Michal Kolcun

Integration of renewable energy sources to the power system

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 39 bus System. The difference between sunny and cloudy days is compared in graphs and there is calculated that difference in percentage. Variability of wind affecting the wind power plants is also plotted in graphs. Overloading the power lines and transformers cause their outage and the imbalance between production and consumption, what shows the output of simulation.

Impact of renewable energy sources on stability of EWIS transmision system

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 services in Slovak power system.

Design and simulation of hybrid system for public lighting power supply

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 of each element was performed based on public lighting data, typical load curves and weather conditions in a locality. For this purpose, Homer software was used. Subsequently, system was modeled in Matlab/Simulink and its behavior under real conditions during random day in a year was observed to verify design correctness. Results from both simulations were compared and evaluated.

Influence of photovoltaic power plants on the power system to the prediction for year 2020

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 continental Europe power system model which was upgraded to adapt to the grid topology predicted for year 2020.

The effect of negative active power consumption of asymmetrical and variable load represented by EAF

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. The theoretical example of the negative power consumption in special case is also presented in this paper. The results of two sets of active and reactive power measurements during one duty cycle of the small EAF is also presented in this paper.

The implementation of an ideal photovoltaic module in Matlab/Simulink using simpowersystems toolbox

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 frequently using and complexity of this software.

Benchmarking the reliability of medium-voltage lines

Abstract 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, are also introduced. The analysis is based on the actual MV lines and uses the nonparametric method of kernel density estimation.

Transformer use for active power flow control in the electric power system

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.

Solution of transient phenomena during the connection of the photovoltaic power plants

This paper deals with the solution of transient phenomena during the connection of the photovoltaic power plants. There was investigated the impact of the failure of current protection for renewable energy sources during the network disconnection. There was verified the possibility of network operation during the islanding operation. Failure of network protection represents the significant hazard for employees of distribution system operator so it is necessary to solve the accurate current and voltage values during the connection of particular renewable energy sources.

Utilization of energy storages in low voltage grids with renewable energy sources

This paper deals with problems which occurs in low voltage grid in case of high renewable energy penetration, especially with photovoltaic power plants. Also simple way how to utilize energy storage to address these problems is proposed and simple charge/discharge strategy was designed for energy time shifting and capacity firming. Simulation model in Matlab Simulink was developed and two scenarios based on real data were simulated in order to strategy verification. Results are discussed and evaluated, and also some improvements are suggested.