Measuring and Analyzing Power Quality in Electric Traction Systems

2012 ◽  
Vol 2 (4) ◽  
pp. 21-42 ◽  
Author(s):  
Andrea Mariscotti
Keyword(s):  
Transmission Line ◽  
Power Quality ◽  
Real Data ◽  
Operating Conditions ◽  
Broad Sense ◽  
Multiple Sources ◽  
Three Phase ◽  
Electric Traction ◽  
Industrial Standards ◽  
Variable Operating Conditions

Power Quality phenomena in a broad sense, stationary and transient, are considered focusing on railway applications: dc and ac traction lines are considered, identifying the main sources (fixed, like substations, and moving, like vehicles), their characteristic emissions, how they propagate and combine along the traction lines and back to the three-phase ac supply lines. The analysis covers the railway standards applicable to the traction line and the industrial standards applicable to the ac feeding lines. The peculiarity of railway applications, that is the presence of moving distorting loads interconnected by a non-ideal transmission line and characterized by variable operating conditions and by the superposition of multiple sources with different dynamics, requires specific processing, analysis and visualization methods, that are addressed by means of examples based on real data.

scholarly journals Improvement of protection relay with a single phase autore-closing mechanism based on artificial neural network

2020 ◽  
Vol 11 (1) ◽  
pp. 505
Author(s):  
Zozan Saadallah Hussain ◽  
Ahmed J. Ali ◽  
Ahmed A. Allu ◽  
Rakan Khalil Antar
Keyword(s):  
Neural Network ◽  
Artificial Neural Network ◽  
Transmission Line ◽  
Circuit Breaker ◽  
Logic Gates ◽  
Operating Conditions ◽  
System Stability ◽  
Phase System ◽  
Three Phase ◽  
Artificial Neural

This paper presents a developed logical tripping scheme to improve conventional protection performance. Adaptive single pole auto reclosure (ASPAR) system is proposed that considers, automatically tripping and reclosing of a multi-shot independent pole technique of a circuit breaker at a predetermined sequence, which can be used to boost the synchronization of the power grid under the transient fault conditions. Moreover, the ASPAR can be utilized to enhance the electrical system stability and reliability at the same operating conditions. Based on the three-phase system, the Artificial neural network (ANN) in this work has been done in order to diagnose and detect healthy and faulted phases. The proposed ANN fault classifier method consists of the logic gates, router circuits, timers, and positive and negative sequence analyses circuit. In addition, it is used to give the ability to recognize a fault type, which by training on the sequence angle values and coordination of the transmission line. Three-phase overhead transmission line including the proposed ASPAR is built in MATLA \SIMULINK environment. Thus the performance ANN-fault classified is tested under different fault conditions. Simulation results show that the proposed ASPAR based on ANN is accurate and well performance. Whereas resultant tripping and reclosing signals of ASPAR are successfully provided that enhances the circuit breaker mechanism under these operating condition.

scholarly journals Implementation of MODWT on Real Time Power Quality Disturbance Signal

2020 ◽  
Vol 9 (5) ◽  
pp. 796-800
Keyword(s):  
Data Mining ◽  
Wavelet Transform ◽  
Decision Tree ◽  
Transmission Line ◽  
Power Quality ◽  
Discrete Wavelet ◽  
Fourth Level ◽  
Three Phase ◽  
Power Quality Disturbance ◽  
Detail Coefficient

Maximal overlap discrete wavelet transform (MODWT) is the upgradation of traditional wavelet transform (WT), has been employed for localization of different power quality disturbance signal (PQDS). Every signal has been break down up to fourth level to localize the disturbances. The co-efficient of MODWT have been again employed for classification. The selected indices have been obtained utilizing the detail coefficient of this variant of WT. These features are the inputs to the data mining classifier. Decision Tree (DT) have been implemented for discrimination of PQ disturbance signals. Various PQDS have been generated in noisy and noise free climate. Besides this, the aforementioned techniques is examined with three phase signals bring out from transmission line panels.

Investigations of Road Wear Caused by Studded Tires

2014 ◽  
Vol 42 (1) ◽  
pp. 2-15
Author(s):  
Johannes Gültlinger ◽  
Frank Gauterin ◽  
Christian Brandau ◽  
Jan Schlittenhard ◽  
Burkhard Wies
Keyword(s):  
Traffic Safety ◽  
Test Bench ◽  
Operating Conditions ◽  
Test Method ◽  
Analytical Models ◽  
The Road ◽  
Driving Speed ◽  
Major Factors ◽  
Tire Friction ◽  
Variable Operating Conditions

ABSTRACT The use of studded tires has been a subject of controversy from the time they came into market. While studded tires contribute to traffic safety under severe winter conditions by increasing tire friction on icy roads, they also cause damage to the road surface when running on bare roads. Consequently, one of the main challenges in studded tire development is to reduce road wear while still ensuring a good grip on ice. Therefore, a research project was initiated to gain understanding about the mechanisms and influencing parameters involved in road wear by studded tires. A test method using the institute's internal drum test bench was developed. Furthermore, mechanisms causing road wear by studded tires were derived from basic analytical models. These mechanisms were used to identify the main parameters influencing road wear by studded tires. Using experimental results obtained with the test method developed, the expected influences were verified. Vehicle driving speed and stud mass were found to be major factors influencing road wear. This can be explained by the stud impact as a dominant mechanism. By means of the test method presented, quantified and comparable data for road wear caused by studded tires under controllable conditions can be obtained. The mechanisms allow predicting the influence of tire construction and variable operating conditions on road wear.

Treatment system response to transient AOX (adsorbable organic halogen) loadings

1997 ◽  
Vol 35 (2-3) ◽  
pp. 85-91
Author(s):  
D. A. Barton ◽  
J. D. Woodruff ◽  
T. M. Bousquet ◽  
A. M. Parrish
Keyword(s):  
Paper Industry ◽  
Model Development ◽  
Operating Conditions ◽  
System Response ◽  
Additional Information ◽  
Organic Halogen ◽  
Aox Removal ◽  
Variable Operating Conditions ◽  
Plant Shutdown

If promulgated as proposed, effluent guidelines for the U.S. pulp and paper industry will impose average monthly and maximum daily numerical limits of discharged AOX (adsorbable organic halogen). At this time, it is unclear whether the maximum-day variability factor used to establish the proposed effluent guidelines will provide sufficient margin for mills to achieve compliance during periods of normal but variable operating conditions within the pulping and bleaching processes. Consequently, additional information is needed to relate transient AOX loadings with final AOX discharges. This paper presents a simplistic dynamic model of AOX decay during treatment. The model consists of hydraulic characterization of an activated sludge process and a first-order decay coefficient for AOX removal. Data for model development were acquired by frequent collection of influent and effluent samples at a bleach kraft mill during a bleach plant shutdown and startup sequence.

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