Denes Fodor

6603890252

Publications - 23

Performance Comparison of the General, the Dual, and the Joint Sigma Point Kalman Filters on State Estimation of Li-Ion Battery Cells for BMSs †

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

Li-ion batteries, known for high energy and power density, are widely used in electromobility and stationary applications. In these applications a Battery Management System (BMS) ensures safety and longevity by performing functions like cell balancing and protecting against overcharge and over-discharge. Advanced BMSs estimate the battery’s State of Charge (SOC), crucial for determining remaining operating time and safe range. This study compares three Kalman Filter (KF)-based SOC estimation techniques: the general Sigma Point KF (SPKF), the joint SPKF, and the dual SPKF, for state and parameter estimation of a Samsung 18650INR13L Li-ion battery.

Open Access: Yes

DOI: 10.3390/engproc2024079045

A Long Short-Term Memory-Based Deep Learning Digital Twin of a Li-Ion Cell for Battery SOC Estimation †

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

This study aims to implement the digital twin of a Li-ion battery by using real measurement data and to create a deep learning-based SOC (state of charge) estimation solution. In the case of the SOC estimator, a special type of deep learning, so-called long short-term memory (LSTM), was used to increase the capabilities of the estimator. The digital twin and the SOC estimator were created by using MATLAB and MATLAB/Simulink. As a result, the implemented system can accurately simulate the non-linearities of the Li-ion battery and provide a satisfactory estimation of the SOC of the battery.

Open Access: Yes

DOI: 10.3390/engproc2024079016

Performance Comparison of the General the Dual and the Joint Extended Kalman Filter on State Estimation of Li-ion Battery Cells for BMS

Publication Name: 2024 IEEE 21st International Power Electronics and Motion Control Conference Pemc 2024

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

The aim of the work is to compare the performance of the general Extended Kalman Filter (EKF), the joint EKF and the dual EKF for state and parameter estimation of a Samsung 18650INR13L Li-ion battery cell. The used battery model is based on a simplified Randles equivalent circuit equipped with Rs, Rct and Cdl parameters. The initial values of Randles parameters were identified from constant charge, discharge and transient discharge measurements. The performance of the implemented Kalman Filters were compared for the state and parameter estimation of the cell during WLTP test condition. While the general EKF uses only the identified initial values of the parameters, the joint and dual EKF are able to estimate them to compensate for the drift during the operation which leads to more accurate state estimation and compensates the parameters change due to heat and the aging of the cell. From the SOC estimation performance comparison we found out that both the dual and joint EKF perform similarly well, but the dual EKF has about 22% less computational cost which is very significant in the case of the future implementation on a real Battery Management System (BMS) which was the target of this investigation.

Open Access: Yes

DOI: 10.1109/PEMC61721.2024.10726344

Simscape Implementation of a Nonlinear Permanent Magnet Synchronous Machine Model for Sensorless Polarity Detection

Publication Name: 2024 IEEE 21st International Power Electronics and Motion Control Conference Pemc 2024

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

This paper presents the implementation of a novel extended PMSM model in the Simscape acausal modeling subsystem of the widely used Mathworks MATLAB-Simulink numerical simulation environment. The extended PMSM model is based on a quadratic flux-current function that describes the machine's rotor position-dependent and polarity-dependent properties and facilitates the development of signal injection-based sensorless polarity detection algorithms. The implemented PMSM model was validated using simulations and measurements. The presented simulation results include modulated sinusoidal injection and non-modulated square-wave injection which are commonly used carrier signals in sensorless algorithms, and the simulation results were compared to corresponding measurements. A comparison of the acausal modeling approach in Simscape to the causal approach of Simulink is also presented. The implemented PMSM model is open source. The source code and the related data are available on GitHub.

Open Access: Yes

DOI: 10.1109/PEMC61721.2024.10726332

Comparative Analysis of Field Oriented Control and Direct Torque Control Through Simulation in MATLAB Simulink for an Automotive Drive Motor †

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

Field oriented control (FOC) and direct torque control (DTC) are two strategies used in electric motor control, both with their respective advantages and disadvantages. This paper presents a comparative analysis of these two control methodologies, focusing on their application and performance within a MATLAB Simulink (R2024b) environment for an automotive Permanent Magnet Synchronous Motor (PMSM) drive. The models are created with a focus on realistic drive and test parameters. The simulation results are analyzed to highlight the strengths and weaknesses of each strategy and identify use cases where one method may be superior to the other. In conclusion, this paper contributes to the understanding of FOC and DTC by offering a systematic comparison of their features, performance characteristics, and application scenarios for automotive use.

Open Access: Yes

DOI: 10.3390/engproc2024079033

Embedded System Simulation Using Renode †

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

In the automotive industry, the reduction of development costs is of key importance. The development of electrical hardware is an expensive, time-consuming process with a lot of development stages (e.g., prototyping, electrical testing, mechanical testing, lifecycle testing). There is a growing need to increase the cost-effectiveness of the development and testing phases of embedded software using virtualization. Using this method, less prototype manufacturing is necessary since the simulations allow for faster and more effective discovery of a large portion of possible faults without building a hardware prototype. Renode is an open source embedded system simulation framework that facilitates software-based testing. The main goal of this paper is to explore the usability of the framework for automotive applications.

Open Access: Yes

DOI: 10.3390/engproc2024079052

Embedded System Simulation for Electrical Hardware Test Virtualization

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 799-804

Description:

In the automotive industry, the reduction of development costs has a key importance. Also, the duration of the development is a significant aspect. Electrical hardware development is an expensive, time-consuming process with a lot of development stages (e.g., prototypes, electrical tests, mechanical tests, lifecycle tests). Virtualization is an important factor in making electrical component development more sustainable; using this method, less prototype manufacturing is necessary since the simulations make it faster and more effective to find out a large portion of possible faults without building a hardware prototype. The main goal of the paper is to explore the capabilities of seven software solutions that can manage the virtualization of the electrical development toolchain. The simulation environment should manage the simulation of the electrical circuit, including the sensors and loads, the microcontroller, and the execution and debugging of the uploaded program code. The study provides guidance on choosing the proper simulator depending on the simulation focus.

Open Access: Yes

DOI: 10.3303/CET24114134

Testing Embedded Software Functionality Of Safety Critical Brake-By-Wire Systems Based On Vector Toolchain

Publication Name: Proceedings of the 2024 25th International Carpathian Control Conference Iccc 2024

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

Brake-by-wire is an innovative braking system that replaces the traditional hydraulic braking system with an electronic-hydraulic one. The brake-by-wire system is a safety-critical system that requires reliable and efficient communication between the electronic control units (ECUs) in the vehicle. Testing the communication network is critical to ensure the system's safety, reliability, and performance. Vector toolchain provides an efficient and reliable platform for testing the communication network of brake system ECUs. In this research, we present a testing methodology for ECUs in the Vector toolchain environment using Hardware-In-the-Loop (HIL) simulation. The proposed methodology includes the design of test scenarios, the implementation of the test cases, and the analysis of the test results. The results of the research show that the proposed methodology can effectively test the communication network of brake-by-wire ECUs in the Vector toolchain environment and provide insights into the network's performance and reliability.

Open Access: Yes

DOI: 10.1109/ICCC62069.2024.10569260

Enhancing Safety-Critical Brake System Testing with Vector SIL over Complex Vector HIL †

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

Advanced vehicle technologies that substitute or assist the driver are crucial and safety-critical elements, including independently acting electronic control units. A key element of vehicle road safety is its behavior on the road, influenced by various factors such as adhesion and physical forces. Self-activating brake systems, including related sensors and processing units, are vital for modern autonomous vehicles. The complexity of software in vehicle electronic control units (ECUs) has significantly increased, making traditional testing methods inadequate. This paper explores the use of Software-in-the-Loop (SIL) and Hardware-in-the-Loop (HIL) testing methods in an automated test environment to enhance software development and testing processes. It can be demonstrated that there is interoperability between the HIL and SIL systems using the same test case implementation in the Vector CANoe simulation environment. As a result, it can be demonstrated that in the case of a safety-critical function, such as an ABS (anti-lock brake system) control intervention, the ECU control software behaves the same in both the HIL and SIL simulation environments.

Open Access: Yes

DOI: 10.3390/engproc2024079034

Comparison of Coupled Electrochemical and Thermal Modelling Strategies of 18650 Li-Ion Batteries in Finite Element Analysis—A Review

Publication Name: Materials

Publication Date: 2023-12-01

Volume: 16

Issue: 24

Page Range: Unknown

Description:

The specificities of temperature-dependent electrochemical modelling strategies of 18650 Li-ion batteries were investigated in pseudo-2D, 2D and 3D domains using finite element analysis. Emphasis was placed on exploring the challenges associated with the geometric representation of the batteries in each domain, as well as analysing the performance of coupled thermal-electrochemical models. The results of the simulations were compared with real reference measurements, where temperature data were collected using temperature sensors and a thermal camera. It was highlighted that the spiral geometry provides the most realistic results in terms of the temperature distribution, as its layered structure allows for a detailed realisation of the radial heat transfer within the cell. On the other hand, the 3D-lumped thermal model is able to recover the temperature distribution in the axial direction of the cell and to reveal the influence of the cell cap and the cell wall on the thermal behaviour of the cell. The effect of cooling is an important factor that can be introduced in the models as a boundary condition by heat convection or heat flux. It has been shown that both regulated and unregulated (i.e., natural) cooling conditions can be achieved using an appropriate choice of the rate and type of cooling applied.

Open Access: Yes

DOI: 10.3390/ma16247613

Nonlinear PMSM Model Implementation in MATLAB-Simulink for Sensorless Polarity Detection

Publication Name: 2023 International Conference on Electrical Drives and Power Electronics Edpe 2023 Proceedings

Publication Date: 2023-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

This paper presents the implementation of a novel nonlinear PMSM model for signal injection-based sensorless polarity detection algorithm development. The model extension incorporates a quadratic flux-current function to describe the polarity-dependent saliency of the machine. The model was implemented in the Mathworks MATLAB-Simulink environment, which is widely used for numerical simulations of electric machines and drives. The presented simulation results include non-modulated square-wave injection and modulated sinusoidal injection which are commonly used in sensorless algorithms. Furthermore, these simulation results were compared to corresponding measurements, and the comparison between the simulated and measured data is also provided. The models are open source and available on GitHub.

Open Access: Yes

DOI: 10.1109/EDPE58625.2023.10273864

Convolutional Neural Network-Based Tire Pressure Monitoring System

Publication Name: IEEE Access

Publication Date: 2023-01-01

Volume: 11

Issue: Unknown

Page Range: 70317-70332

Description:

Tire pressure has a significant influence on the driving safety of road vehicles; therefore, it is mandatory in many countries to equip all new road vehicles with a tire pressure monitoring system (TPMS). There are two types of TPMSs in use: the direct TPMS (dTPMS) and the indirect TPMS (iTPMS), both of which have made significant improvement in the last decade. The most accurate iTPMS methods used in commercial vehicles apply the Fourier transform on wheel speed sensor (WSS) signals and extract the pressure-dependent eigenfrequency by utilizing center of gravity (CoG) or peak search (PS) methods, the research focus is shifting towards model-based and artificial intelligence-based methods. In this paper we propose a novel advanced iTPMS method based on modern signal processing and a convolutional neural network (CNN) for eigenfrequency detection. The proposed iTPMS method uses the hybrid wavelet-Fourier transform in combination with a CNN trained for pattern recognition-based eigenfrequency detection, and according to experimental results, it outperforms the commercially most frequently used Fourier transform and CoG method combination both in terms of computational requirement and accuracy.

Open Access: Yes

DOI: 10.1109/ACCESS.2023.3294408

The Key Role of 3D Printing Technologies in the Further Development of Electrical Machines

Publication Name: Machines

Publication Date: 2022-05-01

Volume: 10

Issue: 5

Page Range: Unknown

Description:

There is a strong general demand for the permanent improvement of electrical machines. Nowadays, these are at their near maximum potential, and even small further improvements can only be achieved with great effort and high cost. The single solution should be a paradigm shift in their development, by using radically new approaches to topology, materials, and fabrication. Therefore, the application of diverse 3D printing techniques for advanced fabrication in this field is inevitable. Therefore, these new approaches are receiving a great deal of attention among electrical machines designers. In the paper, the possible applications of these new fabrication technologies in the field of electrical machines are surveyed. The focus is set on emphasizing the advancement over the traditional manufacturing approaches.

Open Access: Yes

DOI: 10.3390/machines10050330

Permanent Magnet Synchronous Motor Model Extension for High-Frequency Signal Injection-Based Sensorless Magnet Polarity Detection

Publication Name: Energies

Publication Date: 2022-02-01

Volume: 15

Issue: 3

Page Range: Unknown

Description:

In this paper, a novel extended permanent magnet synchronous motor model is presented that incorporates a quadratic flux-current function to represent the polarity-dependent saliency. The proposed model enables the design of sensorless polarity detection algorithms required by the initial position detection of permanent magnet synchronous motors. The novelty of the model is that it integrates the polarity-dependent saliency into the traditional machine model and introduces a new machine parameter, the polarity-dependent saliency coefficient, to specify the Hessian matrix of the flux-current function. A measurement method is presented for determination of the elements of the Hessian and the polarity-dependent saliency coefficient. The solution of the model is given for high-frequency sinusoidal pulsating voltage injection. Experimental results show that the proposed extended model accurately predicts the amplitudes and phases of the second harmonics of the motor currents, which are the carriers of the polarity-dependent information. This information enables a current measurement-based polarity detection algorithm using the phase difference between the fundamental and second harmonic of the apparent d-axis current. Both the presented measurement data and the proposed model show that injection in the d-direction is optimal for polarity detection.

Open Access: Yes

DOI: 10.3390/en15031131

Comparison of square-wave and sinusoidal signal injection in sensorless polarity detection for PMSMs

Publication Name: 2022 IEEE 20th International Power Electronics and Motion Control Conference Pemc 2022

Publication Date: 2022-01-01

Volume: Unknown

Issue: Unknown

Page Range: 583-589

Description:

This paper compares the non-modulated square-wave voltage injection-based and sinusoidal voltage injection-based polarity detection methods applicable in sensorless PMSM drives. A quadratic PMSM model extension is presented that serves as a basis for the polarity detection techniques. The comparison includes the polarity-dependent current components produced by the injected signals, the design parameters related to the injected signal features and their effect on the probability of correct polarity detection. The performance differences and possible application areas are also discussed.

Open Access: Yes

DOI: 10.1109/PEMC51159.2022.9962876

Low speed operation of sensorless estimators for induction machines using extended, unscented and cubature kalman filter techniques

Publication Name: International Conference on Electical Drives and Power Electronics

Publication Date: 2019-09-01

Volume: 2019-September

Issue: Unknown

Page Range: 279-285

Description:

In this study, three feasible speed sensorless estimators of induction machines are presented by using extended, unscented and cubature Kalman filter algorithms. The estimators are based on an augmented non-linear state-space model of these machines, which describes the dynamics in stationary reference frame with six state variables. As an important part of the estimator design, an observability study is provided for the nonlinear model and an observability condition is formulated as well. The estimators are compared experimentally around zero stator frequency with respect to the speed estimation performance. However, the estimators are investigated only in open-loop and without external load disturbance.

Open Access: Yes

DOI: 10.1109/EDPE.2019.8883936

Measurement of Pedestrian Targets in Terms of Radar Cross Section

Publication Name: Saci 2023 IEEE 17th International Symposium on Applied Computational Intelligence and Informatics Proceedings

Publication Date: 2023-01-01

Volume: Unknown

Issue: Unknown

Page Range: 363-368

Description:

In terms of vehicle radars, the most important properties of targets are speed, distance, and radar cross section. Based on the Radar Cross Section (RCS), the type of the object can be identified with a good approximation: pedestrian, bicycle, car, truck even in extreme weather conditions. A radar cross section measures the reflectivity of an object and its numerical value is equal to the area of the cross section of a conducting sphere with the same reflectivity. Its value depends on the material and shape of the object, the angle of illumination, and the ratio between the wavelength and the size of the object. The article presents a measurement system for radar targets, the main component of which is an automotive radar. In addition, the evaluation software for the measurement system, which was created in the MATLAB / SIMULINK environment, will be presented. The measurement system was used to perform various measurements on the ZalaZONE Automotive Proving Ground (Zalaegerszeg, HUNGARY), the evaluation of which will be presented. The purpose of the measurements is to collect information about the radar cross-section values of pedestrians at different distances from the vehicle and dummies simulating them. A comparison of different pedestrians is presented. After that, we will show how even if a puppet is formally similar to a pedestrian, the RCS can show a different value.

Open Access: Yes

DOI: 10.1109/SACI58269.2023.10158601

Theoretical Investigation and Simulation of a Brake-by-Wire Based Bicycle Wedge Brake

Publication Name: Lecture Notes in Mechanical Engineering

Publication Date: 2026-01-01

Volume: Unknown

Issue: Unknown

Page Range: 107-118

Description:

In today’s vehicle industry “X-by-wire” technologies gain significant importance, especially in full-electric vehicles. This paper demonstrates the first steps of an electromechanical bicycle wedge brake design that uses brake-by-wire technology. The paper discusses the importance of Anti-lock Brake Systems (ABS) and Brake-by-Wire (BBW) technologies in the bicycle industry and summarizes how the technologies improve rider safety. Then we do a technical investigation by establishing a Model-Based Design workflow for developing a first-principle ABS control for electronic wedge brake applications. First, We establish a longitudinal model of a bicycle, allowing for a detailed investigation of wheel-lockups. After obtaining a baseline bicycle model we implement a control algorithm to prevent wheel-lockup during braking. The effect of the control algorithm on the braking distance of the bicycle is also investigated. After concluding the effects of the ABS brake systems for bicycles we summarize the next steps for continuing the design process of the brake system development.

Open Access: Yes

DOI: 10.1007/978-981-96-6452-8_9

Verilog-A Implementation of a Nonlinear Permanent Magnet Synchronous Machine Model for Sensorless Polarity Detection

Publication Name: Edpe 2025 37th International Conference on Electrical Drives and Power Electronics and 12th Joint Croatia Slovakia Conference

Publication Date: 2025-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

In this paper, we present the implementation process of a novel extended PMSM model in Verilog-A. The extended PMSM model is based on a quadratic flux-current function that describes the machine's rotor position-dependent and polaritydependent characteristics, enabling the development of signal injection-based sensorless polarity detection algorithms. The Verilog-A module was compiled using OpenVAF, simulated with Ngspice, and integrated via the Qucs-S frontend. Validation was carried out through comparison of simulations and corresponding measurements of non-modulated square-wave and modulated sinusoidal signal injection, two commonly used carrier signals in sensorless control. Simulation results showed good agreement with measurements. The implemented PMSM model is open source. The code and related data are available on GitHub.

Open Access: Yes

DOI: 10.1109/EDPE66853.2025.11224147

Driver Focused Comparison of Field Oriented Control and Direct Torque Control using MATLAB Simulink Simulations

Publication Name: Edpe 2025 37th International Conference on Electrical Drives and Power Electronics and 12th Joint Croatia Slovakia Conference

Publication Date: 2025-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

This paper presents a comparison of two widely used motor control strategies namely field oriented control (FOC) and direct torque control (DTC). They both have their advantages and disadvantages that make them a suitable choice for use in a vehicle drive system. This paper compares these two implemented in a MATLAB Simulink simulation using an automotive Permanent Magnet Synchronous Motor (PMSM). The motor and test parameters are chosen to be realistic from a human driver point-ofview. Simulation results are analyzed to highlight the differences between the two strategies and identify cases where one outperforms the other. In conclusion, the paper shows the effects of the differences and the general characteristics of the simulation results in a realistic case on a human driver as the user of the PMSM in an automotive drive. The paper contributes valuable insight in the classic comparison of these two strategies for automotive use.

Open Access: Yes

DOI: 10.1109/EDPE66853.2025.11224164

Developing Longitudinal Vehicle Dynamics Model of Electric Bicycles for Virtual Validation of Active Safety Systems †

Publication Name: Engineering Proceedings

Publication Date: 2025-01-01

Volume: 113

Issue: 1

Page Range: Unknown

Description:

The increasing adoption of electric bicycles (e-bikes) has led to a growing need for advanced active safety systems, such as anti-lock braking systems (ABSs), to enhance rider safety. In recent years, both hydraulic and electromechanical ABSs were researched. To support the development and validation of these systems, this paper presents a longitudinal vehicle dynamics model of an electric bicycle. The model captures key physical interactions, including drivetrain, transmission, braking, and tire–road contact, to accurately simulate longitudinal motion. By leveraging this model, future studies can perform virtual validation of active safety components in a controlled and repeatable environment, reducing the dependency on costly and time-intensive physical testing. The proposed model lays the foundation for a model-based design approach, enabling early-stage performance assessment and optimization of safety-critical functions in electric bicycles.

Open Access: Yes

DOI: 10.3390/engproc2025113073

Development of an Automated Solution for the Error Analysis of MATLAB/Simulink-Based Digital Twins †

Publication Name: Engineering Proceedings

Publication Date: 2025-01-01

Volume: 113

Issue: 1

Page Range: Unknown

Description:

This study aims to analyze various methods, including AI, that can be used to optimize error analysis in digital twins and highlight the advantages and disadvantages of these analysis methods. Furthermore, the study aims to present an automated solution for error analysis of MATLAB/Simulink-based digital twins. This solution can make the error analysis more efficient without the use of AI, meaning that it can be used even if the digital twin is not appropriately known, which can be a considerable advantage in the current automotive industry, where complex digital twins are commonly used for the development and optimization of E/E systems during different types of in-the-Loop simulations.

Open Access: Yes

DOI: 10.3390/engproc2025113049

Wheel-Speed-Sensor-Based Spectral Classifier for Road Surface Roughness

Publication Name: IEEE Open Journal of Vehicular Technology

Publication Date: 2026-01-01

Volume: 7

Issue: Unknown

Page Range: 829-843

Description:

In this paper, we propose a novel signal processing method for road surface roughness classification exclusively from wheel speed sensor signals. Road surface quality has a significant impact on fuel consumption and driving safety. Traditionally, it has been measured using specially equipped vehicles and, more recently, shared via cloud-based infrastructure; however, such data can be unavailable or quickly become outdated, making onboard solutions essential. We analyzed a large wheel speed sensor dataset from various test maneuvers to determine how road surface roughness influences spectral characteristics under different conditions, including changes in speed, tire pressure, payload, and tire type. The proposed road surface roughness classifier uses only wheel speed sensor signals. It selects signal segments appropriate for processing based on driving conditions and computes their order spectra. The number and relative power of the spectral peaks within the identified interval of interest of the order spectrum are related to road surface roughness. The implemented classifier is capable of distinguishing between rough and smooth road surfaces based on the number of peaks in the interval of interest. The overall accuracy of the implemented road surface roughness classifier was 87.4%.

Open Access: Yes

DOI: 10.1109/OJVT.2026.3656339