A New Monitoring Tool to Increase Usable Network
Transfer Capacity with Existing Assets
(2015)Abstract
This proposed paper focuses on the criteria that need to be met to allow network operators to effectively
use Dynamic Line Ratings (DLR) and its forecast in real-life operations. This technology actually allows a
higher utilization of existing lines with a higher level of security. Different pilot projects in Europe and around
the world have proven the DLR technology works in the field and many papers within CIGRE and other
organizations highlight those results. Even harsh weather conditions encountered in Middle-East climate
can be effectively monitored, as sag monitoring guarantees conductor-to-ground clearance. However, focus
is now shifting to how this technology can be put to best use: where it makes sense and how the results
should be used to maximize the benefits while at the same time reducing the operational risks. The paper
will highlight the experience Elia, the Belgian TSO, and Coreso, the TSOs' coordinator at the European level,
have had regarding those questions.
In the context of the rapid growth of electricity consumption and RES development, DLR allows to close
the gap between congestions appearances and the effective commissioning of new pieces of network that
takes between 5 and 10 years. But it can do better. Indeed, most decisions regarding network operation and
electricity market are taken many hours/days in advance, therefore if DLR is to influence these decisions, a
reliable forecast of the dynamic rating values is required. This is similar to the need for the forecast of wind
& sun production that allows the safe integration of those intermittent energy sources into the power system.
Within the EU-funded FP7 Twenties project, the University of Liege, Belgium, together with Ampacimon have
developed such a capability. Two-day ahead DLR forecast has shown an average capacity improvement of
more than 10% over seasonal rating with 98% confidence. The prediction interval may further be adjusted
to operational needs.
The paper will further highlight 3 years of operation of two critical lines located near the North Sea and
impacted by the connection of off-shore wind resources using intra-day and day-ahead forecasting of DLR.
It will answer the following questions: what were the usable operational gains? What were the lessons
learned? How was DLR integrated in the operational tools & processes ?
The conclusion of those experiences shows that innovative solutions emerge from two-day ahead ampacity
forecast provided by DLR. They release their full operational capabilities when combined with controllable
assets (FACTS, PST, curtailment) and stability monitoring (PMUs) within integrated solutions. They hence
achieve the objective of increasing the efficiency of the existing network and help integrate intermittent
renewable energy sources in a safe and economical way.
