Source reconstruction in near field scanning for RFI application

This research is divided into three major topics. The first topic, mechanical magnetic field generator for communication in the ULF range, is discussed in the first paper. The second topic, source reconstruction in near field scanning for RFI application, is discussed over the course of two papers. The third topic, analysis of imbalanced 2 or 3 Wire VHF LISN, is discussed in the last two papers. In the first topic, the possibility to use a mechanical system (a rotating magnet) as a source (generator or antenna combined) of the ULF magnetic field is investigated. Ultralow frequency (ULF) communication systems have advantage over the RF systems in lossy media such as soil or water. A conventional way to create ULF fields is to use coils. It is demonstrated that the mechanical sources have advantage over coils in terms of occupied volume or dissipated power and can be a viable alternative for low-size, weight, and power applications. In the second topic, methods are presented to predict the high-frequency near electric- and magnetic- fields from a component using a Method of Moment (MoM) approach. Additionally, the impact of three major sources of error in near field scans: random measurement noise, cross field coupling, and position error, is investigated on field prediction. A clear decision-making process with examples is provided to guide the user toward selection of the best representation. In the third topic, an analysis of an imbalanced two- or three-wire VHF LISN is conducted in terms of its mode conversion and termination impedance. It is demonstrated that an imbalanced termination impedance provides a specified degree of conversion from differential- to common-mode, which can lead to more representative radiated emission test results --Abstract, page iv

Construcción de una cámara semianecoica para test de componentes de automoción

En este trabajo fin de máster se presenta una solución al problema de la construcción de una cámara semianecoica para componentes de automoción, tratando de plasmar los requerimientos necesarios para construirla, un método para validarla y finalmente su puesta en marcha. Es un proyecto de ingeniería que se llevó a cabo entre 2017 y 2018 en la empresa Applus Laboratories, situada en Bellaterra (Barcelona).In this proyect, a solution is presented when building a semi-anechoic chamber for automotive components, trying to show the necessary requirements to build it, a method to validate it and finally its start-up. It was an engineering project that was carried out between 2017 and 2018 in the company Applus Laboratories, located in Bellaterra (Barcelona).Universidad de Sevilla. Máster Universitario en Electrónica, Tratamiento de Señal y Comunicacione

EMC Performance Evaluation of Various PCB Designs through Simulation and Measurements

The applied research presented in this thesis is intended to deepen the understanding of various concepts related to PCB design with respect to EMC and RF performance. The first topic addressed is embedded capacitance of a PCB. The work includes decoupling capacitors and their placement relative to the IC in a combination of three different PCB stack-ups. The evaluation is performed in the frequency domain and time domain. The next topic discussed is the EMC/ EMI filters which are essential measurements to protect a device or subsystem from EMI. The circuit\u27s load is usually unknown. A generic filter design is built, which allows the placement of various PCB structures to evaluate filters under different load and source impedance. To convert voltage effciently, SMPS buck converters are widely used. To suppress EMI, various counter measures for differential mode, and common mode are discussed and measured with a conducted emission (CE) voltage method (V) to evaluate their performance. The designed snubber is evaluated in the time domain by measuring the ringing and the suppressed target frequency content. The results of the above four topics are utilized in a VHF auto tuner design. The results of the embedded capacitance frequency domain evaluation show that the two evaluated 6-layer designs outperform the 4-layer design. Additionally, the 6-layer design with far spaced power plane outperforms the 6-layer version 3 design with not-far spaced power plane referenced to the top signal layer. Grouped capacitors outperform the not grouped capacitors. For not grouped capacitors on a 6-layer design, the evaluation in time and frequency domain shows that the 6-layer designs are particularly enhancing higher frequency content suppression regardless if the capacitors are grouped or not. The filter evaluation showed that for a 2nd order filter the capacitor placed close to the high impedance side shows increased performance. The 3rd order structures π and T show that there is no significant performance decrease if the filter is mounted one way or another. The correlation of the measured and simulated data showed that the ideal case simulations are valid for the ideal behavior of the filter. Due to the bandwidth of a π filter, large components with lower self-resonance frequencies are favorable. In real-world applications, a π is favorable because there never is just an LC or CL structure due to bulk or decoupling capacitors. The SMPS evaluation showed that the snubber could be designed with Adamczyk\u27s and Spence\u27s approach. The tested EMC filter structures showed clearly that a single component shows an impact on the CE (V) measurement and can be identified by its self-resonant frequency. The filter can be designed for different target frequency ranges, and depending on the design, it will show better or worse results. The shield was added, and the measured interference dropped mainly to the ambient level. On the VHF auto tuner each evaluated topic is discussed and shows that around 50% of the used components are related to EMC. The presented work illustrates the multidisciplinary character of electromagnetic compatibility (EMC)

Contribution to improve the EMI performance of electrical drive systems in vehicles with special consideration of power semiconductor modules

Diese Arbeit dient als Beitrag zur Verbesserung des EMV-Verhaltens elektrischer Antriebssysteme in Fahrzeugen, wobei der Fokus auf dem Leistungshalbleitermodul für die Automobilanwendung liegt. Für ein besseres und tieferes Verständnis der Quelle von leitungsgebundenen Störungen werden die EMV-Mechanismen und -Effekte im Zusammenhang mit dem Leistungsmodul im Antriebssystem durch Simulationen und Messungen untersucht. Der Einfluss der Diode Reverse Recovery Effekte auf das EMV-Verhalten wird quantitativ mit verschiedenen Lastströmen sowie mit verschiedenen Diodentypen, wie z.B. SiC-Schottky-Dioden, analysiert. Durch Simulationen wird der Einfluss des Leistungsmoduls auf das System untersucht; auf dieser Basis wird die Bedeutung verschiedener Faktoren innerhalb und außerhalb des Leistungsmoduls für das EMV-Verhalten bewertet. Zur Validierung der Simulationsergebnisse wird der Messaufbau für eine konventionelle EMV-Messung für die Automobilanwendung vorgestellt. Die Messergebnisse belegen, dass die Simulationsmodelle unter bestimmten Randbedingungen für zukünftige Leistungsmodulkonstruktionen zur EMV-Vorhersage verwendbar sind. Basierend auf dem Verständnis, wie es aus den Simulationen und Messergebnissen hergeleitet wurde, werden konkrete Optimierungskonzepte für ein inhärent störungsarmes Leistungsmodul entwickelt und realisiert. Dessen EMV-Verhalten sowie der Aufwand des Musterbaus aus Sicht des Leistungsmodulherstellers werden anhand verschiedenen Kriterien verglichen und bewertet. Außerdem wird das dynamische und Kurzschlussverhalten der Prototypen einschließlich der Stromverteilung zwischen den Halbleiterchips charakterisiert. In dieser Arbeit wird ein neuartiges Testverfahren vorgestellt, mit dem es möglich ist, das leitungsgebundene EMV-Verhalten von Leistungsmodulen abzuschätzen, ohne den gesamten Testaufbau wie bei einer konventionellen EMV-Messung zu erstellen. Diese Charakterisierung kann anschließend in der Phase der Inverterentwicklung verwendet werden, um ein geeignetes Modul auszuwählen und den erwarteten Aufwand zur Einhaltung der EMV Standards zu bewerten.This work serves as a contribution to improve the EMI performance of electrical drive systems in vehicles; the focus is on the power semiconductor module for automotive application. For a better and deeper understanding of the conducted EMI source, the conducted EMI mechanisms and effects in the drive system are investigated through simulations as well as measurements with special consideration of power modules: The influence of the diode recovery effects on the EMI performance is quantitatively analyzed with different load currents, as well as with different types of diodes, e.g. SiC Schottky barrier diode. Through the simulation, the influence coming from the power module to the system is clarified; the importance of different factors inside and outside of the power module regarding EMI performance are therefore evaluated. To validate the simulation results, the setup and test bench for a conventional EMI measurement for the typical automotive application are presented. Through the measurement results it is proven that the simulation models are usable under certain boundary conditions for future power module designs with regard to the EMI prediction. Based on the understanding and the conclusions from the simulation and measurement results, concrete EMI optimization concepts for an inherently low-interference power module are developed and realized. The EMI performance as well as the feasibility of the sample modules are compared and evaluated under different criteria from the power module manufacturer’s point of view. Besides, the dynamic and short-circuit performances of the sample modules, regarding to the current distribution on the semiconductor chips, are characterized. A novel test procedure is introduced in this work, by which it is possible to estimate the conducted EMI performance of power modules without building the whole test setup like in a conventional EMI measurement. This characterization can subsequently be used in the phase of converter development to select a suitable device and evaluate the expected effort to comply with EMI standards

Recent Topics in Electromagnetic Compatibility

Recent Topics in Electromagnetic Compatability discusses several topics in electromagnetic compatibility (EMC) and electromagnetic interference (EMI), including measurements, shielding, emission, interference, biomedical devices, and numerical modeling. Over five sections, chapters address the electromagnetic spectrum of corona discharge, life cycle assessment of flexible electromagnetic shields, EMC requirements for implantable medical devices, analysis and design of absorbers for EMC applications, artificial surfaces, and media for EMC and EMI shielding, and much more

Gateway Requirements for the Control of Electromagnetic Interference Characteristics of Subsystems and Equipment

This document is a tailored version of MIL-STD-461, Requirements for the Control of Electromagnetic Interference Characteristics of Subsystems and Equipment, for the Gateway Program. While many of the requirements contained herein correspond with a MIL-STD-461 requirement, some are unique to the Gateway Program in order to meet the specific needs of the program. Nearly all limits are tailored specifically for Gateway elements, systems, and subsystems

Performance Evaluation of Powerline Technology on Low Voltage Distribution Networks

Powerline technology (PLT) employs the electrical distribution network to transmit data in addition to supplying power. PLT is currently employed to provide data networking in many domestic environments, and is expected to play a major part in the development of the forthcoming Smart Grid. Given that the electrical distribution network was not designed with data transmission in mind, electromagnetic radiation from the network can give rise to interference. Regulators and researchers have considered the impact of such widespread radiation, and investigations of the various aspects of powerline have been conducted over the last decade. Despite this prolonged period, however, there remains a lack of agreement on the typical performance of such networks or the implications for regulation policy. An accurate model of the radio frequency (RF) properties of the typical electrical distribution network would be extremely valuable in developing standards and informing policy. The aim of this thesis is to provide a cohesive approach to determining the RF characteristics of a typical domestic property and applying such parameters to model the performance of PLT. The thesis reviews the recent development of broadband PLT, the progress made by the more prominent regulators, and the trials undertaken to define the key parameters affecting propagation. A detailed experimental programme carried out both in the laboratory and at typical sites is described. An empirical model of the RF performance of a UK domestic low voltage distribution network (LVDN) is developed from analysis of the experimental results. It is shown via this analysis that discrete measurements of the conducted and radiated parameters can be related and that the RF performance of the LVDN can be described by Conversion and Radiated Loss. The radiated field is shown to comprise the combined common mode current to the LVDN and common bonding network (CBN). The thesis concludes with consideration of the future development of powerline technology, particularly in support of the Smart Grid development

Electromagnetic Compatibility in Wireline Communications

This document is a thesis submitted in partial fulfilment of the requirements of the University of Hertfordshire for the degree of Doctor of Philosophy (Part Time) in 'EMC in Wire-line Communications' in the School of Electronic, Communication and Electrical Engineering at the University of Hertfordshire. It describes a programme of research into the modelling and measurement of radio frequency interference emissions from various communication networks including Power Line (Tele)communications (PLC/PLT) and Digital Subscriber Line (DSL). An introduction and literature review are followed by the results of practical measurements on installed networks. These measurements include antenna gain and Longitudinal Conversion Loss (LCL). Power line communication networks, splitterless DSL and home phoneline networks in buildings are studied and modelled and the models are compared with the measured results. Improved EMC test methods are also described, in particular the modelling and design of four types of portable antennas for use in radiated EMC measurements with improved sensitivity at frequencies up to 30 MHz. The first type is a set of three manually tuned loop antennas covering 100 kHz - 30 MHz. The second is a set of three loop antennas that cover a similar frequency range but with remote tuning via an optical fibre link, under the control of software which also controls an EMC measuring receiver. The third type is a larger (1.6 m diameter) tuned loop covering 1.75 - 10 MHz that allows the measuring system noise floor to be below the typical atmospheric noise floor. The fourth type is an electrically short dipole covering 10 - 30 MHz with improved matching. The protection requirements for various types of radio communication services are analysed and are compared with emission levels from various types of wireline communication network. A review of existing applicable EMC standards and standards under development is also presented

Radiated Emissions From High Frequency Powerline Telecommunications (PLT) Systems

The use of broadband Powerline Telecommunications (PLT) to deliver high speed services has been anticipated since the late 1990s. Due to its radiated emissions in the High Frequency (HF) band, the regulatory authorities have had difficulty in defining a repeatable measurement technique and an acceptable radiated limit for Electromagnetic Compatibility (EMC) compliance. Other researchers have undertaken work to predict, model or measure the effects on victim receivers but the uncertainty of the measurements is rarely discussed. This thesis identifies the areas of uncertainty in PLT radiated emission measurements and recommends a method to account for the measurement errors. A measurement campaign was undertaken in urban, rural and semi-rural test sites in the UK to demonstrate the effects of antenna type, orientation and measurement distance. Furthermore for each measurement location, attenuation with distance properties are described which can be used in the prediction of PLT radiated emissions at a distance. Additionally the K-factor which had previously been thought to be a useful parameter is calculated at each location and is shown to be of little value in the determination of a “safe radiated emission limit” for PLT. A novel test method of mutual interference testing is described which provides a more realistic demonstration of the effects of PLT radiated emissions on HF receivers. In conjunction with a risk mitigation strategy a compromise radiated emission limit is recommended that may facilitate the regulation of PLT

전기적으로 빠른 과도현상/버스트 복사 잡음에 관한 대책 연구

Civilization using electromagnetic wave has a lot of advantages which is completely changing the life pattern of the mankind. However, Malfunction by various interference between electric equipments and hazards on health have become serious problems. Thus, Regulation of electromagnetic waves have been increasingly tighten up in most of the world, including Republic of Korea. Most of the major countries have administered certified international laboratory under the ILAC in order to solve problems such as trade barriers from electric equipment which is not satisfied regulation of electromagnetic waves. In Korea, KOLAS has made mutual recognition arrangements with the ILAC and laboratories accredited KOLAS have improved the reliability and repeatability of measurement through an accurate analysis of international standards. In this dissertation, problems about EFT/Burst test, referenced in the IEC-61000-4-4 of the international standard related to verifying EMC of electric equipments, was analyzed and measuring reliability was studied. As a result, the improved EFT/Burst immunity test method which considering the radiated EFT/Burst signals has been proposed. Firstly, the test sample was set up by the standard regulation and then the +4 kV EFT/Burst signal was generated by 1 m long power cable for 1 minute. Consequently, it was found that not only induced EFT/Burst signal along power line of EUT, but also directly radiated emission signal from the EFT/Burst signal generator. The radiated emission signals was 30dB higher than limit of CISPR 22 which is international EMC standard. Moreover, the electric field strengths were measured by changing the distance from the point with the maximum radiated emission to the electric field strength tester. As a result, this electric field strength was 23 V/m which is higher than international EMC standard test level (CISPR 24). Therefore, it was confirmed that the probability of malfunction may be high when radiated emission of EFT/Burst noise exists near the EUT. Then, reliability of measurement results of IEC61000-4-4 standard was discussed through the field strength measurement according to the separated distances of the receiver to the maximum source of the radiated EFT/Burst signals, the analysis of the influence from the power line type and length, the analysis depends on the type of the test sample, and the studies of suppression effect from the radiated EFT/Burst signals. Consequently, the radiated EFT/Burst signals directly cause malfunction of EUT, and it was confirmed that malfunctions of EUT can be solved by applying countermeasure method of radiated noise. In addition, it was proposed that countermeasure method from EFT/Burst signals should be considered not only for conductive noise but also for the radiated noise. Furthermore, reliable arrangement of EFT/Burst immunity test were searched according to the structure of the EUT’s enclosure, materials, and operating environment. In this dissertation, the improved EFT/Burst immunity test method which considering the radiated EFT/Burst signals has been proposed.Nomenclature Abbreviations Abstract 제1장 서 론 1 1.1 연구 배경 및 목적 1 1.2 연구 방법 3 제2장 전자파 내성 신호에 관한 이론 및 시험 5 2.1 전자파적합성 5 2.1.1 EMC 개요 6 2.1.2 EMC를 고려한 설계법 8 2.1.3 EMC 규제 규격 9 2.2 대표적인 EMC 시험의 종류 및 시험 방법 16 2.2.1 복사성 방사시험 17 2.2.2 전도성 방사시험 19 2.2.3 잡음 전력시험 22 2.2.4 방사 내성시험 25 2.2.5 전도 내성시험 28 2.2.6 정전기 방전 내성시험 30 2.2.7 전기적으로 빠른 과도현상/버스트 내성시험 32 2.2.8 서지 내성시험 32 2.2.9 전압강하, 순시정전 및 전압변동 내성시험 35 제3장 EFT/Burst 내성 시험 및 방사성 잡음의 발생 38 3.1 전기적으로 빠른 과도현상/버스트 내성 시험 38 3.1.1 시험 목적 38 3.1.2 전기적으로 빠른 과도현상/버스트 신호 38 3.1.3 시험 환경 및 셋업 41 3.1.4 시험 인가 레벨 43 3.1.5 시험 절차 및 평가 44 3.2 EFT/Burst 복사 잡음의 발생원인 분석 45 3.2.1 전도성 신호의 전달경로 45 3.2.2 전도성 신호의 방사특성 48 3.2.3 신호 방사와 관련된 안테나 이론 50 3.2.4 전기적으로 빠른 과도현상/버스트 신호의 방사특성 55 제4장 EFT/Burst 복사 잡음의 측정 및 시험품의 영향도 분석 59 4.1 EFT/Burst 복사 잡음의 발생원 탐구 및 검증 59 4.1.1 근접프로브를 이용한 EFT/Burst 복사 잡음의 발생원 탐구 59 4.1.2 필드프로브를 이용한 EFT/Burst 복사 잡음의 발생원 검증 63 4.2 EFT/Burst 복사 잡음의 측정 65 4.2.1 공인시험법에 의한 EFT/Burst 복사 잡음의 측정 65 4.2.2 방사 내성 시험의 국제 규격치와 EFT/Burst 복사 잡음의 비교 69 4.3 다양한 시험 조건에서의 EFT/Burst 복사 잡음의 영향도 분석 71 4.3.1 이격 거리에 따른 전계강도 측정 71 4.3.2 시험품 전원선의 종류 및 길이에 따른 영향 77 4.3.3 시험품 종류에 따른 전계강도 측정 79 4.3.4 EFT/Burst 복사 잡음의 억제 효과 82 제5장 EFT/Burst 내성신호의 대책 방안 및 시험 방법의 제안 86 5.1 복사 잡음을 고려한 시험품의 EFT/Burst 내성 대책 방안 86 5.1.1 일반적인 EFT/Burst 내성신호 대한 대책 방안 86 5.1.2 EFT/Burst 복사 잡음에 의한 시험품의 오동작 및 대책 90 5.2 EFT/Burst 복사 잡음 억제를 위한 시험 시스템의 제안 97 5.2.1 EFT/Burst 내성시험 시스템 구성을 위한 환경 고찰 97 5.2.2 시험 대상 및 운용 환경에 따른 내성시험 시스템의 제안 199 제6장 결론 101 참고문헌 103 본 연구와 관련된 논문 실적 10