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Today, incentive policies have been proposed to contribute to small consumers in the market to improve network security. In this paper, the simultaneous competition of small consumers in the form of independent firms and power plants in the new market structure is modeled and the impact of competition of these firms on the behavior of generation firms and network costs is investigated. Given the multiplicity of consumer presence in this market and the rumor that this may slow down the market settlement process, the effect of imposing restrictions on a strategy change for all participants has been investigated.

A classification of volume-exchange towers with loose packing used in chemical, petrochemical, oil refining, and food enterprises is proposed. A critical survey of the most typical designs of volume exchange towers with loose packing as well as, directly, elements of loose packing is carried out.

The results of an experimental study of a high-energy spark ignition system with self-stabilization of the discharge current are presented. A description of the physical principle that provides self-stabilization is given. The effect of a high-speed gas flow on such parameters of a spark discharge as discharge current, resistance of the discharge gap, voltage across the spark gap, the energy input into the spark discharge, the duration and efficiency of the input is studied.

Abstract A model is developed to investigate the effect of energy investment on economic growth under a set of simplifying assumptions. The economy is treated as a two sector aggregate; the energy sector and the rest of the economy, whereas the model describing the energy-economy interaction is linear to the differential changes of the variables, adaptable to structural evolution and requires a modest amount of data for initialization. It can be used in a single stage or an iterative mode to produce outcomes for the short and medium run. The analysis reveals that energy productive investment has had an impact on the rate of formation of the non-energy capital stock and subsequently on economic growth. These effects appear amplified under a regime of increasing energy price.

This work discusses composite coatings obtained by electro-spark alloying and self-propagating high-temperature synthesis. It has been established that the generated composite coatings consist of titanium carbides, which are uniformly distributed in the metal matrix. The titanium carbide grain sizes are in the range of 0.1–4.0 μm. The coarse grains of titanium carbide in the coating consist of disperse carbides with sizes of less than 1 μm. The study of the structure of the composite coatings in friction tracks has demonstrated that the generated coatings possess high wear resistance.

The objective of the paper is to present a -t stability index that can be used for the security assessment of electric power systems. This index provides an evaluation of the system securitylevel by considering t he values of the accelerations and kinetic energies of the generators, after the occurrence of a large disturbance. The derivation of the index is based on the pattern recognition principles and the fuzzy sets theory. The results that are o btained f rom the application of the i ndex are illustrated by the stability analysis of two power systems. The first is the CIGRE test system, while the second is the Hellenic Interconnected System.

Abstract The objective of the paper is to describe an expert system methodology which has been developed for determining the most likely nature, cause and expected duration of failures occurring in power system components. The inference engine task is based on Bayes' theorem and the knowledge acquired during the study of the historical outage records of the power system. This study allows the expected values of outage rates and durations to be evaluated for all component categories and groups. This expert system methodology can be a very useful tool with which to determine the most likely expected duration of a failure and to select the most appropriate operational actions to be performed. An example of application of this methodology to failures occurring in power transformers is also included.

The microgrid (MG) has emerged as part of the technological transition to smart grids. The MG can operate in two modes: connected to a distribution network or in an isolated stand-alone way. When the transition to island mode occurs, the M G must operate in a stable, reliable, and resilient way. In this context, the distributed energy resources (DERs) that are part of the M G must respond optimally to guarantee dynamic voltage stability (DVS) and to improve operational resilience. Under resilient contingency conditions, the voltage stability and reactive power control of the MG is severely compromised. Therefore, even though DERs based on smart inverters operate according to the low-voltage ride-through (L VRT) requirements stated at the IEEE Standard 1547–2018, it is not enough to supply the reactive power deficit. Thus, this paper aims to include FACTS (flexible ac transmission systems) type compensation devices, particularly a static var compensator (SVC) that operates in coordination with DERs of the MG. The results obtained are satisfactory, and it is shown that the smart inverters used for the DERs and the SVC device operating with a coordinated control strategy improved the DVS, allowing the control of the reactive power supply and granting an adequate level of operational resilience in the isolated MG.

The paper deals with the management of multi-connected objects with multiple inputs and outputs, the so-called MIMO (multi-input multi-output) systems. Special attention is paid to the adaptation of SISO (single-input single-output) technologies to control MIMO systems. For this, it is proposed to carry out dynamic decoupling of control channels using a pre-switched on cross-link compensator. For the technical implementation of the cross-link compensator, a method is proposed for approximating its transfer functions, which makes it possible to significantly reduce their order. All conclusions are confirmed by the results of mathematical modeling of output processes in closed and open control systems.