Inclusion of frequency dependences into prediction model of conducted electromagnetic emissions for a VFD motor system

2021 ◽  
pp. 1-13
Author(s):  
Youpeng Huangfu ◽  
Shuhong Wang ◽  
Shuli Yin
Keyword(s):  
Prediction Model ◽  
Motor System ◽  
Synthesis Method ◽  
Measurement Data ◽  
Quantitative Prediction ◽  
Power Cable ◽  
Frequency Dependent ◽  
Variable Frequency Drive ◽  
Macro Modeling ◽  
Electromagnetic Emissions

This paper presents a quantitative prediction model of conducted electromagnetic emissions (EME) for a variable frequency drive (VFD) motor system based on the macro-modeling approach. This model relies on the effective representations of the frequency dependent characteristics of the parasitic behaviors between converter arms and heatsink, of shielded power cable, and of motor windings. The frequency dependent performances between converter arms and heatsink, and of the motor windings are obtained by processing measurement data. Then the vector fitting method (VFM) with passivity enforcement and circuit synthesis method are adopted to obtain the corresponding equivalent circuits. The equivalent circuit implementation of shielded power cable is achieved by applying a node-to-node admittance functions (NAFs) model, which considers the propagation phenomenon and frequency dependent losses accurately. The conducted EME model is compatible with commonly used transient circuit solvers since it only includes constant circuit elements. The conducted emissions of the VFD system are then evaluated by analyzing the common mode (CM) and differential mode (DM) voltages and currents.

Sound insulation of timber hollow box floors: Collection of laboratory measurement data and trend analysis

2020 ◽  
pp. 1351010X2096615
Author(s):  
Anders Homb ◽  
Simone Conta ◽  
Christoph Geyer ◽  
Niko Kumer
Keyword(s):  
Unit Area ◽  
Dynamic Stiffness ◽  
Measurement Data ◽  
Sound Insulation ◽  
Frequency Dependent ◽  
Long Span ◽  
Wide Range ◽  
Application Data ◽  
Cavity Filling ◽  
Single Number

The industrialisation of timber buildings has improved strongly in recent years. When long span is required, timber hollow-box floor elements are increasingly used due to their structural performance. The aim of this paper is to assess the acoustic performance of timber hollow-box floors, determine the governing parameters and identify the corresponding trends. We collected results from laboratory measurements covering both airborne and impact sound insulation from four different laboratories covering a wide range of application. Data include the bare floor constructions and their combination with different floating floors including both lightweight solutions and hybrid solution. We performed the analysis focusing on following parameters: element stiffness, element mass per unit area, dynamic stiffness of the resilient layer, cavity filling and floating floor material. We present the collected data both frequency-dependent and as single number quantities. General trends and features are identified in the frequency-dependent diagrams. A further detailed analysis is based on the single number quantities. It includes a general relationship between element mass per unit area and given requirements for R’W + C50-5000 and L’n,w + CI,50-2500. Furthermore, diagrams are presented illustrating the dependence of impact sound insulation numbers on the cavity filling, the dynamic stiffness of the resilient layer and the type of material used for the floating floor. The additional mass in the cavity improves both airborne and impact sound insulation by minimum 10 dB. This, combined with a floating floor, allows the fulfilment of a wide range of requirements.

Ray Acoustics Approach to Quantitative Prediction of Highway Traffic Noise

2010 ◽  
Author(s):  
Liming Dai ◽  
Huay Seen Lee
Keyword(s):  
Prediction Model ◽  
Traffic Noise ◽  
Environmental Noise ◽  
Quantitative Prediction ◽  
Highway Traffic ◽  
Noise Levels ◽  
Modeling Approach ◽  
Highway Noise

A Highway Prediction Model (HPM) using the ray acoustics modeling approach is developed in this research. The HPM model can be used to quantitatively predict the environmental noise levels on highways of different pavements. Comparison between the measured noise levels using the SPB method and predicted noise levels with the model developed shows that the prediction model established is reliable for estimating highway noise in Canada.

Performance Assessment of Turbulence Models for the Quantitative Prediction of Tip Leakage Flow in Turbomachines

2004 ◽  
Author(s):  
Gong Hee Lee ◽  
Jong Il Park ◽  
Je Hyun Baek
Keyword(s):  
Measurement Data ◽  
Axial Flow ◽  
Turbulence Models ◽  
Reynolds Stress Model ◽  
Quantitative Prediction ◽  
Leakage Flow ◽  
Compressor Cascade ◽  
Tip Leakage Flow ◽  
Production Term ◽  
Tip Leakage

It is experimentally well-known that high anisotropy of turbulent flow field, which results from the complex shear and rotation effect, is dominant inside tip leakage vortex (TLV). With all this fact, the greater part of the numerical studies to deal with TLV have used an isotropic eddy viscosity model (EVM), and their predictions showed some disagreement with the measurement data. The main objective of the present study is to show the superior ability of the Reynolds stress model (RSM), which can naturally consider the effect of system rotation on turbulence via the rotational production term, over the isotropic EVM for predicting appropriately the complex tip leakage flow in axial type of turbomachines. To achieve this aim, the results obtained from steady-state Reynolds averaged Navier-Stokes simulations based on the Spalart-Allmaras model, Renormalization Group (RNG) k-ε model and RSM are compared with the experimental data for two test configurations: a linear compressor cascade and a forward-swept axial-flow fan. This comparative study of turbulence models suggests that the RSM should be used to predict reasonably the complex tip leakage flow, especially in a rotating environment.

Regional Short-Term Earthquake Prediction Model Based on BP Neural Network

2012 ◽  
Vol 166-169 ◽  
pp. 2309-2314
Author(s):  
Wu Sheng Hu ◽  
Hao Wang ◽  
Hong Lin Nie
Keyword(s):  
Neural Network ◽  
Linear Regression ◽  
Prediction Model ◽  
Earthquake Prediction ◽  
Linear Regression Analysis ◽  
Earthquake Magnitude ◽  
Quantitative Prediction ◽  
Earthquake Parameters ◽  
Advantages And Disadvantages ◽  
Model Based

A method which gives the quantitative prediction for earthquake magnitude is proposed in this paper. By this method, after calculating the earthquake parameters and the astronomical time-varying parameters, an earthquake prediction model can be established to gives the quantitative prediction for earthquake magnitude in the future prediction period. In this research, the research object was the experimental areas, the prediction period was 6 months, and Linear Regression analysis and conventional BP (Back Propagation) Neural Network were used respectively in prediction. Through backtracking test, the RMSEs(root mean square error) of earthquake magnitude prediction are ±0.78 ML and ±0.61 ML. Then after summarizing the advantages and disadvantages of the two methods, an integrated model based on linear regression and neural network was proposed. Through backtracking test, the RMSE of earthquake magnitude prediction reaches ± 0.41 ML, results improving significantly.

scholarly journals 3D Modeling and Volume Estimation of Riverbed Layers Based on Sub Bottom Profiler Measurement Data

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Nurkhalis Rahili Rahili ◽  
Bambang Kun Cahyono
Keyword(s):  
Travel Time ◽  
Depth Profile ◽  
Oil And Gas ◽  
Measurement Data ◽  
Volume Estimation ◽  
Power Cable ◽  
Sediment Layer ◽  
Test Results ◽  
Human Beings ◽  
Depth Data

The river is one of the transportation routes for human beings, as well as the pipelines for oil and gas distribution, or as power cable lines and communications networks. In order to not disturb the pipe or cable due to the activity of the ship through the river, it is necessary to study the sediment from the river. This study aims to determine the type of sediment, the thickness of the sediment, the depth of sediment, and volume of the sediment itself. It can be done with acoustic measurements.The measurement of the acoustic survey in this activity uses a sub bottom profiler Strata Box HD type Chirp. By using this tool, it can obtain sediment layer up to a certain depth. The result of the measurement will be interpreted to obtain the travel time of the acoustic wave as it reflected on the sediment layer. The travel time than processed and corrected with the tidal measurement data which made over 14 days to obtain the actual depth value from the result with the sub bottom profiler. The depth data then were quality tested based on reference IHO SP-44 2008 at order 1a.This activity produces a 3D model of river layer, depth profile and sediment layer volume estimation. The result of the quality tested obtained corrected depth data has met the established standards of order 1a IHO SP-44 2008. Using a 95% confidence level, the test results in the first layer is 0.271 m with an error tolerance at 0.510 m. For the second layer has a data quality test results 0.491 m with a tolerance at 0.521 m. The result of depth profile is a long section and cross section. The long section indicates that in the deflection of the river area there is a steep decline compared to the area before and after the river deflection. In addition, the river deflection area has a thinner sedimentary layer. The volume estimation of sediment layers obtained in the area of the activity is 4932752.739 m3.

scholarly journals Distribution Map of Frost Resistance for Cement-Based Materials Based on Pore Structure Change

Materials ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2509
Author(s):  
Nguyen Xuan Quy ◽  
Takumi Noguchi ◽  
Seunghyun Na ◽  
Jihoon Kim ◽  
Yukio Hama
Keyword(s):  
Prediction Model ◽  
Pore Structure ◽  
Frost Resistance ◽  
Frost Damage ◽  
Structure Change ◽  
Quantitative Prediction ◽  
Weather Data ◽  
Distribution Map ◽  
Cement Based Materials ◽  
Damage Risk

This paper presents a prediction method and mathematical model based on experimental results for the change in pore structure of cement-based materials due to environmental conditions. It focuses on frost damage risk to cement-based materials such as mortar. Mortar specimens are prepared using water, ordinary Portland cement, and sand and the pore structure is evaluated using mercury intrusion porosimetry. New formulas are proposed to describe the relationship between the pore structure change and the modified maturity and to predict the durability factor. A quantitative prediction model is established from a modified maturity function considering the influences of environmental factors like temperature and relative humidity. With this model, the frost resistance of cement-based materials can be predicted based on weather data. Using the prediction model and climate data, a new distribution map of frost damage risk is created. It is found that summer weather significantly affects frost resistance, owing to the change in pore structure of cement-based mortar. The model provides a valuable tool for predicting frost damage risk based on weather data and is significant for further research.

Porosity Parameters Quantitatively Predicted of Ultra-Low Permeability Reservoir in Hejiaji Area

2015 ◽  
Vol 1092-1093 ◽  
pp. 1440-1443
Author(s):  
Wei Huang ◽  
Xiao Li Zhang ◽  
Xi Zheng ◽  
Gao Run Zhong
Keyword(s):  
Prediction Model ◽  
Effective Porosity ◽  
Quantitative Prediction ◽  
Low Permeability ◽  
Core Analysis ◽  
Response Characteristics ◽  
The Core ◽  
Point Analysis ◽  
Set Up ◽  
Interpretation Model

Using the acoustictime logging data to establish reasonable and effective porosity parameter quantitative prediction model, can predict quality reservoir and favorable petroliferous province. Chang 6 formation in Hejiaji area is taken as an example to studing the reservoir physical properties and logging response characteristics, and the acoustictime logging and core analysis porosity are used to set up porosity logging interpretation model, then acculate porosity according to the model. The results show that after the core place treatment, the porosity quantitative prediction model established by acoustictime and layer point analysis porosity has high precision. To verify the porosity logging interpretation model of the calculated porosity and core analysis porosity, the application effect is good.

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