Why Is It So Easy To Map IEC 61850 Signals to JSON Objects?

IEC 61850 defines Device Models for the exchange of information between any two or more entities. The Models are structured as unique branches of a tree.That means:

Each path from the Device (Root) to 

any node or leave of the trees is unique

The signals are composed of an access reference (LDName/LNName.DOI. ...) and the value that corresponds with the path.

Example of two leaves:
LDName/Tran1STMP1.Tmp.mag.f = 23.5 (Temperature value)
LDName/Tran1STMP1.Tmp.units.SIUnit = °C (Temperature engineering units)

These are key-value pairs that could easily map to JSON Objects:

"LDName/Tran1STMP1.Tmp.mag.f " : "23.5"
"LDName/Tran1STMP1.Tmp.units.SIUnit" : °C

These JSON objects are

• Light-weight
• Language independent
• Easy to process with Python, ...
• Text based and human readable 
• JSON Schemas could support automatic (syntax and semantic) checks
• JSON is supported by many controllers

The controller of our PV inverter from Fronius has an http/JSON interface. The following request (lines 1-3) returns many common inverter data (line 21ff):



Lesson learned: Controller in inverter could easily provide an http/JSON interface.

The Device Model is a virtual model that could be configured using the SCL (System Configuration Language, IEC 61850-6). The Device Model is implemented in an IED and could be accessed to get the self-description, read, write, send/receive reports, publish/subscribe, ...

An IEC 61850 Server hosted by an IED could easily map the model to JSON objects that may be communicated with MQTT, HTTP, ...

The mapping to JSON is quite easy. It could be implemented by a simple automatic process that parses the model (SCL/XML), searches for the paths and concatenates the names from the root to the leaves to get the reference! AND: the mapping preserves the semantic - the meaning represented by the path name.

The mappings of IEC 61850 Models to IEC 60870-5-104, DNP3 or Modbus would result in messages that have lost the semantic of the signals. These solutions have mainly numbers as reference - these numbers have no meaning in the communication.

FDIS Ballot for Amendment 1 for IEC 61850-7-2, 7-3 and 7-4 Edition 2 Approved

The ballot of the three amendments (Amendment 1 for IEC 61850-7-2, 7-3 and 7-4 Edition 2) passed the FDIS process. All three amendments have been approved by 100 %.

The next step will be the IS publication of the three amendments.

It is likely that there will be a consolidated version of each of the three parts - means: the amendment is merged into the edition 2 versions and become edition 2.1.

IEC 61850 Sampled Values and GOOSE Messages Reduce Complexity and Cost

Synaptec Ltd (a spin-out technology company from the University of Strathclyde, UK) developed a distributed electrical sensing technology platform using IEC 61850. The approach allows measured values from up to 50 current transformers to be acquired passively using a single optical fibre core over a distance of up to 50 km. These measured values can then be utilised as part of centralised PAC schemes, or communicated to traditional PAC devices for analysis via IEC 61850-9-2 / 61869-9. By centralising current measurements, this method eliminates the need of having multiple protection relays at each line ends, complex time synchronisation systems at measurement points, and complex telecommunications equipment among the distributed PAC devices.

Click HERE for downloading the 12 page paper (Differential protection of multi-ended transmission circuits using passive distributed current sensors) describing the application and approach to solve a very crucial challenge.

Another paper (Implementation of centralised, numerical busbar protection using distributed photonic current sensors) describes the design and testing of the first centralised busbar protection scheme that makes use of distributed photonic current sensors and IEC 61850. By utilising distributed, passive sensors which are interrogated purely using standard optical fibre, the requirement for active units in the substation yard is completely eliminated. Additionally, the use of copper wiring from CTs to measurement units may be eliminated. The scheme, designed and built for Statnett by Synaptec, will be installed and trialled at Statnett’s Furuset R&D substation near Oslo, Norway. A prototype centralised busbar protection algorithm, validated with the University of Strathclyde, will run on the central merger unit to prove the principle of centralised busbar protection using a single active IED.

Click HERE for downloading the paper.

Click HERE for the Synaptec news (Norwegian TSO Statnett innovates with Synaptec technologies):

With one system able to instrument 50 locations synchronously, 6 busbar feeders will be independently and simultaneously protected by one system, with capacity to spare for novel temperature and vibration monitoring of nearby HV assets, such as transformers.

The development and the applications show that the standard series IEC 61850 has all the "tools" helping to keep the power flowing and the grass green - at all voltage levels.

Tissue Process for IEC 61850-8-2 open for posting Tissues

Please note that the Tissue Database is now open for part IEC 61850-8-2:

Communication networks and systems for power utility automation –
Part 8-2: Specific communication service mapping (SCSM) – Mapping to Extensible Messaging Presence Protocol (XMPP)

http://tissue.iec61850.com/part/52

VDMA-Leitfaden: "Interoperabilität durch standardisierte Merkmale“

Der VDMA (Verband Deutscher Maschinen- und Anlagenbau) hat diese Woche einen sehr interessanten 70-seitigen Leitfaden zu Industrie 4.0 veröffentlicht!

Interoperabilität durch
standardisierte Merkmale
Leitfaden für Industrie 4.0

HIER klicken für mehr Information und den Kontakt.

„Der Leitfaden „Interoperabilität durch standardisierte Merkmale“ beschreibt, wie Signale und
Werte zwischen Fertigungseinheiten ausgetauscht werden und folgt so der Industrie 4.0-Idee.
Das Schlüsselwort ist "Standardisierung". Produkte, Einzelteile Baugruppen oder
Anlagenelemente sind durch Merkmale beschrieben, die in einem Format übertragen werden.
Die Merkmalbeschreibung sowie das Übertragungsformat liegen in standardisierter Form vor
und bilden eine gemeinsame "Sprache". Diese Sprache bildet die Basis dafür, dass empfangende
Systeme die Daten korrekt verstehen, ...“

Der Leitfaden hat natürlich meine Neugierde und mein Interesse geweckt!

Die hier empfohlenen Maßnahmen und Vorgehensweisen gehen genau in die richtige Richtung ... sie setzen im Prinzip da auf, wo wir Anfang der 90er Jahre mit MAP 3.0 und den MMS-Companion-Standards aufgehört haben!

Seit 2005 haben wir zwei Normenreihen (IEC 61850 und IEC 61400-25), mit denen ein guter Teil der im Leitfaden vorgeschlagenen Methoden realisiert wurde und global angewendet wird – leider „nur“ im Bereich der elektrischen Energieversorgung (und hier anfangs zunächst im Hochspannungsbereich). Vor allen elektrischen Systemen mit mehr als 400 V haben die meisten Automatisierer ohnehin großen Respekt – und lassen die Finger von Automatisierungslösungen in diesem Bereich. Das hat sich heute schon vielfach als Fehler herausgestellt.

Die meisten Experten - auch aus dem Maschinen- und Anlagenbau - erwarten nicht, dass wir für die anfangs auf die elektrische Energieversorgung fokussierte Automatisierungswelt Lösungen definiert haben, die auch in vielen anderen Bereichen angewendet werden können!! Ja wirklich!

Es ist ja schon (fast) alles definiert und genormt worden – nur noch nicht von allen!!

IEC TC 57 Just Published the IEC 61850-90-11 on Logics

IEC TC 57 Just Published the 90 pages of the Draft Technical Report IEC 61850-90-11 (57/2129/DTR)

Communication networks and systems for power utility automation –
Part 90-11: Methodologies for modelling of logics for IEC 61850 based applications

Voting closes 2019-10-04

"This Technical Report of IEC 61850 describes the methodologies for the modelling of logics for IEC 61850 based applications. ... the technical report

• Defines different application uses cases where all aspects to be considered are clearly identified.
• Describes the functional requirements and the intended engineering process
• Proposes a suitable solution in the context of IEC 61850 based on an investigation of the different possibilities to model the logic.
• Describes the impact on various parts of IEC 61850"

If, when and how this Technical Report will impact implementations of tools and IEDs is quite open. I remember that we had heated debates on the question how to deal with (internal) logics already some 10 years ago.

If you are planning to apply IEC 61850 - please DO NOT wait until this part 90-11 offers stable definitions ... IEC 61850 (as it is defined today) has enough to get started! ;-)

Crucial Vulnerabilities Exist in the VxWorks IPnet Stack

According to Security Week (reported the other day):

"In late July, IoT security firm Armis disclosed eleven vulnerabilities found by its researchers in the VxWorks real time operating system (RTOS). The flaws, six of which have been described as critical, can allow a remote attacker to take control of impacted systems.
Armis said the vulnerabilities exist in the VxWorks IPnet stack and they expose over 200 million mission-critical devices from around the world to attacks, including in the healthcare, manufacturing, cybersecurity, tech, and industrial automation sectors. ..."

Devices from several vendors might be impacted ...

Click HERE for the full report. There you find links to the vendor's recommendations ... You know what that could mean? One vendor notes: "Applying the update causes the device / module to go through a single restart cycle."

Beck IPC offers MQTT@CHIP in addition to IEC 61850 and other protocols

Beck IPC (Wetzlar, Germany, a subsidary of HMS) is known for their solutions on a single CHIP offering support for IEC 60870-5-104, IEC 61850, Modbus, CANBus, Profibus, Profinet, OPC UA, ... now offers MQTT@CHIP as an additional solution.



The MQTT can be configured on the WEB PLC like it is implemented for other protocols:



In the above example I have mapped a signal from an IEC 61850 Server the signal MMXU1.TotW.instMag.f to a MQTT message. This way you can tag the signal as a JSON Object!!

JSON Objekte:
{ „MMXU01.TotW.instMag.f“:  2325, „MMXU01.Hz.instMag.f“:  49.98 }

Message specification:



This way you can send MQTT messages with values from any other protocol or from the IEC 61850 client or server model. This way you can even map to/from GOOSE messages.

I have used the solution running on the IXXAT Smart Grid Gateway. The WEB PLC version 19.2 is required to run MQTT on the gateway.

Very well done!

IEC Draft TR 61850-90-9 - "IEC 61850 for Electrical Energy Storage Systems" Published

IEC TC 57 just published the 138 page IEC Draft TR 61850-90-9

IEC 61850 for Electrical Energy Storage Systems

57/2128/DTR
Voting closes 2019-09-27

This is one of the next crucial extensions for DER-Models of IEC 61850-7-420. This TR will be merged into the 7-420 later on.

The Introduction states: " ...This technical report is primarily based on the recommendation 5.7.4. “interface, control and standard data elements”, of the IEC white paper ”Electrical Energy Storage” published in December 2011 by the MSB. The recommendation proposes the necessity of a standardization of interfaces between storage and other grid elements, protocols for data exchange and control rules, and data elements for input, output and control information supplied by or to storage systems. ..."

Click HERE for the mentioned IEC White Paper.

"This technical report describes IEC 61850 information model for electrical energy storage systems (EESS). Therefore the report only focuses on storage functionality in the purpose of grid integration of such systems at the DER unit level. Higher level Interactions are already covered in IEC 61850-7-420. ... "

The draft defines more than 150 new Data Objects. Excerpt of the first 15 Data Objects:



The blue marked text refers to the Logical Node from which this Data Object is inherited.

This document refers to the standards IEC 61850-7-x and defines additional very crucial information for the configuration, control, monitoring of a battery system.
It is very crucial for the success of the DER models to get implementation and application experience with these very comprehensive and complex models.
Taking into account that the mentioned White Paper was already published in 2011, we learn a crucial lesson: It took a lot of time to get where we are today. And it will take years to get these definitions implemented and used in the power delivery systems. In the mean time you need to tap the experience of engineers that understand the possible use-cases that can harvest the benefits of applying these standards.