Electromagnetic Compatibility Performance Research Articles

Performance analysis of a new single-phase transformerless PV inverter structure based on a buck-boost converter

A single-phase inverter based on a buck-boost converter is increasingly used in modern power electronics, particularly in solar photovoltaic systems. Unlike traditional inverters that utilize transformers to electrically isolate the solar system from the power grid, this transformerless design enhances efficiency, reduces weight, and lowers costs. However, the absence of a transformer introduces challenges related to Electromagnetic Compatibility (EMC) and the potential for increased leakage currents, which must be carefully managed to ensure system safety and performance. In this paper, the performances of a new configuration of a single-phase transformerless PV inverter based on a dc-dc buck-boost converter is proposed and analyzed. Since it is the only switch (mosfet) in the DC-DC converter that operates at high frequency, and it is controlled by pulse width modulation (PWM) to adjust the output voltage. This allows for flexible voltage conversion, enabling the inverter to either step up (boost) or step down (buck) the input voltage as needed. Therefore, switching losses can be significantly reduced to improve efficiency and reduce electromagnetic interference of the single-phase inverter structure. In order to demonstrate the EMC performances and evaluate the leakage current of the proposed structure, an EMC model is developed under the Simscape-MATLAB/Simulink environment, this model offers an EMC analysis including the prediction of leakage current over a frequency range from 100 Hz to 2 MHz. The results clearly showed that the level of the Total harmonic distortion (THD), as well as the levels of leakage current, are below the requested EMC standards.

Lifetime reliability modeling on EMC performance of digital ICs influenced by the environmental and aging constraints: A case study

This paper aims to develop the lifetime reliability model on electromagnetic compatibility (EMC) performance of the Atmel Attiny85 microcontroller integrated circuit (IC) chip samples, depending on the observed variation of the conducted immunity to the electromagnetic interference imposed by the combined influence of various environmental and aging (i.e., thermal and electrical voltage stress) constraints. A constant-stress accelerated degradation tests plan was designed and implemented by applying different constant thermal (i.e., 70 and 110 °C) and electrical voltage (i.e., 4 and 5 V) stress magnitude levels simultaneously in various multiple stress combinations. Direct power injection (DPI) conducted immunity tests were performed in nominal condition on all the programmed device under test (DUT) samples in both the fresh and aged states at various stress time duration. The best-fit EMC degradation paths were generated using regression analysis, followed by evaluating the pseudo time-to-failure (TTF) data and estimating the unknown parameters of the developed degradation path model. The performance metrics for lifetime reliability were evaluated by combining the Weibull distribution function with the generalized Eyring accelerated life test model. The maximum likelihood estimation method was utilized to estimate the relevant reliability model parameters. The developed reliability model was found to have the capability to estimate the electromagnetic unreliability against the lifetime TTF data of all the selected DUT samples with good precision and acceptable accuracy in both nominal and aging stress conditions. It is demonstrated that the non-failure probability of the DUT samples would remain at 1 for the first 1200 h, and that, under nominal conditions, the prediction of corresponding TTF data for all of those IC samples would fluctuate between 1400 and 1600 h.

Far field radiated emissions prediction of a flyback adapter with curved cables utilizing electromagnetic simulation method

AbstractRadiated emissions (RE) testing has long been a challenge in the development of a switched mode power supply (SMPS) with respect to electromagnetic compatibility performance. Accurate far‐field RE prediction can effectively help SMPS designers reveal and understand the mechanisms of radiation generation, and reasonably suppress it. In this paper, a model for predicting the radiation from a single excitation source and a parasitic radiator for a flyback adapter are proposed after analysing the common mode voltage and current paths. Then, novel methods are proposed to predict the far‐field RE of the flyback adapter based on measurements and electromagnetic simulations. Using these methods, the 10‐m far‐field radiation of the flyback adapter under the curved cables layout is accurately predicted and verified by experiments. Then, the characteristics and influencing factors of the radiation are analysed, including the far‐field patterns, the load volume, and the sag degree of the output cable. Finally, a suppression design of the capacitor‐inductor (CL) notch filter is designed for the frequency points that are above the standard limits, and the RE are reduced to less than 30 dBµV/m from 30 to 300 MHz. The research methods proposed in this paper have good reference significance for radiation analysis and prediction of power electronic devices.

EMI challenges in modern power electronic-based converters: recent advances and mitigation techniques

The utilization of power electronic-based converters is gaining momentum across a wide spectrum of industries. However, modern power electronic converters operate at higher frequencies compared to conventional power electronic converters, which can lead to higher rates of change in voltage and current during phase switching, and thus potentially produce more severe conducted and radiated electromagnetic interference (EMI). Their electromagnetic compatibility (EMC) has become a critical research topic, and EMI in high-frequency power electronic-based converters is more complex than that in conventional converters. This review presents a comprehensive survey of recent advancements, EMI design, and analysis of modern power electronic-based converters, focusing on the sources and mechanisms of both conducted and radiated EMI, and mitigating techniques. This review also covers the impact of topology optimization, control strategy design, and packaging design on EMC performance. Addressing emerging EMI issues in modern power electronic device-based converters is essential for ensuring safe and reliable operations. Through strategic design optimization and the implementation of EMI mitigation strategies, modern converters can seamlessly be integrated into diverse applications, offering improved EMI performance as a hallmark of their versatility.

Electromagnetic Compatibility Testing Method and Application of Generators Based on Flexible Loading System

As an important part of the extended-range new-energy vehicle, the electromagnetic compatibility of the generator system will affect the overall performance of the vehicle. Therefore, it is necessary to conduct electromagnetic compatibility testing on the generator system, which includes two parts: electromagnetic emission and electromagnetic immunity. By implementing EMC testing of generators based on flexible loading equipment, we simulate the working state of the generator system during the real vehicle operation in the 3m anechoic chamber and evaluate the electromagnetic compatibility performance of the generator system. Flexible loading equipment can solve the adverse effects of large engine system volume, high noise, and exhaust emissions on the anechoic chamber environment in extended-range new-energy vehicles, and obtain real-time testing information of the generator system, achieving the standard requirements of quantifiable and evaluable test results.

Experimental study of electromagnetic disturbances in common and differential modes in a circuit based on two DC/DC boost static converter in parallel

Introduction. An electronic control and closing control at the switch (MOSFET) will allow a parallel connection of two DC/DC boost converters. The reason for paralleling converters is to increase the efficiency of the power conversion process. This means that the overall power loss on the main switches is half the power loss on the main switch of a converter. It has been proven that DC-DC converters operating in parallel have different dynamics than a single converter. In this paper, the study is based on a system of two boost converters operating in parallel under current mode control. Although two converters operating in parallel increase the efficiency of the system, if the control parameters are not chosen correctly, the system becomes unstable and starts to oscillate. Purpose of this work is to present the analysis of high frequency electromagnetic disturbances caused by the switching of power switches in DC/DC boost static converters mounted in parallel in the presence of cables. We will study the improvement of the electromagnetic compatibility performances which can be brought by the choice of a static converters for industrial use. Methods. For the study of the path of the currents in common mode and in differential mode, it was possible to evaluate experimentally the electromagnetic compatibility impact in common mode and in differential mode of two boost converters connected in parallel in an electric circuit in connection with the source through a printed circuit board of connection between the source and the load, while using the two basic methods, namely the prediction of the conducted electromagnetic interference, the temporal simulation and the frequency simulation. Results. All the obtained results are validated by experimental measurements carried out at the Djillali Liabes University Sidi-Bel-Abbes in Laboratory of Applications of Plasma, Electrostatics and Electromagnetic Compatibility (APELEC). The experimental results obtained in common mode and in differential mode at low, medium and high frequencies are compared between the parallel boost test with and without electromagnetic compatibility filter.

Combining Obsolescence and Temperature Stress to Evaluate the Immunity of Voltage Regulators to Direct Power Injection in Long-Lifespan Systems

This letter compares the electromagnetic compatibility (EMC) performance of three different voltage regulator integrated circuits (ICs) (i.e., UA78L05, L78L05, and MC78L05) developed by three different manufacturers, with similar functionality and pin compatibility, under the influence of low and high temperature stress conditions (i.e., −30 °C and +100 °C). Direct power injection (DPI) was performed on these ICs to analyze the impact of applying thermal stress on the conducted immunity to the injection of a single-tone RF disturbance signal. The DPI immunity parameters were measured and recorded in real time for an incident amplified power, while the ICs were exposed to low and high thermal stress conditions. It was demonstrated that the minimum injected power required to reach the defined failure threshold voltage criterion <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$(\pm 4$ </tex-math></inline-formula> %) varied over frequency depending on the ICs. Moreover, these functionally identical ICs showed significant evolution of their conducted immunity in all the considered temperatures, depending on their manufacturer. Input impedance curves were monitored at low, high, and nominal temperatures, showing a noticeable decline of impedance at high frequencies. Moreover, the equivalent <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$RLC$ </tex-math></inline-formula> values of the lumped elements (i.e., resistor, inductor, and capacitor) were extracted and compared at these aforementioned temperature conditions to model the power supply network impedance for the selected ICs. The immunity behavior of these ICs was further investigated by generating lookup table data from the DPI measurements.

Electromagnetic compatibility technologies based on multi-functional spoof surface plasmon polariton channels

High integration of modern microwave circuits and systems puts forward higher requirements for multi-function and electromagnetic compatibility (EMC) performance of transmission channels. In this paper, we propose two EMC technologies including the substrate integrated packaging (SIP) and tuneable wavenumber mismatching (TWM) based on multi-functional spoof surface plasmon polariton (SSPP) channels. The SIP technology can effectively improve the EMC performance of the SSPP channels in the whole frequency band by designing the packaging structure with easy fabrication and compact size; while the TWM technology can significantly suppress crosstalks in desired frequency bands by manipulating the wavenumber difference between two adjacent channels. Simulated and measured results demonstrate excellent multi-function and EMC performance of the integrated multi-functional SSPP channels by employing the two EMC technologies. The integrated multi-functional SSPP channels can realize continuous phase modulation in X-band and continuous amplitude modulation in Ku-band. The coupling coefficient of the integrated channels is about 8–10 dB lower than that of the channels without the package, and is 13–15 dB lower than that of the traditional microstrip channels in the whole X-band and Ku-band. Meanwhile, the coupling coefficient of the integrated multi-functional SSPP channels with a distance of 1/30 λ 0 can be reduced to around −30 dB in the desired narrow bands. Therefore, the proposed EMC technologies may find broad applications in highly integrated microwave circuits and systems.

Main Circuit Topology and Electromagnetic Interference of Electric Vehicle Bidirectional Charger

In order to improve the electromagnetic compatibility performance of electric vehicle bidirectional chargers, the authors propose a main circuit topology and electromagnetic interference of the electric vehicle bidirectional charger. The design adopts the parallel connection of silicon carbide (SiC) MOSFETs and completes the bidirectional charging system based on the cascade connection of dual active bridge (DAB) and three-phase four-wire inverter. This paper mainly analyzes the influence of parasitic inductance on the drive and power loop of the T0-247 packaged switch in actual use, and according to the operating characteristics of the system, different gate resistors are used to reduce switching losses and improve system efficiency. And, we explore on how to reduce the overshoot voltage through the RC absorption circuit, thereby reducing the conducted interference. The result shows the following: the primary side absorption circuit resistance is 470 Ω and the capacitor is 47 nf, the secondary side absorption circuit resistance is 40 Ω and the capacitance is 4.7 nf, and the circuit power is 5000 W. Under the same conditions, without adding the RC absorption circuit, the conducted interference on the AC side does not meet the standard, and the amount of disturbance is large. After adding a suitable RC absorption circuit, the conducted interference on the AC side reaches the required value. Conclusion. This research provides a systematic design scheme and optimization method for designing power electronic devices using SiC.

Research on EMI suppression of high frequency isolate quasi-Z-source inverter based on chaotic frequency modulation

As a new type of topology inverter, the isolated quasi-Z-source inverter is suitable for photovoltaic power generation systems because of its high efficiency in power conversion, high boost ratio and electrical isolation. By increasing the operating frequency of the inverter, the inductance and capacitance volume of the inverter can be reduced, so that the inverter has higher power density. However, high-frequency switching actions will produce a large number of current and voltage sudden changes, leading to electromagnetic interference (EMI), affecting other components or the entire system and the stable operation of the power grid. Chaotic frequency modulation is a method to reduce the electromagnetic interference level of switching converters from the source. This method using the 10-scroll chaotic signal of the even-symmetric segmented Chen system as a spread spectrum signal to broaden the electromagnetic interference noise energy spikes to the surrounding continuous frequency bands, thereby reducing the spectrum peaks and making the system has better electromagnetic compatibility performance. In this paper, the high frequency isolated quasi Z-source photovoltaic grid-connected micro-inverter is studied, and the chaotic frequency modulation technology is used to suppress the electromagnetic interference of the inverter.

Dual-Band Bandstop Filtering Cable Design Using Defected Conductor Layer With Asymmetric Spiral Structure

In this article, we present a novel dual-band bandstop filtering cable by surrounding inner wire with asymmetric bridge-connected spiral-shaped defected structure on outer conductor. The simulation results demonstrate that the proposed dual-band bandstop filtering cable can be modeled by two parallel RLC resonance circuits in cascade and the performance can be easily adjusted by changing the structural parameters. The well-designed dual-band bandstop filtering cable can be fabricated by core wire surrounding with polytetrafluoroethylene (PTFE) dielectric layer and polyimide defected conductor layer with asymmetric bridge-connected spiral-shaped defected structures. The proposed filtering cable with ten asymmetric bridge-connected spiral-shaped defected resonators on defected conductor layer has a compact size of diameter 1.66 mm and length 200 mm, and its insertion loss in experimental results is greater than 20 dB at 0.88 and 1.3 GHz. Compared with the traditional microstrip bandstop filter, the proposed dual-band bandstop filtering cable can achieve better stopband and passband performance within more compact size. In essence, it is a cable replacement technology, which can improve electromagnetic compatibility (EMC) performance at system level and equipment level, and has the potential to be widely used in wireless system.

An EMC performance improvement method for three-phase half-bridge converter drive power supply

Analyze the electromagnetic interference (EMI) of the primary circuit of the switch tube driving power in the three-phase half-bridge converter, and study how to improve the electromagnetic compatibility (EMC) performance. The high-frequency EMI source caused by high-speed switching in the three-phase half-bridge converter is analyzed and quantitatively calculated. The high-frequency conduction model of the three-phase half-bridge converter and the driving power supply is established. Through the establishment of a high-frequency model, it is pointed out that EMI sources cause three interference conduction paths to the driving power supply: conduction paths I and II between the primary circuit and the driving power supply, conduction paths III between the driving power supply, and use the high-frequency model to obtain three conduction paths Based on the equivalent high-frequency circuit of the channel and the corresponding transfer function, a general method for suppressing three kinds of interference and improving the EMC performance of the drive power is proposed based on the transfer function. The experimental results show that the interference between the driving power supplies is the direct interference. The interference can be significantly reduced by paralleling the capacitors in the ambitious power load.

A Cable Layout Optimization Method for Electronic Systems Based on Ensemble Learning and Improved Differential Evolution Algorithm

In this article, a method for solving cable layout optimization problems in electronic systems based on ensemble learning (EL) and improved differential evolution (DE) algorithm is proposed. Using this method, we produced two cable layout schemes with the considerations of the electromagnetic compatibility performance and the total length of cables. First, several different individual machine learning (ML) models for all output variables were established. On this basis, we established EL models with better performance than previous individual ML models. Then, aiming at the optimization problem presented in this article, an improved DE algorithm was proposed. On this basis, a method for solving cable layout optimization problems in electronic systems based on EL and the improved DE algorithm was proposed. Finally, the effectiveness of the proposed method was verified by two examples of electronic system cable layout optimization with different routing modes. Each example problem was solved using four different methods. The results indicate that the method proposed here outperformed existing methods.

Electromagnetic Compatibility Analysis and Optimization Design of Switching Power Supply Printed Circuit Board

Printed Circuit Board (PCB) is not only an important electrical module of information equipment, but also an important source of electromagnetic radiation. Only when PCB works normally and is compatible with other electrical equipment, the whole information equipment can work normally. Because of the complexity of PCB structure and the difficulty of modeling, the EMC (Electromagnetic Compatibility) analysis of PCB is very difficult. For this reason, Taking the widely used full bridge current double rectifier converter as an example, aiming at the electromagnetic compatibility problems caused by the PCB design of the switching power supply, this paper proposes a simulation method based on the electromagnetic field by establishing the near-field radiation model of the PCB, analyzes the areas with high radiation intensity in the PCB layout, by optimizing the layout and wiring of the PCB, the electromagnetic compatibility performance of the switching power supply is improved. The simulation results show that the near-field radiation characteristics of PCB can be predicted by introducing the electromagnetic field simulation method in the design stage, according to the characteristics of the magnetic field, the optimal design is realized, so that the EMC of the switching power supply reaches the standard, and finally the working performance of the switching power supply is improved.

Research and Optimization of Inverter Electromagnetic Compatibility System

Modern electrical and electronic equipment has increasingly higher requirements on the reliability of its performance, especially the electromagnetic compatibility of the equipment. According to the working environment of the inverter cabinet and the design requirements of the cabinet, this paper widely combines the practical experience of the project, mainly from the aspects of gaps, ventilation holes, sealing, electrical layout, etc. It puts forward measures to improve the electromagnetic compatibility performance of the cabinet structure design. It achieves the purpose of meeting the requirements of GJB151A, and effectively improves the electromagnetic compatibility of the inverter.

A NSGA-II-Based Layout Method for Cable Bundles With Branches Using Machine Learning

There are a large number of cables in complex electronic systems, and these cables are usually arranged in multiple cable bundles with branches. In the layout of the cable bundles, the total length and weight of all cables must be minimized, and the cables must be arranged in bundles as much as possible; in addition, the electromagnetic compatibility (EMC) performance of the system must be as good as possible. In response to this problem, this study proposes a layout method suitable for cable bundles with branches in complex electronic systems: first, an automatic layout method for cable bundles with branches is proposed to obtain the initial layout of the cable bundles; then, four different machine learning methods are used to establish prediction models with four outputs and eight input variables, and a fast weighted linear fusion method based on prior information and genetic algorithm is proposed to obtain a better performance fusion model; finally, a multi-objective optimization algorithm based on machine learning and non-dominated sorting genetic algorithm-II (NSGA-II) is proposed and used to optimize the layout parameters. The validation results show the effectiveness of the proposed method.

A Reduction Technique for Modeling Closely Spaced Wires Considering Proximity Effects Applied to Predict Radiated Emission From Electric Motor

Radiated emission from electric motors interferes nearby electronic devices and, thus, degrades the electromagnetic compatibility performance of the systems. Establishing a full-wave model of electric motor is crucial to full understanding of the radiated emission. Nevertheless, challenges remain in modeling large quantities of winding wires that hinders the establishment of a full-wave model. In particular, the proximity effects of closely spaced winding wires can strongly affect their radiation characteristics by changing the charge distributions on wires, which should be critically considered in the reduction modeling. In this article, the geometrical and electrical characteristics considering proximity effects are first generated by deriving the per-unit-length capacitance matrix of wires, and a four-step reduction procedure is detailed to simplify the complete wires model influenced by proximity effects. Backpropagation (BP) neural network is used for the first time to compute the geometrical characteristics of reduced wires model. Our results show that the reduced model has identical radiation characteristics with the complete model, as such it can be applied to develop a full-wave electric motor model for the prediction of radiated emissions. The validation of our technology is testified both numerically and experimentally.

Noise Radar—Overview and Recent Developments

This article describes the principles of noise radar, emphasizing the importance of its electronic counter–counter measure (electronic protection) and electromagnetic compatibility performance and reviews some noise radar demonstrators trialed by NATO Research Task Groups. We now understand how to build noise radars with performance comparable with, e.g., a low-power marine navigation radar. Furthermore, this article discusses the distinctive issues involved in verifying the performance of noise radars.

A novel full-parameter ageing modelling approach for capacitors based on complex impedance analysis

Capacitors are ubiquitous in electronic devices and play a critical role in the devices' electromagnetic compatibility performance. The ageing of capacitors, due to intrinsic degradation mechanisms and external thermal and electrical stresses, has drawn a wide attention in the reliability field. The variations of the capacitance and equivalent series resistance are typically seen as representative for the ageing of capacitors, while the other parasitic parameters are usually neglected. In this study, a new full-parameter ageing modelling approach of capacitors is proposed based on complex impedance analysis. The ageing characteristics of all the proposed 7 parameters, including all parasitic parameters, are identified by carrying out an electrical overstress accelerated ageing test.

Design and Test of Anti-EMI for Rail Trains

With the continuous improvement of the intelligence level of the rail transit system, the installation density of electrical and electronic equipment in rail trains becomes larger and larger, which causes the increasingly prominent electromagnetic interference (EMI) problem among any equipment, systems and subsystems. This paper proposes an anti-EMI design scheme for rail trains, which improves the anti-EMI capability of the entire train system from four aspects, i.e. equipment grounding, filtering, shielding and wiring. By taking Shanghai Metro Lines 4 and 6 as an example, we carried out the system implementation and testing. The test results show that the proposed scheme is verified to be effective and reliable to improve the electromagnetic compatibility (EMC) performance.