the CDV of Edition 2:

  • Link Redundancy: Parallel Redundancy Protocol and High Availability Seamless Ring (according to IEC 62439-3) - optional
  • Sample Mode has been added to the control block and sample value message:
    0 = samples per nominal period (DEFAULT)
    1 = samples per second
    2 = seconds per sample
    If not available (backward compatibility) the
    default value is 0.

Wednesday, April 15, 2009

Full day seminar and two day Conference on IEC 61850 in Kuala Lumpur, May 26-28, 2009

International experts will present and discuss the latest development in the domain of IEC 61850 for power systems ... especially for substation protection and automation.

A full day pre-conference workshop on IEC 61850, IEC 60870-5, DNP3, CIM, Security, Decentralized Energy, Smart Grids, ... will take place on May 26.

The event will take place in Kuala Lumpur (Malaysia) on May 26-28, 2009.

Program and registration information [pdf, 530 KB]