Michal Kolcun

• Technical University of Košice

The technique of estimating the expected decrease in electricity consumption from the grid and using PV energy for the taken load schedule based on archival data for 5 years is refined. With full self-consumption (SC), the reduction of consumption from the grid can be increased by 9.5%–30.7% for a year according to the rated PV power. Consumption s...

Ground wires are bare conductors which serve to protect the power line from the lightning strike. This article deals with the calculation of the series impedance of the 110 kV overhead power line with one ground wire. The article examines the effect of the ground wire on the series impedance of the 110 kV power line compared to the same power line...

This article deals with the analysis of a day-ahead generation diagram in specific part of a power network with renewable energy sources. As a renewable energy source a photovoltaic power plant was chosen. Input data for a day-ahead analysis was obtained from the database of previous measurement that was realised on the existing configuration in of...

An overhead power line is a structure used in the electric power system to transmit electrical energy. The performance of overhead power lines depends on their parameters. There are four basic electrical parameters of power lines: resistance, inductance, capacitance, and shut conductance. The paper focuses on the calculation of the series impedance...

This paper describes modelling, simulation and sizing of hybrid renewable system for pumping of soaking water from closed mine Bankov in Košice and different electrical power load time management strategies for using electricity. There will be analysed three different time management strategies of electrical load and how they affects to cost and si...

This paper discusses the problem of reliability of the Polish medium voltage power lines. It presents the benchmarking of power lines and values of SAIDI. The probability density distribution of the medium voltage lines length as well as selected indicators of the MV power lines reliability, being operated by the distribution companies under test,...

The stability of the ferrofluid (FF) subjected to the electric field is crucial for the application in high voltage (HV) technology. There are several cases where the fluid interacts with solid interfaces. We examined experimentally FF drop on a glass surface. The drop was exposed to the steady electric field. During tests the suspended particles s...

This paper focuses on solid component separation from flowing gases by alternating current (AC) electric field. Separators are often used for solid and liquid aero dispersing component separation by direct current (DC) electric field. A high voltage transformer and high voltage rectifier is used to generate DC electric field. The semiconductor rect...

The increased demand for power transfer in combination with environmental and economic issues which set constraints to building new lines, force the implementation of new technologies into the existing system in order to improve its power capability. This paper investigates the use of specific FACTS devices and WAMS systems to maximize total transf...

The Construction of new international power lines is a very expensive and timeconsuming task. The use of specialized equipment that can increase the Total Transfer Capacity can replace the need to construct new lines. One such device is a Phase Shift Transformer (PST). By optimal distribution of power flow on transmission lines we could increase TT...

This work proposes the generalization of models for excitation systems. Thirteen models according to IEEE standard are reduced to three main types by the development of a common universal excitation control model. The original IEEE division of exciter types into alternator-supplied rectifier and static excitation system is rearranged into non-contr...

This paper deals with design and simulation of hybrid system which consists of photovoltaic power plant, battery energy storage and load. It is used for power supply of public lighting based on renewable energy. Parameters of public lighting are inspired by real situation in small Slovak village. Hybrid system was designed and sizing optimization o...

This paper discusses the implementation of the renewable energy sources and the energy storage system to the smart grid by means of simulating toolkit of Modes. The output curve of photovoltaic and wind power plant is also the part of this paper. This paper analyses the difference between residential and commercial load. The test system was made in...

This article deals with sizing of hybrid renewable sources applications that are suitable in remote areas where grid connection is unavailable or connection to grid is expensive. Depending on the size of installed capacity of each photovoltaic, wind power and small water power plant, such a system can be used to power small systems with hundreds wa...

This paper deals with modelling of a photovoltaic power plant in combination with a battery energy storage system and their cooperation in order to better renewable energy utilization at local level. In this paper, the model of grid on a hybrid system that is formed by the battery energy storage system, a photovoltaic power plant, a utility grid an...

This paper deals with a better integration of renewable energy sources into the conventional grid and also into the microgrid, which is a basic part of future smart grid concept. Renewable energy sources produce variable and intermittent power output what causes a problems with power quality and power system stability. Some types of energy storages...

The implementation of microgrids gets into strategic dimensions for further directions of power engineering. There are concepts that were closely investigated by numerous of experts worldwide. This paper describes the operation principles of microgrid design considering the requirements arising from implementation of renewables. It proposes the con...

Due to the reduction of investment and space requirements for the construction of new overhead power lines, a one multi-system solution can be chosen in the case of overlapping lines even in case of more different voltage levels. On the other hand, these lines, affect themselves by their electromagnetic fields which may cause increased level of vol...

This paper deals with the problematic of the actual short-circuit power determination in real conditions. Presented principle of a real value of short-circuit power determination in arbitrary node of the power system is based on the measurement of one cycle RMS voltage and current changes. Described should be useful for determination of short-circu...

This paper deals with creating a mathematical model of ideal photovoltaic module. The performance of the model is demonstrated with output characteristics which also show the effect of changes in temperature and solar radiation on the output parameters of cell, module, and field. The model is realized in Matlab/Simulink environment due to frequentl...

Batteries in transmission grids can provide ancillary network services, such as primary frequency response, voltage control in network nodes or back up power. The Battery Energy Storage Systems (BESS) is often the most limiting factor within their more extensive usage for the frequency control. Because of this it is necessary to adjust the system c...

Most important issue in electricity markets is the maximizing of Net Transfer Capacity (NTC). This paper presents an approach for the placement of one Unified Power Flow Controller (UPFC) in interconnected power systems to increase NTC. Detailed analysis is presented for Slovak - Czech and Slovak - Hungary interconnection in Central East Europe net...

Power systems nowadays are becoming more complex, also with constantly growing electricity consumption. A new phenomenon of renewable energy sources connection into power system is also influencing the power system complexity. This paper deals with the possibilities of usage of software tools for power system studies in more complex way. The modeli...

This paper analyzes particular cases of active power and frequency control strategies in island operation when a part of the system is electrically separated from the main interconnected system. This operation condition occurs rarely on a transmission system level; however, the control systems on all levels should be adjusted accordingly and transm...

The possibility of dynamic energy storage such as auxiliary function FACTS regulator offers to control flows of active and reactive power in an attachment point to the system. Dynamic control of active and reactive power is running independently from each other. Reactive regulation power provides voltage control and network stability with a huge dy...

This paper deals with design, calibration, experimental implementation and validation of cost-effective smart metering system. Goal was to analyse power consumption of the household with the immediate availability of the measured information utilizing modern networked and mobile technologies. Research paper outlines essential principles of the meas...

The paper presents investigation on the magnetic fluids that are stable colloidal suspensions of single-domain magnetic particles in a liquid carrier of dielectrics nature. Studies were made on the electric field vs. current density, e.i. E-J characterization commonly observed in insulating liquids under uniform low electric or magnetic fields. Hig...

Zinc oxide-based extrinsic composite was investigated. The sample was selected from a series of components of one production batch, prepared by standard sintering technology. The content of extrinsic elements in ZnO base was determined by SEM. Van der Pauw method with four-point electrode fixture was used for study of conducting phenomena in square...

Large-scale power systems operation is faced with many challenges. One of many criteria, which should be fulfilled are stability criteria. Interconnecting separated power systems into interconnected network results in large system complexity, and therefore mixed influences from one power system to another part. Also, new devices are introduced to i...

This paper discusses the influence of growing amount of electrical energy produced in photovoltaic (PV) power plants to power system stability, according prognosis of PV growth for year 2020. A few different scenarios were created according to PV development outlook documents listed in references. The simulations were performed in MODES on the cont...

This paper deals with the short-term active power consumption of electric arc furnace (EAF) as an example of variable and asymmetrical three-phase load. The aim of this paper is to describe the phenomenon of negative active power consumption effect in some phase of three-phase power system in case of asymmetrical and variable load in real condition...

This paper discuss about the influence and problems caused by integration of renewable energy sources to the power system. Paper analyzes the problems of undesirable power flows that results from difficult predictability of production from these power plants. These impacts were modelled by means of program MODES on standardized power system of IEEE...

This paper describes the impact of renewable energy sources on stability of EWIS transmission system. EWIS is modeled in simulation program MODES. This model consist of 25 control areas, and includes photovoltaic power plants with 18, 7 GW of installed capacity and wind power plants with 15, 9 GW. This article examines the effectiveness of support...

This paper describes the impact of regulators on the different types of short circuits currents of power system. To preview the effects of regulators of the size of various types of short-circuit currents were modeled large system. Each generator contains AVR controller. The impact of these regulators is described in this article.

Zinc oxide-based extrinsic composite was investigated. The sample was selected from a series of components of one production batch, prepared by standard sintering technology. The content of extrinsic elements in ZnO base was determined by SEM. Van der Pauw method with four-point electrode xture was used for study of conducting phenomena in square-s...

The paper presents research on unipolar characteristics of ZnO ceramics. Dielectric response analysis is generally known method to characterize electrical properties of materials. It becomes important method for non-destructive testing. Recently, the possibilities and limitations of this method to reflect the deterioration processes due to thermal...

The paper describes anomaly origination on current or voltage characteristics in time of positive potential on small curvature radius electrode rod against plane electrodes. An anomaly phenomenon occurred in the narrow voltage area in a high non-homogenous electric field close to the electrode (E > 107 V m−1). A mathematical – physical analysis of...

The paper focusing on topical issue related to a integration of bulk wind production into a power supply mix. Target is to propose comprehensive approach that covers quasi-random wind series simulation that considers particular regional conditions with its seasonality variation. Moreover, in context of the paper is proposed advanced approach for si...

A series of un-doped borate glasses with Li2B4O7, LiKB4O7, CaB4O7, and LiCaBO3 compositions of high optical quality and chemical purity were obtained from corresponding polycrystalline compounds using standard glass synthesis and technological conditions developed by authors. The optically thermopoled second harmonic generation (SHG) effect in the...

This paper deals with measuring of the shielding effectiveness of electromagnetic field, depending on gradually drying out. In today's tough economic times people are forced to save, what is a trend of thermal insulation of buildings. One of the materials used for insulation is polystyrene EPS 70F. It is this type of polystyrene was aimed measuring...

This paper deals with measuring of shielding effectiveness of electromagnetic field. The measurements were focused on measuring of shielding effectiveness in the range of high frequencies from 1 GHz to 10 GHz. The measured object was a wooden board Medium Density Fiberboard (MDF12) with a thickness 12 mm.

Operation of large-scale power systems became more complicated in these days, especially when stability, safety and economic criteria for power system operation should be fulfilled. Stability of power system is becoming a one of the most severe problems in power system operation, mainly due to unpredictable circular power flows from renewable sourc...

This paper deals with the problematic of the actual short-circuit power determination in real conditions. The principle of short-circuit power determination in arbitrary node of the power system is described with the use of steady-state power system model. Described considerations are based on the determination of short-circuit power in the nodes e...

In this paper is describing the simulation of electromagnetic field in the program ANSYS. Field simulations are used to study the effects of various materials on its distribution. (Simulation the influence of shielding materials to the distribution of electromagnetic field).

This paper deals with the simulation of electromagnetic field and the influence of shielding material to its distribution. As a shielding material was selected copper alloy.

The quality as well as reliability of electrical energy transmitted to consumers is one of the main parameters of successful operation of the power system. The problem of power oscillation damping in the power system is solved using power system stabilizer (PSS) which use additional voltage regulation loops. The searching of optimal coefficient's c...

The aim of this paper focuses on the analysis of system spot price formation factors formed by the organized electricity market operated by the Nord Pool Spot power exchange. Analysis and statistical evaluation of historical data has been performed in order to identify and rank factors according to the price impact as well as to analyze their seaso...

The article is related to a topical issue of the newly-arisen market power phenomenon in the electric power industry. The authors point out to the importance of effective instruments and methods for credible estimation of the market power on liberalized electricity market as well as the forms and consequences of market power abuse. The fundamental...

The article deals with possibilities of the thyristor controlled series capacitor (TCSC) to control power flows control in interconnected electrical power systems. The main goal is to describe the working principle of TSCS and its possible use in the transmission system (TS) and advantages and disadvantages of using of such equipment if the electri...

The significant growth of installed power capacity of renewable energy sources (RES) in last few years may cause incidental disturbance of power balance in the power system. Because of the RES this disturbance may be caused on the production side of the power balance equation. The power production from RES nowadays is 18 per cent of the total consu...

Abstrakt: With reference to interconnected transmission networks operation, the actual tendencies of the electric power systems cooperation have the following character: increasing electric energy transits on big distances in case of the participation of more electric power systems in transit, increasing capacities of the electric energy internatio...

The article deals with possibilities of the phase shifting transformer (PST) to control power flows in interconnected electrical power system. The main goal is to describe the working principle of PST and to find out an influence of installation of PST on international lines and losses of the transmission system (TS) of the Slovak Republic.

Temperature and the resulting thermal behavior of electric power generation and distribution equipment and industrial electrical systems and processes are the most critical factors in the reliability of any operation or facility. Temperature is by far the most measured quantity in any industrial environment. For these reasons, monitoring the therma...

This study of connecting the dispersive source to the MV power line kept the Operation Standards of Distribution Systems. The project of the electric part solves an electric connection, a switching station and electric protections. The electric protection system must be a selective one, with engine protections. Primary tests are recommended for tes...