Tamás Orosz

Széchenyi István University

Due to the rise of e-mobility applications, there is an increased demand to create more accurate control methods, which can reduce the loss in an e-drive system. The accurate modeling of the rotating machines needs to resolve a partial differential equation system that describes the thermal and mechanical behavior of the different parts in addition...

Induction heating is a clear, cheap, and highly effective technology used for many industrial and commercial applications. Generally, a time-varying magnetic field produces the required heat in the workpiece with a specially designed coil. The efficiency of the heating process depends highly on the coil design and the geometrical arrangement. A det...

Additive manufacturing of soft magnetic materials is a promising technology for creating topologically optimized electrical machines. High-performance electrical machines can be made from high-silicon-content FeSi alloys. Fe-6.5wt%Si material has exceptional magnetic properties; however, manufacturing this steel with the classical cold rolling meth...

Innovative technological solutions have become increasingly critical in addressing the transportation sector’s environmental impact. Passenger vehicles present an opportunity to introduce novel drivetrain solutions that can quickly penetrate the electric vehicle market due to their shorter development time and lifetime compared to commercial vehicl...

The installed solar capacity in the European Union has expanded rapidly in recent years. The production of these plants is stochastic and highly dependent on the weather. However, many factors should be considered together to estimate the expected output according to the weather forecast so that these new PV plants can operate at maximum capacity....

The European Union’s increasing focus on sustainable and eco-friendly product design has resulted in significant pressure on original equipment manufacturers to adopt more environmentally conscious practices. As a result, the remanufacturing of end-of-life electric machines is expected to become a promising industrial segment. Identifying the missi...

Three-dimensional printing is a promising technology that offers increased freedom to create topologically optimised electrical machine designs with a much smaller layer thickness achievable with the current, laminated steel-sheet-based technology. These composite materials have promising magnetic behaviour, which can be competitive with the curren...

The accurate measurement and modeling of ferromagnetic material losses are vital issues during the design and analysis of electrical machines. Higher loss values can describe the manufactured rotor and stator machine plates better than the catalog data obtained by standardized measurements using the Epstein frame. In this paper, different temperatu...

This paper presents a novel form of feedback linearization control (FBL) of boost-type DC/DC converter: to reach highly accurate output voltage control. Integral action has been inserted into the block diagram of the control scheme. The state-space model of the boost converter is highly nonlinear. Accordingly, the design procedure of the controller...

Optimization is an essential part of designing electrical machines and devices. Considering the uncertainties and tolerances from the beginning of the design process can lead to a more robust design and significantly reduce the number of waste products during the manufacturing process. However, the computational demand for these robust design optim...

With the recent advancements of the fourth industrial revolution, many sensors are implemented into the products that collect the data and monitor their performance. The measurement data can be stored with the numerical models as a digital twin, and these can serve as a virtual replica of a physical object or process. These digital twins can improv...

There were many promising superconducting materials discovered in the last decades that can significantly increase the efficiency of large power transformers. However, these large machines are generally custom-made and tailored to the given application. During the design process the most economical design should be selected from thousands of applic...

This article introduces a Special Issue (SI) that contains fourteen chosen articles from robust design optimization of electrical machines and devices [...]

There is a great potential in small satellite technology for testing new sensors, processes, and technologies for space applications. Antennas need careful design when developing a small satellite to establish stable communication between the ground station and the satellite. This work is motivated by the design of an antenna array for a future rot...

One of the most time-consuming parts of an attorney’s job is finding similar legal cases. Categorization of legal documents by their subject matter can significantly increase the discoverability of digitalized court decisions. This is a multi-label classification problem, where each relatively long text can fit into more than one legal category. Th...

Many machine learning-based document processing applications have been published in recent years. Applying these methodologies can reduce the cost of labor-intensive tasks and induce changes in the company’s structure. The artificial intelligence-based application can replace the application of trainees and free up the time of experts, which can in...

Tolerance analysis is crucial in every manufacturing process, such as electrical machine design, because tight tolerances lead to high manufacturing costs. A FEM-based solution of the tolerance analysis of an electrical machine can easily lead to a computationally expensive problem. Many papers have proposed the design of experiments, surrogate-mod...

The optimization of the design of a practical electromagnetic device involves many challenging tasks for new algorithms, especially those involving numerical modeling codes in which objective function calls must be minimized for practical design processes. The Compumag Society provides openly accessible, challenging benchmark problems (TEAM problem...

Data sharing is a central aspect of judicial systems. The openly accessible documents can make the judiciary system more transparent. On the other hand, the published legal documents can contain much sensitive information about the involved persons or companies. For this reason, the anonymization of these documents is obligatory to prevent privacy...

Sorting out the legal documents by their subject matter is an essential and time-consuming task due to the large amount of data. Many machine learning-based text categorization methods exist, which can resolve this problem. However, these algorithms can not perform well if they do not have enough training data for every category. Text augmentation...

Optimization of axial flux permanent-magnet motors is a very important topic in the literature and requires high performance optimization algorithms and finite element analysis. This paper gives a summary of the analysis methods of axial flux permanent-magnet motors currently available in the literature. An open-circuit model was built and describe...

This paper presents the design and a design analysis of a coaxial, linear transformer. This is a novel high frequency transformer concept for energy conversion. The examined transformer was designed for 1 MHz nominal frequency. One of the main advantages of the proposed transformer design is its simple winding system. It contains only two coaxial c...

Reference implementation of Digital Twins for electrical energy conversion systems is an important and open question in the industrial domain. Digital Twins can predict the future performance, behaviour, and maintenance needs of a complex system. Today the concept of Digital Twins is not only an emulation or simulation of the physical object along...

Benchmarking is essential for testing new numerical analysis codes. Their solution is crucial both for testing the partial differential equation solvers and both for the optimization methods. Especially, nature-inspired optimization algorithm-based solvers, where is an important study is to use benchmark functions to test how the new algorithm may...

Cost optimization of power transformers is a complex engineering task. The design engineers have to solve this multidisciplinary, non-linear optimization problem in a very short-time. Due to the importance of the topic, numerous optimization methods have been developed in the industry to solve this problem. These methods generally use different, si...

The bio-inspired algorithms are novel, modern, and efficient tools for the design of electrical machines. However, from the mathematical point of view, these problems belong to the most general branch of non-linear optimization problems, where these tools cannot guarantee that a global minimum is found. The numerical cost and the accuracy of these...

Benchmarking is essential for testing new numerical analysis codes. Their solution is crucial both for testing the partial differential equation solvers and both for the optimization methods. Especially, nature-inspired optimization algorithm-based solvers, where is an important study is to use benchmark functions to test how the new algorithm may...

Two powerful and versatile code packages (Agros Suite and Ārtap) are presented for design and optimization of technical devices and systems. Agros Suite represents an environment for numerical solution of systems consisting of partial differential equations (PDEs) of the second order by a higher-order finite element method with a lot of further adv...

Since the electrical machine design is a complex task it can be divided into sub-problems, e.g. preliminary and final design processes and checking of the final design. This paper deals with the preliminary design process, which provides the key-design parameters of the electrical machine. Traditionally, these electrical machine models in prelimina...

Since large power transformers are custom-made, and their design process is a labor-intensive task, their design process is split into different parts. In tendering, the price calculation is based on the preliminary design of the transformer. Due to the complexity of this task, it belongs to the most general branch of discrete, non-linear mathemati...

Nowadays, there is a huge interest in the design of medium frequency transformers. Due to their high power density and relatively good efficiency. These transformers are still used in wind farms and traction, where not only the efficiency, but the overall size and weight of the transformer are important design criteria. However, the determination o...

Purpose The purpose of this paper is to compare different reduced-order models for models of control of induction brazing process. In the presented application, the problem is to reconstruct temperature at the points of interests (hot spots) from information measured at accessible places. Design/methodology/approach The paper describes the process...

Since large power transformers are custom-made, and their design process is a labor-intensive task, their design process is split into different parts. In tendering, the price calculation is based on the preliminary design of the transformer. Due to the complexity of this task, it belongs to the most general branch of discrete, non-linear mathemati...

The main goal of the Artap project is to provide an extensive infrastructure for robust design optimization, where usually many different numerical solvers have to be used together and the impact of the manufacturing uncertainties have to be minimized. Artap is an open-source software platform, developed jointly with the coupled numerical field sol...

The main goal of the Artap project is to provide an extensive infrastructure for robust design optimization, where usually many different numerical solvers have to be used together and the impact of the manufacturing uncertainties have to be minimized. Artap is an open-source software platform, developed jointly with the coupled numerical field sol...

Design of electrical machines with low carbon footprint is an actual topic in the industry. Total cost of ownership is the standardized methodology to consider the lifetime costs of a power transformer already in the pre-concept design stage. There still does not exist a widely accepted method to calculate the carbon footprint of power transformers...

Design of electrical machines with low carbon footprint is an actual topic in the industry. Total cost of ownership is the standardized methodology to consider the lifetime costs of a power transformer already in the pre-concept design stage. There still does not exist a widely accepted method to calculate the carbon footprint of power transformers...

Accurate temperature control is an important part of an induction brazing process, because of a small difference between melting points of aluminum and soldering material. However, direct measurement of the local temperature at the spot of brazing is not possible in a production line. This temperature can be calculated from the results of indirect...

Transformer design is a challenging engineering task, where the different physical fields have to be harmonized together to fulfill the implied specifications. Due to the difficulty of this task, it can be separated into several subproblems. The first subproblem, in the pre-concept phase, during the transformer design is the calculation of the cost...

Making a competitive transformer design is a nonlinear mathematical optimization task which should be solved in the tendering design stage. Due to the complexity of the power transformer design, a wide range of optimization algorithms are been proposed in the literature. Despite the large number of design optimization methods, most of them neglect...

The focus of my thesis is the electrical machine design cost optimization problems, which related to the preliminary design stage. This optimization task belongs to the most general branch of the non-linear mathematical optimization problems. Numerous mechanical, thermal and electrical constraints should be considered simultaneously to determine th...

The first step in transformer design optimization is to solve a non-linear optimization task. Here, not only the physical and technological requirements, but the economic aspects are also considered. Large number of optimization algorithms have been developed to solve this task. These methods result the optimal electrical parameters and the shape o...

Large power transformers are regarded as crucial and expensive assets in power systems. Due to the competing global market, to make a good and competing power transformer design, a non-linear optimization problem should be solved in a very short time in the preliminary design stage. The paper shows and compares the performance of four different met...

The first step in the transformer design process is to find the active part’s key design parameters. This is a non-linear mathematical optimisation task, which becomes more complex if the economic conditions are considered by the capitalisation of the losses. Geometric programming combined with the method of branch and bound can be an effective and...

The temperature rise calculation of core-type power transformers is an essential question in the design process however this is neglected during the preliminary optimization process. The methods of the calcula- tion methods are classified and introduced shortly and they applicability is examined for the preliminary design process. For comparison of...

The behavior of coils in case of fast transient pulses is different from that they show at low frequencies. If the dimensions of the coil, i.e. mainly the length of the winding is much shorter than the wavelength of the signal on the coil, a lumped element model can be effectively used taking the capacitances of windings into consideration. In this...

The main intent of the power transformer design optimization in the tendering stage is to find those mechanical and electrical parameters, which minimize the machines' total cost of the ownership by reducing the different power losses and the manufacturing costs. To find the optimal transformer design parameters and make them harmonize with the eco...

Because of the strong competition in the equipment market, the aim of the manufacturers is to reduce the product price as much as possible, fulfill the high-quality standards, and improve the reliability and efficiency of the transformers. The capitalization of the costs enables to handle the different economic and technological parameters together...

The optimization of power transformers is one of the earliest applications of geometric programming. This approach works well with shell-form transformers, and the constructed models can be solved accurately with the new interior point method based solvers. However, a less well-known fact is that this kind of modeling becomes problematic in the cas...

In today's competitive markets there is an ever pressing need for the transformer manufacturing industry to improve transformer efficiency and to cut down costs by reducing no-load and load losses with improved design. On the other hand, total cost of the production of the transformer, its installation and maintenance should also be minimized. The...

The Rogowski current transducers are widely used because they have several advantages over iron-cored devices: no saturation at high current, higher operating frequency and less error in wider measurement range. The main components of these current transducers are the measuring coil and integrator. Latter can be passive or active. The main advantag...

A good transformer design satisfies certain functions and requirements. We can satisfy these requirements by various designs. The aim of the manufacturers is to find the most economic choice within the limitations imposed by the constraint functions, which are the combination of the design parameters resulting in the lowest cost unit. One of the ea...

Tartalmi kivonat: A Geometriai Programozás (GP) formalizmusával felírt nemlineáris optimalizálási feladatok egyik első alkalmazása a nagytranszformátorok költségoptimalizálása volt. Fő előnye a GP alkalmazásának a gyakorlati tervezés szempontjából, hogy az ebben a formalizmusban felírt optimalizálási feladatnak a megoldása biztosan a globális megol...