Conducted EMI Noise Prediction in DC Converter System for Electric Vehicle Application

2013 ◽  
Vol 325-326 ◽  
pp. 486-489 ◽  
Author(s):  
Zong Yu An ◽  
Quan Di Wang ◽  
Ya Li Zheng
Keyword(s):  
Equivalent Circuit ◽  
Buck Converter ◽  
Experimental Measurements ◽  
Noise Prediction ◽  
Frequency Range ◽  
Complex Approach ◽  
Proposed Model ◽  
Simulation And Experiment ◽  
Lumped Parameters ◽  
Conducted Emi

In this paper, common mode (CM) conducted perturbations are predicted and compared with experiments in a full-bridge transformer-isolated buck converter system, thanks to a complex approach based on experimental measurements and on the modeling of the complete equivalent circuit. Its different part are considered and represented by a circuit of lumped parameters. Simulation and experiment of CM emission in the conducted frequency range (150 kHz-30 MHz) are compared. It is shown that the CM emission in the system can be calculated by the proposed model, and experiment has successfully confirmed this approach.

scholarly journals An Improved Analytical Model for Crosstalk of SiC MOSFET in a Bridge-Arm Configuration

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 683
Author(s):  
Dakang Yuan ◽  
Yiming Zhang ◽  
Xuhong Wang
Keyword(s):  
Analytical Model ◽  
Good Accuracy ◽  
Experimental Measurements ◽  
Switching Speed ◽  
Fast Switching ◽  
Proposed Model ◽  
Oscillation Process ◽  
Simulation And Experiment ◽  
High Switching Speed ◽  
Voltage Switching

SiC MOSFETs have an excellent characteristic of high switching speed, which can improve the efficiency and power density of converters significantly. However, the fast switching processes of SiC MOSFETs cause serious crosstalk problems in bridge-arm configurations, which restricts the devices’ performances. This paper presents a detailed and accurate improved crosstalk analytical model, which takes into account the nonlinear capacitances, the parasitic inductances, the reverse recovery characteristics of the anti-parallel diodes, and the nonlinear voltage switching and damping oscillation process. The novelty of the proposed model lies in the fact that under the condition of comprehensively considering all these non-ideal factors of the bridge-arm, the effects of multi-parasitic elements and multi-variables coupling to the crosstalk are hierarchically divided. The parasitic elements and their correlations are described in detail and the direct and indirect variables’ impacts are clearly traced. Thus, according to the different variables switching stages, the influence processes of these parasitic elements and variables can be integrated and a complete equivalent analytical model of the crosstalk process can be derived. The simulation and experiment platforms are established and a series of experimental verifications and comparisons prove that the model can replicate experimental measurements of crosstalk with good accuracy and detail.

СУБ’ЄКТ-ОРІЄНТОВАНА МОДЕЛЬ ПСИХОКОРЕКЦІЇ ГІПЕРАКТИВНОСТІ ДОШКІЛЬНИКІВ

1970 ◽  
Vol 7 (1) ◽  
pp. 70-79
Author(s):  
Людмила Прокопів
Keyword(s):  
Psychosocial Development ◽  
Special Educational Needs ◽  
Hyperactivity Disorder ◽  
Complex Approach ◽  
Proposed Model ◽  
Special Programs ◽  
Developmental Impairment ◽  
The Subject ◽  
Comprehensive Programs ◽  
Theoretical Foundations

У статті визначено актуальність та необхідність розробки і впровадження сучасних комплексних програм психологічної корекції для дошкільників з гіперактивним розладом і дефіцитом уваги (ГРДУ). Підкреслено неможливість надання ефективної допомоги дітям з ГРДУ без урахування їх особливих потреб, пов’язаних з освітою. Обґрунтовано теоретичні засади суб’єкт-орієнтованої моделі психокорекції гіперактивності дошкільників шляхом синтезу патогенетичного і психолого-педагогічного підходів на базі принципу інтегральної суб’єктності З. С. Карпенко. Запропонована модель психокорекції гіперактивності пояснює гальмування і деформацію психосоціального розвитку дошкільника затримкою розвитку його суб’єктності в сенсомоторному, атенціональному, мнемічному, афективно-конативному, мовленнєвому, комунікативному аспектах. Аргументовано необхідність здійснення комплексного підходу до психологічної корекції, виховання і навчання гіперактивних дошкільників і впровадження спеціальних програм психоедукації для батьків. The paper highlights the topicality and need for elaboration and implementation of up-to-date comprehensive programs of psychological correction for preschool children with Attention Deficit/Hyperactivity Disorder (ADHD). Failure to provide effective aid for children with ADHD without regard to their special educational needs has been underlined. Theoretical foundations of the subject-oriented model of psychocorrection of preschool children’s hyperactivity by means of synthesis of pathogenic and psychological-pedagogical approaches on the basis of Z. S. Karpenko’s principle of integral subjectivity have been validated. The proposed model of psychocorrection of hyperactivity explains developmental impairment and deformation of psychosocial development of preschoolers by a delay of their subjectivity in terms of sensomotor, attentional, mnemic, affective-conative, speech and communicative aspects. The need for actualization of a complex approach towards psychological correction, upbringing and education of hyperactive preschoolers and implementation of special programs of psychological education for parents has been reasoned.

Equivalent circuit model of eddy current damping regarding frequency-dependence with test validation

2021 ◽  
pp. 136943322110509
Author(s):  
Zhiguo Shi ◽  
Cheng Ning Loong ◽  
Jiazeng Shan
Keyword(s):  
Equivalent Circuit ◽  
Eddy Current ◽  
Dynamic Testing ◽  
Equivalent Circuit Model ◽  
Time History ◽  
Circuit Model ◽  
Theoretical Expression ◽  
Fe Model ◽  
Damping Force ◽  
Proposed Model

This study proposes an equivalent circuit model to simulate the mechanical behavior and frequency-dependent characteristic of eddy current (EC) damping, with the validations from multi-physics finite element (FE) modeling and dynamic testing. The equivalent circuit model is first presented with a theoretical expression of the EC damping force. Then, the transient analysis with an ANSYS-based FE model of an EC damper is performed. The time-history forces from the FE model are compared with that from the proposed equivalent circuit model. The favorable agreement indicates that the proposed model can simulate the nonlinear behavior of EC damping under different excitation scenarios. A noncontact and friction-free planar EC damper is designed, and its dynamic behavior is measured by employing shake table testing. The experimental observations can be reproduced by the proposed equivalent circuit model with reasonable accuracy and reliability. The proposed equivalent circuit model is compared with the classical viscous model and the higher-order fractional model using a complex EC damper simulated in ANSYS to show the advantages of the proposed model regarding model simplicity and prediction accuracy. A single-degree-of-freedom (SDOF) structure with different EC damping models is further analyzed to illustrate the need for accurate EC damping modeling.

A Patch Antenna Design for Giga Frequency Unmanned Aerial Vehicles Application

2021 ◽  
Vol 13 (1) ◽  
pp. 01-07
Author(s):  
Dr.M.D. Javeed Ahammed ◽  
Dr.G. Srinivasa Rao
Keyword(s):  
Patch Antenna ◽  
Return Loss ◽  
Surface Current ◽  
Vital Role ◽  
Frequency Range ◽  
Gain Bandwidth ◽  
Proposed Model ◽  
Major Parameter ◽  
Aerospace Technology ◽  
Conventional Models

In this paper a present time developing application is used that is a UAV Antenna in aerospace technology. These antennas play a vital role in this WIMAX technology. A patch antenna is designed such that all the dimensions should be shrinked yet efficient in radiation in comb shape and this proposed antenna is used at 4.2GHz frequency range. A CST tool is used for designing and simulating our antenna all the dimensions taken for proposed antenna are comparatively less when compared to conventional models. Low return loss, gain, bandwidth and VSWR are optimized by using this design the efficiency is also enhanced by 95% which makes our antenna suitable to the UAV WIMAX applications. Surface current is also one of the major parameter which is reduced by our proposed model.

Effect of moisture content on dielectric properties of banana leaves and peels in frequency range of 1–20 GHz

Frequenz ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Soumya Sundar Pattanayak ◽  
Soumen Biswas
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Dielectric Loss ◽  
Moisture Content ◽  
Measurement Data ◽  
Banana Peel ◽  
Frequency Range ◽  
Proposed Model ◽  
Banana Leaves ◽  
Banana Leaf

Abstract The quality of agricultural products can be remotely sensed and enhanced by determining the dielectric properties. This paper studies the dielectric properties of banana leaf and banana peel over the frequency range 1–20 GHz using the open-ended coaxial probe (OCP) method. A new curve fitting model is proposed to characterize the dielectric properties of banana leaf and banana peel. The different moisture content (MC) levels are considered for both banana leaf and banana peel samples and, their dielectric properties are characterized. Further, the banana leaf and banana peel’s measurement data are compared with the data obtained using the proposed model. In addition, Root Mean Square Error (RMSE) and R-squared (R 2) are calculated to validate the performance of the proposed model. In case of banana leaf at 68.26% MC, the dielectric constant achieves the value of R 2 and RMSE of 0.98 and 0.0648, respectively. Similarly, dielectric loss achieves the value of R 2 and RMSE of 0.88 and 0.0795, respectively. Further, for banana peel at 80.89% MC, the dielectric constant achieves the value of R 2 and RMSE of 0.99 and 0.2989, respectively. Similarly, dielectric loss achieves the value of R 2 and RMSE of 0.96 and 0.6132, respectively.

scholarly journals Noise Prediction Using Machine Learning with Measurements Analysis

2020 ◽  
Vol 10 (18) ◽  
pp. 6619
Author(s):  
Po-Jiun Wen ◽  
Chihpin Huang
Keyword(s):  
Machine Learning ◽  
Noise Exposure ◽  
Learning Model ◽  
Training Data ◽  
Coefficient Of Determination ◽  
Gradient Boosting ◽  
Noise Prediction ◽  
Time Duration ◽  
Proposed Model ◽  
The Impact

The noise prediction using machine learning is a special study that has recently received increased attention. This is particularly true in workplaces with noise pollution, which increases noise exposure for general laborers. This study attempts to analyze the noise equivalent level (Leq) at the National Synchrotron Radiation Research Center (NSRRC) facility and establish a machine learning model for noise prediction. This study utilized the gradient boosting model (GBM) as the learning model in which past noise measurement records and many other features are integrated as the proposed model makes a prediction. This study analyzed the time duration and frequency of the collected Leq and also investigated the impact of training data selection. The results presented in this paper indicate that the proposed prediction model works well in almost noise sensors and frequencies. Moreover, the model performed especially well in sensor 8 (125 Hz), which was determined to be a serious noise zone in the past noise measurements. The results also show that the root-mean-square-error (RMSE) of the predicted harmful noise was less than 1 dBA and the coefficient of determination (R2) value was greater than 0.7. That is, the working field showed a favorable noise prediction performance using the proposed method. This positive result shows the ability of the proposed approach in noise prediction, thus providing a notification to the laborer to prevent long-term exposure. In addition, the proposed model accurately predicts noise future pollution, which is essential for laborers in high-noise environments. This would keep employees healthy in avoiding noise harmful positions to prevent people from working in that environment.

scholarly journals A metasurface composed of 3-bit coding linear polarization conversion elements and its application to RCS reduction of patch antenna

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Xiangkun Kong ◽  
Qi Wang ◽  
Shunliu Jiang ◽  
Lingqi Kong ◽  
Jing Yuan ◽  
...  
Keyword(s):  
Equivalent Circuit ◽  
Linear Polarization ◽  
Patch Antenna ◽  
Polarization Conversion ◽  
Electrical Behavior ◽  
Amplitude Response ◽  
Coding Sequence ◽  
Unit Cells ◽  
Simulation And Experiment ◽  
Equivalent Circuit Models

Abstract In this paper, a metasurface composed of 3-bit coding linear polarization conversion elements and its application to RCS reduction of the patch antenna is intensively studied. At first, 3-bit coding metasurface are constructed by a sequence of eight coded unit cells, which have a similar cross-polarized reflected amplitude response and gradient reflected phase responses covering 0–2π, respectively. Equivalent circuit models of these unit cells are created to describe their electrical behavior for the two linear incident polarizations at the same time. Then, a patch antenna is integrated on the 3-bit metasurface, of which the elements are placed with a 2-dimensional linear coding sequence. The metal square ring is set around the patch antenna to protect it from the disturbance of metasurface. Both the simulation and experiment results demonstrate that the designed metasurface can primarily reduce the antenna RCS at a broadband, while the antenna performances are not degraded significantly.

Sign in / Sign up

Export Citation Format

Share Document