The IEC 61850 Tissue Database reached 1900 Tissues

The IEC 61850 Tissue Database is a very useful tool to help improving the quality of the standard series. The first Tissue (#1) was posted almost 19 years ago. On December 12, 2023 the Tissue #1900 was posted. In average two Tissues per week have been posted. The Tissue process is accepted all over.

The other day I received a question on the definition of power factor (MMXU.PF). The definition is contained in the Logical Node class MMXU of part IEC 61850-7-4:

When I read the definition I was wondering that there was no definition of the sign of the PF. I thought that somebody must have found this long before me ... I checked the Tissue Database to find the corresponding Tissue ... which is #1721 (Power factor related data objects in LN MMXU) dated September 22, 2020.

The following figure depicts the corrected definition.

Recommendation: In case you belief you found an error in the standard series, check first the tissue database and search ... you may find the correct answer ...

How Many and Which Information Models are defined in IEC 61850?

I guess you have heard that IEC 61850 defines a lot of Information Models. Yes, You are right.

The models are managed exclusively by the corresponding working groups with the Enterprise Architect UML Tool (the UML data base is for internal use only). The model version:

UML model of 61850 (wg10built6-wg18built3-wg17built5-jwg25built2-tc17built1-tc38built1.eap)

comprises the following number of Logical Node Classes, Data Objects (Attributes), Enumerations and Abbreviations:



An excerpt from the UML modes looks like this:



The UML Model is the single source data base that is used for the extensions and maintenance of the model, as well as the generation of Word or PDF documents ... The PDF documents are sold by IEC and other organizations.

You may complain that the standards are not for free ... hmm ... BUT look: You can download the various Code Components for free.

Click HERE for the Code Component for IEC_61850-7-4.NSD.2007A2.light.zip (IEC 61850-7-4 2007A2 NSD light, see the IEC 61850-7-4:2010 for full legal notices). The full version has additionally the semantic descriptions of the models.

Example of Enumeration:


Example of excerpt of LN Class MMU:



Click HERE to see the list of all Code Components as per today ... more to come soon.

To my understanding you can model many required information generated and consumed by a huge number of applications in almost all application domains of automation in the electrical system and beyond.

As the above example of MMXU shows, you can use this LN Class wherever you have 3 phase AC system!! In a building heating system for the electrical values of a compressor or a fan or a pump or ... the blue sky is the limit for the applications.

Click HERE to learn about crucial details discussing the LN Class MMXU and how it can be applied ... you may have never expected this comprehensiveness of the MMXU.

Note that the 3 phase system was first (more than 100 years ago) - then we have put a facade in front of the measurement function which exposes the measurements as data objects of the class MMXU. The application has driven the class - not vice versa.

The current edition 2.1 models defined in IEC 61850-7-3 and 7-3 are listed in the contents tables of the preview documents. The following Preview documents (free access) for models of the edition 2.1 consolidated versions are available:

Preview IEC 61850-7-3 Edition 2.1
Preview IEC 61850-7-4 Edition 2.1

Example of 7-4 from the preview:



In case you find any error in the standards, please visit the Tissue Database:
https://iec61850.tissue-db.com/parts.mspx

Dangerous Situation in the European Electric Power System Caused by "frozen" Measurements

Measurements of power flow (Watts in export or import) are very crucial for Load Frequency Controller … wrong (i.e., “frozen”!) measurements have caused almost a big blackout in Europe in January 2019.
What happened: the measurement of power of the lines between two transmission systems (Germany – Austria) were frozen when the export value of 723 MW from Germany to Austria was measured (which was a result of 34 GW wind power generation in Germany). Later the wind power generation decreased to 4 GW … and the measurement (as input to the controller) many hours later still used the input value of 723 MW !!! In such a meshed power network it is unlikely that such a value is constant …

Oops … something went absolutely wrong!

Report by exception (on a value change as used for the above measurement) is great … as long as there are changes figured out and reported. A frozen value does not cause a change and thus no new value will be reported … No receiver should expect that the export power is constant (723 MW) for days!! The sensors may have worked fine … but the software and communication failed … on both sides (sender and receiver). A receiver should not trust that the software and communication is working fine all time.
Here are some measures to monitor the communication (by the receiver) to figure out if the communication is OK:

1. Ping (in case of TCP/IP) (if no response after some time: raise flag)
2. TCP Keep-alive (if no keep-alive message in t bigger keep-alive: raise flag)
3. Polling by receiver (if no response after some time: raise flag)
4. Periodic reporting (if no report in t greater period: raise flag)
5. In case of no message received in a configured time period (in case of using IEC 61850 Reporting) the receiver should check if the report control block is enabled and is using the correct configuration values like trigger option, …
6. Check if the sequence of received values are plausible
7. Use redundant systems (comm, …)
8. …

Check out the official Entso-E report (with links to more details):

https://www.entsoe.eu/news/2019/05/28/entso-e-technical-report-on-the-january-2019-significant-frequency-deviations-in-continental-europe/

This reminds me on the Boeing 737 MAX disaster … maybe a programmer left the vendor of the load frequency controller and hired with Boeing … I am kidding.

How many programmer or people that configure power control systems and communication systems that lack experience with complex systems like a plane or a power system. Where are the “grey-hair” experts that would tell you in minutes how to … ? They may enjoy the beach with warm water and sun shine – relax and spend the pension for ...

It is not sufficient to have no ideas – one should also be unable to implement them.

I expect that more of these problems will hit the street once we have far more control, monitoring and communication in the smart(er) grids of medium and low voltage. Note that the problem in January 2019 occurred at transmission level!! … where more resources (higher budgets) are available (in the past).

Have a great weekend – with power.

Pt 100 Temperature Relay with IEC 61850 GOOSE

Ziehl (Schwäbisch Hall, Germany) has integrated IEC 61850 GOOSE into their Pt 100 temperature relay for up to 12 sensors with electric 10 MBit/s Ethernet interface.

The TR1200IP can be used wherever multiple Pt 100 sensors (up to 12) need to be evaluated simultaneously:
- Motors or generators,
- also with simultaneous monitoring of bearings or, e.g., exhaust temperatures
- Transformers, also with additional core-temperature monitoring
- Machines and plants
Type TR1200IP temperature relays register the temperature of up to 12 sensors simultaneously and provide the values to the electric 10 MBit/s Ethernet interface.
2 IP protocols are supported, so the registered temperatures can be subsequently evaluated by connected devices that are linked with the TR1200IP via an Ethernet network. In motors, that could be a motor contactor, in transformers a transformer contactor with integrated overload function and thermal monitoring.
An alarm relay reports devices and sensor errors. Sensor breaks or sensor short-circuits are also transmitted via the protocol to the connected evaluation unit.

Click HERE for a general overview.
Click HERE for GOOSE configuration.
Click HERE for the manual.

The GOOSE messages could be received by an HMS SG Gateway either as a client or a server. The SG Gateway could convert the received GOOSE messages into an IEC 61850 server to provide Reporting and Logging and convert to IEC 60870-5-104 or DNP3.

Optical Fibre for Temperature Measurement in Power Systems

Optical fibres are known to be used in power systems because they withstand the rough conditions in high voltage environments – as such they are used in Substations for carrying messages, e.g., according to IEC 61850.

There is another very interesting use case of optical fibres in power systems: in generation, transport, distribution, and loads. One of the crucial measurements that can be applied to more efficiently use of electric power is measuring temperatures. But you may state that installing a lot of temperature sensors could be quite expensive!

With the application of optical fibre for measuring temperatures it seems to be a very promising approach to reduce the amount of power needed for many critical process like in huge data centers, high voltage lines and cables, transformers, switch gears, to name a few.

According to alquist (a UK based company specializing on measurement systems using fibres) there are many advantages of fibre as a temperature sensor:

• Simultaneously measures temperature and position over long distances
• Low cost – the sensor is made from standard 50/125 optical fibre zip cord - very cost effective
• Immune to shock/vibration and electromagnetic interference
• No electronics, wireless, batteries or moving parts in monitoring zone. Totally passive, minimal maintenance.
• Inherent high reliability (fibre has a design life of 30+ years)
• High temperature range -200°c to +500°c
• Extremely small for access in legacy areas with restricted space
• Easily installed in without any downtime or interruption of service

There are an incredible number of applications for fibre optics beyond their use as a simple communications links.

Download a very useful presentation given by Andrew Jones (alquist) [pdf, 2.8 MB]

The availability of myriads of “measurement signals” from various processes allows to more efficiently use energy, i.e., to reduce the amount of energy we need to consume to service our needs for modern life.

What ever will be measured in energy supply systems could be modeled and communicated with IEC 61850 – The Communication Standard for power system automation. One crucial focus of IEC 61850 is on measurements!

Transformer Protection and Monitoring IED with IEC61850@Chip

C&S Electric Ltd (India) has developed a Transformer Protection and Monitoring IED with an IEC 61850 interface build on the Beck IPC Chip “IEC61850@CHIP” with SystemCorp’s IEC 61850 solution integrated.

Click HERE for more technical information.

IEC 61850 provides a lot for the Smart Electrification

The recently published IEC white paper :

Coping with the Energy Challenge
The IEC’s role from 2010 to 2030
Smart electrification – The key to energy efficiency

discusses the need of standards! No surprise, or?

Click HERE to download the white paper [pdf, 1,9 MB]

The paper concludes on page 51:

"The standards should cover connection (especially of fluctuating sources), stability, “intelligence” (required functions of the IT applications controlling the grid), and minimum systemic efficiency as well as how to measure it. Aspects to deal with include balancing demand and generation, power quality, harmonic current emissions, voltage flicker, voltage fluctuation and islanding prevention. The standards should allow for the necessary differences in approach and choices made in different countries; thus some of the resulting publications may be non-normative.
In order to facilitate implementation, the MSB [IEC Market Strategy Board] further recommends the IEC and cooperating organizations to organize a public symposium on what the necessary standards and other IEC publications on the “smart grid” should contain."

The paper states at very beginning:

"As the first IEC President, Lord Kelvin, always said: “If you cannot measure it, you cannot improve it!”. This statement is especially true here: without measurement you can’t credibly demonstrate energy efficiency improvements. The IEC provides and will continue to provide many of the measuring standards that are the basis for benchmarking, energy audits and compliance assessments."

The edition 2 of IEC 61850-7-4 (Information models) covers already many models of these measurements:

5.10 Logical nodes for metering and measurement LN Group: M
5.10.2 LN: Environmental information Name: MENV
5.10.3 LN: Flicker measurement name Name: MFLK
5.10.4 LN: Harmonics or interharmonics Name: MHAI
5.10.5 LN: Non-phase-related harmonics or interharmonics Name: MHAN
5.10.6 LN: Hydrological information Name: MHYD
5.10.7 LN: DC measurement Name: MMDC
5.10.8 LN: Meteorological information Name: MMET
5.10.9 LN: Metering Name: MMTN
5.10.10 LN: Metering Name: MMTR
5.10.11 LN: Non-phase-related measurement Name: MMXN
5.10.12 LN: Measurement Name: MMXU
5.10.13 LN: Sequence and imbalance Name: MSQI
5.10.14 LN: Metering statistics Name: MSTA

5.12 Logical nodes for power quality events LN Group: Q
5.12.2 LN: Frequency variation Name: QFVR
5.12.3 LN: Current transient Name: QITR
5.12.4 LN: Current unbalance variation Name: QIUB
5.12.5 LN: Voltage transient Name: QVTR
5.12.6 LN: Voltage unbalance variation Name: QVUB
5.12.7 LN: Voltage variation Name: QVVR

Click HERE for the preview of IEC 61850-7-4 (first 20 pages) to see the complete list of Logical Nodes defined.

If there is any (measurement) information found in real electrical system not yet modeled and standardized, you can define extension according to well defined extension rules in IEC 61850-7-1 (name space concept).

There is no need to define another series of (information models and information exchange) standards for electrical grids.