Electromagnetic Compatibility Design of Reinforced LCD

The Liquid Crystal Display (LCD) module in a high power TEA CO2 laser is easy to couple with electromagnetic interference, so as to affect the normal work of the laser. Therefore, this paper explores the prediction method of Electromagnetic Compatibility (EMC) for the LCD module under transient irradiation in an electromagnetic field. The coupling mechanism of electromagnetic interference received by the LCD module integrated in the laser system was analyzed. On the basis of the coupling of field and line, the field line electromagnetic interference of the LCD module was analyzed and calculated by using the BLT equation in the Taylor form, then, the prediction results were verified by several experimentally. The experimental results show that the interference voltage produced by connect cables coupled with electromagnetic fields on the data lines of LCD display module is 1 V, and exceeds the noise margin of the circuit. So the EMC control measures must be taken to ensure the performance of the LCD module. Moreover, the verification experiments indicate that prediction results for the EMC has correctly reflected the actual EMC performance of LCD module. The method has a guiding significance for prediction and design of EMC of electrical equipment in high-power TEA CO2 lasers.

The paper deals with the electromagnetic compatible design of medical products, starting from the early stage of the design process (the prototype stage). This way of thinking is presented for the case of one kinetic therapy equipment. In the functional block diagram of the equipment are pointed out the main electromagnetic interference paths. The specific test setup and measurements in accordance with the European conducted immunity standards for electromagnetic compatibility are presented. Two kinds of measurement were performed: inter-system measurements (to the mains supply port) and intra-system measurements (to the printed circuit board and the internal cables). Several solutions for mitigating electromagnetic interference problems which greatly improved the electromagnetic immunity of the equipment are also depicted. The main conclusion which must be drawn from the present paper is that designing for electromagnetic compatibility is the most energy saving and cost effective policy.

This paper deals with energy/power quality issues, correlated with Electromagnetic Compatibility (EMC) and electromagnetic interferences (EMI) which appear at urban transportation systems. One presents, briefly, some aspects regarding powers definitions for harmonic and/or unsymmetrical regimes from three-phase circuits, applicable to loads supplied from the a.c. line through low voltage power transformers and uncontrolled three-phase rectifiers. It is analysed the case of a driving system with d.c. motor and chopper, supplied from the d.c. line, which induces a significant non-sinusoidal regime in the a.c. network. The cases in which the load is not compensated, respectively compensated through an active filter are also analyzed through tests on stand. Aspects regarding powers and power flows for both cases are also discussed. Furthermore, the obtained data are compared using the quality standards IEEE 519/1992 and 1459/2000. One discusses the obeying of quality standards and some aspects, which are not approached in the specialty literature, concerning the corresponding EMC and EMI issues. Problems related to the tested driving system connection to the supplying system from the power substation for an urban transportation system are briefly presented. The waveforms of currents through the active filter are depicted. Some conclusions on approaching EMC and EMI at low frequencies, with an extension over 2 kHz and the relation with the IEC 61000-4-30 standard are also presented. It is underlined the necessity of treating energy/power quality issues in correlation with issues regarding EMC and EMI at low frequency for this type of loads.

The system level consideration of electromagnetic environmental effects (E3) in aircraft is one of the major concerns to aviation industry. Discussion of hazardous electromagnetic environmental effects in aircraft systems includes lightning, high intensity radiated fields (HIRF), precipitation-static (P-static), portable electronic devices (PEDs), and electromagnetic compatibility (EMC) issues. The electromagnetic environmental effects on aircraft have been exacerbated in recent years due to modern aircraft's increasing dependence on electronic devices for communication, navigation and flight control, and growing use of composite materials for airframe. In this paper, we review electromagnetic environmental effects in aircraft from a systems engineering perspective. Considering the complex, interrelated, and dynamic nature of electromagnetic phenomenon in aircraft, we find the systems engineering application to electromagnetic effects discussion appropriate and beneficial. In particular, we judge that risk analysis methodology is an underutilized but well-suited tool for understanding and mitigation of electromagnetic hazardous effects in aircraft systems. Herein we first introduce the Standard Risk Model (SRM), and then apply the model to electromagnetic risk events and impacts, and follow through with illustrative prioritized identifications. We next develop drivers for each risk event and impact, and finally we present the baseline risk prevention plans and associated impact contingency plans. We conclude with a summary of our findings and present future work suggestions for systems engineering application to aircraft electromagnetic environmental study and mitigation of the hazardous effects.

The electron cyclotron resonance heating (ECRH) is a very important plasma heating method in experimental advanced superconducting tokamak (EAST). There are four gyrotrons in the EAST ECRH system that can generate 4-MW/100-s/0.14-THz wave. The ECRH system is a complex terahertz system that involves ultralow temperature, ultrahigh vacuum, strong magnetic field, high-power electromagnetic wave, and weak diagnostic signal. There are many electromagnetic compatibility problems in the ECRH system. This is the first report about the electromagnetic compatibility for the ECRH system. In the operation of the ECRH system, many electromagnetic compatibility problems have been found and resolved. We can suppress the interference and improve the accuracy of power monitoring and the effectiveness of radio frequency protection by using the magnetic rings. The influence of the magnetic field on the current transformers was analyzed. Some electromagnetic compatibility issues in the data acquisition system were discussed. After solving the electromagnetic compatibility problems, the EAST ECRH system can stably output high-power terahertz wave.

Electromagnetic modeling is a critical analysis and design methodology in various fields such as radio‐frequency (RF) and microwave engineering, antennas, radar, remote sensing, medical diagnostics, bio‐electromagnetics, physics and radio astronomy, and electromagnetic compatibility (EMC) and interference. It formulates and solves electromagnetic field problems using mathematical, physical, or computational models that relate the electromagnetic functionality of devices to their geometrical and material parameters or predict how electromagnetic fields interact with physical objects and materials. This chapter presents the most common methods for modeling electromagnetic scenarios in the frequency, the spectral, and the time domain, as well as their hybrid combinations. They are introduced as projective approximations of field solutions using the method of weighted residuals (MWR). This unified perspective best illustrates their properties, differences, and their suitability for solving a particular electromagnetic problem, thus helping the reader to appreciate the connections, similarities, and differences among the various methods. It also reflects historical and methodological developments and aims to provide a foundational understanding of current electromagnetic modeling methods.

In the process of high-efficiency control of aircraft, power electronic equipment brings a series of electromagnetic interference problems due to its own electromagnetic characteristics, which makes the electromagnetic environment on the aircraft carrier become worse. Therefore, it must take measures to control the electromagnetic interference. In this paper, the mechanism of electromagnetic interference generation of airborne power electronic equipment is analyzed. And some electromagnetic interference control techniques are proposed from the aspects of anti-interference design and electromagnetic compatibility test which can provide technical guidance for electromagnetic compatibility design and testing of airborne power electronic equipment.

A high performance mobile shielded shelter was designed and developed by CVRDE, Ministry of Defence, (DRDO) Chennai for telemetry application in combat vehicles sub system health monitoring purpose. This paper dwells upon the basic shielding requirements of such shelters, design and construction aspects, utilities installed and shielding effectiveness tests carried out at LRDE EMI/EMC test facility. This shelter forms part of the project Vehicle Electronic Data Acquisition System (VEDAS) to simulate the Command and Control roles of combat vehicles which incidentally uses a number of communication sets in HF, VHF and UHF bands besides densely packed tank electronic sub system leading to interesting EMI/EMC challenges/solutions. The health data of all sub systems are displayed, analyzed and reported in the shelter for the convenience of decision-makers. The SE results achieved are reported in this paper, which are the best figures achieved so far in mobile shelters of double isolation construction techniques with MS as basic shielding material. The test results and photographic views of the shelters are included in this paper. The indigenous design efforts and details of fabrication work are also reported in this paper.

Due to the space limitation and safety concerns, the non-same-phase anti-parallel connection structure is applied in the ITER Poloidal Field (PF) converter unit. Consequently, the electromagnetic interference (EMI) has been one of the main concerns in its design. And this paper mainly presents the electromagnetic compatibility (EMC) analysis and design for ITER PF converter unit. At first, an isolated phase bus is designed for the shielding of the alternating magnetic field generated by the a.c. busbars. Its shielding effectiveness has been verified by the analysis and experimental test. Then, the stray magnetic field, which is generated by the converter bridges and very hard to be shielded, is analyzed and measured. And the results will provide useful inputs for the EMC design and test of the instrument and control (I&C) system. At last, a large coil pair, able to generate a uniform static magnetic field with high strength, is designed to evaluate the effects on electronic devices and to demonstrate the reliable and safe operation of the converters under strong stray magnetic field.

Unmanned Aircraft Systems may allow to y an uninhabited airplane or satellite with an autonomous control and monitored by the supervisor on ground. Safety y must be guarantee as the rest of airworthiness airplanes or space compliance satellites. The Unmanned Aircraft Systems were designed to operate in dangerous situations, like military missions bud nowadays, civil commercial applications come to be feasible due to the evolution in distributed embedded avionics systems. Dull and tedious surveillance applications are desired for this Unmanned Aerial Vehicles. A pico-satellite is a less than a kilogram mass satellite used mainly on educational projects for Low Earth Orbit (LEO) missions. Due to short time of live, down-link communications are implemented in a very high level of integration and non-gravity conditions in order to deliberate the scienti c information before drop down to the atmosphere. Both, Unmanned Aerial Vehicles and pico-satellites present same electromagnetic compatibility problems. This high level of integration, some times brings an electromagnetic interference situation between embedded systems especially because the near eld of emissions are present in the Unmanned Aircraft System reduced con ned avionics bay. Emission, Susceptibility, and Path are playing in this environment. That was our experience with an UAV Megastar model. The near earth antenna re ection produced a multi-path coupling. The radio transmitter antenna makes unserviceable the entire ight control surfaces, situation that makes an unsafe y. Also, during the pico-satellite design we must take in consideration the near eld for a good electromagnetic compatibility requirements. This paper is an electromagnetic compatibility study for Unmanned Aircraft System. We will show a case of real electromagnetic interference in our particular UAV Megastar, and how was solved. We will present some good EMC practices in order to translate the distributed embedded avionics platform to our new UAV Shadow MK1. Also we present our pico-satellite design and many examples of solutions of electromagnetic interferences. Finally we will consider an electromagnetic interference reduction check list applied on Unmanned Aircraft System where avionics bay con guration may change depending on the requirements of the mission.

With the development of high-speed network technology, ethernet chips play an increasingly important role in the field of vehicle electronics. However, the working frequency of ethernet chip is increasing, and the vehicle electronic environment it faces is becoming more and more complex, so the electromagnetic compatibility problem of vehicle ethernet chip is becoming more and more prominent. The electromagnetic reliability of vehicle ethernet chip is the foundation of the electromagnetic reliability of the system and even the whole vehicle. Based on the vehicle ethernet chip, this paper analyzes its electromagnetic compatibility, analyzes the current relevant standards, and explores the electromagnetic compatibility of the vehicle ethernet chip with the actual test case.

The paper is the result of studies, experiments and simulations regarding electromagnetic compatibility (EMC) performance of an intelligent electronic module used to obtain variable and controllable power injection during the Vapor Phase Soldering process (VPS) including the power-on and power-off phases. The module represents an original solution for low conducted and especially low radiated emissions by switching the power semiconductor devices close to the zero crossing of the mains voltage. The necessity to be optimized from EMC points of view is resolved by modeling and simulating using 3D EM simulation software, REMCOM XFdtd, for evaluating the performance and electromagnetic field effects of the VPS process power control module considered as a radiating device. The modeling process is based on preliminary measurements already taken and validated by other complex measurements which imply the need for the new experiments design. The authors intend to develop a design methodology based on the works presented in the paper which will include modeling and EM simulation, in order to complete the design for excellence (DFX) activities in case of the new products development processes.

The paper deals with solving electromagnetic compatibility (EMC) problems in the design of a new, case study, industrial high voltage test laboratory, intended to be used for testing of transformers and other apparatus up to 550 kV rated voltage. Modern high voltage test facilities are equipped, apart from primary test devices like AC, DC and impulse voltage generators etc., also with sophisticated numerical measuring instruments and informatics technology. Since such devices are sensitive to transient overvoltages, the highest degree of EMC is to be secured. This can be achieved by proper earthing and screening of test laboratory, what shall be designed in a way to satisfy all requirements conditioned by building lightning protection, personal protection and system earthing, avoiding electromagnetic compatibility disturbances at the same time. One of the main tasks is solving electromagnetic compatibility problems caused by outdoor electromagnetic disturbances originating from various unknown sources. Those disturbances and interferences may seriously influence measuring accuracy and readings of test devices, what consequently leads to false results. The stated is especially relating to partial discharge measurements. As to avoid such disturbances, the laboratory shall be completely screened with a net forming optimally designed Faraday cage. On the other hand, at high voltage tests with impulse voltages, especially with chopped tail waves, steep transient overvoltages may be generated. As a consequence, high transient potential differences between particular points along the earth electrode may occur, what can even lead to flashovers between parts of it. Therefore is of utmost importance to provide proper earthing and low inductance current return path for impulse high voltage test equipment where high frequency transients are to be anticipated. Improper earthing and bonding may result, apart from mentioned flashovers, in severe induced voltages in secondary cables with consequential influence on test results, possible destruction of measuring instruments and hazardous touch voltages for personnel. For analyzing transient potential differences, it is important to model, with maximum accuracy, impulse test circuit (impulse generator, chopping spark gap, voltage divider, Faraday cage, fundament earth electrode, earthing strips, earthing rods etc.). Magnitude of transient potential difference between particular points is proportional to earth electrode inductance, i.e. low inductance of earth electrode will result in decrease of transient potential difference.

Large and complex systems such as vehicles contain different structures and require various modelling methods and calculation due to the difference between components scales. One of the main issues in the automotive EMC (electromagnetic compatibility) is that the car is rarely available during the product's development phase, which means that more often, the product must be finalised before even it can be tested in its real environment. This article presents modelling techniques aiming at predicting the real performance of a RF (radio frequency) receiver ahead of its installation into a vehicle.

The FDTD method firstly proposed by K.S. Yee (see IEEE Trans., vol.AP-14, p.302-7, 1966) has been successfully applied to the numerical analysis of various electromagnetic problems, including scattering, antennas, microwave circuits and EM compatibility. Recently, FDTD formulations for some complex media, such as dispersive or anisotropic medium (see Luebbers, R.J. et al, IEEE Trans., vol.EMC-32, p.222-7, 1990; Schneider, J., et al, IEEE Trans., vol.AP-41, p.994-9, 1993) have been studied. However, the formulation of FDTD for bianisotropic medium has not been reported yet, due to the difficulty of treating the coupling between electric/magnetic constituents. In order to establish the FDTD formulae, both the iterative approximation in space difference and time difference are successfully employed. Furthermore, these formulae may be degenerated into the cases of anisotropic, isotropic or biisotropic media.