Transport And Communications, 2023 (vol. 11), issue 1
Experimental Measurements of Four Parallel-Connected Three-Phase Inverters of Railway Auxiliary Converters
Zdeno Biel, Marek Franko
Transport And Communications 2023, 11(1):1-4 | DOI: 10.26552/tac.C.2023.1.1 
In this paper, experimental measurements of four parallel-connected three-phase inverters of railway auxiliary converters were carried out. The purpose of this measurement was to verify the ability of parallel co-operation of four three- phase inverters connected to a common three-phase bus, verifying the starting sequence of the inverters and power sharing by individual converters. The converters were powered by a common high voltage AC source and the outputs were intercon- nected to form a common three-phase network. The ability to uniform power sharing was tested during 15 kW and 137 kW motor acceleration. The results showed that all inverters...
High power – high frequency transformer design constrains
Marek Franko, Roman Kučera, Zdeno Biel, Roman Holček
Transport And Communications 2023, 11(1):5-9 | DOI: 10.26552/tac.C.2023.1.2
This paper describes the design of a middle-frequency power transformer, its material composition and the design of the magnetic circuit and windings, operating in the frequency range 800 to 2000Hz, with a capacity of 200kVA, air-cooled, to be fed from a suitable frequency converter, characterized by reduced noise. The proposed solution allows the implementation of galvanically isolated DC-DC converters for auxiliary traction drives and other DC-DC converters.
Input impedance of static power inverter of auxiliary drives of rolling stock according to UIC 550-3
Marek Franko, Roman Kučera, Zdeno Biel, Roman Holček
Transport And Communications 2023, 11(1):10-14 | DOI: 10.26552/tac.C.2023.1.3
This paper focuses on the topic of the input impedance of static power inverters, which is a crucial parameter for controlling and regulating power inverters in rolling stock. The standard UIC 550-3 specifies the requirements for the input impedance of static power inverters used as auxiliary drives on rolling stock.
Measurement of the influence of changes in the HV converter SW on the input impedance
Marek Franko, Roman Kučera, Zdeno Biel, Roman Holček
Transport And Communications 2023, 11(1):15-17 | DOI: 10.26552/tac.C.2023.1.4
This paper, we focus on the measurement of the effect of the SW filter division frequency shift of the measured input voltage on the value of the input impedance at an input signal frequency of 50 Hz. The aim of the measurement is to find out what effect this shift has on the input impedance and thus on the performance and efficiency of the whole system.
Measurement Of Parallel Operation Of Inverters To Common 3 Phase Network
Peter Jeck, Zdeno Biel
Transport And Communications 2023, 11(1):18-22 | DOI: 10.26552/tac.C.2023.1.5
In the article, we describe the measurement of parallel cooperation of inverters connected to a common three- phase network on train carriage with real loads. In the beginning, we will describe the used equipment and then we will describe the individual measurement procedures and their results. We will show the results of the measurements, when loading two inverters with two train carriage, four and eight carriage. Finally, the results of measurements with 6 inverters power on and a load of up to 14 train carriages.
Modelling the Influence of Service Quality of Travel Mode on Tourism Satisfaction in Lagos State, Nigeria. A Tourist-Based Perception Study
Umar Obafemi Salisu, Samuel G. Odewumi, Forson Ibraheem Abdul-Azeez
Transport And Communications 2023, 11(1):23-37 | DOI: 10.26552/tac.C.2023.1.6
Tourism has remained a vital component of the economies of many major destination nations around the world due to its attributed benefits and opportunities, including economic diversification, improved quality of life, revenue generation, job creation, and sustainability of the ecosystem. Tourism can only achieve all these benefits with adequate provisioning and viable operations, maintenance, and management of transport systems. Unfortunately, the provision and operations of the transport system, especially travel modes for tourism activities in Lagos State, are faced with various challenges and externalities that consequently affect tourists’...
Data acquisition unit for road vehicle or aircraft
Vojtech Šimák, Matúš Danko
Transport And Communications 2023, 11(1):38-40 | DOI: 10.26552/tac.C.2023.1.7
Data acquisition is a critical aspect of modern vehicle and aircraft design, as it provides engineers and researchers with essential information on the performance and behaviour of these vehicles in various operating conditions. In this paper, we present a data acquisition unit (DAU) for road vehicle or aircraft that utilizes various sensors, including GNSS, INS, RPM measurement, barometric altimeter, and ESP32 microcontroller. The DAU consists of multiple sensors, including a GNSS receiver to determine the vehicle's position, speed, and heading. An inertial navigation system (INS) is used to measure the vehicle's acceleration and angular rate. RPM...
GNSS Spoofing – Advanced Mechanizms of Detection
Vojtech Šimák, Jozef Šedo
Transport And Communications 2023, 11(1):41-44 | DOI: 10.26552/tac.C.2023.1.8
GNSS spoofing is a technique used to deceive Global Navigation Satellite Systems (GNSS) receivers by broadcasting fake signals that appear to be genuine. To detect GNSS spoofing, a receiver can use various techniques such as monitoring signal strength, cross-checking data from multiple satellites, comparing the signal characteristics with the expected patterns, and analyzing the timing and location information. Advanced detection methods may use machine learning algorithms to identify anomalies and patterns in the signal data. In addition, the use of encrypted signals and multiple frequency bands can make spoofing more difficult, and the implementation...