Electromagnetic Interference Analysis Research Articles

Modeling and Analysis of Environmental Electromagnetic Interference in Multiple-Channel Neural Recording Systems for High Common-Mode Interference Rejection Performance

Environmental electromagnetic interference (EMI) has always been a major interference source for multiple-channel neural recording systems, and little theoretical work has been attempted to address it. In this paper, equivalent circuit models are proposed to model both electromagnetic interference sources and neural signals in such systems, and analysis has been performed to generate the design guidelines for neural probes and the subsequent recording circuit towards higher common-mode interference (CMI) rejection performance while maintaining the recorded neural action potential (AP) signal quality. In vivo animal experiments with a configurable 32-channel neural recording system are carried out to validate the proposed models and design guidelines. The results show the power spectral density (PSD) of environmental 50 Hz EMI interference is reduced by three orders from 4.43 × 10−3 V2/Hz to 4.04 × 10−6 V2/Hz without affecting the recorded AP signal quality in an unshielded experiment environment.

Research and analysis of electromagnetic interference of a motor drive control system based on PMSM with SiC MOSFET for new energy electric vehicles

Sustainable development in the 21st century faces significant challenges due to finite reserves of fossil fuels and environmental pollution. In the context of new energy electric vehicles (NEEVs), the wide-bandgap semiconductor known as the silicon carbide–metal oxide–semiconductor field-effect transistor (SiC MOSFET) and the permanent magnet synchronous motor (PMSM) have emerged as advantageous sources. However, the use of these components gives rise to electromagnetic interference (EMI) issues, which impede the achievement of electromagnetic compatibility (EMC) standards in the motor drive control system. This paper aims to elucidate the generation mechanism, propagation path, and test infrastructure of EMI. Furthermore, it proposes a system-level conducted EMI equivalent circuit model for the motor drive control system, encompassing the power battery pack, busbar cable, LISN, three-phase inverter, and PMSM. Building upon this foundation, the principles for suppressing and optimizing EMI noise are discussed. The paper concludes with the validation of simulations and experimental results, which demonstrate the effectiveness of the proposed approach. It is anticipated that professionals with an interest in the field of EMI/EMC will find this paper to be of both theoretical and practical importance.

Analysis and Protection of Electromagnetic Interference in the Industrial Field

With the continuous progress of science and technology, all kinds of electrical and electronic equipment are applied to production and life. However, bad electromagnetic interference will affect the normal operation of the equipment and reduce work efficiency. This paper analyzes the situation and source of electromagnetic interference in the industrial field and introduces several common anti-interference methods. And take corresponding measures according to different types of interference. This paper introduces electromagnetic shielding, filtering, and other technologies, and the application scenarios of various anti-interference methods are analyzed. When the working environment and the nature of interference emission change, the anti-interference strategy should be adjusted accordingly. Implementing these measures will significantly improve the electromagnetic compatibility of the system, reduce the electromagnetic interference phenomenon in the industrial site, and ensure the stable and efficient work of the system. Although electromagnetic interference cannot be eliminated, summarizing and analyzing existing technologies helps to develop new technologies and provides more possibilities for anti-interference.

Research on explosive electromagnetic field interference analysis based on field-circuit cooperated modeling and simulation

Research on explosive electromagnetic field interference analysis based on field-circuit cooperated modeling and simulation

Investigation and Analysis of Electromagnetic Interference for PWM Encoder of Urban Rail Train

Electromagnetic compatibility (EMC) is an important factor in ensuring the safe operation of the sensitive electronic equipment on urban rail trains. The pulse width modulation (PWM) encoder of an urban rail train exported from China to Brazil is sometimes affected by electromagnetic interference (EMI), which causes the train to fail to run properly. To solve this problem, the EMC test is performed on the PWM encoder to identify the coupling path and the type of interference source. The EMI coupling model and the vehicle-catenary-rail model are established by using an electromagnetic transients program (EMTP) to analyze the mechanism of interference coupling. It is shown that the unbalanced voltage of the train body caused by the backflow of the grounding current is the root cause of the interference of the PWM encoder. The maximum voltage coupled to the internal port of the PWM encoder is about 1894 V, which is sufficient to burn out the encoder. A measure to suppress the interference by installing thyristor surge suppressors (TSS) P0300SC is proposed, which effectively solves the EMI problem of the PWM encoder.

An efficient dual-scale method for analysis of EMI problems resulted from radiation sources

An efficient dual-scale method, which integrates parabolic equation (PE) with electric field integral equation (EFIE) formulated via the Rao-Wilton-Glisson moment method (RWG-MOM), is proposed to analyze the electromagnetic interference (EMI) problems resulted from radiation sources. This method is implemented by decomposing the original intractable multi-scale problem domain into two sub-regions: (1) modeling of the complicated ambient electromagnetic fields by PE and (2) solution of the fields coupling to the exposed electronic devices by RWG-MOM. Frequency-sweep and Fourier synthesis techniques are applied to calculate the transient currents and voltages. The proposed method is able to fully model the disturbances of the electromagnetic fields by multi-path effects. Besides, it reduces the memory footprint and the CPU computing time effectively compared to the traditional full-wave electromagnetic methods. Numerical examples are presented, and the simulation results indicate that this method is well suitable for the EMI analysis of external radiation sources.

Analysis of Electromagnetic Interference for Anti-Medal UHF RFID Temperature Tag in High Power Electronic Equipment

Being inches from the rapid development of new energy technology, the capacity of high-power power electronic equipment is increasing rapidly, and the requirements for its safe and reliable operation are also rising. As a result, the demand for online temperature monitoring of such equipment is becoming increasingly urgent. RFID temperature measurement technology can be used for real-time monitoring of the temperature of powered operation equipment. However, the operation of high-power electronic equipment generates strong electromagnetic interference, which can seriously affect the normal operation of RFID temperature measurement systems. For applications involving the internal temperature measurement of high-power power electronic equipment, this paper employs an RFID anti-metal temperature tag antenna with a short-circuit cutoff structure. This structure was tested in an excitation switchgear cabinet. During the low-power operation of the cabinet, the temperature tag functioned normally. By combining an RFID antenna model with an electromagnetic interference simulation model of the main circuit of the excitation switchgear cabinet, this paper establishes an electromagnetic interference simulation model for an RFID temperature tag. It analyzes how the tag’s antenna performance parameters change when subjected to interference. Through simulation, the failure mechanism of the RFID temperature tag during the high-power operation of the excitation switchgear cabinet is clarified. The analysis found that there are both conductive electromagnetic interference and radiated electromagnetic interference in the excitation switchgear cabinet, with the conductive electromagnetic interference having a more significant effect. Conductive electromagnetic interference can seriously impact the performance of RFID temperature tags in the excitation switchgear cabinet, significantly degrading their performance. In contrast, the effect of radiated electromagnetic interference on the tags is relatively small. Therefore, this paper employs anti-metal RFID temperature tags and simulates and analyzes their electromagnetic interference characteristics.

FLARE: A Framework for the Finite Element Simulation of Electromagnetic Interference on Buried Metallic Pipelines

The functionality of buried metallic pipelines can be compromised by the electrical lines that share the same right-of-way. Given the considerable size of shared corridors, computer simulation is an important tool for performing risk assessment and mitigation design. In this work, we introduce an open-source computational framework for the analysis of electromagnetic interference on large earth-return structures. The developed framework is based on FLARE—an efficient finite element solver developed by the authors in MATLAB®. FLARE includes solvers for problems involving static electric and magnetic fields, and DC and time-harmonic AC currents. Quasi-magnetostatic transient problems can be studied through time-marching or—for linear problems—with an efficient inverse-Laplace approach. In this work, we succinctly describe the optimization of time-critical operations in FLARE, as well as the implementation of a transient solver with automatic time-stepping. We validate the numerical results obtained with FLARE via a comparison with the commercial software COMSOL Multiphysics®. We then use the validated time-marching analysis results to test the accuracy and efficiency of three numerical inverse-Laplace algorithms. The test problem considered is the assessment of the inductive coupling between a 500 kV transmission line and a metallic pipeline buried in the soil.

A Novel Toolbox for Induced Voltage Prediction on Rail Tracks Due to AC Electromagnetic Interference Between Railway and Nearby Power Lines

AC electromagnetic interference (EMI) between railway and nearby power lines causes serious concerns about railway personnel and equipment safety. The AC EMI analysis is usually conducted by complex computer simulation software to estimate induced voltages on rail tracks, and induced voltages can be further used for safety evaluation. However, such analysis becomes especially difficult at the transmission line routing stage when only limited information of railway and power lines is available. To overcome this challenge, a novel regression model-based toolbox is developed in this paper to predict induced voltages on rail tracks. To develop this toolbox, the dataset acquisition is critical due to very limited research done in this area. The novel dataset is produced by our newly developed AC EMI study method, where variations of several essential factors are considered, including the power line's current, the separation distance between power lines and railway, the ballast resistance, and the length of rail tracks. Two models are eventually chosen to predict induced voltages: “Gaussian process regression” with “matern 3/2” kernel function; and a tri-layered “neural network” model with “sigmoid” activation function. To improve the accuracy, hyperparameters of the regression algorithms are optimized by Bayesian optimization. The toolbox is accurate and easy-to-use, and is currently in use by Manitoba Hydro, Canada.

Analysis of Intentional Electromagnetic Interference on GENEC Model Using Cylindrical Mode Matching

In recent times, due to the high operating frequency and low operating voltage of modern electronic devices, intended electromagnetic interference (IEMI) has been the cause of increasing damage. In particular, targets with precision electronics such as aircrafts or missiles have shown that a high-power microwave (HPM) may cause malfunction or partial destruction of the GPS or the avionic control system. Analysis of the effects of IEMI requires electromagnetic numerical analyses. However, there are limitations to conventional numerical techniques, such as the finite element method, method of moment, or finite difference time domain method, due to the complexity and large electrical length of a real target system. In this paper, we proposed a new cylindrical mode matching (CMM) technique to analyze IEMI of the generic missile (GENEC) model, which is a hollow metal cylinder with multiple apertures. Using the CMM, we can quickly analyze the effect of the IEMI inside the GENEC model from 1.7 to 2.5 GHz. The results were compared with those of the measurements and, for verification, with the FEKO, a commercial software program developed by Altair Engineering, and showed good agreement. In this paper, the electro-optic (EO) probe was used to measure the electric field inside the GENEC model.

Analysis of Common-Mode Noise and Mixed-Mode Differential-Mode Noise in Dual Active Bridge Converter

The dual active bridge (DAB) converter is one of the widely explored topologies in recent years due to its remarkable features, such as inherent soft-switching characteristics, galvanic isolation, and high power density. However, the conducted electromagnetic interference (EMI) analysis of the DAB converter is seldom reported. In this article, the common-mode (CM) and the differential-mode (DM) equivalent circuits of the isolated DAB converter are presented to understand the propagation mechanisms of the conducted EMI noise in the converter. In particular, the mixed-mode DM (MMDM) noise component of the DM noise is quantified for the DAB converter. Furthermore, an experimental measurement method based on an external impedance-matched circuit is proposed to quantify the DM current due to capacitive coupling between the primary and secondary windings of the transformer. The quantified MMDM noise and the DM noise through the transformer are estimated using the proposed equivalent circuits in MATLAB-Simulink and validated experimentally on a prototype DAB converter.

Probe Design and Source Reconstruction for Near-Field Scanning and Modeling

This paper elaborates the near-field scanning and modeling technique developed for electromagnetic interference (EMI) analysis. The technique has been increasingly deployed in many R&D labs of universities and testing centers of industry companies due to its advantages in terms of time and cost, comparing with conventional EMI measurement methods. The major research works related to the near-field scanning and modeling are probe design and source reconstruction method (SRM). In this article, the working principle of electric and magnetic probes are firstly introduced. Probe parameters including calibration factor, electric center, sensitivity, spatial resolution and bandwidth are discussed. Next, the equivalent radiation source modeling approach is presented. Through SRM, a complex and unknown EMI source is substituted with the simplified equivalent radiation source based on the electromagnetic fields measured by magnetic and/or electric probes. The phaseless SRM is thereafter discussed for addressing the limitations in conventional SRM and its applications prove that the near-field scanning and modeling technique can effectively predict EMI far-field radiation and near-field coupling.

Electromagnetic interference measurement for axle counters light rapid transit railway in Indonesia

The measurement and analysis of electromagnetic interference (EMI) from light rapid transit (LRT) axle counters against magnetic field interference in Indonesia has been carried out. The low-cost magnetic sensors were developed according to the British Standard (BS) EN 50592:2016. The measurement setup and magnetic field limit were based on the British Standard EN 50592:2016 and ERA/ERTMS/033281 standard. Two frequency range of the measurements, lower and higher frequencies with two different train running mode, acceleration mode and deceleration mode were applied in this research. The results in lower frequency range (10 to 100 kHz) were very close to the limit value in both acceleration and deceleration mode, especially at the 30 to 50 kHz for the y and z directions. Although there may possibly magnetic interference at low frequencies, most of the magnetic field emissions were still in acceptable range.

Conducted EMI analysis and filters design for a high-low voltage DC/DC converter based on GaN HEMTs in electric vehicle

PurposeThe purpose of this paper is to study conducted electromagnetic interference (EMI) of the high-low voltage DC/DC converter based on GaN high-electron-mobility transistors (HEMTs) in electric vehicle, and design EMI filters to suppress the conducted EMI.Design/methodology/approachThe conducted EMI propagation model is established through simulation and analysis studying the influences of parasitic parameters, operation mode, output power and near-field capacitive coupling effects on conducted EMI of the DC/DC converter and comparing the suppression effects of EMI filters with different topologies to select the best EMI filter.FindingsIt is shown that parasitic parameters, operation mode, output power and near-field capacitive coupling effects can affect the conducted EMI of the DC/DC converter, and EMI filters of the CLC topology can effectively suppress the conducted EMI below the limit of CISPR 25.Originality/valueAnalysis of conducted EMI and design of EMI filters greatly facilitate further explorations and studies on EMI problems of the high-low voltage DC/DC converter based on GaN HEMTs.

Electromagnetic interference analysis and measures of the antenna servo system of ship-borne satellite communication

This paper analyzes the working principle of servo drive, introduces the interference source of electromagnetic interference, and summarizes the damage caused by electromagnetic interference. Based on the characteristics of the ship's electromagnetic environment, the suppression measures of the electromagnetic interference of the ship servo drive are proposed.

Experiment and theoretical analysis of electromagnetic interference on communication systems in multi-rails environment

Purpose Electromagnetic interference (EMI) on communication systems of unban rail transit can hardly be clarified because of complicated factors around railways. This paper aims to target this issue and extend experimental and theoretical analysis. Design/methodology/approach This paper take the Nanjing Dashengguan Bridge as an example, because it carries the most tracks in the world and bears three kinds of trains running through, providing a perfect complex environment. First, it investigates the three communication systems, terrestrial trunked radio, communications-based train control (CBTC) and passenger information system (PIS) that Nanjing Metro uses, and select appropriate devices accordingly. Second, it establishes a system level platform and conduct three tests to analyze their respective operating principles and performance difference under common electromagnetic environments. Third, it adopts theoretical formula to verify test results. Findings The experiment results and theoretical analysis mutually corroborate each other and present practical recommendations: an 8 m or more distance between two tracks will ensure no obvious EMI created by a passing train on communication systems; two certain communication systems should not share the same frequency band; interference level is more related to field strength than weathers and building materials; and CBTC DSSS waveguide mode as well as PIS LTE mode are preferred. Originality/value This research also provides a practical method of investigating EMI for other complex situations.

Analysis and Suppression of Conducted Common-Mode EMI in WBG-Based Current-Source Converter Systems

The adoption of wide bandgap (WBG) devices in power converters creates challenging conducted common-mode (CM) electromagnetic interference (EMI) issues due to their fast-switching transients and high switching frequencies. This article focused on the analysis and suppression of CM EMI for WBG-enabled three-phase current-source converters (CSCs) consisting of back-to-back rectifier and inverter stages, which have received little attention in the literature. The baseline time-domain waveforms and CM EMI of CSC have been experimentally characterized, showing that even though CSCs have high-quality sinusoidal input–output voltage and current waveforms, their CM EMI still exceeds existing EMI standards. To suppress the CM EMI, the effects of adding different EMI filters at different locations in the CSC topology are evaluated. Based on CSC’s circuit operation and analytical derivation, a CM EMI equivalent circuit (EQC) is proposed for the back-to-back CSC configuration. The proposed EQC achieves fast and accurate CM EMI estimation for CSC using different filtering techniques. Based on the proposed EQC and evaluations of different filter methods, an effective filtering scheme is proposed for the CSC that achieves significant CM EMI attenuation throughout the frequency range from 150 kHz to 30 MHz.

Predictive Modeling for Detection of Source of Electromagnetic Disturbances in Inductive Wireless Charging of Electric Vehicles

The effects of Electromagnetic Interference (EMI) in Inductive Power Transfer (IPT) for electric vehicle charging circuits are elaborated with Common Mode (CM) emission. Electromagnetic Compatibility (EMC) has to be sustained in the circuits such that it is prone to the effects of interferences, noises and disturbances. These issues can be addressed at the initial product development stage, with accurate identification of the parameters that influence the CM emission in the circuit. The analysis of EMI focuses on three features, namely Source of EMI, Coupling path and Receptor. In the IPT model, the primary source of the EMI is the power converter used for high-frequency supply to the inductive coils. The power converter switches and the heat sink with its Printed Circuit Board (PCB) design are predominant in power electronic circuits. This paper facilitates the reduction of EMI without including complex filters. The system is tested for the violated standard SAEJ2954. In addition, the article corroborates precognitive modeling by implementing compensation networks used in IPT applications and their effectiveness in reducing the leakage current caused by the converters and the coils. The paper insights the air gap variation of the coil with the power transfer efficiency and its influence on electromagnetic interferences. The Fast Fourier Transform (FFT) analysis used in PSIM shows leakage current and harmonic reduction with the compensation network and Pulse Width Modulation (PWM) technique. The fabrication model for the front end power supply to the IPT is tested. The electrical noise emission is estimated using predictive modeling.

Analysis of Electromagnetic Interference and Shielding in the μLED Optrode Based on Finite Element Method

Monolithic integrated μLED optrode has promising applications in optogenetics due to their ability to achieve more optical channels in a smaller footprint. The current used to drive the μLED will cause electromagnetic interference (EMI) noise to the recording electrodes at a very close distance. Utilizing a grounded metal shielding layer between the active device and the electrode can potentially reduce the interference. In this paper, multi-dimensional μLED optrode models are set up according to the real device. By numerically analyzing the electromagnetic interference between the μLED and recording electrodes, several optimized shielding schemes are evaluated by simulations and experiments. Some important process and layout parameters that may influence the shielding effect are studied through the finite element method (FEM). Different circuit models based on the corresponding test environment are built to analyze the simulation and experiment results. A new PCB with a shielding layer has been designed and initially verified. The proposed novel computational model can analyze EMI quantitatively, which could facilitate the design of low-noise μLED optrode with reasonable shielding and packaging.

Prediction and Analysis of Conduction Electromagnetic Interference in Communication Power

Conducted electromagnetic interference (EMI) in power electronic equipment is an important factor restricting the development of power electronics technology, and the research is of great hot and difficulty. The prediction of conducted EMI is to effectively guide the design of EMI filters. On the one hand, the selection of commonmode capacitance and inductance values can be guided by the analysis of propagation path impedance; on the other hand, various passive devices are analyzed by simulation the influence of parasitic parameters on conducted EMI can guide the selection of filter capacitors and inductors. In this paper, we take the widely used switching power supply as an example, a novel EMI conduction modelling is proposed, the impedance analysis method is used to model the high-frequency parasitic parameters, the model was built for predicting the conducted EMI accurately of switching power supply.