This paper gives an insight in synchrophasor technologies and proposes an overall framework for estimating power transmission line parameters, by employing synchronous phasors in real time. Based on estimated line parameters, the average line temperature and the sag of selected spans can be calculated and utilized for dynamic thermal rating applications for increased power transfer.

The growing penetration of renewable energy sources (RES) and distributed energy resources (DERs) has introduced new challenges in power system stability voltage regulation, and congestion management. Therefore, effective TSO-DSO coordination is crucial for addressing these operational complexities and ensuring a reliable and flexible grid. This paper examines critical coordination domains, including voltage control, congestion management, frequency control, operational planning, system restoration, and ancillary services. We evaluate three principal coordination models—TSO-managed, DSO-managed, and hybrid TSO-DSO approaches—alongside six market schemes that define flexibility service procurement processes. Through analysis of centralized, distributed, and hierarchical technical solutions, we identify structural, regulatory, and technical gaps limiting effective coordination. Our examination of existing initiatives reveals that many projects treat balancing and congestion management as separate processes rather than integrated functions, overlooking potential synergies. Integrating these functions could enhance market efficiency, reduce system costs, and improve grid reliability, particularly within Nordic balancing market frameworks. The paper concludes by recommending innovative technologies, market designs, and operational strategies to enhance grid resilience, optimize DER integration, and promote efficient flexibility markets across transmission and distribution networks, contributing to the development of sustainable, reliable power systems.

Significant power sector developments beyond 2020 will require changing our approach towards electricity balancing paradigms and architectures. Presently, new electricity balancing concepts are being developed. Implementation of these in practice will depend on their timeliness, consistency and adaptability to the market. With the purpose of tailoring the concepts to practice, the development of a balancing market is of crucial importance. This article deals with this issue. It aims at developing of a high-level economically efficient market design for the procurement of system balancing products within the Web-of-Cells architecture. Literature and comparative analysis methods are applied to implement the aim. The analysis results show that a more efficient balancing capacity allocation process should be carried out in a competitive way with closer allocation time to real-time, especially with increased penetration of renewable energy sources. Bid time units, the timing of the market, procurement and remuneration schemes as well pricing mechanisms are the most decisive elements of the market. Their respective advantages and disadvantages are analyzed in the article, as well as their analysis is done against the selected assessment criteria. The results of the analysis show that seeking to improve the operational efficiency of the market, the sequential approach to the market organization should be selected and short-term market time units should be chosen. It is expected that price efficiency could be improved by establishing an organized market where standardized system balancing products should be traded. The balance service providers, who own capital expenditures (CAPEX) sensitive production units, should be remunerated both for the availability of balancing capacities and for their utilization. Uniform pricing rule and cascading procurement principal should be applied to improve the utilization efficiency.

This paper investigates the regulatory rules of market transparency which could be applied within the wholesale electricity market and market for frequency and voltage control in the Web-of-Cells (WoC) decentralized power control architecture, which has been developed in the ELECTRA Project to respond the challenges and needs of the future power system (2030+). In this decentralized functional architecture for frequency and voltage control, the European Union (EU) power grid is divided into grid control areas, i.e., cells, which are defined as portions of the grid having adequate monitoring infrastructure and local reserves capacity, allowing voltage and balancing (frequency) problems to be solved at cell level, under the responsibility of a Cell System Operator (CSO) (present Distribution System Operator (DSO)/Transmission System Operator (TSO)). In order to foster the practical realization of the WoC-based architecture, the related wholesale electricity market and market for frequency and voltage control are proposed considering the competitive market principles, including transparency. The critical review of the existing EU regulations dealing with this issue suggests respecting the valid provisions on market transparency while tailoring them into the WoC-based architecture. Moreover, in order to take into account the WoC peculiarities, a set of integrations to the current regulatory rules is also proposed, addressing: (1) disclosure of information in respect to attributes of emerging technologies such as renewable energy sources (RES), distributed energy resources (DER), storage; (2) provision of generation and load forecast information; (3) process of procurement of flexibilities; (4) retail market transparency; (5) disclosure of privacy-sensitive household attributes; and (6) disclosure of information on market for frequency and voltage control.