ASSESMENT OF DAMAGE OF SOLAR HETEROJUNCTION a-SiC/c-Si INDUCED BY NEUTRON RADIATION

<span style="font-family: 'Times New Roman',serif; font-size: 10pt; -ms-layout-grid-mode: line; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-GB; mso-fareast-language: EN-US; mso-bidi-language: AR-SA; mso-bidi-font-style: italic; mso-bidi-font-weight: bold;" lang="EN-GB">Amorphous silicon carbide is known as a material resistant except others influences also against radiation. This study investigates the effects of neutron radiation on electric characteristics (<em>I</em>-<em>V</em> characteristic, impedance spectra and obtained dynamic parameters of AC equivalent circuit) of solar cell a-SiC/c-Si heterojunction structure. The heterojunction structure was irradiated using neutrons with neutron fluence 10¹³ cm^-2. Existence of neutron induced structural defects, which could be introduced within semiconductor structure of heterojunction, has been illustrated using DC and AC analysis. </span><span style="font-family: 'Times New Roman',serif; font-size: 10pt; -ms-layout-grid-mode: line; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA; mso-bidi-font-style: italic; mso-bidi-font-weight: bold;" lang="EN-US">The structural defects induced by neutron particles radiation affect mainly trapping mechanism. The process results in the changes of electronic elements included into proposed equivalent circuit.</span>

Changes of Insulation Properties of Photovoltaic Cables Caused by Ageing Treatment

<span style="font-family: 'Times New Roman',serif; font-size: 10pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-US">An important part of the photovoltaic power plants are cable systems. The dielectric properties of cables, reliability and durability depend on quality of production processes, operating conditions and degradation factors, as well. Expected lifetime of cable systems is more than 20-30 years in general. Their failure free operation and long-term stability of properties has a direct impact on the economic return of the investments. According to our experiences the tests in compliance with valid standards are not adequate to verify real life time during operation. Photovoltaic cables intended for use in outdoor applications for the connection between the solar panels and possible connection between panels and inverter were chosen for our experiments. <span style="-ms-layout-grid-mode: line;">The changes </span>of insulation resistance and breakdown voltage caused by some degradation factors, mainly water, are presented. This research was inspired by real failure in operation.</span>

Simulation Model of Hybrid Shunting Locomotive

The paper describes the simulation model of the hybrid shunting locomotive. The hybrid drive consists of the diesel engine supplemented with lithium batteries. The simulation model is created in order to analyse energy flows, determine influence of the component proper size and control strategy.

ANALYSIS OF SUPPORT SCHEMES AND THE POSSIBILITIES OF SETTLEMENT OF THE BALANCE OF ELECTRICITY GENERATED FROM RENEWABLE ENERGY SOURCES

<span style="font-family: 'Times New Roman',serif; font-size: 10pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-GB; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-GB">Support for electricity produced from renewable energy sources is a key priority for the European Union due to reasons of security and diversification of energy supply, environmental protection, sustainable development, and because the use of electricity from renewable sources is an important part of the measures necessary to comply with the Kyoto Protocol. The article is also focused on several options settlement balance between the producer and supplier of electricity produced from renewable energy sources.</span>

Design of a Dispensing CNC Device

<span style="font-family: 'Times New Roman',serif; font-size: 10pt; -ms-layout-grid-mode: line; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-GB; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-GB">This article deals with the design and practical realization of a CNC device designed for the application of viscous materials, such as a thermal conducting paste. Paste is used for effective heat transfer what is essential in switched mode power supplies. However, its application on surface can be an issue. Designed CNC device serves for easier and more accurate application in production process using standard tubes.</span>

Modelling of Metal Oxide Surge Arresters in Simulation Software DYNAST

This paper describes the possibilities for mathematical modelling of gap-less surge arresters in simulation software DYNAST. This tool does not belong to standard modelling softwares in the field of electric power engineering. However, it may provide some key advantages when compared to more frequently used softwares such as EMTP-ATP and MATLAB-Simulink. Description of the metal oxide varistor modelling at temporary and switching overvoltages, fast-front states, and lightning strokes is presented. More information about the defined internal structure of surge arrester models and ways for implementing respective V-I characteristics are provided. To verify the correct behaviour of the models, both slow and fast overvoltage scenarios are simulated and evaluated.

Efficient Technique for Model Order Reduction Retaining Non-Minimum Phase Characteristics using Clustering Dominant Pole-Zero Algorithm

<span style="font-family: 'Times New Roman',serif; font-size: 10pt; -ms-layout-grid-mode: line; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-GB; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-GB">Model Order Reduction (MOR) challenges a high dimensional problem and plays a key role in areas where dynamic simulation studies are necessary for modern simulation strategy. Many conventional reduction methods namely, reduced order models based on Least Square Method (LSM), Balanced Truncation, Hankel Norm reduction, Dominant Pole Algorithm (DPA) and CDPA method have been developed in the field of control theory. Among these, recently proposed Clustering Dominant Pole Algorithm (CDPA) is able to compute the full set of dominant poles and their cluster center efficiently. In this paper, a hybrid algorithm for model order reduction known as Clustering Dominant Pole-Zero Algorithm (CDPZA) is proposed to identify and preserve the dominant zeros of the processes exhibiting non-minimum phase behaviour. The CDPZA method combines the features of clustering method and DPA. Further, the cluster centers of the dominant zeros in the numerator polynomial are determined using factor division algorithm. The Benchmark HiMAT system of 6^th order is considered for testing and validation of the proposed algorithm. The simulation studies are carried out to show the efficacy of the proposed algorithm over conventional MOR algorithms.</span>

The Digestate: A Nutrient Source for the Alternative Biomass for Anaerobic Digestion

Construction of new biogas plant stations in Europe is a steadily growing trend, that is the reason why there is a need to find a proper alternative source of energy, which can replace traditional crops used for generation of energy. Microalgae represent a high potential of energy. When comparing microalgae with traditional crops, we can point out their high potential (oil content). During the production of biogas from traditional input materials, it is still a great potential of resulting organic waste – fermentation water (digestate), which can be used in a closed cycle in the intensive year-round cultivation of microalgae. Using the by-product (digestate) generated during the process of anaerobic digestion we can create a system for the cultivation of microalgae, which will in turn be used as a raw material for the biogas plant. Thanks to such application, the biogas plant can be more ‘self-sufficient’. This new innovative process can provide a prerequisite scale for increasing commercial use of bioenergy from microalgae. However, there is a need to find a reasonable way to produce the algae biomass to meet all ecological and economic requirements.

Analysis of Transients during the Power System Restoration

The paper presents simulation results of transients during the power system restoration. The Defence plan and Restoration plan development is a part of transmission system operator’s responsibilities and requires thorough calculations, simulations and publication of instructions. The plans focus on extensive failures that have a heavy impact on the system operation and could lead to a blackout. The Restoration plan of power system has to contain procedures for start-up without outside help. TSO regularly checks some part of the Restoration plan.

Summary of the Modern Wheel Slip Controller Principles

<span lang="EN-GB">Railway traction vehicles need to transfer high tractive effort from wheels to rails. The task is complicated because the maximum transferable force continuously changes during the train run, and the change can lead to the high wheels slip velocity or slippage. The effects are undesirable and must be prevented if it is possible or at least limited by slip controllers. There have been several slip controllers developed based on different principles with different degree of complexity and efficiency. The paper summarises principles of the slip control methods and brings their overview with the simulation of their behaviour.</span>