scholarly journals Stochastic Model for Preventing Blackouts

Author(s):  
Michael Sony ◽  
V. Mariappan

Power system blackouts cause huge financial losses for the society and power utilities. Two types of blackouts have been identified. One involving load loss due to transmission lines reaching its limits and other involving failures of multiple transmission lines. Technologically advanced electricity transmission networks work in a financially just manner if a high rate of availability of the transmission networks is accomplished. Keeping this concept in mind, it is imperative to conduct the examination of transmission network availability, to design reliable electrical systems. This article discusses the stochastic availability modeling and analysis in transmission lines. The same is applied to a case of GED and the results obtained are discussed with the proper conclusion.

Author(s):  
Giulio Chiribella ◽  
Hlér Kristjánsson

Shannon's theory of information was built on the assumption that the information carriers were classical systems. Its quantum counterpart, quantum Shannon theory, explores the new possibilities arising when the information carriers are quantum systems. Traditionally, quantum Shannon theory has focused on scenarios where the internal state of the information carriers is quantum, while their trajectory is classical. Here we propose a second level of quantization where both the information and its propagation in space–time is treated quantum mechanically. The framework is illustrated with a number of examples, showcasing some of the counterintuitive phenomena taking place when information travels simultaneously through multiple transmission lines.


2013 ◽  
Vol 325-326 ◽  
pp. 673-676
Author(s):  
Lian Yang ◽  
Bin Wang ◽  
Xiao Feng Li ◽  
Chuan Hu

500kV EHV transmission networks have become the main one of the national grid, carring out live working for 500kV EHV transmission lines is the objective requirements to ensure the stable operation of the grid system. This paper uses a new system to simulate and analyse the way of entering the high electric area on 500kV transmission line. The system has built the ZM1 transmission tower and line model, accurately accounted the complex gap and satety distance. The simulation results show that the system can effectively get the best secure route and determine the way to enter into the equipotential with the safety margin.


2013 ◽  
Vol 2 (1) ◽  
pp. 1
Author(s):  
T. Eudes ◽  
B. Ravelo ◽  
R. Al-Hayek

This paper presents an enlarged study about the 50-% propagation-time assessment of cascaded transmission lines (TLs). First and foremost, the accurate modeling and measurement technique of signal integrity (SI) for high-rate microelectronic interconnection is recalled. This model is based on the reduced transfer function extracted from the electromagnetic (EM) behavior of the interconnect line RLCG-parameters. So, the transfer function established takes into account both the frequency dispersion effects and the different propagation modes. In addition, the transfer function includes also the load and source impedance effects. Then, the SI analysis is proposed for high-speed digital signals through the developed model. To validate the model understudy, a prototype of microstrip interconnection with w = 500 µm and length d = 33 mm was designed, simulated, fabricated and tested. Then, comparisons between the frequency and time domain results from the model and from measurements are performed. As expected, good agreement between the S-parameters form measurements and the model proposed is obtained from DC to 8 GHz. Furthermore, a de-embedding method enabling to cancel out the connectors and the probe effects are also presented. In addition, an innovative time-domain characterization is proposed in order to validate the concept with a 2.38 Gbit/s-input data signal. Afterwards, the 50-% propagation-time assessment problem is clearly exposed. Consequently an extracting theory of this propagation-time with first order RC-circuits is presented. Finally, to show the relevance of this calculation, propagation-time simulations and an application to signal integrity issues are offered.


2020 ◽  
Author(s):  
Tatiana Výbošťoková ◽  
Michal Švanda ◽  
Zdeněk Němeček

<p>Eruptive events on the Sun interacts with the magnetosphere and can affect even the Earth-bound structures such as power transmission networks via geomagnetically induced electric currents (GICs). We quantify the geomagnetic activity by the K-index computed from local measurements of the geomagnetic field and investigate its effects on the Czech electric power grid represented as disturbances recorded in the maintenance logs of the power network operators in course of last 12 years. In data sets recording the disturbances on high and very high voltage power lines, we found a statistically significant increase of anomaly rates within tens of days around maxima of a geomagnetic activity compared to the adjacent activity minima. Moreover, we modeled GICs for two (east-west and north-south oriented) high-voltage transmission lines in the Czech Republic and found surprisingly high values of currents, in the order of tens of amperes. Based on in-situ observations, we study propagation and properties of the largest CMEs and their relation to the disturbances in the transmission networks of the Central European countries. Our results provide an evidence that GICs may affect the occurrence rate of anomalies registered on power-grid equipment even in the mid-latitude countries.</p>


Sign in / Sign up

Export Citation Format

Share Document