Zdenek Muller

Zdenek Muller


Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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22 October 2018 in Energies
Verified
Journal Article
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VTValeriya Tuzikova
Valeriya Tuzikova
JTJosef Tlusty
Josef Tlusty
ZMZdenek Muller
Zdenek Muller
In the modern electric power industry, Flexible AC Transmission Systems (FACTS) have a special place. In connection with the increased interest in the development of “smart energy”, the use of such devices is becoming especially urgent. Their main function is the ability to manage modes in real time: maintain the necessary level of voltage in the grids, control the power flow, increase the capacity of power lines and increase the static and dynamic stability of the power grid. The problem of system reliability and stability is related to the task of definitions and optimizations and planning indicators, design and exploitation. The main aim of this article is the definition of the best placement of the STATCOM compensator in case to provide stability and reliability of the grid with the minimization of the power losses, using Particle Swarm Optimization algorithms. All calculations were performed in MATLAB.

30 November 2020 in Energies
Verified
Journal Article
Open access
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VKVladimir Krepl
Vladimir Krepl
Husam I. ShaheenHusam I. Shaheen
Husam I. Shaheen
Ghaeth FandiGhaeth Fandi
Ghaeth Fandi
LSLuboš Smutka
Luboš Smutka
ZMZdenek Muller
Zdenek Muller
SGSafwan Ghanem
Safwan Ghanem
The electric power sector in countries suffering from crises and wars such as Syria, Iraq, Yemen, Libya, etc., is among the most affected infrastructures. Since this sector plays a vital role in the economic growth and in improving people’s quality of life, the post-crisis reconstruction of this sector must take into account the requirements and concepts of sustainable development (SD) in addition to technical and economic considerations. This article discusses the role that renewable energy sources (RES) can play in achieving SD in the post-crisis reconstruction phase of the Syrian Electric Power Sector (SEPS) as a case study. Based on the available data, the study period was chosen from 2005 to 2017 and divided into two periods. In the first period (2005–2010), which is the pre-crisis period, the structure of the SEPS and its main characteristics were described while the adoption of RES solutions and SD concepts were investigated. In the second period (2011–2017), the crisis period, the satiation of the SEPS and impact of the crisis were evaluated. The challenges that faced the adoption of SD concepts and RES solution were also addressed at this stage. Based on analysis and comparison of the available data, several scenarios were discussed to evaluate the role of RES in achieving SD in the post-crisis reconstruction phase of the SEPS. EnergyPLAN software was used for the techno and socio-economic evaluation of these scenarios. Our results emphasize the importance of the adoption of RES solutions in the reconstruction phase, as these can help promote SD concepts (reducing greenhouse gas emissions, protecting the environment, increasing energy efficiency, creating jobs, etc.) and securing the electric supply of the SEPS while enhancing its stability.

30 May 2018 in Energies
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Journal Article
Open access
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Ghaeth FandiGhaeth Fandi
Ghaeth Fandi
IAIbrahim Ahmad
Ibrahim Ahmad
FIFamous O. Igbinovia
Famous O. Igbinovia
ZMZdenek Muller
Zdenek Muller
JTJosef Tlusty
Josef Tlusty
VKVladimir Krepl
Vladimir Krepl
Distributed Generation (DG) has become an essential part of the smart grids due to the widespread integration of renewable energy sources. Reactive power compensation is still one of most important research topics in smart grids. DG units can be used for reactive power compensation purposes, therefore we can improve the voltage profile and minimize power losses in order to improve the power quality. In this paper two methods will be used to accomplish the mentioned tasks; the first technique depends on the reactive power demand change of the proposed network loads, whereas the second technique uses an algorithm to control DG units according to the measured voltage values in the feeders to generate the needed reactive power. Both methods were applied to different scenarios of DG unit positions and different reactive power values of loads. The chosen DG unit is made up of a Type-4 wind farm which could be used as a general unit where it is able to control reactive power generation in a wider range separately from active power. The simulation results show that using these two methods, the voltage profile could be improved, power losses reduced and the power factor increased according to the placement of DG units.

18 December 2018 in Sustainability
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Journal Article
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FIFamous O. Igbinovia
Famous O. Igbinovia
Ghaeth FandiGhaeth Fandi
Ghaeth Fandi
IAIbrahim Ahmad
Ibrahim Ahmad
ZMZdenek Muller
Zdenek Muller
JTJosef Tlusty
Josef Tlusty
Installing a synchronous condenser (SC) onto an electricity grid can assist in the areas of reactive power needs, short-circuit strength, and, consequently, system inertia and guarantees better dynamic voltage recovery. This paper summarizes the practical potential of the synchronous condenser coordinated in an electric-power network with participating wind plants to supply reactive power compensation and injection of active power at their point of common coupling; it provides a systematic assessment method for simulating and analyzing the anticipated effects of the synchronous condenser on a power network with participating wind plants. A 33-kV power line has been used as a case study. The results indicate that the effect of the adopted synchronous condenser solution model in the MATLAB/Simulink environment provides reactive power, enhances voltage stability, and minimizes power losses, while the wind power plants provide active power support with given practical grid rules.

3 June 2021 in Energies
Verified
Journal Article
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LVLavr Vetoshkin
Lavr Vetoshkin
ZMZdenek Muller
Zdenek Muller
The paper investigates the stability of a power system with synchronverters. A synchronverter is a control strategy for voltage source converters that introduces virtual inertia by mimicking synchronous machines. The authors picked a commonly known IEEE 9 bus and IEEE 39 bus test case systems for the test case studies. The paper presents the power system’s modal analysis with Voltage Source Converters (VSCs) controlled as synchronverters, vector control, or Rate of Change of Frequency-based Virtual Synchronous Generator, thus comparing different approaches to VSC control. The first case study compares selected control algorithms, the IEEE 9 bus system, with one VSC in the paper. The results demonstrate the benefits of synchronverters over other control strategies. The system with synchronverters has a higher minimal damping ratio, which is proven to be the case by numerical simulations. In the second case study, the effects of virtual inertia placement were investigated. The computations showed that placement is indeed important, however, the control strategy is as important. Besides, the system with synchronverters exhibits better stability characteristics. The paper demonstrates that the application of synchronverters is feasible and can meet the demand for algorithms that bring the benefits of virtual inertia.

6 September 2019 in Energies
Verified
Journal Article
Open access
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IAIbrahim Ahmad
Ibrahim Ahmad
Ghaeth FandiGhaeth Fandi
Ghaeth Fandi
ZMZdenek Muller
Zdenek Muller
JTJosef Tlusty
Josef Tlusty
The increased penetration of renewable energy sources in the electrical grid, due to the rapid increase of power demand and the need of diverse energy sources, has made distributed generation (DG) units an essential part of the modern electrical grid. The integration of many DG units in smart grids requires control and coordination between them, and the grid to maximize the benefits of the DG units. Smart grids and modern electronic devices require high standards of power quality, especially voltage quality. In this paper, a new methodology is presented to improve the voltage quality and power factor in smart grids. This method depends on using voltage variation and admittance values as inputs of a controller that controls the reactive power generation in all DG units. The results show that the controller is efficient in improving the voltage quality and power factor. Real data from an electrical network have been used in the simulation model in MATLAB Simulink to test the new approach.