Standard open common data format (CDF) for power systems


#1

Hi, first post in this forum!

I’m wondering how close (or far) we are to a truly standard, common data format (CDF) for describing power systems? The IEEE CDF is outdated and it looks like the raw PSS/E format is unofficially recognized as the “standard” data exchange format between commercial softwares.

I’ve found a lot of information on CDF’s for energy models (i.e.: Do-a-thon: Draft for ‘energy’ datapackage standard (?)), some for transient data (IEEE C37.111), but not much for the power system detailed description.

Is there already an open standard being discussed? Is there already an open CDF modders should aim to integrate to their applications to facilitate data exchange between modelling softwares? If so please let it not be XML…

For example I’m currently developping a software that extracts a network’s information from an excel file, builds a SQLite3 database (my custom format, tailored for my specific needs), and converts it to PyPSA, GridCal and PSS/E to either run simulations using these tools or simply exchange in what appears to be the current CDF in use (PSS/E). A truly standard open CDF would greatly simplify development and hopefully enforce sane practices (ex.: no storing of calculated data in the CDF). It would allow me to very easily add other open modelling softwares to the mix, without having to spend hours converting from one data format to the other.

Ideally the standard should cover both the data structure (ex.: buses, branches, transformers, generators) and the file format (ex.: JSON, SQLite3). That way each modelling software could develop a simply conversion utility between the CDF and their internal structure, required for their needs (ex.: python object for each element).

Thank you.

Michel Lavoie


#2

Hi @Miek I am not very familiar with data standards for power systems, but where does the common information model (CIM) for electric power systems fit? And did you look at the ontologies page on this site for clues? Also Medjroubi et al (2017)? HTH, R.

References

Medjroubi, Wided, Ulf Philipp Müller, Malte Scharf, Carsten Matke, and David Kleinhans (2017). “Open data in power grid modelling: new approaches towards transparent grid models”. Energy Reports. 3: 14—21. ISSN 2352-4847. doi:10.1016/j.egyr.2016.12.001.


#3

Thank you Robbie, I didn’t know about the IEC CIM. It does appear to be what I was looking for, except for not being open (and using XML for data exchange). I found this API for Python but it’s unfortunately no longer maintained and the link to the doc is dead: PyCIM

I rather liked this presentation from Hawaiian Electric and Open Grid Systems. They clearly demonstrate how a common data format can reduce conversion headache.

I’ll try to have a look at the IEC CIM standard if I can get my hands on it, but I think its price is going to be prohivitive for me.

Michel


#4

Hi @Miek The Linux Foundation have been talking to ENTSO‑E about the use and development of open source software for grid operations. As that initiative proceeds, it will almost certainly be supplemented by the development of open standards for data interchange. This will be a multi‑year project though. Whether the accompanying data will also be open is another matter. I spoke to Mike Dolan, Linux Foundation some months back and data is not part of their current discussions.

To formalize this, the Linux Foundation launched LF ENERGY in July 2018 with French transmission system provider RTE. ENTSO-E hosted an introductory event in August 2018.

A promotional video on the LF ENERGY site talks about a “common grid model”. You could email Shuli Goodman, Executive Director, LF Energy Foundation for an update.

LF ENERGY follows similar flagship exercises by the Linux Foundation in the automotive and movie production areas.

To return to CIM, another other interesting thing is that it is recorded using UML. Perhaps that is a useful practice to continue. R.

References

Linux Foundation (12 July 2018). The Linux Foundation Launches LF ENERGY, new open source coalition — Press release. Linux Foundation. San Francisco, California, USA.

LF Energy — Open Source for Energy Transition. LF Energy. Website.

ENTSO-E (27 August 2018). LF ENERGY introductory event. ENTSO-E. Brussels, Belgium.


#5

Many thanks Robbie. I sent LF Energy an email and will report back.


#6

Hi all- data is definitely on our radar. So central to interoperability and also such a burden on cost. If this is of interest please join the mailing list. We are moving towards convening the governing board and the technical advisory council. Glad to hear there is interest and visibility in LF Energy!


#7

Hello @Shuli The Open Energy Modelling Initiative, who runs various venues including this forum, has no legal standing and no process for endorsing representation. But I would encourage those in our community who work on grid modeling (not me) to find someone to serve on the LF Energy technical advisory council. It would be rather useful if the necessarily detailed grid description that LF Energy develops for its purposes is also roughly compatible with the broader‑brush information that long‑haul energy modelers need. R.


#8

Hi @robbie.morrison. Thank you for your encouragement. ALL open source projects are open, regardless of membership. Anyone can work on a project. Non-members may participate fully in the technical community and with contributions, earn committer, or TSC roles on merit.

As to “It would be rather useful if the necessarily detailed grid description that LF Energy develops for its purposes is also roughly compatible with the broader‑brush information that long‑haul energy modelers need.” If there is a data model project, it would be the contributors that would ensure compatibility and would hopefully build on current efforts. This is precisely why we will need your participation. Please signup here for the mailing list: https://lists.lfenergy.org/g/main/join

Shuli


#9

Hi all,

As far as I can tell, the powsybl project from the LF Energy has its own grid model format (IIDM at https://powsybl.github.io/docs/iidm/model/), but it’s an internal model, not a model standard that’s meant to be used for data exchange between modelling softwares. For grid model exchange, they mention other closed formats (CIM, CGMES, UCTE…).

It looks like CIM is the best standard we have for grid model exchange at the moment, even if it’s not open. A lot of open-source modelling softwares appear to support it, as well as a few of the commercial softwares I use. I’ll keep looking and report back if I find an open CIM equivalent.

Michel


#10

Hi @Miek That all looks very sensible. I forwarded your concerns over pricing to the FSFE coordinator on open standards. A quick look at the IEC bookstore suggests that the CIM suite is circa USD $5000. For a broad take on standards, FOSS, and innovation, try Husovec (2018). HTH, R.

References

Husovec, Martin (18 July 2018). Standardization, open source, and innovation: sketching the effect of IPR policies — TILEC Discussion Paper DP 2018-034. Rochester, New York, USA: Social Science Research Network. doi:10.2139/ssrn.3215769. SSRN 3215769. Open access but registration required.