Italian Transmission System Operator Research Articles

Conceptualization and Experimental Deployment of an Adaptive Synchronized Sensing System for Power Line Thermal Monitoring

Synchronized sensing offered by wide area measurement systems (WAMSs) enables advanced investigations on modern electrical power systems not performable before their advent. One of them is overhead lines (OHL) temperature monitoring, which can be implemented in WAMS industrial domains thanks to the availability of newly accessible sensing information provided by phasor measurement units (PMUs). To accomplish this task, a proper sensing-based integrated intellectualization is necessary in order to face with the major WAMS issues and challenges. In line with these considerations, this paper proposes an advanced computing framework for real-time conductor temperature monitoring of fully transposed OHLs that is able to overcome the aforementioned challenges and issues. The validity and effectiveness of the conceptualized solution is verified via field tests on an Italian transmission line currently in operation. The obtained outcomes led the Italian Transmission System Operator (TSO) to equip its own Energy Management System (EMS) with the deployed solution.

Application of a LiFePO4 Battery Energy Storage System to Primary Frequency Control: Simulations and Experimental Results

This paper presents an experimental application of LiFePO4 battery energy storage systems (BESSs) to primary frequency control, currently being performed by Terna, the Italian transmission system operator (TSO). BESS performance in the primary frequency control role was evaluated by means of a simplified electrical-thermal circuit model, taking into account also the BESS auxiliary consumptions, coupled with a cycle-life model, in order to assess the expected life of the BESS. Numerical simulations have been carried out considering the system response to real frequency measurements taken in Italy, spanning a whole year; a parametric study taking into account different values of governor droop and of BESS charge/discharge rates (C-rates) was also performed. Simulations, fully validated by experimental results obtained thus far, evidenced a severe trade-off between expected lifetime and overall efficiency, which significantly restricts the choice of operating parameters for frequency control.

A generation-attraction model for renewable energy flows in Italy: A complex network approach

In recent years, in Italy, the trend of the electricity demand and the need to connect a large number of renewable energy power generators to the power-grid, developed a novel type of energy transmission/distribution infrastructure. The Italian Transmission System Operator (TSO) and the Distribution System Operator (DSO), worked on a new infrastructural model, based on electronic meters and information technology. In pursuing this objective it is crucial importance to understand how even more larger shares of renewable energy can be fully integrated, providing a constant and reliable energy background over space and time. This is particularly true for intermittent sources as photovoltaic installations due to the fine-grained distribution of them across the Country. In this work we use an over-simplified model to characterize the Italian power grid as a graph whose nodes are Italian municipalities and the edges cross the administrative boundaries between a selected municipality and its first neighbours, following a Delaunay triangulation. Our aim is to describe the power flow as a diffusion process over a network, and using open data on the solar irradiation at the ground level, we estimate the production of photovoltaic energy in each node. An attraction index was also defined using demographic data, in accordance with average per capita energy consumption data. The available energy on each node was calculated by finding the stationary state of a generation-attraction model.

Eco-sustainable routing of power lines for the connection of renewable energy plants to the Italian high-voltage grid

Routing of high-voltage electric transmission lines for the connection of renewable energy-distributed generation plants is a critical issue from an environmental point of view. A standard methodology that accounts for multiple perspectives, influence factors and is able to mediate between weighted constraints can be a useful tool for the regulating bodies that are involved in approval processes. The methodology can be an effective support to increase reliability, save consumers' money and mitigate the unavoidable impacts of the lines on the population living nearby. In this paper we investigate the suitability of a procedure employed by Terna, the Italian high-voltage transmission system operator, to identify the corridors where to route new overhead transmission lines with the lowest environmental impact. The methodology is based on the subdivision of all the relevant constraints dictated by environmental issues and territory legislations in four main classes. A real case study concerning the design and connection of a wind farm placed near Collarmele, in the center of Italy, shows the effectiveness of the proposed methodology.

Bulk indices for transmission grids flexibility assessment in electricity market: A real application

The present paper reviews the concept of flexibility for an application to power systems for operational planning of transmission grid in market environment. The background that makes useful the application of the flexibility notion to power systems is explained. Some general definitions concerning the concept of flexibility in more recent scientific literature are reported. A specific and unique definition of transmission system flexibility in respect of the generation changes is proposed. The mathematical model and the calculation methodology of some bulk system flexibility indices are presented. A dedicated tool in Matlab for their computation is briefly shown in its features. The tool is owned by the Italian Transmission System Operator (TERNA) and is in testing for the flexibility evaluation of parts of the Italian National Transmission Grid. An application of the procedure to a real case is presented and the main results are discussed with the aim of test the validity of the proposed indices.