scholarly journals A Topology-Based Approach to Improve Vehicle-Level Electromagnetic Radiation

Electronics ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 364 ◽  
Author(s):  
Cunxue Wu ◽  
Feng Gao ◽  
Hanzhe Dai ◽  
Zilong Wang
Keyword(s):  
Complex System ◽  
Electromagnetic Radiation ◽  
Electric Vehicle ◽  
Electromagnetic Compatibility ◽  
Electromagnetic Coupling ◽  
Low Frequency ◽  
Experimental Results ◽  
Analysis Method ◽  
Network Parameters ◽  
Radiated Emissions

The popularity of the electric vehicle (EV) brings us many challenges of electromagnetic compatibility (EMC). Automotive manufacturers are obliged to keep their products in compliance with EMC regulations. However, the EV is a complex system composed of various electromagnetic interferences (EMI), sensitive equipment and complicated coupling paths, which pose great challenges to the efficient troubleshooting of EMC problems. This paper presents an electromagnetic topology (EMT) based model and analysis method for vehicle-level EMI prediction, which decomposes an EV into multi-subsystems and transforms electromagnetic coupling paths into network parameters. This way, each part could be modelled separately with different technologies and vehicle-level EMI was able to be predicted by algebra calculations. The effectiveness of the proposed method was validated by comparing predicted vehicle-radiated emissions at low frequency with experimental results, and application to the troubleshooting of emission problems.

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

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Feng Gao ◽  
Chengkai Ye ◽  
Zilong Wang ◽  
Xu Li
Keyword(s):  
Numerical Analysis ◽  
Numerical Method ◽  
Electric Vehicle ◽  
Network Theory ◽  
Electromagnetic Interference ◽  
Low Frequency ◽  
Electronic Component ◽  
Radiated Emissions ◽  
Multiport Network ◽  
Radiated Emission

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.

scholarly journals ELECTROMAGNETIC COMPATIBILITY TESTING OF ELECTRIC VEHICLES AND THEIR CHARGERS

2020 ◽  
Vol 10 (3) ◽  
pp. 70-73
Author(s):  
Aleksander Chudy ◽  
Henryka Danuta Stryczewska
Keyword(s):  
United Nations ◽  
Electric Vehicle ◽  
Electric Vehicles ◽  
Electromagnetic Compatibility ◽  
United Nations Economic Commission ◽  
Electric Vehicle Charging ◽  
Economic Commission ◽  
Radiated Emissions ◽  
Charging Stations ◽  
Current Standards

The article presents the latest information about electromagnetic compatibility testing of electric vehicles, on-board chargers and electric vehicle charging stations with a consideration of current standards and Regulation No. 10 of the United Nations Economic Commission for Europe (UNECE). The aspects of immunity, conducted and radiated emissions were taken into account.

GENERATION AND PROPERTIES OF INFRARED RADIATION

2019 ◽  
Vol 6 (2) ◽  
pp. 101-137
Author(s):  
RUSTAM KHAKIMOVICH RAKHIMOV
Keyword(s):  
Electromagnetic Radiation ◽  
Infrared Radiation ◽  
Radiation Spectrum ◽  
Laws Of Nature ◽  
Primary Source ◽  
Ceramic Materials ◽  
Experimental Results ◽  
Ir Radiation ◽  
Scattering Of Light

The article presents the main basic laws of nature and modern theories of the nature of electromagnetic radiation, its generation, characteristics, and laws of reflection, absorption and scattering of light. The principle of transformation of the radiation spectrum of the primary source using the developed ceramic materials are shown, as well as experimental results of the interaction of IR radiation with matter and various mechanisms of influence on various objects and processes are described.

scholarly journals A Multi-Mode Broadband Vibration Energy Harvester Composed of Symmetrically Distributed U-Shaped Cantilever Beams

Micromachines ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 203
Author(s):  
Xiaohua Huang ◽  
Cheng Zhang ◽  
Keren Dai
Keyword(s):  
Energy Harvester ◽  
Low Frequency ◽  
Experimental Results ◽  
Vibration Energy ◽  
Cantilever Beams ◽  
Resonant Frequencies ◽  
Promising Alternative ◽  
Piezoelectric Energy ◽  
Straight Beam ◽  
Resonance Frequencies

Using the piezoelectric effect to harvest energy from surrounding vibrations is a promising alternative solution for powering small electronic devices such as wireless sensors and portable devices. A conventional piezoelectric energy harvester (PEH) can only efficiently collect energy within a small range around the resonance frequency. To realize broadband vibration energy harvesting, the idea of multiple-degrees-of-freedom (DOF) PEH to realize multiple resonant frequencies within a certain range has been recently proposed and some preliminary research has validated its feasibility. Therefore, this paper proposed a multi-DOF wideband PEH based on the frequency interval shortening mechanism to realize five resonance frequencies close enough to each other. The PEH consists of five tip masses, two U-shaped cantilever beams and a straight beam, and tuning of the resonance frequencies is realized by specific parameter design. The electrical characteristics of the PEH are analyzed by simulation and experiment, validating that the PEH can effectively expand the operating bandwidth and collect vibration energy in the low frequency. Experimental results show that the PEH has five low-frequency resonant frequencies, which are 13, 15, 18, 21 and 24 Hz; under the action of 0.5 g acceleration, the maximum output power is 52.2, 49.4, 61.3, 39.2 and 32.1 μW, respectively. In view of the difference between the simulation and the experimental results, this paper conducted an error analysis and revealed that the material parameters and parasitic capacitance are important factors that affect the simulation results. Based on the analysis, the simulation is improved for better agreement with experiments.

Analytical Solution for Rotational Rub-Impact Plate Under Thermal Shock

2016 ◽  
Vol 32 (3) ◽  
pp. 297-311
Author(s):  
T.-Y. Zhao ◽  
H.-Q. Yuan ◽  
B.-B. Li ◽  
Z.-J. Li ◽  
L.-M. Liu
Keyword(s):  
Thermal Shock ◽  
High Frequency ◽  
Equations Of Motion ◽  
Low Frequency ◽  
Cantilever Plate ◽  
Analysis Method ◽  
Multiple Frequency ◽  
Width Direction ◽  
Blade Tip ◽  
High Frequency Vibrations

AbstractThe analysis method is developed to obtain dynamic characteristics of the rotating cantilever plate with thermal shock and tip-rub. Based on the variational principle, equations of motion are derived considering the differences between rubbing forces in the width direction of the plate. The transverse deformation is decomposed into quasi-static deformation of the cantilever plate with thermal shock and dynamic deformation of the rubbing plate under thermal shock. Then deformations are obtained through the calculation of modal characteristics of rotating cantilever plate and temperature distribution function. Special attention is paid to the influence of tip-rub and thermal shock on the plate. The results show that tip-rub has the characteristics of multiple frequency vibrations, and high frequency vibrations are significant. On the contrary, thermal shock shows the low frequency vibrations. The thermal shock makes the rubbing plate gradually change into low frequency vibrations. Because rub-induced vibrations are more complicated than those caused by thermal shock, tip-rub is easier to result in the destruction of the blade. The increasing friction coefficient intensifies vibrations of the rubbing plate. Minimizing friction coefficients can be an effective way to reduce rub-induced damage through reducing the surface roughness between the blade tip and the inner surface of the casing.

Effect of Dynamic Soft Elasticity on Vibration of Embedded Nematic Elastomer Timoshenko Beams

2018 ◽  
Vol 10 (05) ◽  
pp. 1850058 ◽  
Author(s):  
Dong Zhao ◽  
Ying Liu
Keyword(s):  
Low Frequency ◽  
Beam Theory ◽  
Timoshenko Beams ◽  
Analysis Method ◽  
Anisotropic Parameter ◽  
Nematic Elastomer ◽  
Dissipation Mechanism ◽  
Viscous Media ◽  
Complex Modal Analysis ◽  
Soft Elasticity

This paper addresses the transverse vibration of a nematic elastomer (NE) beam embedded in soft viscoelastic surroundings with the aim to clarify a new dissipation mechanism caused by dynamic soft elasticity of this soft material. Based on the viscoelasticity theory of NEs in low-frequency limit and the Timoshenko beam theory, the governing equation of motion is derived by using the Hamilton principle and energy method, and is solved by the complex modal analysis method. The dependence of vibration property on the intrinsic parameters of NEs (director rotation time, rubber relaxation time, anisotropic parameter) and foundation (spring, shear and damping constants) are discussed in detail. The results show that dynamic soft elasticity leads to anomalous anisotropy of energy transfer and attenuation. The relative stiffer foundation would restraint the rubber dissipation of viscoelastic beams, but has less influence on the director rotation dissipation, which is particular for NE beams. This study would provide a useful guidance in the dynamic design of NE apparatus embedded in soft viscous media.

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