Modeling of an EMC test-bench for conducted emissions in solid state applications

In the area of EMC performance of electric motor drives, research is mainly focused on the EMC performance of inverter based drives. However, in most instances the soft starter is still an appropriate choice for motor control especially when accurate speed control of the load is not a specific requirement. The EMI generation of these converters has not been given the required importance, with only a few publications regarding this issue available in the last decades. A simulation model that considers the operation of solid state devices in an EMC conducted emission measurement laboratory environment was developed. The model was implemented in MATLAB® and Simulink® using a time domain approach. Models for the LISN, EMI receiver, power cables, thyristor power modules and induction motor load were developed and implemented. These models were developed so as to reflect the actual physics of the components and, where possible, model parameters were obtained through analysis of the geometry of the system through simplifications of the surrounding environment. The simulation was then used to gain insight on the EMI generation mechanisms of the solid state system.non peer-reviewe

A physical model for low-frequency electromagnetic induction in the near field based on direct interaction between transmitter and receiver electrons

A physical model of electromagnetic induction is developed which relates directly the forces between electrons in the transmitter and receiver windings of concentric coaxial finite coils in the near-field region. By applying the principle of superposition, the contributions from accelerating electrons in successive current loops are summed, allowing the peak-induced voltage in the receiver to be accurately predicted. Results show good agreement between theory and experiment for various receivers of different radii up to five times that of the transmitter. The limitations of the linear theory of electromagnetic induction are discussed in terms of the non-uniform current distribution caused by the skin effect. In particular, the explanation in terms of electromagnetic energy and Poynting’s theorem is contrasted with a more direct explanation based on variable filament induction across the conductor cross section. As the direct physical model developed herein deals only with forces between discrete current elements, it can be readily adapted to suit different coil geometries and is widely applicable in various fields of research such as near-field communications, antenna design, wireless power transfer, sensor applications and beyond

Remote power delivery for hybrid integrated Bio-implantable Electrical Stimulation System

Bio-implantable devices such as heart pacers, gastric pacers and drug-delivery systems require power for carrying out their intended functions. These devices are usually powered through a battery implanted with the system or are wired to an external power source. In this work, a remote power delivery system (RPDS) is considered as a means to charge rechargeable batteries that power a Bio-implanted Electrical Stimulation System (BESS). A loosely coupled inductive power transmitter and receiver system has been designed to recharge batteries for a bio-implanted gastric pacer. The transmitter coil is periodically worn around the waist. The receiver coil, rechargeable batteries, battery-charging chip and the chip containing electrical stimulation circuitry form a bio-implanted hybrid integrated microsystem. The link efficiency between a transmitter coil and the implanted receiver coil when the diameters are markedly different is analyzed. A design methodology for RPDS is proposed based on the load and voltage required at the load. An analytical model is developed with the help of simple Matlab coding. A full wave rectifier with a voltage doubler circuit is used for the conversion of ac voltage to the required dc voltage. This dc voltage supplies power to a battery charging chip which is used to safely and appropriately charge a rechargeable Li-ion battery. For an input supply voltage of 17.67 V rms, operating frequency of 20 kHz and radial coplanar displacement between the coil axes of 7.5 inches, the maximum dc voltage and power obtained across a 65Ω load resistor are 9.65 V and 1.33 W respectively. For a radial coplanar displacement between the coil axes of 6 inches, a 3.7 V nominal, 150 mAh polymer lithium ion battery has been successfully charged in 1 hour and 40 minutes from an initial voltage of 3.39 V to 4.12 V with an input voltage of 19.81 V rms at 20 kHz. An attempt has been made to model coil parasitics at high frequency. Variations in the load power as a function of frequency and radial coplanar displacement of the axes are examined. Design strategies to optimize power delivery with given geometric constraints are considered

Model order reduction techniques for PEEC modeling of RF & high-speed multi-layer circuits.

by Hu Hai.Thesis (M.Phil.)--Chinese University of Hong Kong, 2006.Includes bibliographical references.Abstracts in English and Chinese.Author's Declaration --- p.iiAbstract --- p.iiiAcknowledgements --- p.viTable of Contents --- p.viiiList of Figures --- p.xiList of Tables --- p.xivChapter Chapter 1 --- Introduction --- p.1Chapter 1.1 --- Background --- p.1Chapter 1.2 --- Overview of This Work --- p.2Chapter 1.3 --- Original Contributions in the Thesis --- p.3Chapter 1.4 --- Thesis Organization --- p.4Chapter Chapter 2 --- PEEC Modeling Background --- p.5Chapter 2.1 --- Introduction --- p.5Chapter 2.2 --- PEEC Principles --- p.6Chapter 2.3 --- Meshing Scheme --- p.10Chapter 2.4 --- Formulae for Calculating the Partial Elements --- p.12Chapter 2.4.1 --- Partial Inductance --- p.12Chapter 2.4.2 --- Partial Capacitance --- p.14Chapter 2.5 --- PEEC Application Example --- p.15Chapter 2.6 --- Summary --- p.17References --- p.18Chapter Chapter 3 --- Mathematical Model Order Reduction --- p.20Chapter 3.1 --- Introduction --- p.20Chapter 3.2 --- Modified Nodal Analysis --- p.21Chapter 3.2.1 --- Standard Nodal Analysis Method Review --- p.22Chapter 3.2.2 --- General Theory of Modified Nodal Analysis --- p.23Chapter 3.2.3 --- Calculate the System Poles Using MNA --- p.27Chapter 3.2.4 --- Examples and Comparisons --- p.28Chapter 3.3 --- Krylov Subspace MOR Method --- p.30Chapter 3.4 --- Examples of Krylov Subspace MOR --- p.32Chapter 3.5 --- Summary --- p.34References --- p.35Chapter Chapter 4 --- Physical Model Order Reduction --- p.38Chapter 4.1 --- Introduction --- p.38Chapter 4.2 --- Gaussian Elimination Method --- p.39Chapter 4.3 --- A Lossy PEEC Circuit Model --- p.44Chapter 4.3.1 --- Loss with Capacitance --- p.44Chapter 4.3.2 --- Loss with Inductance --- p.46Chapter 4.4 --- Conversion of Mutual Inductive Couplings --- p.47Chapter 4.5 --- Model Order Reduction Schemes --- p.50Chapter 4.5.1 --- Taylor Expansion Based MOR Scheme (Type I) --- p.51Chapter 4.5.2 --- Derived Complex-valued MOR Scheme (Type II) --- p.65Chapter 4.6 --- Summary --- p.88References --- p.88Chapter Chapter 5 --- Concluding Remarks --- p.92Chapter 5.1 --- Conclusion --- p.92Chapter 5.2 --- Future Improvement --- p.93Author's Publication --- p.9

Wireless Power Transfer

Wireless power transfer techniques have been gaining researchers' and industry attention due to the increasing number of battery-powered devices, such as mobile computers, mobile phones, smart devices, intelligent sensors, mainly as a way to replace the standard cable charging, but also for powering battery-less equipment. The storage capacity of batteries is an extremely important element of how a device can be used. If we talk about battery-powered electronic equipment, the autonomy is one factor that may be essential in choosing a device or another, making the solution of remote powering very attractive. A distinction has to be made between the two forms of wireless power transmission, as seen in terms of how the transmitted energy is used at the receiving point: - Transmission of information or data, when it is essential for an amount of energy to reach the receiver to restore the transmitted information; - Transmission of electric energy in the form of electromagnetic field, when the energy transfer efficiency is essential, the power being used to energize the receiving equipment. The second form of energy transfer is the subject of this book

Modeling and analysis of thick suspended deep x-ray liga inductors on CMOS/BiCMOS substrate

Modeling and simulation results for two types of 150 μm height air suspended inductors proposed for LIGA fabrication are presented. The inductor substrates used model the TSMC 0.18 μm CMOS/BiCMOS substrates. The RF performance between the suspended structure and the unsuspended counterpart are compared and the advantage of the suspended structures is explored. The potential of LIGA for fabricating high suspended inductors with good performance and for combining these with CMOS/BiCMOS is demonstrated

Enhancement of Inductive Power Transfer Technology: Iron-based Nanocrystalline Ribbon Cores

Inductive power transfer (IPT) has been studied extensively during the last decades, particularly for electric vehicle chargers (EV). Inductive chargers offer several advantages over standard plug-in ones. First, they reduce user interaction increasing comfort and mitigating safety concerns. Furthermore, they allow for the automation of the charging process and the implementation of opportunity charging schemes. Thus, distributed charging points can be deployed in strategic locations — such as traffic lights, public and private parking places, etc.— and EVs can be charged more frequently. This reduces the depth of discharge of the battery and increases its lifespan. Furthermore, IPT systems with bidirectional power flow can facilitate the adoption of vehicle-to-grid schemes (V2G). IPT technology is reaching a mature state. Nevertheless, several aspects of the technology can still be improved. First, the state-of-the-art systems are sensitive to misalignments between the transmitter and receiver pads. Second, the complete standardization of the pad's design has not yet been achieved. Consequently, the interoperability of systems designed by different manufacturers is not yet guaranteed. Third, the detection of foreign objects between the pads is a problem that has not been completely solved. Last, the power density of the pads can still be improved. Pads are generally large and heavy which hinders the adoption of this technology. This dissertation addresses some of these problems in an attempt to enhance the state-of-the-art of IPT technology. The largest portion of this thesis is dedicated to the study of alternative core materials for IPT charging pads. In particular, nanocrystalline ribbon cores are considered a promising material. This material offers a higher saturation flux density, a higher permeability, superior thermal performance, and mechanical robustness compared to the standard MnZn ferrites commonly used in IPT systems. A feasibility analysis of this material was carried using intricate finite element models and experimental measurements. The analysis concluded that higher power densities can be effectively achieved with nanocrystalline ribbon cores. However, eddy-current losses on the outer/lateral faces of the cores were identified as problematic. This motivated a new design approach in which the unique properties of this material were considered during the design stage. Guidelines for the design of nanocrystalline ribbon cores were derived. These were applied to the design of a WPT3, 11 kW pad. These pads showed superior performance as compared to identical pads with ferrite cores. Pads with nanocrystalline cores were 2% more efficient and achieved an 11% higher coupling factor. Likewise, up to 25%, lower flux leakage was obtained. Moreover, their performance concerning temperature variation outperformed the one from ferrite cores both in heat dissipation and thermal stability. Finally, the pads were tested near magnetic saturation. Nanocrystalline cores were able to transfer more power before reaching this point. Thus, higher power densities were achieved with this material. Finally, methods for reducing the eddy-current losses in the system were tested. Ferrite shielding, in particular, was found to be an effective method to improve efficiency and homogenize the temperature distribution within the core. As a minor contribution, a control strategy that uses the dual-resonant frequency characteristic of LCCL-compensated pads is also presented. This strategy was validated experimentally, and it can be used to increase the power transfer capability of pads under misaligned conditions. Moreover, this strategy can ease the interoperability of IPT pads designed by different makers which have different ratings and dimensions

Analysis, design, and optimization of antennas on CMOS integrated circuits for energy harvesting applications

Radio frequency (RF) energy harvesting is a promising technology that finds applications in such products as Radio Frequency Identification (RFID) and Active Remote Sensing (ARS). In order to reduce the overall size and the manufacturing cost of the device, it is highly desirable to integrate the energy-harvesting antenna, onto the same monolithic CMOS integrated circuit as the functional circuitry. The focus of this dissertation is on the extension of the more traditional approach to antenna design while overcoming the many barriers to the design and analysis of tiny antennas that are fabricated on a CMOS die resulting in an extremely unfriendly environment. Specifically, the major challenges for building antennas on CMOS ICs have been identified. The Finite Element Method (FEM) was found to be the most suitable numerical method for the full-wave analyses of antennas on CMOS ICs after a comparison of the major numerical methods available for electromagnetic simulations. A complete power measurement system that requires no cable connection to the antenna under test has been constructed. It offers accurate measurement of the available power from the on-chip antennas with the help of the annealing approach to impedance matching, which was also developed in this research. The various design factors for antennas on CMOS ICs have been evaluated through both simulation and experiments. It was concluded that the properly designed spiral antennas are good candidates for the on-chip energy-harvesting applications

System identification for black-box macro-modeling with Loewner matrix framework

Macro-modeling is important to protect intellectual property (IP) for manufacturers. With the current and growing complexity of modern electronics circuitry, algorithms that enable accurate and fast simulation are desirable. Vector fitting has been used in the industry for years for black-box macromodeling. Loewner matrix is newly introduced and appears to be a promisingalgorithm by its capability of handling systems with many ports. This work provides details about the Loewner matrix framework and its current development. Specifically, preparations of interpolation data for calculating Loewner matrices, and how to find the optimal order for the reducedorder model are discussed. Many numerical examples with measurement data will also be provided