scholarly journals Failure Prevention and Malfunction Localization in Underground Medium Voltage Cables

Energies ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 85
Author(s):  
Igor Aizenberg ◽  
Riccardo Belardi ◽  
Marco Bindi ◽  
Francesco Grasso ◽  
Stefano Manetti ◽  
...  
Keyword(s):  
Frequency Response ◽  
Response Analysis ◽  
Electrical Parameters ◽  
Underground Cables ◽  
Medium Voltage ◽  
Analysis Technique ◽  
Catastrophic Failures ◽  
Parameter Variations ◽  
Network Operation

A smart monitoring system capable of detecting and classifying the health conditions of MV (Medium Voltage) underground cables is presented in this work. Using the analysis technique proposed here, it is possible to prevent the occurrence of catastrophic failures in medium voltage underground lines, for which it is generally difficult to realize maintenance operations and carry out punctual inspections. This prognostic method is based on Frequency Response Analysis (FRA) and can be used online during normal network operation, resulting in a minimally invasive tool. In order to obtain the good results shown in the simulation section, it is necessary to develop a lamped equivalent circuit of the network branch under consideration. The standard π-model is used in this paper to analyse sections of a medium voltage cable and the parameter variations with temperature are used to classify the state of health of the line. In fact, the variation of the electrical parameters produces a corresponding variation in the frequency response. The proposed system is based on the use of a complex neural network with feedforward architecture. It processes the frequency response, allowing the classification of the cable conditions with an accuracy higher than 90%.

scholarly journals An Effective Method to Calculate Frequency Response of Distribution Networks for PLC Applications

Electronics ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 649 ◽  
Author(s):  
Hongshan Zhao ◽  
Weitao Zhang ◽  
Yan Wang
Keyword(s):  
Frequency Response ◽  
Distribution Networks ◽  
Dynamic Changes ◽  
Binary Function ◽  
Underground Cables ◽  
Overhead Lines ◽  
Medium Voltage ◽  
Response Characteristics ◽  
Network Topologies ◽  
Propagation Matrix

Modelling and estimating power-line communication (PLC) channels are complicated issues due to the complex network topologies, various junctions, and changeable loads. This paper focuses on the frequency response characteristics (FRCs) of medium-voltage (MV) PLC networks with special consideration of two scenarios that are often neglected but generally exist. In the first scenario, the MV distribution network is of the ring topology. In the second scenario, the MV overhead lines and underground cables join at junctions, and the shields of underground cables are grounded with nonzero grounding impedances at the junctions. These conditions lead to the failure of currently popular methods to different degrees. For this reason, we developed an effective method to calculate the FRCs of distribution networks for PLC applications. With this method, the frequency responses of nodes are simply expressed as the binary function of the overall tube propagation matrix and overall node scattering matrix, which is convenient for calculations and analyses. The proposed method was validated by the agreement between the calculated and measured FRCs. The results of two test examples showed that the proposed method performed better in comparison with the traditional approximate method when nonideal grounding conditions were taken into account. The proposed method is also independent of the network topology, so it can adapt to the dynamic changes of the network structure.

Analisa Kenyamanan Kendaraan Multiguna Pedesaan Pada Kekasaran Jalan Iso 8608

2019 ◽  
Vol 8 (02) ◽  
pp. 25-30
Author(s):  
Nanda Pranandita
Keyword(s):  
Frequency Response ◽  
Vertical Movement ◽  
Simulation Software ◽  
Suspension System ◽  
Response Analysis ◽  
The Road ◽  
Road Roughness ◽  
Vehicle Suspension System ◽  
Iso 2631

The vehicle suspension system is an important part to minimize the vibration of the vehicle caused by road unevenness. The classification of the road surface in this study is based on the classification of road roughness "Good" according to ISO 8606. The analysis of passive suspension system in this research may explain the frequency response which is received by the motorists while driving. The full car model with 1 DOF riders used in this study, simulated by using the numerical simulation software. The frequency response analysis is done on the vertical movement of the driver. Based on the analysis performed, the highest acceleration of 2.375 m / s2 at a frequency of 3.258 Hz. This value indicates the condition of "Uncomfortable" based on the table of ISO 2631. This condition will cause the rider toexperience dizziness, therefore it is strongly advised motorists to avoid frequencies below 7 Hz.

scholarly journals Measurement -based electrical parameters of power transformers for Frequency Response Analysis interpretation - Part I: Core analysis

2017 ◽  
Vol 20 (K3) ◽  
pp. 5-10
Author(s):  
Khoi Dinh Anh Pham
Keyword(s):  
Frequency Response ◽  
Power Transformers ◽  
Response Analysis ◽  
Frequency Response Analysis ◽  
Frequency Range ◽  
Electrical Parameters ◽  
Efficient Tool ◽  
Frequency Dependent ◽  
New Approach ◽  
The Core

Although the standard Frequency Response Analysis (FRA) test has been approved as an efficient tool to diagnose mechanical failures in power transformers, the demand to interpret FRA traces in practical and physical way is still requested. That means physical electrical parameters of transformers should be determined reasonably based on real measurements and afterwards are applicable for the interpretation. For purpose of FRA interpretation in practical manner, electrical parameters of power transformers in a physical equivalent circuit should be determined. As a first step, the paper introduces a new approach in determining frequency dependent core impedances of a distribution transformer based on the combination of circuit analysis of a duality-based model, measurements of driving-point impedances and experimental formulas. From that, two important contributions can be drawn. Firstly, frequency dependent core impedances are ready as available components in the circuit for FRA interpretation in broad frequency range. Secondly, the core parameters could be useful indicators for detecting relevant failures in cases there is no more failure on transformer windings.

scholarly journals Measurement-based electrical parameters of power transformers for Frequency Response Analysis interpretation-Part II: Winding Part II: Winding analysis

2017 ◽  
Vol 20 (K3) ◽  
pp. 11-17
Author(s):  
Khoi Dinh Anh Pham
Keyword(s):  
Frequency Response ◽  
Diagnostic Testing ◽  
Power Transformers ◽  
Response Analysis ◽  
Frequency Response Analysis ◽  
Frequency Range ◽  
Electrical Parameters ◽  
Frequency Dependent ◽  
The Core ◽  
Zero Sequence

For a practical Frequency Response Analysis (FRA) interpretation applicable to power transformers, frequency dependent electrical parameters of the core and windings in broad frequency range should be identified through non-destructive measurements. Since the core parameters are determined in Part I, electrical parameters of windings (resistances, capacitances) and leakage paths surrounding windings (leakage/zero-sequence impedances) of a distribution transformer will be discussed in this paper. Due to the fact that most parameters associated with the windings currently can only be measured at or around power frequency through diagnostic testing methods, the practical parameter-based FRA interpretation is not possible. To deal with this problem, the paper proposes a new approach based on the combination of different measured driving-point impedances and relevant analysis of the duality-based equivalent circuit in determining frequency dependent parameters associated with transformer windings. Results show that the physical FRA interpretation can be reasonable obtained for the test transformer in low and medium frequency range.

scholarly journals Frequency response analysis technique for induction motor short circuit faults detection

2020 ◽  
Vol 11 (3) ◽  
pp. 1653
Author(s):  
A. A. Alawady ◽  
M. F. M. Yousof ◽  
N. Azis ◽  
M. A. Talib
Keyword(s):  
Frequency Response ◽  
Induction Motor ◽  
Short Circuit ◽  
Diagnostic Methods ◽  
Response Analysis ◽  
Frequency Response Analysis ◽  
Stator Windings ◽  
Analysis Technique ◽  
Three Phase ◽  
Internal Short Circuit

<p>The paper presents the description for diagnostic methods of induction motor's stator windings fault. The presented methods use Frequency Response Analysis (FRA) technique for detection of Winding Faults in Induction Motor . This method is previously reliable method for faults diagnosis and detection in many parts of transformers including transformer windings. In this paper, this method was used for motor windings faults detection. This paper presents the FRA response interpretation on internal short circuit (SC) fault at stator winding on three cases studies of different three-phase induction motors (TPIM), were analysed according to two status: healthy induction motor at normal winding status and same motor with windings shorted of main windings. A conclusion of this paper provides the interpretation of and validation the FRA response due to internal SC fault case by using NCEPRI algorithm, which is considered as one of certified statistical indicators. The proposed method in this paper had a useful result for detect and diagnosis of stator windings faults of TPIM. The applications of developed method can be used to detece the other machines types faults.</p>

Estimation and Reduction of Motor Input Surge Voltage using Frequency Response Analysis

2012 ◽  
Vol 132 (8) ◽  
pp. 630-637
Author(s):  
Toru Wakimoto ◽  
Yoshimitsu Takahashi ◽  
Norihito Kimura ◽  
Yukitoshi Narumi ◽  
Naoki Hayakawa
Keyword(s):  
Frequency Response ◽  
Response Analysis ◽  
Frequency Response Analysis
Sign in / Sign up

Export Citation Format

Share Document