In February 2014, a severe icing storm hit Slovenia and caused damage in order of 8.5 million € only on the power transmission network. In cooperation with Milan Vidmar Electric Power Research Institute (EIMV) and Slovenian Environment Agency (SEA), we developed and validated a DTRi (Dynamic Thermal Rating - icing) model, which was implemented as a prototype system for operative forecasting and prevention of icing on high voltage transmission lines.

The model considers a dynamic heat generation due to the Joule losses within the conductor and heat exchange with the surrounding in terms of convection, radiation, evaporation, rain impinging and solar heating and it was coupled with national meteorological weather forecast model Aladin and implemented into the Slovenian transmission system operator ecosystem.

We have validated the prototype system with measurements on an experimental site and through reconstruction of two real cases, on 1.2.2014 and 5.1.2016 on Beričevo-Divača line. Since the results of the study were promising, the customer decided to promote the system into the operative SUMO environment. For this purpose, we also obtained additional funding from EU FP7 TETRACOM project.

The whole DTRi system comprises the back end computing the physical model, middle end handling outputs from backend and communicating with SUMO, web front end providing users appealing control over the standalone executions, and alarm processing logic that decides how and when the model will be executed. DTRi can run in two modes, i.e. as standalone software and as an embedded system within the SUMO framework, which is a heterogeneous collection of subsystem from different vendors that was developed

to increase safety and security as well as the capacity of the existing transmission network. Its core is the integration platform, SUMO BUS, which is an enterprise integration bus, used for orchestrating the subsystems and facilitating data exchange between them. The communication between SUMO BUS and the subsystems is based on web services. More precisely subsystems communicate with the bus via SOAP/HTTP interfaces. This technology enables different subsystem vendors to quickly and efficiently connect their subsystems using standardized and open means of communication and exchanging data. For example, SUMO allows different Dynamic Thermal Rating (DTR) vendors to be incorporated into the system, each serving a different part of the grid. Currently there are 17 services implemented. They are providing approximately 115 methods to the clients (subsystems). System’s internal state is held in a relational SQL database. The DTRi system is in operational use in the Slovenian transmission network since 2016. The last major upgrade has been implemented in 2021.

Partners

Jozef Stefan Institute (JSI)

Elektroinštitut Milan Vidmar (EIMV)

Slovenian Environment Agency (SEA)

P-Lab team

Funding

Related publications