Applied sciences

Bulletin of the Polish Academy of Sciences Technical Sciences

Description

The Bulletin of the Polish Academy of Sciences Technical Sciences is published bimonthly by the Division IV Engineering Sciences of the Polish Academy of Sciences, since the beginning of the existence of the PAS in 1952. The journal is peer‐reviewed and is published both in printed and electronic form. It is established for the publication of original high quality papers from multidisciplinary Engineering sciences with the following topics preferred:

Artificial and Computational Intelligence,
Biomedical Engineering and Biotechnology,
Civil Engineering,
Control, Informatics and Robotics,

Electronics, Telecommunication and Optoelectronics,
Mechanical and Aeronautical Engineering, Thermodynamics,
Material Science and Nanotechnology,
Power Systems and Power Electronics.

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Journal Metrics:

JCR Impact Factor 2023:	1.2
5 Year Impact Factor 2022:	1.1
CiteScore 2023:	2.8
SCImago Journal Rank (SJR) 2023:	0.282
Source Normalized Impact per Paper (SNIP) 2023:	0.573
Ministry of Education and Science:	100 points

Abbreviated title: Bull. Pol. Acad. Sci. Tech. Sci.

ISSN

ISSN 2300-1917

Editorial Board 2023-2025

Editor-in-Chief:

A. Rogalski, Military University of Technology

Honorary (Past) Editor-in Chief:

T. Kaczorek, Warsaw University of Technology

M.P. Kaźmierkowski, Warsaw University of Technology

Deputy Editor-in-Chief:

B. Błachowski, Institute of Fundamental Technological Research PAN

M. Mrozowski, Gdansk University of Technology

Board of Topical Co-editors:

Artificial and Computational Intelligence

S. Osowski, B. Sawicki and T. Leś, Warsaw University of Technology

Biomedical Engineering and Biotechnology

D. Pijanowska, Institute of Biocybernetics and Biomedical Engineering PAN

Civil Engineering

L. Czarnecki, Building Research Institute, ITB, Warsaw

Ł. Sadowski, Wroclaw University of Science and Technology

Control, Robotics and Informatics

J. Klamka and A. Babiarz, Silesian Technical University

J. Stefanowski, Poznan University of Technology

Electronics, Telecommunication and Optoelectronics

M. Mrozowski and A. Lamęcki, Gdansk University of Technology

Mechanical and Aeronautical Engineering, Thermodynamics

B. Błachowski, Institute of Fundamental Technological Research PAN

G. Zboiński, Institute of Fluid-Flow Machinery PAN and University of Warmia and Mazury in Olsztyn

Materials Science and Nanotechnology

B. Major and P. Czaja, Institute of Metallurgy and Materials Science PAN

Power Systems and Power Electronics

J. Rąbkowski and M. Jasiński, Warsaw University of Technology

International Editorial Advisory Board

R. Asthana, University of Wisconsin-Stout, Menomonie, USA

Xu Binshi, China Association of Plant Engineering, Beijing, P.R. China

F. Blaabjerg, Aalborg University, Denmark

C. Cecati, University of L’Aquila, Italy

A. Cichocki, RIKEN Institute, Tokyo, Japan

M. David, National Polytechnique de Toulouse, France

R. Ebner, Materials Centre Leoben, Leoben, Austria

E. Fornasini, University of Padova, Padova, Italy

L.G. Franquelo, University of Sevilla, Spain

M. Gad-el-Hak, Virginia Commonwealth University, Richmond, USA

M. Giersig, Free University of Berlin, Germany

D. van Gemert, Catholic University Leuven, KU Leuven, Belgium

L. Keviczky, Hungarian Academy of Sciences, Budapest, Hungary

V. Kučera, Czech Technical University in Prague, Prague, Czech Republic

R. Kennel, Technical University Munich, Germany

T.A. Kowalewski, Institute of Fundamental Technological Research PAN

E. Levi, Liverpool John Moore University, UK

G. Maier, Technical University of Milan, Milan, Italy

K.F. Man, City University of Hong Kong,

R. Maniewski, Institute of Biocybernetics and Biomedical Engineering PAN

H.A. Mang, Austrian Academy of Sciences, Vienna, Austria

H. Mihashi, Tohoku University, Aoba-ku, Sendai, Japan

S. Mindess, University of British Columbia, Vancouver, Canada

D.A. Mlynski, University of Karlsruhe, Karlsruhe, Germany

A.S. Nowak, University of Michigan, Ann Arbor, USA

K. Ohnishi, Keio University, Yokohama, Japan

A. Öberg, Linköping University, Linköping, Sweden

W. Pedrycz, University of Alberta, Canada

M. Razeghi, Northwestern University, Evanston, USA

J. Rodriguez, University of Andres Bello, Santiago, Chile

J.V. Sloten, Catholic University Leuven, Leuven, Belgium

B.M. Wilamowski, University of Auburn, Alabama, USA

A.L. Yarin, University of Illinois at Chicago, USA

Du Xiangwan, Chinese Academy of Engineering, China

J. Żurada, Department of Computer Engineering, University of Louisville, USA

Editorial Office:

Pałac Kultury i Nauki

Wydział IV Nauk Technicznych PAN

Pl. Defilad 1

PL 00-901 Warszawa

Managing Editor:

Renata Podraza, e-mail: Renata.Podraza@pan.pl

Finance:

Katarzyna Łasak, e-mail: Katarzyna.Lasak@pan.pl

The Bulletin of the Polish Academy of Sciences Technical Sciences is an open access journal with all content available with no charge in full text version.

The journal content is available under the licencse CC BY 4.0 https://creativecommons.org/licenses/by/4.0/.

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Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5

1 Contents vol. 72 no. 5 - Special Section

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5

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2 Contents vol. 72 no. 5 - Regular Papers

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5

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3 New control algorithms, modern devices, and materials in electric energy conversion systems

Jacek Kabziński , Marek Jasiński , Jacek Rąbkowski

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e151676 | DOI: 10.24425/bpasts.2024.151676

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Authors and Affiliations

Jacek Kabziński

e-mail:

ORCID:

Marek Jasiński

e-mail:

ORCID:

Jacek Rąbkowski

e-mail:

ORCID:

Lodz University of Technology, Łódź, Poland
Warsaw University of Technology, Warszawa, Poland

4 Dynamic modeling and identification of a reluctance synchronous machine parameters

Łukasz J. Niewiara , Michał Gierczyński , Tomasz Tarczewski , Lech M. Grzesiak

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e151042 | DOI: 10.24425/bpasts.2024.151042

Keywords: reluctance synchrononus motor electrical circuit modeling parameter identification dynamic modeling

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Abstract

This article discusses an identification and modeling approach of a reluctance synchronous motor (RSM) based on the running rotor technique. The applied flux linkage approximation functions reflect the self-saturation and cross-saturation effects, and the applied mathematical model is continuous and differentiable. The proper design of the experiment is discussed, and relevant recommendations are made to ensure the mitigation of procedural mistakes in the experiments. A detailed analysis of the impact of configuration faults on the obtained experimental data is provided, considering distortions in the obtained flux linkage and inductance surfaces. Considering the achieved model accuracy, a novel model evaluation considering the achieved model accuracy technique based on transient current response is proposed.

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Authors and Affiliations

Łukasz J. Niewiara

e-mail:

ORCID:

Michał Gierczyński

e-mail:

ORCID:

Tomasz Tarczewski

e-mail:

ORCID:

Lech M. Grzesiak

e-mail:

ORCID:

Institute of Engineering and Technology, Nicolaus Copernicus University in Torun, ul. Wilenska 7, 87-100 Torun, Poland
Institute of Control and Industrial Electronics, Warsaw University of Technology, ul. Koszykowa 75, 00-662 Warsaw, Poland

5 Robust control of motion in presence of uncertain parameters and control constraints

Marcin Jastrzębski , Jacek Kabziński , Przemysław Mosiołek

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150335 | DOI: 10.24425/bpasts.2024.150335

Keywords: nonlinear control servo control robust control

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Abstract

The paper describes a novel, simple servo drive position controller, using solely the knowledge about the structure of the nonlinear model and the constraints met by individual components of the model. The desired behavior of the position and velocity signals is obtained by imposing a time-varying constraint on the signal aggregating information about the position and velocity tracking errors. The method allows you to determine the maximum control (servo drive current) necessary to achieve the control goal under the existing initial conditions and the selected reference trajectory. The control is constrained and consists in appropriate reaction when the trajectory approaches the barrier, the shape of which is responsible for the imposed properties of the transient and quasi-steady state tracking error. In addition to the derivation of the control, a discussion of its possible variants and basic properties is presented. Control with time-varying constraints has been introduced, which allows the control objectives to be met with limited conservatism of the imposed constraints. The influence of technical factors related to actual speed and position measurements was discussed and the operation of the real drive on a laboratory stand was presented.

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Authors and Affiliations

Marcin Jastrzębski

e-mail:

ORCID:

Jacek Kabziński

e-mail:

ORCID:

Przemysław Mosiołek

e-mail:

ORCID:

Lodz University of Technology, Institute of Automatic Control, Poland

6 Current sensor fault-tolerant control based on modified Luenberger observers for safety-critical vector-controlled induction motor drives

Michal Adamczyk , Teresa Orłowska-Kowalska

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e151041 | DOI: 10.24425/bpasts.2024.151041

Keywords: induction motor drives fault-tolerant control current sensor faults modified Luenberger observers fault detection fault compensation

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Abstract

Vector-controlled drives require stator current information for use in current feedback and/or state variable estimators. That is why the detection and compensation of possible current sensor (CS) damage is so important. This article focuses on CS fault-tolerant control (FTC) in induction motor (IM) drive systems. In contrast to solutions known from the literature, two modified Luenberger observers (MLO) were applied, allowing for high-quality estimation of currents used in the detector and fault compensator. In a simple implementation of a detection algorithm based on residuals, an adaptive threshold coefficient was employed, enabling effective detection of various types of faults, regardless of whether the second CS was faulty or intact. The presented solution was evaluated during both motor and regenerative operation, with faults occurring in transient states, unlike solutions known in the literature.

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Authors and Affiliations

Michal Adamczyk

e-mail:

ORCID:

Teresa Orłowska-Kowalska

e-mail:

ORCID:

Wroclaw University of Science and Technology, Department of Electrical Machines, Drives and Measurements, Wrocław, Poland

7 Application of continuous wavelet transform and convolutional neural networks in fault diagnosis of PMSM stator windings

Przemysław Pietrzak , Marcin Wolkiewicz

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150202 | DOI: 10.24425/bpasts.2024.150202

Keywords: fault diagnosis interturn short circuits continuous wavelet transform convolutional neural networks permanent magnet synchronous motor

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Abstract

Efficiency, reliability, and durability play a key role in modern drive systems in line with the Industry 4.0 paradigm and the sustainability trend. To ensure this, highly efficient motors and appropriate systems must be deployed to monitor their condition and diagnose faults during the operation. For these reasons, in recent years, research has been increasingly focused on developing new methods for fault diagnosis of permanent magnet synchronous motors (PMSMs). This paper proposes a novel hybrid method for the automatic detection and classification of PMSM stator winding faults based on combining the continuous wavelet transform (CWT) analysis of the negative sequence component of the stator phase currents with a convolutional neural network (CNN). CWT scalogram images are used as the inputs of the CNN-based interturn short circuits fault classifier model. Experimental tests were conducted to verify the effectiveness of the proposed approach under various motor operating conditions and at an incipient stage of fault propagation. In addition, the effects of the input image format, CNN structure, and training process parameters on model accuracy and classification effectiveness were investigated. The results of the experimental tests confirmed the high effectiveness of fault detection (99.4%) and classification (97.5%), as well as other important advantages of the developed method.

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Authors and Affiliations

Przemysław Pietrzak

e-mail:

ORCID:

Marcin Wolkiewicz

e-mail:

ORCID:

Wrocław University of Science and Technology, Department of Electrical Machines, Drives and Measurements,Wybrzeze Wyspia ˙ nskiego 27, 50-370 Wrocław, Poland

8 Theoretical and experimental comparison of gear systems: planetary mechanical transmission and coaxial magnetic gear

Janusz Kołodziej , Rafał Gabor , Marcin Kowol , Marian Łukaniszyn

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150334 | DOI: 10.24425/bpasts.2024.150334

Keywords: planetary gear magnetic gear torque density local force reliability

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Abstract

Gear systems in today’s industry are one of the critical pillars providing power transformation and matching speed and torque to application requirements. Reliability, high efficiency, and low operating costs are desirable due to the prevalence of gearboxes. This paper provides a comparative analysis of selected mechanical and magnetic gears, using a specific example to point out the advantages and disadvantages of contactless power conversion. After determining the essence of the operation of the magnetic gear on the base model, two magnetic gear optimization cases are presented, testifying to the application potential. An analysis of the stress distribution in the area of the teeth of the mechanical gearbox and the most stressed element of the magnetic gear – the modulator, was carried out. The effects of temperature and load on losses were measured and simulated, and ultimately, the efficiency characteristics of the two gears were also compared.

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Authors and Affiliations

Janusz Kołodziej

e-mail:

ORCID:

Rafał Gabor

e-mail:

ORCID:

Marcin Kowol

e-mail:

ORCID:

Marian Łukaniszyn

e-mail:

ORCID:

Faculty of Electrical Engineering, Automatic Control and Informatics, Opole University of Technology, Poland

9 Selected aspects of the operation of dual active bridge DC/DC converters

Serafin Bachman , Marek Turzyński , Marek Jasiński

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150807 | DOI: 10.24425/bpasts.2024.150807

Keywords: DC/DC converters power electronic devices dual active bridge converter DC chargers

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Abstract

This review paper discusses the concept of a bidirectional dual active bridge (DAB) DC/DC converter. Practical applications and control methods are explored, and various types of DAB converters are introduced and characterized. Aspects of operation are discussed, and enriched by the results of theoretical analyses, simulations, and experimental measurements of the original authors’ work.

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Authors and Affiliations

Serafin Bachman

e-mail:

ORCID:

Marek Turzyński

Marek Jasiński

e-mail:

ORCID:

Warsaw University of Technology, Institute of Control and Industrial Electronics, Poland
Gdansk University of Technology, Department of Power Electronics and Electrical Machines, Poland

10 Resonant step-down DC-DC converter based on GaN power integrated circuits and SiC diodes

Robert Stala , Szymon Folmer , Andrzej Mondzik

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150116 | DOI: 10.24425/bpasts.2024.150116

Keywords: Gallium nitride transistor (GaN) GaN power IC silicon carbide diode (SiC diode) DC-DC buckconverter high frequency high efficiency

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Abstract

In the paper results of the operation and efficiency of a DC-DC resonant converter with a switched capacitor topology, equipped with GaN transistors and SiC diodes are presented. Investigated problems are related to the optimization of the DC-DC power electronic converter in order to achieve miniaturization, a simplified design, and high efficiency. The proposed system operates at a high frequency with low switching losses. The proposed design helps to achieve uniform heating of the transistors and diodes, as demonstrated by the results of the thermal imaging measurements. The GaN transistors are integrated into one package with dedicated gate drivers and used to simplify the circuitry of drivers and increase the power density factor of the proposed device. In the high-frequency design presented in the paper, the converter is implemented without electrolytic capacitors. The results included in the paper contain waveforms recorded in the power circuit at ZVS operation when switching on the transistors. It occurs when the system operates above the frequency of current oscillations in the resonant circuit of the switched capacitor. Efficiency characteristics and a voltage gain curve of the converter versus its output power are presented as well. The results of efficiency and quality of waveforms are important because they facilitate characterizing the tested system for implementation using WBG devices. The use of integrated GaN modules to minimize elements in the physical system is also unique to this model and it allows for very short dead-time use, and operation in ZVS mode at low reverse-conduction losses.

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Authors and Affiliations

Robert Stala

e-mail:

ORCID:

Szymon Folmer

e-mail:

ORCID:

Andrzej Mondzik

e-mail:

ORCID:

AGH University of Krakow

11 Quasi Z-source direct matrix converter for enhanced resilience to power grid faults in permanent magnet synchronous motor applications

Przemysław Siwek , Konrad Urbański

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150201 | DOI: 10.24425/bpasts.2024.150201

Keywords: permanent magnet synchronous motor quasi Z-source direct matrix converter voltage sag speed control fault tolerance

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Abstract

In this paper, a voltage control system for a PMSM motor based on the QZSDMC converter is proposed, which allows operation in both buck and boost modes as a possible method to make the drive resistant to power grid voltage sags. The authors presented a method for measuring and transforming the output voltage from QZS, enabling the use of a PI controller to control the voltage supplied to the DMC converter. The publication includes simulation and experimental studies comparing the operation of a PMSM motor powered by DMC and the proposed QZSDMC with voltage control. Simulation studies confirm the drive with QZSDMC resistance to voltage sags up to 80% of the rated value. Experimental studies demonstrate the correct operation of PMSM even with a power grid voltage amplitude equal to 40% of the rated value.

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Authors and Affiliations

Przemysław Siwek

e-mail:

ORCID:

Konrad Urbański

e-mail:

ORCID:

Poznan University of Technology, Institute of Robotics and Machine Intelligence, Piotrowo 3A, 60-965 Poznan, Poland

12 Experimental test results of an automatic voltage regulator with independent phase voltage controllers

Wojciech Śleszyński , Artur Cichowski , Krzysztof Jakub Szwarc , Robert Małkowski , Paweł Szczepankowski , Andrzej Augusiak , Dariusz Karkosiński , Ryszard Strzelecki

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150331 | DOI: 10.24425/bpasts.2024.150331

Keywords: automatic voltage regulator grid voltage control distribution transformer hybrid transformer power electronics converter smart grids

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Abstract

The growing number of distributed renewable energy sources and dynamic constant-power loads (e.g. electric vehicle charging stations) pose new challenges for network operators. These changes result in alterations to network load profiles and load flows, leading to greater voltage volatility. One effective solution to these problems can be the use of automatic voltage regulators (AVRs), which stabilize and symmetrize voltage output, whether at distribution transformers (DTs) or elsewhere in the distribution network. The device developed by the authors consists of two bidirectional power converters and three single-phase transformers connected in series to the low-voltage grid as a stabilizer. The proposed control system provides accurate and fast regulation of the AVR output voltage (within the range of ±10% of the nominal grid voltage), with each phase being independently adjusted, regardless of the type of power load. The article includes test results demonstrating selected functionalities of the developed AVR. The physical model of the device discussed in the article is a research component of the LINTE2 laboratory of the Gdańsk University of Technology.

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Authors and Affiliations

Wojciech Śleszyński

Artur Cichowski

e-mail:

ORCID:

Krzysztof Jakub Szwarc

Robert Małkowski

e-mail:

ORCID:

Paweł Szczepankowski

e-mail:

ORCID:

Andrzej Augusiak

Dariusz Karkosiński

Ryszard Strzelecki

e-mail:

ORCID:

Arex Sp. z .o.o., Hutnicza 3, 81-212 Gdynia, Poland
Faculty of Electrical and Control Engineering, Gdansk University of Technology, ul. G. Narutowicza 11/12, 80-233 Gdansk, Poland

13 Reconfigurable smart metamaterial for energy transfer control in alternating magnetic fields

Adam Steckiewicz , Aneta Stypułkowska

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e149169 | DOI: 10.24425/bpasts.2024.149169

Keywords: metamaterial magnetic field PID controller smart material resonance

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Abstract

The paper presents a metamaterial with reconfigurable effective properties, intended to operate in alternating magnetic fields. The structure of a resonator, based on a series connection of a planar inductor and a lumped capacitor, is expanded using an additional capacitor with a MOSFET transistor. Due to the presence of the controllable active element, it is possible to dynamically change the phase of the current flowing through a meta-cell and shift a frequency response within an assumed range. Since the transistor is driven by the unipolar square wave with a changeable duty cycle and time delay, two closed-loop controllers were utilized to achieve a smart material, able to automatically attain and maintain the imposed resonant frequency. As a result, the complex effective magnetic permeability of the metamaterial can be smoothly changed, during its operation, via an electrical signal, i.e. by adjusting the parameters of a control signal of the active element. The design of the meta-cell, as well as the measuring, data operation and control part, are presented in detail. An illustrative system is examined in terms of achieving the user-defined resonance point of the metamaterial. Transient responses with estimated settling times and steady-state errors and the effective permeability characteristics for the exemplary cases are shown. The meta-cell is also tested experimentally to validate the theoretically determined effective properties.

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Authors and Affiliations

Adam Steckiewicz

e-mail:

ORCID:

Aneta Stypułkowska

Bialystok University of Technology, Faculty of Electrical Engineering, Wiejska 45D Str., 15-351 Białystok, Poland

14 New PCA-based scheme for process fault detection and identification. Application to the Tennessee Eastman process

Mohamed Guerfel , Anissa Ben Aicha , Kamel Belkhiria , Hassani Messaoud

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150812 | DOI: 10.24425/bpasts.2024.150812

Keywords: PCA modeling process fault FDI principal angles structured residuals Tennessee Eastman process

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Abstract

This paper proposes a new principal component analysis (PCA) scheme to perform fault detection and identification (FDI) for systems affected by process faults. In this scheme, a new modeling method which maximizes the model sensitivity to a certain process fault type is proposed. This method uses normal operating or known faulty data to build the PCA model and other faulty data to fix its structure. A new structuration method is proposed to identify the process fault. This method computes the common angles between the residual subspaces of the different modes. It generates a reduced set of detection indices that are sensitive to certain process faults and insensitive to others. The proposed FDI scheme is successfully applied to the Tenessee Eastman process (TEP) supposedly affected by several process faults.

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Authors and Affiliations

Mohamed Guerfel

e-mail:

ORCID:

Anissa Ben Aicha

2 3

e-mail:

ORCID:

Kamel Belkhiria

Hassani Messaoud

Higher Institute of Applied Science and Technology of Sousse (ISSATSo), University of Sousse, Tunisia
LARATSI, National Engineering School of Monastir (ENIM), University of Monastir, Tunisia
LAS2E, National Engineering School of Monastir (ENIM), University of Monastir, Tunisia

15 Robust fault-tolerant control with dynamic event-triggered mechanism based on observer for nonlinear switched systems

Xiaohan Wang , Xingjian Fu

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150805 | DOI: 10.24425/bpasts.2024.150805

Keywords: switched systems adaptive fault observer robust H∞ control fault-tolerant control dynamic event-triggeredmechanism

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Abstract

In this paper, a robust fault-tolerant control with a dynamic event-triggered mechanism based on the observer is proposed for a nonlinear switched system with faults, external disturbances, and uncertainties. A first-order filter is utilized to equate sensor faults to actuator faults, and the augmented system is constructed. An adaptive observer with H_∞performance is designed based on the augmented system. The condition that the state error and fault error of the adaptive observer are uniformly bounded is given. To save communication resources and reduce the transmission of unnecessary information, an improved dynamic event-triggered mechanism is designed by introducing a fixed threshold and defining a sampling error function based on the observed state and the actual state. This mechanism can further expand the triggering time interval and effectively avoid the Zeno behavior. According to the observed state and real-time fault estimation information at the triggering moment, a fault-tolerant controller for the switched system based on the dynamic event-triggered mechanism is proposed, and the conditions for asymptotic stability of the closed-loop system are provided. Finally, the validity of the proposed method is verified by application simulation for the variant aircraft switched system.

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Authors and Affiliations

Xiaohan Wang

Xingjian Fu

e-mail:

ORCID:

School of Automation, Beijing Information Science and Technology University, Beijing, China

16 A high-accuracy Stewart–lift platform based on a programmable logic controller – comparative case studies

Dawid Pawuś , Michał Witek , Łukasz Klar , Krzysztof Bochenek

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | 151045 | DOI: 10.24425/bpasts.2024.151045

Keywords: Stewart–lift platform inverse dynamics method robust control practical verification comparative studies

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Abstract

The study reports the results of a comparative analysis of advanced high-accuracy Stewart-lift platform along with a comparative study of dynamic control. A control system powered by a programmable logic controller (PLC) was used. The properties of the system were described using a dynamic model using the Lagrange method. The real object was verified by performing several tests and comparing them using quality indicators. The results of verification tests conclusively demonstrate the system suitability for applications within industrial automation and robotics systems.

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Authors and Affiliations

Dawid Pawuś

e-mail:

ORCID:

Michał Witek

Łukasz Klar

Krzysztof Bochenek

Faculty of Electrical Engineerig, Automatic Control and Informatics, Opole University of Technology, Prószkowska Street 76, Opole, 45-758,Poland
KBA Automatic Sp. z o.o., Technologiczna Street 2A, Opole, 45–839, Poland

17 Dropping or marking: a review and evaluation of existing fluid-flow approximation models

Monika Nycz , Tomasz Nycz , Tadeusz Czachórski

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150333 | DOI: 10.24425/bpasts.2024.150333

Keywords: fluid-flow approximation transient states TCP/IP models AQM modelling

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Abstract

Fluid-flow approximation is an approach to modelling and evaluating the performance of vast computer networks. Due to varying traffic and performance of transmission protocols reacting to traffic overloads, computer networks are in a permanent transient state. The fluid-flow method main advantage is its ability to analyse these transient states. The article reviews and organises several versions of this approach, indicating a few errors. The main reason for these errors is confusion or lack of distinction between the two versions of the Internet Protocol – when the queue of packets at a node is too long, they may be destroyed or only marked as redundant. The paper compares and evaluates these fluid-flow approximation models with mild and aggressive settings of RED parameters. The authors build a software system with hitherto unprecedented capabilities regarding the size of the networks to be analysed and with innovative way of organising the calculations. The paper shows how large differences imprecise assumptions can introduce in quantitative results.

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Authors and Affiliations

Monika Nycz

e-mail:

ORCID:

Tomasz Nycz

e-mail:

ORCID:

Tadeusz Czachórski

e-mail:

ORCID:

Department of Computer Networks and Systems, Silesian University of Technology, Akademicka 16, 44-100 Gliwice, Poland
Institute of Theoretical and Applied Informatics, Polish Academy of Sciences, Bałtycka 5, 44-100 Gliwice, Poland

18 Novel temperature-effective modeling and state of charge estimation based on sigma-point Kalman filter for lithium titanate oxide battery

Yusuf Muratoğlu , Alkan Alkaya

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150809 | DOI: 10.24425/bpasts.2024.150809

Keywords: temperature-effective modeling state of charge estimation sigma point Kalman filter battery management system energy storage system

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Abstract

Battery modeling and state of charge (SoC) estimation are critical functions in the effective battery management system (BMS) operation. Temperature directly affects the performance and changes the model accuracy of a battery. Most studies have focused on estimating the internal temperature of the battery from the surface temperature of the battery with the help of sensors. However, due to the high number of cells in battery packs, the increase in sensor costs and the number of parameters have been ignored. Therefore, this article presents a new framework for the temperature effect using the electrical circuit model. The terminal voltage of the battery includes the effect under different operating conditions. This effect was associated with internal resistance in the battery model. The developed temperature-effective battery model was tested at different temperatures and operating currents. The model was validated with a maximum average root mean square error of 0.05% from the test results. The SoC of the LTO battery was estimated with the sigma-point Kalman (SPK) filter incorporating the developed model. The maximum average root mean square error in the estimation results is 0.11%. It is suitable for practical applications due to its low cost, simplicity, and reliability.

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Authors and Affiliations

Yusuf Muratoğlu

e-mail:

ORCID:

Alkan Alkaya

e-mail:

ORCID:

Department of Electronics and Automation, Vocational High School, Toros University, Mezitli 33340, Mersin, Turkey
Department of Electrical and Electronics Engineering, Faculty of Engineering, Mersin University, Ciftlikkoy 33100, Mersin, Turkey

19 M^X/G/1/∞ single-server queueing system with random volume customers and multiple vacations

Oleg Tikhonenko , Marcin Ziółkowski

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150813 | DOI: 10.24425/bpasts.2024.150813

Keywords: single-server queueing system queueing systems with random volume customers queueing systems with vacations total volume Laplace–Stieltjes transform

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Abstract

In the present paper, we investigate the model of a single-server queueing system with unlimited queue (of M^X/G/1/∞-type), random volume customers, unlimited memory buffer and multiple vacations. In analyzed system, arriving customers (that form Poisson entrance flow of groups of customers) transport some information measured in bytes so they are assumed to be additionally characterized by some non-negative random volume. Customer service time generally depends on his volume. Information delivered by a customer is written out into dedicated unlimited memory buffer until customer ends his service. In addition, in considered system the mechanism of multiple vacations is implemented which means that server can have some breaks (rests) for a random period of time but breaks begin only in the moments when there is no customer present in the system. The above-mentioned mechanism has obvious influence on customer waiting time and, in consequence, on customers total volume. For the introduced model, we obtain general formula for the steady-state customers total volume distribution in the terms of Laplace–Stieltjes transforms as well as formulae defining its first two moments. Analysis of some interesting, practical special cases of the model and numerical computations are attached as well together with examples of possible applications of the model regarding real telecommunication or computer systems.

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Authors and Affiliations

Oleg Tikhonenko

e-mail:

ORCID:

Marcin Ziółkowski

e-mail:

ORCID:

Faculty of Designing. University of Social Science and Humanities – USWPS, Warsaw, Poland
Institute of Information Technology. Warsaw University of Life Sciences – SGGW, Poland

20 Secure system with security protocol for interactions in healthcare Internet of Things

Sabina Szymoniak

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e151049 | DOI: 10.24425/bpasts.2024.151049

Keywords: security protocols security Internet of Things healthcare

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Abstract

The Internet of Things is a network of connected devices that can communicate and share data over the Internet. These devices often have sensors that collect data for various purposes, such as usage statistics, data processing, or performing specific actions based on the collected data. Also, medical Internet of Things devices are crucial in monitoring critical functions, measuring blood glucose levels, indicating when patients require medicine, and ensuring timely medication delivery. Communication in the Internet of Things is demanding, requiring diverse protocols that address communication security concerns. These protocols must be robust and secure, considering technical factors such as the network objective, energy requirements, and the nature of the communication because they can be exploited. This paper proposes an innovative system with a security protocol that supports and improves communication security in modern Internet of Things networks. The protocol aims to enhance communication safety between interconnected devices for information exchange in medicine or healthcare, ensuring the confidentiality and integrity of sent data and devices. The proposed protocol, tested through formal and automated verification, meets all security goals, including identity verification, anonymity protection, and access revokement. It also protects against man-in-the-middle, modification, replay, and impersonation attacks.

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Authors and Affiliations

Sabina Szymoniak

e-mail:

ORCID:

Department of Computer Science, Cz˛estochowa University of Technology, Poland

21 Static anti-windup compensator based on BMI optimisation for discrete-time systems with directional change in controls avoidance

Dariusz Horla

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e151046 | DOI: 10.24425/bpasts.2024.151046

Keywords: anti-windup compensation bilinear matrix inequalities cut-off constraint no directional change in controls

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Abstract

In the paper, a design method of a static anti-windup compensator for systems with input saturations is proposed. First, an anti-windup controller is presented for system with cut-off saturations, and, secondly, the design problem of the compensator is presented to be a non-convex optimization problem easily solved using bilinear matrix inequalities formulation. This approach guarantees stability of the closed-loop system against saturation nonlinearities and optimizes the robust control performance while the saturation is active.

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Authors and Affiliations

Dariusz Horla

e-mail:

ORCID:

Poznan University of Technology, Faculty of Automation, Robotics and Electrical Engineering, ul. Piotrowo 3a, 60-965 Poznan, POLAND

22 Exponential decay of transient values in positive nonlinear systems

Tadeusz Kaczorek

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e151050 | DOI: 10.24425/bpasts.2024.151050

Keywords: exponential decay transient value fractional order positive nonlinear dynamical feedback system

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Abstract

The exponential decay of transient values in nonlinear continuous-time standard and fractional orders with linear dynamical positive feedback systems and of positive linear parts is investigated. Sufficient conditions for the exponential decay of transient values in this class of positive nonlinear systems are established. Procedures for the computation of gains characterizing the class of nonlinear elements are given and illustrated in simple examples.

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Authors and Affiliations

Tadeusz Kaczorek

e-mail: t.kaczorek@pb.edu.pl

ORCID:

Bialystok University of Technology, Faculty of Electrical Engineering, Wiejska 45D, 15-351 Białystok, Poland

23 Optimized design of truck cab lightweighting based on sensitivity hierarchical comparative analysis method

Yiqun Wang , Di Li , Dongze Wu , Yukuan Li , Tao Wang , Xiaokun Wang , Shaoxun Liu

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e151043 | DOI: 10.24425/bpasts.2024.151043

Keywords: truck cab lightweight sensitivity analysis surrogate model sensitivity hierarchical comparative analysis

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Abstract

The relative sensitivity analysis method is important in the field of vehicle lightweighting. Combined with optimization algorithms, experiment of design (DOE), etc., it can efficiently explore the impact of unit mass of components on performance and search for components with lightweight space. However, this method does not take into account the size level of each component and the order of magnitude differences in sensitivity under different operating conditions. Therefore, this paper proposed a sensitivity hierarchical comparative analysis method, on the basis of which the thicknesses of 10 groups of components were screened out as design variables by considering the lightweighting effect,cab performance, and passive safety. Through the optimal Latin hypercube method, 70 groups of sample points were extracted to carry out the experimental design, the Kriging surrogate model was established and the NSGA-II genetic algorithm was used to obtain the Pareto optimal solution set, and ultimately a weight reduction of 13.13 kg was realized under the premise that the entire performance of the cab improved.

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Authors and Affiliations

Yiqun Wang

e-mail:

ORCID:

Di Li

Dongze Wu

Yukuan Li

Tao Wang

e-mail:

ORCID:

Xiaokun Wang

Shaoxun Liu

Shandong University of Technology, China
Rongcheng Compaks New Energy Automobile Co., Ltd., China

24 Innovative design of experimental blade cascad model for in-depth analysis of stall flutter

Pavel Šnábl , Chandra Shekhar Prasad , Pavel Procházka , Ludek Pešek , Václav Uruba , Vladislav Skála

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150806 | DOI: 10.24425/bpasts.2024.150806

Keywords: blade cascade aeroelasticity stall flutter wind tunnel testing

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Abstract

Stall flutter is a serious threat to the operational integrity in turbomachinery, particularly in the final stage rotors of steam turbines and in compressors. Although computer science has developed rapidly and much of the research can be carried out using numerical tools, the simulation of some phenomena, such as stall flutter, is still very challenging and needs to be supported by experimental data. This paper presents an innovative experimental linear blade cascade design with five prismatic blades with pitch degrees of freedom, designed to be operated in a low subsonic wind tunnel. The geometry of the blade cascade was chosen on the basis of the experimental and numerical tests to allow stall flutter initiation. New suspension, measurement and electromagnetic excitation systems were developed and experimentally tested to allow accurate measurement of aerodynamic damping during controlled flutter tests. The novelty of the experimental blade cascade is the possibility of single pulse excitation of the blades. The cascade can be brought to the edge of stability by adjusting the angle of attack and flow velocity, and then the pulse can be used to induce stall flutter. Measurement of both mechanical and flow characteristics, also demonstrated in this paper, will provide data for in-depth analysis of stall flutter initiation and propagation.

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Authors and Affiliations

Pavel Šnábl

1 2

e-mail:

ORCID:

Chandra Shekhar Prasad

Pavel Procházka

Ludek Pešek

Václav Uruba

1 3

Vladislav Skála

Institute of Thermomechanics of the CAS, Department of Dynamics and Vibrations, Dolejškova 1402/5, Praha, 182 00, Czech Republic
Czech Technical University in Prague, Department of Mechanics and Mechatronics, Technická 1902/4, Praha, 166 07, Czech Republic
University of West Bohemia, Department of Power System Engineering, Plzen, 301 00, Czech Republic

25 The effect of the coating process thermal cycle on mechanical properties of AA6061-T6 used for load-carrying elements of a space instrument: a case study

Tomasz Barciński , Robert Kosturek , Tomasz Kowalski , Maciej Bzowski , Roman Wawrzaszek , Karol Mostowy , Jędrzej Baran , Maciej Daukszo

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150338 | DOI: 10.24425/bpasts.2024.150338

Keywords: mechanical properties aluminum satellite thermal cycle safety factor

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Abstract

Components used for the structure of the GLObal Solar Wind Structure experiment in the NASA Interstellar Mapping and Acceleration Probe space mission, made of AA6061-T6 alloy, are subjected to the coating process, where the temperature affects its mechanical properties. This paper aims to examine the impact of the coating thermal cycle on the mechanical properties of AA6061-T6 alloy, which is the load-carrying material in a spaceborne instrument. As a part of the manufacturing process, the parts made of AA6061-T6 are subjected to a coating process at a temperature of about 220◦C for a time longer than 1 hour. This treatment modifies the mechanical properties of the alloy. To evaluate the consequences of this change for spaceborne components, mechanical testing, and numerical simulation were conducted. It was found that as a result of the coating process, the reduction in AA6061-T6 yield strength is about 16%, which entails a decrease in the margins of safety by 25% at its maximum.

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Authors and Affiliations

Tomasz Barciński

Robert Kosturek

e-mail:

ORCID:

Tomasz Kowalski

Maciej Bzowski

Roman Wawrzaszek

Karol Mostowy

Jędrzej Baran

Maciej Daukszo

Space Research Center, Polish Academy of Sciences (CBK PAN), Warsaw, Poland
Department of Fatigue and Machine Design, Faculty of Mechanical Engineering, Military University of Technology, Warsaw, Poland

26 Failure analysis of fibre metal laminate channel section column under axial compressive pulse loading

Monika Zaczynska

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e151048 | DOI: 10.24425/bpasts.2024.151048

Keywords: fiber metal laminates dynamic buckling failure analysis numerical simulations

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Abstract

The study aims to analyse the dynamic buckling phenomenon and assess the role of the stress tensor components in the failure process of a short fibre metal laminate column under axial compressive dynamic loading. The investigation is focused on a channel-section profile composed of three aluminium layers and two doubled composite plies [Al/0/90/Al/90/0/Al]. The numerical analysis was performed on the finite element model, which was validated by experimental static buckling tests. Employing a progressive failure algorithm, this analysis incorporated the material property degradation method and Hashin’s criterion as the damage initiation criterion. Failure initiation in metal layers was based on the Huber-Mises-Hencky failure criterion. Based on the conducted analyses, it was concluded that the dominant forms of destruction in the FML structure are yielding in the metal layers due to excessive compressive stresses and the failure of the matrix in composite plies as a result of compressive and shear stresses. Through a thorough examination of the stress tensor components, critical stresses contributing to aluminium plastic deformation and laminate failure mechanisms were identified.

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Authors and Affiliations

Monika Zaczynska

e-mail:

ORCID:

Department of Strength of Materials, Lodz University of Technology, Stefanowskiego 1/15, 90-537 Lodz, Poland

27 Fault type and fault location detection in transmission lines with 6-convolutional layered CNN

Bilal Gümüs , Heybet Kılıç , Cem Haydaroglu , Ulvi Yusuf Butakın

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e151047 | DOI: 10.24425/bpasts.2024.151047

Keywords: PSCAD CNN style 6-convolutional Layered CNN fault detection

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Abstract

In this article, we propose a data-driven method for short-circuit fault detection in transmission lines that exploits the capabilities of convolutional neural networks (CNNs). CNNs, a class of deep feedforward neural networks, can autonomously detect different features from data, eliminating the need for manual intervention. To mitigate the effects of noise and increase network robustness, we present a CNN architecture with six convolutional layers. The study uses a single busbar power system model developed with the PSCAD simulation program to evaluate the performance of the proposed method. The proposed CNN method is also compared with machine learning methods such as LSTM, SVM and ELM. Our results show a high success rate of 98.4% across all fault impedances, confirming the effectiveness of the proposed CNN methods in accurately detecting short-circuit faults based on current and voltage measurements.

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Authors and Affiliations

Bilal Gümüs

e-mail:

ORCID:

Heybet Kılıç

e-mail:

ORCID:

Cem Haydaroglu

e-mail:

ORCID:

Ulvi Yusuf Butakın

e-mail:

ORCID:

Electrical and Electronics Engineering Department, Faculty of Engineering, Dicle University, Diyarbakır 21280, Turkey
Electric Power and Energy Department, Dicle University, Diyarbakır 21280, Turkey
SCADA System and DMS Manager, Dicle Electricity Distribution Inc., Diyarbakır, Turkey

28 Leveraging active learning techniques for surgical instrument recognition and localization

Bartłomiej Piotrowski , Jakub Oszczak , Krzysztof Sawicki , Barbara Siemiątkowska , Andrea Curatolo

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150337 | DOI: 10.24425/bpasts.2024.150337

Keywords: surgical tool detection eye surgery neural networks data annotation

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Abstract

The field of ophthalmic surgery demands accurate identification of specialized surgical instruments. Manual recognition can be time-consuming and prone to errors. In recent years neural networks have emerged as promising techniques for automating the classification process. However, the deployment of these advanced algorithms requires the collection of large amounts of data and a painstaking process of tagging selected elements. This paper presents a novel investigation into the application of neural networks for the detection and classification of surgical instruments in ophthalmic surgery. The main focus of the research is the application of active learning techniques, in which the model is trained by selecting the most informative instances to expand the training set. Various active learning methods are compared, with a focus on their effectiveness in reducing the need for significant data annotation – a major concern in the field of surgery. The use of convolutional neural networks (CNNs) and recurrent neural networks (RNNs) to achieve high performance in the task of surgical tool detection is outlined. The combination of artificial intelligence (AI), machine learning, and Active Learning approaches, specifically in the field of ophthalmic surgery, opens new perspectives for improved diagnosis and surgical planning, ultimately leading to an improvement in patient safety and treatment outcomes.

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Authors and Affiliations

Bartłomiej Piotrowski

e-mail:

ORCID:

Jakub Oszczak

Krzysztof Sawicki

Barbara Siemiątkowska

e-mail:

ORCID:

Andrea Curatolo

2 3

e-mail:

ORCID:

Institute of Automatic Control and Robotics, Warsaw University of Technology, A. Boboli 8, 02-525 Warsaw, Poland
International Centre for Translational Eye Research, Skierniewicka 10A, 01-230 Warsaw, Poland
Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland

29 HTTNet: hybrid transformer-based approaches for trajectory prediction

Xianlei Ge , Xiaobo Sen , Xuanxin Zhou , Xiaoyan Li

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150811 | DOI: 10.24425/bpasts.2024.150811

Keywords: trajectory prediction transformer convolutional neural network multimodal data

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Abstract

Forecasting future trajectories of intelligent agents presents a formidable challenge, necessitating the analysis of intricate scenarios and uncertainties arising from agent interactions. Consequently, it is judicious to contemplate the establishment of inter-agent relationships and the assimilation of contextual semantic information. In this manuscript, we introduce HTTNet, a comprehensive framework that spans three dimensions of information modeling: (1) the temporal dimension, where HTTNet employs a time encoder to articulate time sequences, comprehending the influences of past and future trajectories; (2) the social dimension, where the trajectory encoder facilitates the input of trajectories from multiple agents, thereby streamlining the modeling of interaction information among intelligent agents; (3) the contextual dimension, where the TF-map encoder integrates semantic scene input, amplifying HTTNet cognitive grasp of scene information. Furthermore, HTTNet integrates a hybrid modeling paradigm featuring CNN and transformer, transmuting map scenes into feature information for the transformer. Qualitative and quantitative analyses on the nuScenes and interaction datasets highlight the exceptional performance of HTTNet, achieving 1.03 minADE10 and a 0.31 miss rate on nuScenes, underscoring its effectiveness in multi-agent trajectory prediction in complex scenarios.

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Authors and Affiliations

Xianlei Ge

1 2

e-mail:

ORCID:

Xiaobo Sen

1 3

Xuanxin Zhou

e-mail:

ORCID:

Xiaoyan Li

4 2

e-mail:

ORCID:

School of Electronic Engineering, Huainan Normal University, China
College of Computing and Information Technologies, National University, Philippines
College of Industrial Education, Technological University of the Philippines, Philippines
School of Computer, Huainan Normal University, China

30 Investigating the effect of electrospark alloying parameters on structure formation of modified nitrogen coatings

Oksana Haponova , Viacheslav Tarelnyk , Tomasz Mościcki , Nataliia Tarelnyk

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150802 | DOI: 10.24425/bpasts.2024.150802

Keywords: electrospark alloying discharge energy productivity coating structure

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Abstract

The quality parameters of surface layers synthesised using electrospark alloying (ESA) technology were analysed in this paper. The main focus was on the influence of equipment energy parameters on structure formation, specifically the effect of discharge energy and productivity. Microstructural analysis of the modified surface of C40 steel after nitriding by ESA using a paste containing nitrogen compounds injected into the interelectrode gap was conducted. The layer structure for all studied ESA parameters includes three areas: the upper “white layer”, the diffusion zone below it, and the substrate. The roughness of the surface is Ra ∼ 0.9 µm at low discharge energy Wp = 0.13 J and Ra ∼ 6 µm at Wp = 3.4 J. The microhardness, continuity, and surface roughness of the layers varied with Wp. The influence of ESA productivity on the structure was studied. The thickness of the hardened layer and the diffusion zone, as well as the microhardness and continuity, are affected by reduced productivity. For the same discharge energy, the thickness of the hardened layer increases by 10-18% with a decrease in productivity compared to the classical mode. Studies have shown that productivity loss has a positive effect on the quality characteristics of the coatings produced by the ESA process.

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Authors and Affiliations

Oksana Haponova

1 2

e-mail:

ORCID:

Viacheslav Tarelnyk

e-mail:

ORCID:

Tomasz Mościcki

e-mail:

ORCID:

Nataliia Tarelnyk

e-mail:

ORCID:

Department of Experimental Mechanics, Institute of Fundamental Technological Research Polish Academy of Sciences,Pawinskiego 5B, 02-106 Warsaw, Poland
Applied Material Science and Technology of Constructional Materials Department, Sumy State University, Kharkivska 116, 40007 Sumy, Ukraine
Technical Service Department, Sumy National Agrarian University, H. Kondratiieva 160, 40021 Sumy, Ukraine

31 The ITO thin films deposited by magnetron sputtering for solar cell applications

Marek Szindler , Magdalena M. Szindler , Krzysztof Lukaszkowicz , Krzysztof Matus , Natalia Nosidlak , Janusz Jaglarz , Mateusz Fijalkowski , Paweł Nuckowski

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150803 | DOI: 10.24425/bpasts.2024.150803

Keywords: surface engineering magnetron sputtering photovoltaics silicon solar cells ITO

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Abstract

The paper presents the results of research on the surface topography and electrical properties of ITO thin films deposited by PVD for applications in silicon photovoltaic cells. The surface condition and chemical composition were characterized using a scanning electron microscope and the thickness and optical constants were measured using a spectroscopic ellipsometer. To compare the impact of the preparation process on the properties of layers, deposition was carried out at three different temperatures: 25, 200, and 400◦C. As the temperature increased, the surface roughness changed, which correlated with the results of structural tests. The crystallite size increased from 11 to 46 nm. This, in turn, reduced the surface resistance. The electrical properties were measured using a four-point probe method and then the prepared solar cells containing ITO thin films in their structure were examined. By controlling the deposition parameters, the surface resistance of the deposited layer (26 Ohm/✷) and the efficiency of the prepared solar cells (18.91%) were optimized. Currently, ITO has the best properties for use in optoelectronics and photovoltaics among the known TCO layers. The magnetron sputtering method is widely used in many industries. Therefore, the authors predict that TCO layers can replace currently used antireflection layers and reduce the number and dimensions of front metal contacts in solar cells.

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Authors and Affiliations

Marek Szindler

e-mail:

ORCID:

Magdalena M. Szindler

e-mail:

ORCID:

Krzysztof Lukaszkowicz

e-mail:

ORCID:

Krzysztof Matus

e-mail:

ORCID:

Natalia Nosidlak

Janusz Jaglarz

Mateusz Fijalkowski

Paweł Nuckowski

Scientific and Didactic Laboratory of Nanotechnology and Material Technologies, Faculty of Mechanical Engineering,Silesian University of Technology, ul. Towarowa 7, 44-100 Gliwice, Poland
Department of Engineering Materials and Biomaterials, Silesian University of Technology, ul. Konarskiego 18a, 44-100 Gliwice, Poland
Materials Research Laboratory, Silesian University of Technology, ul. Konarskiego 18a, 44-100 Gliwice, Poland
Department of Physics, Cracow University of Technology, ul. Podchor ˛azych 1, 30-084 Krakow, Poland
Institute of Materials Engineering, Cracow University of Technology, al. Jana Pawła II 37, 31-864 Krakow, Poland
Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec,Studentská 1402/2, 461 17 Liberec, Czech Republic

32 Performance evaluation of 5G New Radio low-density parity check codes over different scenarios of lognormal fading channel

Mohammed Hussein Ali , Ghanim A. Al-Rubaye

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150808 | DOI: 10.24425/bpasts.2024.150808

Keywords: QAM OFDM NR-LDPC lognormal fading channel BER 5G NR physical uplink shared channel (PUSCH) physical downlink control channel (PDCCH) enhanced mobile broadband (eMBB) LTE-advanced (LTE-A)

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Abstract

Low-density parity check (LDPC) is a channel coding technique widely utilized in the 5G New Radio standard, it is of utmost importance in facilitating proficient and secure communication in noisy environments by effectively minimizing errors during data transmission. It is primarily used in the 5G New Radio (NR) standard for encoding user information on the physical downlink shared channel (PDSCH). The necessity to satisfy the increasing expectations for throughput, latency, and dependability led to the decision to deploy LDPC codes for user data, especially in the enhanced mobile broadband (eMBB) and ultra-reliable and low-latency communications (URLLC) scenarios of 5G networks. The present system proposes the use of NR-LDPC codes to transmit data across a lognormal multipath fading channel model in the presence of AWGN. Wireless communication channels often use a lognormal multipath fading channel model, where the received signal experiences both multipath fading and lognormal shadowing. The research investigates the effectiveness of NR-LDPC coding in improving QAM-OFDM system performance by analyzing two rate-compatible base graphs and comparing their effectiveness with an uncoded system. This analysis is crucial for optimizing communication network design, especially in scenarios where the integrity of data is of utmost importance. We introduce a new method to improve the 5G NR LDPC code capability under lognormal fading conditions. This approach develops a layered min-sum (LMS) algorithm to provide enhanced error-correcting capabilities. The developed and implemented decoding algorithm represents a significant advancement over traditional detection methods. The outcomes of the simulation provide evidence of the effectiveness of the proposed NR-LDPC coding techniques in terms of their error correction and identification capabilities. In addition, the developed LMS decoding algorithm was shown to significantly decrease the BER of the system.

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Authors and Affiliations

Mohammed Hussein Ali

e-mail:

ORCID:

Ghanim A. Al-Rubaye

e-mail:

ORCID:

Electrical Engineering Department, College of Engineering, Mustansiriyah University, Baghdad, Iraq

33 Experimental evaluation of low-voltage DC/DC boost converters for renewable energy applications

Jakub Dawidziuk , Michał Harasimczuk , Rafał Kopacz

Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 5 | e150810 | DOI: 10.24425/bpasts.2024.150810

Keywords: renewable energy boost DC/DC converters high-efficiency converters current-fed converters

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Abstract

The demand for energy in the world is growing, and the requirements for the efficiency of energy-saving technologies used in renewable energy sources, especially prominent in terms of power electronics, are also increasing. In many renewable energy applications, high-efficiency, high-power DC/DC converters are necessary as an interface between various low-voltage sources and higher output voltage loads, e.g. in photovoltaics. The article presents a comprehensive study on reducing power losses in electric energy conversion in modified isolated and non-isolated DC/DC boost converters powered by low-voltage energy sources. The main desirable features, such as high energy efficiency, high conversion ratio, and low stress on the switches and diodes, were compared and further experimentally validated. The experimental evaluation indicates that the highest efficiency of 96.7%, with a conversion ratio of more than 10, was achieved in the interleaved boost-flyback DC/DC converter. Other investigated systems, namely non-isolated push-pull-boost converters, isolated half-bridge boost, and partially parallel boost converters, achieved slightly lower efficiency. Simultaneously, using the suggested topology, the passive component count was reduced. Furthermore, better utilization of switches and a higher conversion ratio are provided, as well as a possibility of working at a lower duty cycle compared to other step-up converter topologies. All in all, the proposed and studied converters exhibit certain advantages over other state-of-theart solutions and thus can be competitively and effectively employed in modern low-voltage DC/DC applications such as photovoltaics.

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Authors and Affiliations

Jakub Dawidziuk

e-mail:

ORCID:

Michał Harasimczuk

e-mail:

ORCID:

Rafał Kopacz

e-mail:

ORCID:

Faculty of Electrical Engineering, Bialystok University of Technology, Białystok, Poland
Institute of Control and Industrial Electronics, Warsaw University of Technology, Warszawa, Poland