Electrical network dynamic models with application to modal analysis of harmonics

2018 ◽  
Vol 154 ◽  
pp. 433-443 ◽  
Author(s):  
S.L. Varricchio ◽  
S. Gomes
Keyword(s):  
Modal Analysis ◽  
Dynamic Models ◽  
Electrical Network ◽  
Network Dynamic

Dynamic Modal Analysis of a Passenger Bus: Theoretical and Numerical Studies

2021 ◽  
pp. 036119812110288
Author(s):  
Rogério Lopes ◽  
Behzad V. Farahani ◽  
Francisco Q. de Melo ◽  
Nuno V. Ramos ◽  
Pedro M. G. P. Moreira
Keyword(s):  
Modal Analysis ◽  
Environmental Sustainability ◽  
Dynamic Models ◽  
Dynamic Assessment ◽  
Elastic Behavior ◽  
Fem Modeling ◽  
Simplified Approach ◽  
Safety Standards ◽  
The Road ◽  
Deformation Models

The dynamic assessment of a passenger bus is of the highest importance when aiming at high safety standards and low emissions for environmental sustainability. This work studies the dynamic response of a bus considering its modal analysis, for which simple dynamic models were developed for fast determination of the lowest frequencies, mainly arising from the suspension flexibility. In addition, complex natural vibration modes, impossible to determine using simplified models, were calculated via finite element method (FEM) modeling. To study the tire elastic behavior, as the key link between the vehicle and the road, specific deformation models, leading to a stiffness matrix to be combined with that of the vehicle spring suspension at each wheel/axis, were developed. This study aims at proposing a set of mathematical formulations to describe the modal behavior of passenger buses in detail, which could be applicable in any other long vehicle with similar conditions. Two main factors are studied, namely the suspension and the tire deformation effect. An acceptable agreement was verified between the simplified approach and FEM model results for the evaluation of natural frequencies and associated modes.

Experimental modal analysis for dynamic models of spacecraft

1991 ◽  
Vol 14 (3) ◽  
pp. 686-688 ◽  
Author(s):  
Keiji Komatsu ◽  
Masaaki Sano ◽  
Takashi Kai ◽  
Akio Tsujihata ◽  
Hidehiko Mitsuma
Keyword(s):  
Modal Analysis ◽  
Dynamic Models ◽  
Experimental Modal Analysis

scholarly journals Initial Results of Quantification of Model Validation Results Using Modal Analysis

2020 ◽  
Author(s):  
Urmila Agrawal ◽  
Pavel Etingov ◽  
Renke Huang
Keyword(s):  
Power Systems ◽  
Modal Analysis ◽  
Model Validation ◽  
Real World ◽  
Dynamic Models ◽  
Simulated Data ◽  
Real World Data ◽  
Prony Method ◽  
System Mode ◽  
Initial Results

<div>High quality generator dynamic models are critical to reliable and accurate power systems studies and planning. With the availability of PMU measurements, measurement-based approach for model validation has gained significant prominence. Currently, the model validation results are analyzed by visually comparing real–world PMU measurements with the model-based simulated data. This paper proposes metrics to quantify the generator dynamic model validation results based on the response of generators to each system mode, which includes both local and inter-area, using modal analysis approach. The metrics provide information on the inaccuracy associated with the model in terms of the characteristics of each mode. Initial results obtained using the real-world data validates the effectiveness of the proposed metrics. In this paper, modal analysis was carried out using Prony method.</div>

Preliminary Simulation Study Combining Operational Modal Analysis and a Two Step Parameter Identification Method on 6-SPS Parallel Manipulator for Machining Purposes

2018 ◽  
Author(s):  
Kasper Ringgaard ◽  
Ole Balling
Keyword(s):  
Dynamic Response ◽  
Parameter Identification ◽  
Modal Analysis ◽  
Dynamic Models ◽  
Operational Modal Analysis ◽  
Machining Process ◽  
Mode Shapes ◽  
Attractive Alternative ◽  
Parallel Kinematic ◽  
Six Degree Of Freedom

Machining of large components, such as multi-megawatt wind turbine parts, is currently done using large expensive CNC machines. Using small parallel kinematic machines can provide an economical attractive alternative. Optimization of the conditions for a stable and accurate machining process is necessary. Knowledge of position dependent dynamic response is key when performing such optimization. This contribution is a part of current research striving towards efficient parameter identification for dynamic models of 6-SPS parallel kinematic manipulators for machining purposes. Stiffness and damping are updated for a small set of manipulator poses using Operational Modal Analysis and a two step parameter identification routine. The model obtained contains information of the dynamic response for all poses in the workspace. In this study a six degree of freedom 6-SPS model is derived and operational modal analysis experiments are simulated. The obtained modal parameters are used for parameter identification. It is concluded that the operational modal analysis performs well in estimating frequencies and mode shapes of the symmetric structure, but damping estimates are poor. Parameter identification routine performance is satisfactory, but the poor damping estimates from modal analysis causes incorrect and uncertain parameter identification.

Comparison of dynamic models for a DC railway electrical network including an AC/DC bi-directional power station

2020 ◽  
Author(s):  
Khaled Almaksour ◽  
Youssef Krim ◽  
N’guessan Kouassi ◽  
Nicolas Navarro ◽  
Bruno François ◽  
...  
Keyword(s):  
Dynamic Models ◽  
Electrical Network ◽  
Power Station

FOUNDATIONS FOR MODELING THE DYNAMICS OF GENE REGULATORY NETWORKS: A MULTILEVEL-PERSPECTIVE REVIEW

2014 ◽  
Vol 12 (01) ◽  
pp. 1330003 ◽  
Author(s):  
ISMAEL SANCHEZ-OSORIO ◽  
FERNANDO RAMOS ◽  
PEDRO MAYORGA ◽  
EDGAR DANTAN
Keyword(s):  
Single Molecule ◽  
Computational Models ◽  
Dynamic Models ◽  
Boolean Logic ◽  
System Level ◽  
Network Dynamic ◽  
Levels Of Abstraction ◽  
Promising Alternative ◽  
Functional Relationships ◽  
Gene Regulatory

A promising alternative for unraveling the principles under which the dynamic interactions among genes lead to cellular phenotypes relies on mathematical and computational models at different levels of abstraction, from the molecular level of protein-DNA interactions to the system level of functional relationships among genes. This review article presents, under a bottom–up perspective, a hierarchy of approaches to modeling gene regulatory network dynamics, from microscopic descriptions at the single-molecule level in the spatial context of an individual cell to macroscopic models providing phenomenological descriptions at the population-average level. The reviewed modeling approaches include Molecular Dynamics, Particle-Based Brownian Dynamics, the Master Equation approach, Ordinary Differential Equations, and the Boolean logic abstraction. Each of these frameworks is motivated by a particular biological context and the nature of the insight being pursued. The setting of gene network dynamic models from such frameworks involves assumptions and mathematical artifacts often ignored by the non-specialist. This article aims at providing an entry point for biologists new to the field and computer scientists not acquainted with some recent biophysically-inspired models of gene regulation. The connections promoting intuition between different abstraction levels and the role that approximations play in the modeling process are highlighted throughout the paper.

scholarly journals Initial Results of Quantification of Model Validation Results Using Modal Analysis

2020 ◽  
Author(s):  
Urmila Agrawal ◽  
Pavel Etingov ◽  
Renke Huang
Keyword(s):  
Power Systems ◽  
Modal Analysis ◽  
Model Validation ◽  
Real World ◽  
Dynamic Models ◽  
Simulated Data ◽  
Real World Data ◽  
Prony Method ◽  
System Mode ◽  
Initial Results

<div>High quality generator dynamic models are critical to reliable and accurate power systems studies and planning. With the availability of PMU measurements, measurement-based approach for model validation has gained significant prominence. Currently, the model validation results are analyzed by visually comparing real–world PMU measurements with the model-based simulated data. This paper proposes metrics to quantify the generator dynamic model validation results based on the response of generators to each system mode, which includes both local and inter-area, using modal analysis approach. The metrics provide information on the inaccuracy associated with the model in terms of the characteristics of each mode. Initial results obtained using the real-world data validates the effectiveness of the proposed metrics. In this paper, modal analysis was carried out using Prony method.</div>

Experimental Modal Analysis of Intervertebral Disc Joint Dynamics

2008 ◽  
Author(s):  
M. Maleskian ◽  
S. S. Park ◽  
C. J. Hunter
Keyword(s):  
Intervertebral Disc ◽  
Modal Analysis ◽  
Dynamic Models ◽  
Natural Frequencies ◽  
Spinal Column ◽  
Intervertebral Discs ◽  
Experimental Modal Analysis ◽  
Receptance Coupling ◽  
Joint Dynamics

The intervertebral discs provide mobility and a degree of shock absorbance to the spinal column. It has been shown that the mechanical properties of the intervertebral discs play an important role in their functionality [1, 2]. While static models of the intervertebral disc have significance, dynamic models characterize more accurately the in situ nature of the tissues. Some researchers [3] have studied dynamic disc loading from the perspective of biomedical performance and fatigue failure. Other studies have reported on the viscoelastic properties of discs under high frequency vibration [4]. However, the authors did not find any study which used experimental modal analysis (EMA) and the receptance coupling (RC) method to extract the dynamic characteristics, i.e. stiffness, damping, and natural frequencies, of the intervertebral discs.

Modal Analysis of Turbulent Flow near an Inclined Bank–Longitudinal Structure Junction

2021 ◽  
Vol 147 (3) ◽  
pp. 04020100
Author(s):  
Nasser Heydari ◽  
Panayiotis Diplas ◽  
J. Nathan Kutz ◽  
Soheil Sadeghi Eshkevari
Keyword(s):  
Turbulent Flow ◽  
Modal Analysis ◽  
Longitudinal Structure
Sign in / Sign up

Export Citation Format

Share Document