Friday, May 3, 2024

My Friend Andrea Bonetti Has Been Appointed As New Chair of IEC TC 95 (Protection ...)

Please note that my friend Andrea Bonetti (currently working for Megger, Sweden) has been appointed as the new chair of IEC TC 95 (Measuring relays and protection equipment).
Andrea and I have conducted many training courses on IEC 61850 ... and cooperated in consulting services related to protection, communication, IEC 61850, ...
I wish Andrea the best for his future ... managing the process of how power systems are protected. It is a huge task!!

Some Hints On Static And Dynamic Reporting According To IEC 61850

Let me briefly help to understand the term dynamic and static regarding reporting:

Every report control block must be “created” in an SCL file – no way to create a report control block with a service.

Several report control block attributes can be configured in an SCL file or set (overwritten) by a (MMS) service.

A data set can be “created” in an SCL file or by the optional service CreateDataSet.

The term “dynamic” could apply to the setting/overwriting of report control block attributes, and the creation of data sets.

In one case with a Gateway from a well known vendor (as a client) I have seen that the client always defines the data sets dynamically!! And links a given report control block to that created data set. If a server does not support the service CreateDataSet, then you get into trouble …

A nice summary can be found here:

For operational functions (protection, control, …) the only dynamical services that should be allowed are to enable or disable the report control blocks. This should be configured in the corresponding SCL file for an IED by setting the attributes to “Conf”:

<ReportSettings cbName="Conf" datSet="Conf" rptID="Conf" optFields="Conf" bufTime="Conf" trgOps="Conf" intgPd="Conf" resvTms="true" owner="true" />

Example of a device from a well known vendor I received the other day:

<ReportSettings cbName="Conf" datSet="Dyn" rptID="Dyn" optFields="Dyn" bufTime="Dyn" trgOps="Dyn" intgPd="Dyn" resvTms="true" owner="true" />

Dynamic setting or overwriting of control block attributes or creation of a data set by a service could cause a lot of troubles!! Client and server should not allow it!  A well known RTU (client) overwrites dynamically a report control block attribute (in the server) immediately after it has connected to the server … that should not be accepted.

It could have a big impact on testing, e.g., you expect that a report (or GOOSE, SMV) message has a structure defined by a data set “X with 5 members” (according to the SCL file) … but you receive a message with 3 members (from data set Y) only … because somebody has overwritten the attribute “DatSet” of the report (GOOSE, SMV) control block. 

IEC 61850 is very flexible … to cause trouble … if you want to trust, that the device is 100% as shown in the SCL file, then NO dynamic modifications should be allowed!

Do you want have a problem - no problem!

By the way, Andrea Bonetti wrote the other day: "It is a good practice followed by the majority of the TSOs that do write their own IEC 61850 specification (sort of “dynamic reports are not allowed unless for testing/debugging”). It is also mentioned in IEC TS 63266:2023 (Representation of communication in power utility automation)."