The paper deals with the main prospects and challenges of radical transformations of electric power systems (EPSs) with changes in their structure and properties conditioned by wide use of innovative energy-related technologies and digitalization and intellectualization of system operation and control. Structural trends of EPS development are the focus of the analysis. Consideration is given to changes in EPS properties driven by the use of new technologies, to the problems of system flexibility and to its enhancement. EPS “resiliency” and “survivability” notions are subjected to comparison. The main factors favoring the formation of future EPSs to cyber-physical systems are discussed. Objective trends of EPS control and protection system development are under consideration.

Energy systems including electricity, heat/cooling, and gas supply systems represent a very important part of the infrastructure in Russia. This paper presents a general framework of integrated energy systems. Elements of the concept of integrated energy systems are suggested. The explanation of the concept elements is given as a three-layer structure of integrated energy systems in three dimensions. The problems of integrated control of electric and heat networks deal with issues of combined calculation of operating conditions of the electric and heat networks integrated in the intelligent energy supply system. A mathematical description of the problems is presented. The results of two illustrative case studies are shown and explained. The first case study represents research on an emergency situation at the supergrid level of the energy system layers after an accident on a pipeline of the gas transportation network. The second case study represents research of interdependency of power and heat supply minigrids in emergency conditions on the example of a city district. Preferable future work is discussed.

The increase in the use of converter-interfaced generators (CIGs) in today’s electrical grids will require these generators both to supply power and participate in voltage control and provision of grid stability. At the same time, new possibilities of secondary QU droop control in power grids with a large proportion of CIGs (PV panels, wind generators, micro-turbines, fuel cells, and others) open new ways for DSO to increase energy flexibility and maximize hosting capacity. This study extends the existing secondary QU droop control models to enhance the efficiency of CIG integration into electrical networks. The paper presents an approach to decentralized control of secondary voltage through converters based on a multi-agent reinforcement learning (MARL) algorithm. A procedure is also proposed for analyzing hosting capacity and voltage flexibility in a power grid in terms of secondary voltage control. The effectiveness of the proposed static MARL control is demonstrated by the example of a modified IEEE 34-bus test feeder containing CIGs. Experiments have shown that the decentralized approach at issue is effective in stabilizing nodal voltage and preventing overcurrent in lines under various heavy load conditions often caused by active power injections from CIGs themselves and power exchange processes within the TSO/DSO market interaction.

This paper deals with actively studied terms “flexibility” and “resiliency” of electric power systems (EPS). Definitions and content of these new fundamental EPS properties are analysed. Objective trends in development of EPS with regard to these properties are discussed. Possible measures for improving flexibility and resiliency of EPS are suggested.

The paper is concerned with the coordination of interaction between various types of consumers and a power company to manage electricity consumption by using the adverse selection model based on contract theory. There are several power companies competing in the electricity market according to the Bertrand model. A method is proposed for load curve optimization by different types of consumers and a power company. Moreover, the types of consumers are identified and distinguished. The utility functions constructed for them describe the real situation rather well, and allow the implementation of a system of incentives for load curve optimization (load shifting from a peak time of the day by bounded rational consumer). The prices in rates providing a separating equilibrium are determined.

The paper provides an overview of spectral and modal analysis methods for studying the stability of electric power systems (EPSs) and their control. Consideration is given to theoretical grounds of the methods and to the experience of their application for detecting the heterogeneity of the systems’ structure, identifying the coherency of generators’ motion, simplifying the mathematical model of the dynamics of EPSs, assessing their small-signal stability, and selecting the control actions to ensure it. The analysis of sub-Gramians for studying the EPS stability and other new directions in the development of the modal approach are discussed.