Sources Of Electromagnetic Interference Research Articles

Research on ultra-wideband electromagnetic pulse irradiation effect and protection method of Unmanned Aerial Vehicle

The data link is an important guarantee for the Unmanned Aerial Vehicle (UAV) equipment to complete its battlefield functions. Its anti-electromagnetic pulse interference capability directly affects the airborne communication security. Ultra-wideband (UWB) electromagnetic pulse has become an important source of electromagnetic interference due to its high power, wide frequency band and wide interference target. In order to verify the reliability of UAV data link communication under UWB electromagnetic pulse irradiation conditions, the UWB electromagnetic pulse irradiation effect experiment of UAV was carried out, and the mechanism of “lost lock” effect of UAV data link was analyzed. The experimental results show that when the UWB electromagnetic pulse irradiation intensity reaches 140 kV / m, it will cause hardware damage to the UAV, and found that its internal sensitive device low noise amplifier is damaged. In response to this, the comprehensive design of the electromagnetic protection measures for the UAV was carried out, laying the foundation for the next step to strengthen the electromagnetic protection of the UAV.

Shaping SiC MOSFET Voltage and Current Transitions by Intelligent Control for Reduced EMI Generation

In power converters, the fast switching of the power conversion components results in rapid changes in voltage and current, which results in oscillations and high-level electromagnetic interference (EMI), so the power components become a source of internal electromagnetic interference. Taking SiC Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) as an example, an intelligent control method to suppressing interference sources is proposed in this paper. The combination of open-loop and closed-loop methods can simultaneously reduce the electromagnetic interference generated by voltage and current. Firstly, this paper analyzes how to select a reference signal. The relationship between the time domain and the frequency domain of the noise signal is analyzed. The convolution of the trapezoidal signal and the Gaussian signal is selected as the reference signal, which is named S-shaped signal in this paper. The S-shaped signal has continuous infinitely conductive characteristics, so its spectrum has a large attenuation in the high frequency region. Secondly, a new topology is proposed. Based on the closed-loop gate control, a current control signal is added, which can simultaneously shape the output voltage and control the output current slope. Both the simulation results and the experimental results show that the output voltage can follow the reference signal, S-shaped signal, and the slope and overshoot of output current can be changed. Compared with classical gate driver method, the spectrum of output voltage and output current obtained by the method proposed in this paper has a large attenuation, in other words, the electromagnetic interference is significantly reduced.

Localization and Frequency Identification of Large-Range Wide-Band Electromagnetic Interference Sources in Electromagnetic Imaging System

The identification and localization of large-range, wide-band electromagnetic interference (EMI) sources have always been both costly and time-consuming. The measurements at different times and places are often required before a typical system can locate a target. In this paper, we proposed a 2D electromagnetic imaging system to localize interference sources and identify the EMI frequency in real time. In this system, an offset paraboloid with a diameter of three meters is designed for large-range EMI imaging, while a multi-channel digital signal acquisition system is developed for wide-band EMI localization. The located interference source is segmented by the maximum entropy method based on particle swarm optimization, and the modified generalized regression neural network (MGRNN) is applied to identify the EMI frequency effectively by excluding misleading effects of outliers. The experiment which has been completed on our dataset indicates that our approach not only increases accuracy by 5% compared with the standard generalized regression neural network approaches for identification, but also exerts a large-range wide-band localization of the EMI source detection method.

An Equivalent Dipole Model Hybrid With Artificial Neural Network for Electromagnetic Interference Prediction

A new equivalent dipole model hybrid with artificial neural network (ANN) is proposed in this paper for electromagnetic interference (EMI) estimation. Equivalent dipole method, based on the free-space Green’s function, is usually used to model unknown EMI sources on printed circuit boards. For high-speed and dense circuits, there may be multi-reflection and/or diffraction between the EMI source and its nearby components. Traditional dipole model usually omits such effects and leads to an inaccurate result in some cases. In our proposed method, the Green’s function of dipole is taken as input and the radiated EMI field is taken as the output of ANN. We use the powerful mapping ability of ANN to modify the matrix–vector multiplication between free-space Green’s function and dipole moments in the traditional dipole model, so that a new mapping between equivalent dipoles and their radiated fields is established. The near field of the EMI source is obtained by planar scanning, and is used for ANN training. After training, the ANN is used to predict the EMI field at the region of interest. Both numerical example and measurement example are given to show the effectiveness of the proposed ANN method. This paper provides a novel source reconstruction solution for the EMI problems.

Cardiac implantable electronic devices : Electromagnetic interference from electrocauterization, lithotripsy and physiotherapy

The management of patients with acardiac implantable electronic device (CIED) poses aparticular challenge in the peri-interventional and perioperative medical environment due to the many forms of possible electromagnetic interference. Although the devices encountered nowadays are of increasing complexity, the vast majority of procedures can be safely performed in patients. The existing position statements and recommendations, however, have alow level of evidence and are often contradictory. In the context of intraoperative electrocauterization, one of the most important sources of electromagnetic interference in the medical environment, recent studies have suggested an increasingly pragmatically perioperative CIED management, which is not represented in the existing recommendations. This article gives an example of these newer findings and reports the currently used and appropriately adapted perioperative CIED management protocol. Extracorporeal shock wave lithotripsy was thought to cause severe interference in CIED patients based on older studies and in vitro experiments. Although electromagnetic interference is possible, clinical observations with modern devices show that the procedure can generally be safely applied in CIED patients. Physiotherapy often utilizes avariety of electromechanical devices, which can be a relevant source of electromagnetic interference. Although some of these therapies can be safely used, coordination with the responsible CIED unit is recommended.

Development of mobile electrical vehicle for EMI applications

This paper presents the relevancy, design, and test results of a mobile electrical vehicle for the applications of testing and providing electromagnetic interferences in Wi-Fi signal in the band 2.4–2.5 GHz. The mobile device includes power electronics supplying a magnetron device for the interference. Propulsion of the mobile device is implemented by using a system of stepper motors. The mobile device is controlled with the help of the microcontroller ATmega 16. For the interfering part, it is necessary to design the power electronics to supply the magnetron from the battery. The power electronics interface between a battery and magnetron must be able to transfer output battery voltage 12 VDC to the variable output 4000 VAC and power around 1 kW. The magnetron is used as a source of electromagnetic interference high-frequency acting on targets, which operates in the band of Wi-Fi signal. In addition, the system must be able to control the direction and power of EMI interferences. The investigations of the power-efficiency of power inverter versus power density will be discussed and optimised here.

Analysis and optimization of electromagnetic compatibility for electric vehicles

Due to the changes of energy storage sources, driving systems, vehicle control units, etc., the electromagnetic compatibility (EMC) of electric vehicles is facing greater challenges than that of conventional oil-fueled vehicles. On the one hand, the use of high-power and high-voltage electrical components will generate high electromagnetic interference (EMI) energies in actual operation. On the other hand, automotive electronics with high integration and sensitivity is more susceptible to EMI, which is directly related to the safety of vehicles. In this paper, the EMI mechanism and suppression measures of motor driving systems, charging systems and other low-voltage systems are investigated. The results show that the main sources of EMI in electric vehicles are the quick switching of power switches, the operation of motor windings and the issue of signal coupling between high voltage cables and low voltage cables, and the EMI can be suppressed effectively by shielding, filtering and optimization of system principles.

Reduction of susceptibility from electromagnetic interference in sensorless FOC of IPMSM

This paper presents main problems of practical implementation of Field Oriented Control (FOC) developed for an Interior Permanent Magnet Synchronous Motor (IPMSM). The main sources of Electromagnetic Interferences (EMI) noises are discussed and practical aspects when a position sensor is used are presented. The control system is based on the DSP processing unit, together with inverter and encoder. The main problem addressed in this paper is reduction of vibrations in torque and speed response in a real system by re-placing a hardware device of control system very susceptible to EMI noises, like encoder, with a soft block in control unit like Sliding Mode Observer, less sensitive to EMI. The experimental results with this control structure show considerable ripple reduction at steady state in torque, speed and current, as a consequence of reduction of sensitivity to EMI noises.

Design of Interfering Mobile Device in the Band Wi-Fi with Magnetron

The aim of this article is to design an interfering mobile device with a magnetron for the interference in Wi-fi signal in the band 2.4-2.5GHz. Propulsion of the interfering mobile device will be implemented using system of the stepper motor, which will be controlled with the help of the microcontroller ATmega 16. In order to deal with the interfering part, it is necessary to design an inverter 12V/4000V and 50-60Hz. The inverter is a supply of the high-powered vacuum tube that generates microwaves; magnetron. Magnetron is used as a source of electromagnetic interference high-frequency acting on targets, which operates in the band of Wi-Fi signal. For example, waves of high-frequency radio damage on-board electronic devices of the UAV, and by the way, we can disable fly of UAV in demarcated areas. The interfering mobile device will be used as a preparation interference and measurement electromagnetic compatibility of electronic military equipment.

Active EMI Reduction Using Chaotic Modulation in a Buck Converter with Relaxed Output LC Filter

DC-DC buck converters are widely used in portable applications because of their high power efficiency. However, their inherent fast switching releases electromagnetic emissions, making them prominent sources of electromagnetic interference (EMI). This paper proposes a voltage-controlled buck converter that reduces EMI by using a chaotic pulse-width modulation (PWM) technique based on a chaotic triangular ramp generator. The chaotic triangular ramp generator is constructed from a simple on-chip chaotic circuit linked with a symmetrically triangular ramp circuit. The proposed converter can thus operate in the chaotic mode reducing the EMI without requiring any EMI filters. Additionally, using the triangular ramp signal can relax the requirement for a large LC output filter in chaotic mode. The effectiveness of the proposed scheme was experimentally verified with a chaotic triangular ramp generator embedded in a voltage-mode controller buck converter using a 0.18 µm Complementary Metal Oxide Semiconductor (CMOS) process. The measurement results from a prototype showed that the EMI improvement from the proposed scheme is approximately 14.53 dB at the fundamental switching frequency with respect to the standard fixed-frequency PWM reference case.

Improvement of Low-Frequency Radiated Emission in Electric Vehicle by Numerical Analysis

In this paper, a methodology for improving vehicle-level radiated electromagnetic interference (EMI) in electric vehicle (EV) is proposed. This methodology predicts vehicle-level radiated EMI by using the multiport network theory, based on analyzing the contribution from each electronic component to find out the main EMI source. To validate its effectiveness, the proposed methodology is applied in an actual EV for low-frequency radiated emissions. Simulation in a commercially available electromagnetics software and measurement in the EV are combined to predict the vehicle-level emissions, and then the electronic component with the greatest EMI that causes failure to meet the EMC standard is identified. After improving this component, the vehicle-level radiated emission is reduced to comply with the EMC standard, proving that the presented numerical method is effective. The proposed methodology can also be used in other EMC issues, regardless of the amount of interference sources and sensitive equipment.

An Iterative Approach for EMI Source Reconstruction Based on Phaseless and Single-Plane Near-Field Scanning

Electromagnetic interference (EMI) source reconstruction typically requires accurate measurements of both near-field magnitude and phase information. In some cases, an accurate phase measurement may not be practically feasible. A phase-retrieval method based on phaseless and single-plane near-field scanning is presented in this paper. By using an interpolation technique, the original data of field magnitude used for reconstruction can be divided into two groups: the sampling and interpolation groups. Subsequently, iteration algorithm together with the singular value decomposition method is employed to reconstruct the equivalent dipole model of the EMI source. Both numerical example and measurement example are given to verify the effectiveness of the proposed algorithm. The major advantage of the proposed method is that it can save a half scanning time and still produces a valid EMI source model. It also shows an ability to reduce some measurement errors.

Commercial arc fault detection devices in military electromagnetic environment

Arc fault detection device (AFDD) is the latest protection device for low voltage circuits. It is used to detect arcing faults that cannot be detected by circuit breakers or residual current devices. Arcing faults are one of the main causes for electrical fires. Arc fault detection device is an active electronic device which operation is typically based on measurement of low and high frequency characteristics of the current passing through. Based on measured current characteristics and the knowledge of the arcing unique deviations in current, arc fault detection device detects possible arcing and disconnects the protected circuit. Arc fault detection device as an active electronic device is a potential source and victim of electromagnetic interference. Electromagnetic compatibility requirements are especially very demanding in military applications where low emission levels and high immunity levels are required. This article presents test results from electromagnetic compatibility testing of five different commercial arc fault detection devices against military standard requirements and analyses the suitability of the arc fault detection devices in military electromagnetic environment.

Reliable low power NoC interconnect

Information communicated through Network on Chip (NoC) in System on Chip (SoC) is highly prone to different sources of noise, like coupling, radiation and electromagnetic interference. The outcome is multi-bit errors, which can either be random or burst. As the demand for reliable NoC increases, optimal error correcting coding techniques become imperative for SoC and various multi-core and many-core architectures. A novel Multi-bit Error Correcting Coding with Reduced Link Bandwidth (MECCRLB) is proposed to achieve reliable data transmission through NoC. The proposed technique corrects burst error of four bits or random error of eleven bits or combined burst and random errors of total four bits for an input flit size of 32 bits. Analytical model based performance estimation for coding technique is extensively used in NoC. Reliability, link swing voltage and link power consumption are estimated using analytical model for the proposed MECCRLB coding technique. All the results obtained for MECCRLB coding technique are compared with Hamming product code with Type II HARQ. Estimated results show that at a probability of residual error of 10−25, the link swing voltage and the link power are reduced by 30% and 75% respectively. Results obtained from simulation followed by synthesis indicate that there is a reduction of 65%, 44%, 27%, 28% and 49% in bit overhead, NoC router area, NoC router power, codec power and codec area respectively. Furthermore, MECCRLB coding technique achieves higher error correction capability and reduces the need for retransmission. This signifies that the proposed coding technique outperforms Hamming product code with Type II HARQ in reliability, area and power.

Perioperative management of cardiac rhythm assist devices in ambulatory surgery and nonoperating room anesthesia.

Patients with cardiac implantable electronic devices (CIEDs) frequently undergo various surgical procedures and in the past perioperative management involved only placing magnet over the device. New programming features, development of implantable cardiac defibrillator (ICD), cardiac resynchronization therapy, and increasing complexity of the operating room equipment have led to new sources of electromagnetic interference (EMI). A comprehensive understanding of the CIED is necessary to provide a timely and optimal care to the patients. Technological advancements and direct implantation of the transvenous implantable cardiac defibrillators into the heart have led to less clear lines between the pacemakers and the ICD. Subcutaneous ICD as well as the leadless transcatheter deployed intracardiac pacemaker development has complicated the issue further. Rapidly developing technologies and increasing number of patients with these devices coming for noncardiac surgeries necessitate continuous education of the anesthesia team regarding perioperative management of such devices.

Modeling and Simulation of Electromagnetic Interference in Power Distribution Networks: Implications for Grid Stability

The subjects of this study are the modeling and simulation of electromagnetic interference (EMI) in power distribution networks and its consequences for grid stability. The key goals are to find the sources of EMI, assess how they affect grid performance, and create mitigation plans. A thorough study of research articles and literature on EMI modeling, simulation methods, and grid stability assessment is part of the methodology. Important discoveries emphasize the various origins and traits of electromagnetic interference (EMI), how it affects voltage control, frequency stability, and power quality, and how to mitigate and improve grid resilience. The policy implications emphasize the significance of standards, research projects, and regulatory frameworks in tackling EMI issues and guaranteeing the dependability of distribution networks. Stakeholders can ensure a consistent and adequate supply of energy to consumers by strengthening the resilience of power distribution networks and including electromagnetic interference (EMI) considerations in design, planning, and operational procedures.

Impact evaluation of conducted UWB transients on loads in power-line networks

Abstract. Nowadays, faced with the ever-increasing dependence on diverse electronic devices and systems, the proliferation of potential electromagnetic interference (EMI) becomes a critical threat for reliable operation. A typical issue is the electronics working reliably in power-line networks when exposed to electromagnetic environment. In this paper, we consider a conducted ultra-wideband (UWB) disturbance, as an example of intentional electromagnetic interference (IEMI) source, and perform the impact evaluation at the loads in a network. With the aid of fast Fourier transform (FFT), the UWB transient is characterized in the frequency domain. Based on a modified Baum–Liu–Tesche (BLT) method, the EMI received at the loads, with complex impedance, is computed. Through inverse FFT (IFFT), we obtain time-domain responses of the loads. To evaluate the impact on loads, we employ five common, but important quantifiers, i.e., time-domain peak, total signal energy, peak signal power, peak time rate of change and peak time integral of the pulse. Moreover, to perform a comprehensive analysis, we also investigate the effects of the attributes (capacitive, resistive, or inductive) of other loads connected to the network, the rise time and pulse width of the UWB transient, and the lengths of power lines. It is seen that, for the loads distributed in a network, the impact evaluation of IEMI should be based on the characteristics of the IEMI source, and the network features, such as load impedances, layout, and characteristics of cables.

High-Frequency EMI Attenuation at Source With the Auxiliary Commutated Pole Inverter

Fast-switching power converters are a key enabling technology for the more electric aircraft (MEA), but the generated electromagnetic interference (EMI) poses significant challenges to the electrification effort. To meet the stringent aerospace EMI standards, passive filters are commonly employed, despite the weight and size constraints imposed by the MEA. Alternatively, the EMI source, i.e., the high $dv\text{/} dt$ and $di\text{/} dt$ slew rates, can be addressed through waveform-shaping techniques. For example, while most soft-switching converters can reduce switching loss, they do so by switching the semiconductor devices in a slower and smoother manner, resulting in the attenuation of high-frequency harmonics. This paper examines the auxiliary commutated pole inverter (ACPI) topology, and its first contribution is the attenuation of the high-frequency content of its EMI source, that is, the output voltage, in a predictable manner, through the active control of the resonant circuit. This is achieved by first, discussing the time-domain characteristics of trapezoidal and S-shaped pulse-trains that lead to attenuated high-frequency harmonic content, and second, by analyzing the equivalent LC circuit of the ACPI. The design of the inverter is then focused on the active control of the resonant parameters, for a predetermined and enhanced output voltage high-frequency response. The second contribution of this paper is the comparison of the EMI performance of hard switching and of three soft-switching modes, fixed-timing control, variable-timing control, and capacitive turn- off s, and how this informs important metrics such as power efficiency, current stress, and implementation complexity. Finally, the third contribution is on the trade-offs that arise when the primary design goal is enhanced EMI performance as opposed to switching loss reduction. A 5-kW, 3-phase ACPI prototype is used for validating the high-frequency content attenuation at source. It is shown that the ACPI can achieve a 37 dB harmonic attenuation of its output voltage at 4 MHz, compared to a hard-switched inverter.

Cross Layer Optimization for ZigBee-Based Transmission Line Monitoring and Data Collection

A hybrid network architecture comprised of wireless sensor networks and cellular network is considered to monitor the high voltage transmission lines (HVTL). Corona noise is one of the sources of electromagnetic interference in HVTL. Automatic repeat request (ARQ) is utilized to increase the system reliability and to reduce the errors due to impulsive Corona noise. By using ARQ, link reliability is increased at the expense of communication delay. In this paper, the objective is to find the optimum location of ZigBee gateways such that reliability and latency constraints are satisfied. A cross-layer optimization technique is used to illustrate the effects of physical and MAC layer parameters on the QoS of the data collection.

A High-PSR EMI-Resistant NMOS-Only Voltage Reference Using Zero- $V_T$ Active Loads

Electromagnetic interference (EMI) disturbances coupled in the power supply of voltage and current references can severely degrade their performance, due to its finite power supply rejection (PSR). The design of a 90-dB PSR 4-dBm EMI-resistant NMOS-only voltage reference is herein presented. The voltage reference is designed based on the zero-temperature-coefficient transistor operating point. The high PSR is obtained using zero- $V_{T}$ transistors as active loads in the open and feedback loop of the circuit. Two versions, using standard $V_{T}$ and low-power $V_{T}$ transistors, were designed in a 130-nm CMOS process. Both are designed using the same thermal compensation principle. The circuits occupy 0.014 and 0.006 mm $^{2}$ of silicon area while consuming around 1.15 and 0.156 $\mu$ W at 27 $^\circ$ C, respectively. Postlayout simulations present a reference voltage of 206 and 450 mV with an average temperature coefficient of 321 and 86 ppm/ $^\circ$ C (1000 samples), under a temperature range from $-$ 55 to 125 $^\circ$ C. An EMI source of 4 dBm (1 $\text{V}_{\text{pp}}$ ) injected in the power supply, according to the direct power injection standard, yields $-$ 0.17% and $-$ 0.1 ${\%}$ of the maximum dc shift and 822 and 950 $\mu \text{V}_{\text{pp}}$ of the maximum peak-to-peak ripple for the standard $V_{T}$ and low-power $V_{T}$ implementations, respectively.