scholarly journals High-Frequency Electromagnetic Interference Diagnostics

2021 ◽  
Author(s):  
Ling Zhang ◽  
Yuru Feng ◽  
Jun Fan ◽  
Er-Ping Li
Keyword(s):  
Statistical Analysis ◽  
Electromagnetic Interference ◽  
High Frequency ◽  
Electromagnetic Compatibility ◽  
Measurement Techniques ◽  
Emission Source ◽  
Far Field ◽  
Large Network ◽  
Typical Type ◽  
Coupling Path

Electromagnetic interference (EMI) is becoming more troublesome in modern electronic systems due to the continuous increase of communication data rates. This chapter reviews some new methodologies for high-frequency EMI diagnostics in recent researches. Optical modules, as a typical type of gigahertz radiator, are studied in this chapter. First, the dominant radiation modules and EMI coupling paths in an explicit optical module are analyzed using simulation and measurement techniques. Correspondingly, practical mitigation approaches are proposed to suppress the radiation in real product applications. Moreover, an emission source microscopy (ESM) method, which can rapidly localize far-field radiators, is applied to diagnose multiple optical modules and identify the dominant sources. Finally, when numerous optical modules work simultaneously in a large network router, a formula based on statistical analysis can estimate the maximum far-field emission and the probability of passing electromagnetic compatibility (EMC) regulations. This chapter reviews a systematic procedure for EMI diagnostics at high frequencies, including EMI coupling path analysis and mitigation, emission source localization, and radiation estimation using statistical analysis.

Electromagnetic Compatibility Analysis Method for FBAR Devices

2015 ◽  
Vol 719-720 ◽  
pp. 452-460
Author(s):  
Yang Gao ◽  
Bin Zhou ◽  
Yi He ◽  
Wan Jing He
Keyword(s):  
Electric Fields ◽  
Electromagnetic Interference ◽  
High Frequency ◽  
Electromagnetic Compatibility ◽  
Effective Permittivity ◽  
Element Model ◽  
Acoustic Resonator ◽  
Simulation Software ◽  
Property A ◽  
Compatibility Analysis

With the increasing of resonant frequency and integration of film bulk acoustic resonator (FBAR), the electromagnetic interference (EMI) of FBAR devices appears to be extremely important. The electric fields of the common electrical model and finite element model are assumed to be quasi-static and cannot simulate the electromagnetic (EM) property. A 3-D EM model of FBAR is achieved by means of high frequency EM simulation software HFSS. A real-time simulation of EM distributed effects, EM coupling and piezoelectric effects is achieved by employing an effective permittivity in the EM model. The effects of the high frequency EM distributed effects and the EM coupling on resonant characteristics are analyzed. By optimizing the distance between FBAR and components, introducing substrate materials with different permittivity, the EM coupling is effectively reduced.

Reliability Design of Control Circuit for Quartz Crystal Feeding System

2014 ◽  
Vol 722 ◽  
pp. 222-225
Author(s):  
Tao Yan ◽  
Gui Qin Jin ◽  
Ze Ding Wei
Keyword(s):  
Electromagnetic Interference ◽  
High Frequency ◽  
Electromagnetic Compatibility ◽  
Quartz Crystal ◽  
Feeding System ◽  
Large Power ◽  
Laser Marking ◽  
Reliability Design ◽  
Crystal Laser ◽  
Design And Manufacturing

Quartz crystal laser marking is the last process of quartz crystal production, and quartz crystal automatic feeding system works in harsh environment, like high frequency, strong electromagnetic interference, static electricity and large power, and feeding system itself also contains many electromagnetic interference factors, To ensure the system working stably and reliably, in the design and manufacturing of control system, using high quality components, the reasonable wiring and grounding, in the aspect of electromagnetic compatibility, hardware and software anti-interference measures were taken. Through a lot of test working in the laboratory and field, and the design scheme was modified for many times, it finally makes that the feeding system is so stable in the workplace that it could meet the requirements of the customer, and it has a certain guiding significance for the design of other mechanical and electrical products production.

scholarly journals Analysis of Permanent Magnet Motors in High Frequency—A Review

2021 ◽  
Vol 11 (14) ◽  
pp. 6334
Author(s):  
Yerai Moreno ◽  
Gaizka Almandoz ◽  
Aritz Egea ◽  
Beñat Arribas ◽  
Ander Urdangarin
Keyword(s):  
Finite Element ◽  
Electromagnetic Interference ◽  
High Frequency ◽  
Electromagnetic Compatibility ◽  
Equivalent Circuit Model ◽  
Design Parameters ◽  
Electrical Machine ◽  
Element Analysis ◽  
Electrical Equivalent Circuit ◽  
Electric Drives

Electric drives consume a great amount of the world’s energy, and it will keep increasing due to the electromobility trend. Thus, the efficiency of electric drives must be improved to reach the desired sustainability goal. The Silicon Carbide devices contribute to this objective due to their high working frequency and lower switching losses. However, working at higher frequencies may bring serious Electromagnetic Compatibility (EMC) problems, as well as insulation stress and higher bearing currents. Hence, it is important to have an electrical machine electrical equivalent circuit model to predict the electromagnetic interference levels. This review summarizes the current state of the art in electrical machine modeling and analysis in high frequency. The main analysis tools as Finite Element Methods, analytic and measurement-based tools are compared in their application on high-frequency electrical machine analysis. Then, different machine high-frequency models are reported, detailing their individual features. Additionally, the influence of the machine design parameters in EMC behavior is outlined for future analysis. All in all, Finite Element analysis is the most accurate tool for high-frequency analysis, provided that mesh size is thinner than the skin depth. It is also concluded that the winding placement is an essential parameter to define the high-frequency behavior of the machine.

scholarly journals Electromagnetic Spectrum of the Corona Discharge and Their Fundamental Frequency

2021 ◽  
Author(s):  
Luis E. Martínez Santos ◽  
Roberto Linares y Miranda ◽  
Fermín P. Espino-Cortés
Keyword(s):  
Corona Discharge ◽  
Electromagnetic Interference ◽  
High Frequency ◽  
Communication Systems ◽  
Electromagnetic Compatibility ◽  
Design Criterion ◽  
Past Century ◽  
Electromagnetic Spectrum ◽  
Radio Communication ◽  
High Voltage Direct Current

Historically, the Electromagnetic Compatibility (EMC) began with the disturbances at the radio navigation systems generated by the electrical power distribution lines; hence it was referred to as Radio Interference (RI). This disturbance is an Electromagnetic Interference (EMI). Although this type of EMI has been studied since the first decades of the past century, it still maintains a continued interest of the researchers, especially with the Corona Discharge (CD), generated by High Voltage Direct Current (HVDC) systems. Because of its design criterion and the concern that this phenomenon may affect the new radio communication systems in the very high frequency (VHF), ultra high frequency (UHF), and microwave bands, interest in their studies continues. In this chapter, an analysis of the electromagnetic spectrum of the CD is presented. The CD is generated at a short transmission line located within a semi-anechoic chamber. To be sure of the phenomenon, the CD is identified by its current pulse, which is well studied. The instruments used are an oscilloscope of 2 GHz and 2 GS/s, a spectrum analyzer, and an EMI test receiver. The results show that the CD concentrates its energy at frequencies below 70 MHz. In the UHF band, only narrowband signals very separated were found, with levels that cannot affect radio communication systems.

scholarly journals A General Transformer Evaluation Method for Common-Mode Noise Behavior

Energies ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1984
Author(s):  
Kaining Fu ◽  
Wei Chen ◽  
Subin Lin
Keyword(s):  
Electromagnetic Interference ◽  
High Frequency ◽  
Evaluation Method ◽  
Power Converters ◽  
Common Mode ◽  
Coupling Capacitance ◽  
Class B ◽  
Coupling Path ◽  
Transformer Coupling ◽  
Testing Instruments

In isolated power converters, the transformer is a key part of voltage transformation and isolation. Since common-mode (CM) noise is rather difficult to suppress compared with different-mode (DM) noise, more and more scholars are paying attention to the characteristics of CM noise, especially in high-frequency CM noise behaviors. CM noise can be further divided into conducted CM noise and radiated CM noise, and the main focus of this paper is on conducted CM noise. The CM coupling capacitance of the transformer is one of the main contributors of CM noise, which has been verified in many previous studies. Hence, eliminating the CM noise in a transformer coupling path can significantly lower the whole CM noise level of the converter. Professional conducted electromagnetic interference (EMI) testing instruments are quite expensive. In this paper, a general transformer evaluation technique for CM noise behavior is proposed. Only a signal generator and oscilloscope can achieve transformer CM noise behavior evaluation. PCB planar flyback transformers are designed, and a series of noise spectrums and voltage waveforms can verify the effectiveness of the proposed transformer evaluation method. The flyback adapter porotype can pass the EMI standard limited line EN55022 class B by the proposed evaluation method.

scholarly journals A Brief Introduction in the Mitigation of Conducted Electromagnetic Interference lssues

2021 ◽  
Vol 19 ◽  
pp. 373-378
Author(s):  
M. Buzdugan ◽  
Keyword(s):  
Electromagnetic Interference ◽  
Electromagnetic Compatibility ◽  
Low Voltage ◽  
Frequency Converter ◽  
Measurement Techniques ◽  
Power Lines ◽  
Frequency Range ◽  
Electromagnetic Emissions ◽  
Interference Tests ◽  
Conducted Emissions

This paper deals with the mitigation of the influence of electromagnetic conducted emissions in low voltage grids, which can be performed using different filtering methods. Due to the relatively young age of the electromagnetic compatibility domain, the specific terminology is not yet fully consecrated. That is why the specific literature abounds in a bunch of definitions and notions, incomplete, redundant, or worse, even contradictory. Therefore, all over this paper, the terminology from the successive issues of the standard IEC 60050-161 International Electrotechnical Vocabulary, is used. The introductory section presents generalities regarding the broader context of electromagnetic compatibility in which the paper fit. Section II is devoted to measurement techniques and measuring equipment used in conducted electromagnetic interference tests, specifically for electromagnetic emissions that flow in/from the equipment under test through power lines in the standardized frequency range from 100 kHz to 30 MHz. These measurement techniques and equipment are further used in the next section which presents electromagnetic interference experiments, performed on an induction motor driven by a frequency converter. To mitigate the conducted electromagnetic emissions to fit into the standard limits, a cascade of two EMI filtering cells has been designed and implemented. This demonstrated the usefulness and effectiveness of mains EMI filters in low voltage power applications. The experiment also demonstrated that in some cases it would be necessary to retrofit more than one filtering cell

Sign in / Sign up

Export Citation Format

Share Document