Electro-Thermal Model of Liver Tissue and its Approximation

This paper deals with the proposal of the approximation method of complex organic tissues (in this example liver) for electro-thermal simulation. The main objective of the proposed approximation is to reduce the required computational power for electro-thermal simulation of given issue. The approximated parameters are meant to be used in three-dimensional finite element simulation models. Verification of proposed approximation is given by the comparison of electrical current distribution within complex model of liver tissue and approximated one

Wireless (power transfer) transmission of electrical energy (electricity) intended for consumer purposes up to 50 W

This project deals with Power Semiconductor Systems PSS for wireless transmission of electricity to the power of 50~W with regard to the distance and transmission efficiency. We decided to use electromagnetic resonance for electrical energy transmission. For experimental verification, we have wound two coils of identical dimensions. At a given power transmission solutions, we obtain the highest efficiency η = 70% at a distance of 5 cm, where the transmitted power was 48

Wireless Power Transmission System for Powering Rotating Parts of Automatic Machineries

This paper deals with the analysis of a suitable compensation topology of a wireless power transmission system for powering the rotating parts of modern automatic machine tools. It summarizes the important properties of the serio-parallel compensation topology suitable for this application and demonstrates a detailed mathematical derivation using the first harmonic approximation. The paper details the industrial implementation of the system in a specific automatic machine tool application and demonstrates the strong technical advantages of the proposed design. Important theoretical conclusions and technical assumptions made when considering the system layout are verified by experimental laboratory measurements and the final deployment of the technology in the professional tool DMU 40 eVo linea

A novel seismocardiogram mathematical model for simplified adjustment of adaptive filter

Nonclinical measurements of a seismocardiogram (SCG) can diagnose cardiovascular disease (CVD) at an early stage, when a critical condition has not been reached, and prevents unplanned hospitalization. However, researchers are restricted when it comes to investigating the benefits of SCG signals for moving patients, because the public database does not contain such SCG signals. The analysis of a mathematical model of the seismocardiogram allows the simulation of the heart with cardiovascular disease. Additionally, the developed mathematical model of SCG does not totally replace the real cardio mechanical vibration of the heart. As a result, a seismocardiogram signal of 60 beats per min (bpm) was generated based on the main values of the main artefacts, their duration and acceleration. The resulting signal was processed by finite impulse response (FIR), infinitive impulse response (IRR), and four adaptive filters to obtain optimal signal processing settings. Meanwhile, the optimal filter settings were used to manage the real SCG signals of slowly moving or resting. Therefore, it is possible to validate measured SCG signals and perform advanced scientific research of seismocardiogram. Furthermore, the proposed mathematical model could enable electronic systems to measure the seismocardiogram with more accurate and reliable signal processing, allowing the extraction of more useful artefacts from the SCG signal during any activity.Web of Science1115art. no. 244

Improving qualitative parameters of LLC converter using a perspective semiconductor and magnetic components

This paper has been realized in order to show simplified design procedure on how to meet the standards for dc-dc converters, which are being constantly increased. The paper deals with improvement of qualitative parameters of LLC converter. Using evaluations methods Figure of Merit, we select optimal components suitable for high-frequency applications with high power density, where we want elevate the significance of perspective of semiconductors GaN, SiC and modern magnetic materials. The main advantage of using FoM assessment technique for certain system's components is the elimination of simulation and physical experiments for effectivity evaluation. In conclusion, a comparison of converter considering standards ENERGY STAR defining the efficiency parameters of the converter at different load is provided. After it also comparisons of the efficiency using diode rectifier and synchronous rectifier on the secondary site are given

Analytical Method for Compensation Choke Geometry Optimization to Minimize Losses

The article presents an analytical method for optimizing the geometry of the magnetic core of a three-phase compensation choke. The method describes the process of identification the fringing magnetic fields and the corresponding magnetic reluctances of the magnetic core, the flux density calculation even in the case of the core supersaturation and the total losses estimation. It shows finding the trade-off between the size/weight of the inductor and the magnetic core with respect to the overall losses and demonstrates their minimization. The mathematical model for the flux’s identification is based on a standard iterative calculation using the analogy to electrical circuits but includes a new approach to the calculation of fringing magnetic fields caused by the air gapped magnetic core. The presented method is verified by the finite element method (FEM) using the engineering calculation software ANSYS

Wireless power transfer system design methodology - analysis, design, verification

The paper briefly discusses simplified proposal of the design methodology, which suites for wireless power transfer system development. For this purpose, the most important aspects related to standards and regulations are initially discussed, while focus is given on automotive segment, i.e. charging systems. Discussed are topics related to principal design procedure, which are analyzed regarding issues related to electromagnetic design of coupling coils. Related to power electronics concept, recommendations are given on topology selections focusing on proper connection to the grid. Given design procedure is finally verified by laboratory measurements measurement, whereby efficiency of wireless power transfer is key identified variable

Global Simulation Model Design of Input-Serial, Output-Parallel Solid-State Transformer for Smart Grid Applications

This paper provides an overview of an early attempt at developing a simulation model on a solid-state transformer (SST) based on input-serial and output-parallel (ISOP) topology. The proposed SST is designed as a base for a smart grid (SG). The paper provides a theoretical review of the power converters under consideration, as well as their control techniques. Further, the paper presents a simulation model of the proposed concept with a PLECS circuit simulator. The proposed simulation model examines bidirectional energy flow control between the medium-voltage AC grid and DC smart grid, while evaluating power flow efficiency and qualitative indicators of the AC grid. After the completion of design verification and electrical properties analysis by the PLECS simulation models, the synthesis offers recommendations on the optimal layout of the proposed SST topology for smart grid application

Figure of Merit of Semiconductor Structures Determination of the impact on the system efficiency of LLC converter

This article has been realized in order to show simplified design procedure on how to meet the standards for dc-dc converters, which are being constantly increased. Hence we decided to analyze several generations of power semiconductor MOSFET and diode structures. With the use of simulation we've analyzed power losses (switching losses and conduction losses) during Zero Voltage Switching commutation mode. Parametric simulations were carried out at the conditions that meet electrical parameters of switched mode power supplies suited for distributed power systems. The aim of determination of switching losses at different conditions during ZVS mode is to see, whether determination of figure of merit (FOM) parameter can be considered as reliable indicator for proper device selection for target application. Consequently the FOM parameter for selected types of transistors and diodes in terms of several FOM methodologies has been determined. This parameter shall represent a measure of semiconductor suitability for high frequency power transistor application. The relevancy of FOM parameter will be finally evaluated in the way of efficiency (one of qualitative indicator) investigation of proposed LLC converter. Based on the evaluation of simulation analysis and on efficiency investigation of proposed LLC converter the confirmation of FOM relevancy will be confirmed