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This paper deals with high frequency analysis of spiral inductors, used in microelectronics circuits, to optimize their configuration. Software developed, designed, and implemented by the authors for nano and micrometre spiral inductor high frequency analysis, named ABSIF, is presented in this paper. ABSIF determines the inductance, quality factor, and electrical parameters for square, hexagonal, octagonal, and circular spiral inductors and their configuration optimization for energy efficiency. ABSIF is a good tool for spiral inductor design optimization in high frequency applications and takes into account the imposed technological limits and/or the designers’ constraints. A set of spiral inductors are considered and analysed for high frequency values using ABSIF, and the results are presented in the paper. The validation of ABSIF was completed by comparing the results with those obtained using a similar commercial software, Sonnet LiteTM, which is dedicated to high frequency electromagnetic analysis.

Traditional wireless power transfer systems typically adopt the single-frequency control method to ensure a constant output voltage and current for different applications. This paper presents a different side of the control circuit of a wireless energy transfer system, i.e. input is made with two frequencies aiming to optimize the wireless energy transfer.The purpose of this paper is to show how it can be increased the efficiency of a wireless power system, in comparison with the traditional wireless power transfer systems with a single command frequency. An experimental prototype will be buit in order to verify the effectiveness of the proposed wireless energy transfer system and the control method.

Nowadays operation of the power distribution networks is constrained by the currently active regulations but also by some other factors that are conditioned by its beneficiaries impact or by economical restrictions. In this work the second category of factors is tackled by identifying and forecasting in an optimal approach one of the most important terms in indirect control of the energy contour which is impacted by the own technical consumption.Own technical consumption in distribution grids is one of the most relevant performance indices related to the efficiency operation and sustainable development of power grids. For this reasons, it is considered as an essential monitoring parameter in regulatory and supervising governmental agencies in energy domain. At this level of importance the power distribution operators are willing to determine and to estimate the evolution of this parameter for their internal needs as a factor in decision making and for reporting to the regulatory organizations. The paper’s main goal is focused on development and analysis of this performance index forecasting. Two approaches are evaluated, namely the data series based linear regression model estimation and a novel multi-criteria optimization forecast method.In order to validate the proposed approaches, a case study is performed and the outcome results and analysis are presented. The proposed methodology and how the most relevant obtained results can be deployed and implemented by the industry are illustrated.

IC’s power devices are widely used in many applications like switched-mode power supplies, power drivers for mechanical actuators, etc., being subjected to repetitive power pulses. The Active Power Cycling (APC) influences the reliability of IC’s, hence the failure rate. The failure mechanisms observed in MOSFETs power devices based on contacting clip technology [3] are solder fatigue and metallization layer degradation. The difference between the Coefficient of Thermal Expansion (CTE) of different materials can induce high deformations in chip metallization, like wrinkles at the top power metal layers. It is well known that the temperature swing is responsible for the IC’s degradation, but many other parameters e.g. geometrical dimensions, material properties etc., have an important impact too. This paper studies the impact of geometrical dimensions on thermal-induced stress and deformations by a contact clip on a typical MOSFET metalization structure.

Today, in the age of 4G and 5G technologies, the continuous development of high-tech devices through their minimization and various forms of design for their components that need to comply with EMC standards, make the analysis and design of EMI filters to be a research topic of great interest that will certainly stay that way for many more years. In this context, the present paper proposes the analysis of the influence of the geometric shapes of the elements that compose a planar EMI filter on its parameters. On one hand, we will follow the self-parameters of the component elements, and on the other hand, the minimization of the parasitic parameters will be followed. The analyzes will be performed on a low pass filter, which is the main element of the filter for the suppression of the electromagnetic interferences.

The wireless power systems of millimetre dimensions are nowadays used for a wide range of high technology applications. In this paper we aim to extract the planar spiral inductors parameters to optimal design them for the design of a wireless power supply system used to supply the peacemaker or other similar devices. The planar spiral inductors are analysed first to extract their specific parameter. Then the influence of the ferrite on the spiral inductors parameters is analysed to improve the inductor performances by increase its inductance. Next using the optimized inductor, a wireless power supply system is designed and 3D numerical modelled to also extract its parameters. Different distances between emitter and receiver inductors are considered trying to estimate the real possible distance that can exist between them if they will form the wireless power supply of a peacemaker. Finally, we analyse the influence of ferrite, considering different thicknesses, also on the wireless system’s parameters, aiming to increase them for improvement of device performances.

This interlaboratory comparison is performed for two reasons: to ensure the repeatability of testing amongst EMC laboratories concerning specific test methods and to evaluate the testing capabilities of these laboratories. The purpose of this paper is to present the application of an interlaboratory comparison method for electromagnetic fields produced by power supply systems, involving two laboratories. An electromagnetic field generator with a frequency of 50 Hz, which is moved from one laboratory to another, is used in order to obtain the data for the final assessment. The results obtained were based on the three-point measurement method in accordance with the standard IEC 61786.

Permanent magnets are found in more and more devices in the industry and increasing their functional performance leads to the efficiency of these devices that contain them. The aim of this paper is the analysis by numerical modelling of different sets of ring permanent magnets to determine the optimal positioning of the magnetization directions in order to obtain an uniform magnetic field on their surface. The analysis of different sets of ring permanent magnets by numerical modelling, starting from simple structures formed by a ring magnet and progressively reaching complex structures formed by five magnets to determine the influence of magnetization direction on specific field quantities in order to find the optimal orientation of the magnetization direction to obtain an uniform magnetic field on the outer surface of the magnets. Two sets of ring magnets are analysed and compared. In the first set the same magnetization direction is considered in all magnets, and in the second set the magnetization direction will be different.

The purpose of this paper is to analyze the influence of different constructive elements of a Vivaldi antenna on its characteristic parameters (directivity, gain, S parameters). An initial antenna is considered and the substrate material, width of the microstrip line used as feeding and the shape of the planar metallic antenna are then modified. The antenna is modeled with a high frequency numerical modeling program, namely HFSS. The values of the parameters obtained for the different structures following different modifications will be compared with the ones of the initial antenna and an optimum antenna will be determined.

The planar Yagi-Uda antennas find their applicability in many devices around us. They produce electric and magnetic field emissions, which can be harmful to humans on long exposure. In this context, in the first part of this paper is analysed, by high frequency numerical modelling, a Yagi-Uda antenna made in planar electromagnetic technology to determine specific field quantities (directivity, S-parameters, electric and magnetic fields), and respectively the antenna parameters. In the second part, the antenna is modelled in the presence of the human head to determine the influence of the human head on the specific quantities of the antenna (directivity, S-parameters), respectively the influence of antenna emissions on the human head (SAR, electric and magnetic fields). The antenna will be implemented in the presence of the human head by positioned the human head in the emission direction of the antenna for the analysis of the influence of the SAR, electric and magnetic fields on it. The results obtained will be compared and reported to the standards and legislation in force on human occupational exposure, to verify that the limits are met.

Patch antennas are a type of antenna used in a lot of domains in our days, from GPS, radars and mobile phones to cancer tissue detection, spaceships, satellites and missiles. Their geometrical parameters and feeding type influence their functionality and characteristic parameters. This paper focuses on high frequency numerical modeling of circular and rectangular patch antennas with two different types of feeding. Four different types of antennas are high frequency analyzed to find their characteristic parameters. A comparation of the results obtained for the parameters of circular and rectangular patch antennas for different feeding types is detailed in order to find their influences on the frequency range in which the antenna is working.

Nowadays more and more electronic and electrical devices contain spiral coils made in planar technology. Thus, the transition from single layer to multi-layer spiral coils is inevitable. The purpose of this paper is to determine the inductance of multilayer spiral coils of different geometries (square, circular, hexagonal and octagonal) and configurations that produce much higher performance. The use of multilayer spiral coils allows a flexibility to choose the desired size with the possibility to change both the number of turns and the number of layers. Therefore, by comparing numerous coil configurations presented in this paper, the correctness of the proposed solutions for determining the inductance of multilayer spiral coils was demonstrated by numerical modeling, experimental measurements and analytical calculations starting from monolayer spiral coils, where the inductance calculation was based on the formula developed by researcher S.S. Mohan using fundamental principles of electromagnetism.

This article presents an approach to develop an electrical micro-grid with more than one renewable energy source. The micro-grid is considered as a discrete power system composed of distributed energy sources and different kind of system loads. The loads of the micro-grid can operate in alongside with the grid or can switch to other power system to supply continually the electrical energy, otherwise the micro-grid power system can switch to an accumulating reserve, such as battery banks, fuel cells or other allocated reserve. Operation of the micro-grid relies on demand, storage, and energy generation management. In this case the energy supply comes from the renewable energy system or from the accumulated energy reserves. The proposed development comprehends the use of a series of data, from the monitoring and data acquisition unit, process the data by constructing and train the neural network with this data. After the validation of neural network error rate, we use the network function to estimate a short term time series prediction. The data input is a daily solar energy value, which was measured a period of time. From this data we try to forecast the energy production value for the next day. The predicted value may serve to control the renewable energy based power system, in function of energy demand. In the studied system we have a combined hybrid power generation unit, a solar photovoltaic and a micro hydro, where the main sub system is the solar photovoltaic and the micro hydro is serving as an accumulative reserve, partially controlled by the estimated predicted data.

In the past, operation of automotive equipment was not susceptible to electromagnetic disturbances. Then with the increase in the number of electronic components and of electromechanical devices from automobiles which are operating at high frequencies, transient phenomena occur which produce electromagnetic interference that may influence the correct function of some equipment. So, immunity is the issue that needs to be considered and solved during the design of the automotive system. This paper presents a study that analyzes the importance of engine immunity used in automotive applications in accordance with EMC standards.

Finding a qualitative model to study the thermo-mechanical effects inside the Metal-Oxide-Semiconductor power Integrated Circuits (MOS power IC's) is needed even from the design stage of such devices. The high number of geometry details contained by these devices, especially at the level of the metallization system, rise difficulties in the Finite Element Method (FEM) analyze, thus some simplifications are needed. In this paper a simple method of geometry details reduction is proposed, in order to eliminate some geometrical details such as vias between two different metal layers. While the geometry details are simplified, the thermo-mechanical behavior is assessed on a simple Double-Diffused MOS (DMOS) substructure with an open source software (Code_Aster) based on FEM. In order to understand the influence of vias at the metallization level, temperature and strain distributions are compared for three different cases with vias, no-vias and equivalent materials properties block respectively. The no vias model approach capture with less computational effort and good accuracy the thermal induced metal deformation.

This article presents an electromagnetic study of conducted and radiated disturbances produced by the lamps. The analysis was performed on four types of lamps, the most common lamps: incandescent, halogen, compact fluorescent (CFL) and light-emitting-diode (LED), with the same luminous flux to determinate the conducted emissions and to determinate the radiated emissions. The experimental results and comments related to the limits for each type of lamp, especially the determination of conducted and radiated disturbances according to EN 55015 Standard, are also presented.

The wireless power systems are becoming increasingly used for a wide range of applications. The wireless charge of newest gadgets is a new technology in all the world in our days. The purpose of this paper is to design such a system using planar spiral inductors. The planar spiral inductors have a wide range of applications in industry. The planar spiral inductors, that will be used to design the wireless power supply system, are first modeled to extract their parameters. The inductors are parametric analyzed to optimal design and the optimized spiral inductors are practical constructed. Finally, they are used to design and construct a wireless power supply system.

Starting from an induction plate often encountered in kitchen households, different geometries for this device will be numerically modeled in order to analyze their functionality, ohmic losses, magnetic induction and current density. Also, the effects of parameter variation will be highlighted. The model was analyzed in 2D and also in 3D. The varied parameters were number of turns, diameter of the conductor from which the turns are constructed, the shape of the conductor and the material from which the recipient where the food is heated is made of. The novelty of this study is the ohmic losses approach and the software used for the simulation. The representations can be also used in educational purposes.

The objective of this paper is the implementation through numerical modelling of Halbach permanent magnets for the determination of the optimum magnetization directions in order to obtain a uniform magnetic field around the set of Halbach permanent magnets. For this study the magnetic induction distribution, magnetic field intensity and current density for the studied magnets are compared. From the different types of Halbach arrays, the linear array represents the subject of this study.

This paper represents a study on bowtie planar antennas. Varying the shape of the bowtie patch and considering different dielectric materials to be a part of the antenna construction, their influence on the specific parameters of the antenna is determined. The scattering parameters (S parameters), gain and directivity are the parameters which were determined and analyzed in order to draw some conclusions. The structures are analyzed in the frequency range 1-10 GHz.

The aim of present research was the experimental characterization of the radiated power and its dynamics in the near-field of mobile terminal during its use in various voice and data application services belonging to either Universal Mobile Telecommunications System (UMTS) or Long-term Evolution (LTE) communication technologies. The quantification of the realistic electromagnetic exposure of human user was done by offering a complementary, non-standardized method that enables a comprehensive dosimetric understanding of radiation impact. Statistical analysis was applied over the radiated power levels measured in different wireless communication situations followed by average and worst case exposure highlighting. Highest power levels were measured for uploading-type applications running under both UMTS and LTE networks. Among UMTS voice application services, VoIP-radiated power levels were on average 1.4 higher than those for VoCS services. The multiplication factor of the radiated power in LTE vs. ...

Patch antennas are highly used in the last few years in domains like spaceships, satellites and missiles, cellular phones, radars, GSM, wide area computer networks and also wireless local areas. This is the result of their advantages, namely the small dimensions and weight, their low cost, ease of use, ease of integration in other circuits and capability to operate at 2 or 3 frequency values. Their disadvantages, among which low efficiency, high quality factor and a narrow bandwidth must be improved. In order to do so, we must previously study the influence of different parameters on their functioning. In this paper, three different feeding types will be implemented on patch antennas and the resulting parameters will be compared and analyzed. Also, different operating frequencies will be taken into account in order to determine the dimensions of such an antenna. Considering the Rogers RT Duroid 5880 dielectric and its standard thicknesses patch antennas will also be modeled and parameters like S parameters, the bandwidth, directivity, gain will be analyzed.

The automotive industry must be aware of the fact that any existing or newly created electric or electronic device is required to meet numerous electromagnetic compatibility (EMC) requirements. For example, one of the requirements must ensure that electrical and electronic systems do not emit electromagnetic emissions or noise excessively and are immune to emissions from other systems. This paper explores the emissions through conduction of electrical and electronic devices used in the automotive industry, using voltage and current probe methods, and highlighting ways to reduce emissions through conduction.

Technological development put international organisations to effort in order to issue and continuously reassess standards concerning electromagnetic radiation protection issues. Protection standards have to be continuously reviewed as new data become available. This article provides a brief overview of updates implemented by the latest available protection standards. Currently, standards do not incorporate appropriate safety factors for protection against long-term effects of exposure to electromagnetic fields, thus protection is provided only for the established short term effects of electromagnetic fields on the human body. However, there is still a great deal of questions related to differences in limitations set by international organisations that have issued recommendations for personnel protection against electromagnetic fields.

This paper presents a study regarding the conducted electromagnetic emissions of a wireless power system. Due to the fact that in the last few years there have appeared a lot of devices with wireless systems, it must be in accordance to the EMC norms. In this context, were performed tests to ensure that analyzed wireless power system meet the EN 55032 standard limits. Based on the test results, was designed a filter to reduce conducted electromagnetic emissions and improve the performance of the wireless power system.

The paper emphasizes a study regarding the efficiency of the passive loops usage for the mitigation of the magnetic field values in the neighborhood of high voltage overhead power lines. In the first part of the paper the basic principles of the suppression method are introduced. In the second part of the paper analytical computation results are presented and discussed. The efficiency of the proposed mitigation solution is outlined. Final conclusions end the paper.

The problem of reducing electricity consumption by using energy saving lamp type LED (Light-Emitting Diode), CFL (Compact fluorescent lamp) or UV (Ultra Violet) took unprecedented proportions in all EU countries. Compared to traditional incandescent lamp, the advantages of energy saving lamps in terms of efficiency that the environmental impact is undisputed. We find this type of energy saving lamps in all fields, we have UV lamps used for ambient or in beauty salons, CFL is finded in any household and LED lamps are found from at lights illuminating buildings to automotive taillights. The disadvantages of these types of lamps can be both in terms of emissions of conduction and radiation emissions. The radiated emission can also affect the human health. This paper presents three different methods that can assess the electromagnetic radiation produced by the UV lamps and LED lamps compared to the level of human exposure.

Increasing the number of electric/electronic devices powered with electric power, has led to a series of different chargers and a mixture of wires spread through the house or office. For a long period of time, the concept of charging without any direct connection through wires was avoided, but the last few years show an increased interest to make the loading with electrical power more flexible and easier to use. In this context, the work has as its main objective the practical realization and analysis of power systems for electrical and electronic devices. Therefore, it is necessary to create and analyze multiple types of spiral inductors to achieve a feeding device with higher performance.

Due to ongoing push of technology to smaller dimensions and higher computational speed of the electronic devices, a higher heat generation on device is obtained, increasing the thermal management challenges. This paper proposes a study of the electro-thermal behavior in electronic power devices and the optimization of the cooling system in order to increase the lifetime of the device. Different heat-sink designs for L298N Dual H-Bridge are proposed in this article. For each testing design of the heat sink two problems need to be solved: the electrical process model, which provides the power dissipation of the system, and the thermal process model, which provides the temperature distribution. The thermal analysis results and the optimal design of the heat sink are modeled using CAD/CAE specialized tools.

DC Motors are important components for the automotive industry, but they're also a strong electromagnetic interference (EMI) source. Knowing this problem, conducted emission (CE) tests and Voltage Transient Emissions (VTE) tests were carried out along the power lines of the motor according to the standards CISPR 25 and 7637-2. Conducted emissions from the components which are to be placed on an automotive are measured in a perfect stable environment, although they operate in a continuous vibration environment. In this study we induced several vibrations and evaluated their effect on the conducted emissions, giving thereby an overview on how the vibrations of the vehicle influences the electromagnetic compatibility (EMC) of the components.

Thermo-mechanical stress accumulation in the power electronic integrated circuit (PIC) devices influences their lifetime and reliability. In order to determine both the temperature and the stress accumulation, numerical simulation is a very important tool in the design of PIC devices for quantifying and enhancing their lifetime and reliability. An open source solution integrated in Salome-Meca and Code_Aster based on the finite element method (FEM) is used in this paper to analyze the thermo-mechanical behavior on a simple metal-semiconductor structure, which is typically found in a PIC. The computational time and accuracy of the simulations results is improved by finding the optimal mesh configuration. A convergence study is computed for five different cases by progressively reducing the size of the discretization elements (hence, increasing the number of mesh elements) in the area of interest. The results for an optimal relative error and computational time are compared with the results obtained using the commercial software Comsol. The simulated mechanical stress is compared with similar results reported in literature.

The electromagnetic field interferences (EMI) can influence both human health and functioning of electrical appliances. An EMI map is an important instrument for monitoring the health exposure limits versus the standards. In order to draw an EMI map measurement methodologies and advanced computational models are required. In case of high voltage (HV) and or medium voltage (MV) substations the numerical simulation has several advantages because it does not require investment in measurement devices and operative personnel and can easily analyze complex working scenarios covering both substation yard and its neighborhoods. Examples of numerical simulations are presented on the 3D model of the 110/20 kV substation named Biharia in order to visualize the electromagnetic field and to make comparisons with the professional human exposure limits.

In this paper the micrometric spiral inductors will be numerically modelled and simulated in order to highlight the effects and phenomena which occur at high frequencies, namely in the frequency domain 1 – 20 GHz. At first the electric and magnetic field values inside the structure of the spiral inductor are represented and analyzed. Also, the specific parameters of these spiral inductors, namely the inductance L, the scattering parameters S and the quality factor Q are determined with the help of the ANSYS-HFSS program and their values are analyzed in order to identify and highlight the effects which arise considering the variation of some geometrical parameters of these spiral inductors.