scholarly journals Modeling of Time of Arrival Method for Lightning Locating Systems

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Saeed Vahabi-Mashak ◽  
Zulkurnain Abdul-Malek ◽  
Kamyar Mehranzamir ◽  
Hadi Nabipour-Afrouzi ◽  
Behnam Salimi ◽  
...  
Keyword(s):  
Measuring Equipment ◽  
Measuring System ◽  
Time Of Arrival ◽  
Lightning Flash ◽  
Broadband Antennas ◽  
Single Station ◽  
Cloud To Ground Lightning ◽  
Mathematical Equations ◽  
Shape Distance ◽  
Improved Accuracy

Various methods are used to locate cloud-to-ground lightning flashes. Even though a higher cost is incurred, a network of sensor stations is preferable to a single station due to the improved accuracy. For a single station measuring system, the accuracy of its analyses is mostly based on the chosen mathematical equations which can be solved in either linear or nonlinear mode. The sensitivity of the measuring equipment used is also particularly significant. This paper concentrates on the modelling of time of arrival (TOA) technique for locating a lightning flash by utilizing three broadband antennas. Consequently, by employing the developed model, the influences of geometric parameters on the accuracy of the model are evaluated. Therefore, a Matlab based simulation of the measuring system is developed. In the developed codes, randomly located lightning flash with its corresponding electromagnetic radiation was modelled. Results show that parameters such as lightning path shape, distance of the leader, and leader location can directly affect the accuracy of the TOA technique for extracting the azimuth and elevation.

Localised Single-Station Lightning Detection by Using TOA Method

2013 ◽  
Vol 64 (4) ◽  
Author(s):  
Behnam Salimi ◽  
Zulkurnain Abdul-Malek ◽  
Kamyar Mehranzamir ◽  
Saeed Vahabi Mashak ◽  
Hadi Nabipour Afrouzi
Keyword(s):  
Radiation Source ◽  
Detection System ◽  
Linear Equations ◽  
Lightning Strike ◽  
Time Of Arrival ◽  
Lightning Detection ◽  
Single Station ◽  
Mathematical Equations ◽  
Non Linear Equations

Lightning is an electrical discharge during storms that can be monitored continuously from certain distances. It can be either within clouds (intra cloud), or between clouds and the ground (cloud-ground). There are various techniques used nowadays to locate lightning, and to determine various parameters produced from lightning. Each technique provides its own claimed performances. This paper attempts to provide instantaneous detection of lightning strike lightning location using the Time of Arrival (TOA) method of a single detection station (comprises of four antennas). It also models the whole detection system using suitable mathematical equations so as to give some understanding on the differences between the measured and calculated (theoretical) results. The measurement system is based on the application of mathematical and geometrical formulas. Several parameters such as the distance from the radiation source to the station and the lightning path are significant in influencing the accuracy of the results (elevation and azimuth angles). The role of each parameter is examined in detail using Matlab. This study solved the resultant non-linear equations by Newton-Raphson techniques. Methods to determine the radiation source which include the exact coordinate of a given radiation source in 3-dimensions were also developed. Further clarifications on the cause of errors in the single-station TOA method and techniques to reduce the errors are given.

Investigation of Zero Crossing Detection for First Return Stroke in Negative Cloud-to-Ground Lightning Flash

2019 ◽  
Vol 11 (3) ◽  
Author(s):  
Ahmad Idil Abd Rahman ◽  
◽  
Muhammad Akmal Bahari ◽  
Zikri Abadi Baharudin ◽  
◽  
...  
Keyword(s):  
Lightning Flash ◽  
Return Stroke ◽  
Zero Crossing ◽  
Cloud To Ground Lightning

An Isolated Winter Cloud-to-Ground Lightning Flash Causing Damage and Injury in Connecticut

1997 ◽  
Vol 78 (3) ◽  
pp. 437-441 ◽  
Author(s):  
Ronald L. Holle ◽  
Raúl E. López ◽  
Kenneth W. Howard ◽  
Kenneth L. Cummins ◽  
Mark D. Malone ◽  
...  
Keyword(s):  
Lightning Flash ◽  
Cloud To Ground Lightning

Cloud-to-Ground Lightning Flash Characteritics in Meteorogical Conditions

1997 ◽  
Author(s):  
R.B.B. Gin ◽  
O. Pinto Jr. ◽  
I.R.C.A. Pinto ◽  
O. Mendes Jr.
Keyword(s):  
Lightning Flash ◽  
Cloud To Ground Lightning

Optimal overcurrent relay coordination in distribution network based on Lightning Flash Algorithm

2018 ◽  
Vol 35 (3) ◽  
pp. 1140-1160 ◽  
Author(s):  
Mostafa Kheshti ◽  
Xiaoning Kang
Keyword(s):  
Distribution System ◽  
Distribution Network ◽  
Distribution Networks ◽  
Lightning Flash ◽  
Content Type ◽  
Lightning Strikes ◽  
Relay Coordination ◽  
Cloud To Ground Lightning ◽  
Practical Implications

Purpose Distribution network protection is a complicated problem and mal-operation of the protective relays due to false settings make the operation of the network unreliable. Besides, obtaining proper settings could be very complicated. This paper aims to discuss an innovative evolutionary Lightning Flash Algorithm (LFA) which is developed for solving the relay coordination problems in distribution networks. The proposed method is inspired from the movements of cloud to ground lightning strikes in a thunderstorm phenomenon. LFA is applied on three case study systems including ring, interconnected and radial distribution networks. The power flow analysis is performed in Digsilent Power Factory software; then the collected data are sent to MATLAB software for optimization process. The proposed algorithm provides optimum time multiplier setting and plug setting of all digital overcurrent relays in each system. The results are compared with other methods such as particle swarm optimization and genetic algorithm. The result comparisons demonstrate that the proposed LFA can successfully obtain proper relay settings in distribution networks with faster speed of convergence and lower total operation time of relays. Also, it shows the superiority and effectiveness of this method against other algorithms. Design/methodology/approach A novel LFA is designed based on the movements of cloud to ground lightning strikes in a thunderstorm. This method is used to optimally adjust the time multiplier setting and plug setting of the relays in distribution system to provide a proper coordination scheme. Findings The proposed algorithm was tested on three case study systems, and the results were compared with other methods. The results confirmed that the proposed method could optimally adjust the relay settings in the electric distribution system to provide a proper protection scheme. Practical implications The practical implications can be conducted on distribution networks. The studies provided in this paper approve the practical application of the proposed method in providing proper relay protection in real power system. Originality/value This paper proposes a new evolutionary method derived from the movements of cloud to ground lightning strikes in thunderstorm. The proposed method can be used as an optimization toolbox to solve complex optimization problems in practical engineering systems.

Elastic characteristics of isolated segments of human aortas under dynamic conditions

1959 ◽  
Vol 14 (1) ◽  
pp. 55-59 ◽  
Author(s):  
Freeman W. Cope
Keyword(s):  
Hysteresis Loop ◽  
Thoracic Aorta ◽  
Measuring Equipment ◽  
Time Lag ◽  
Measuring System ◽  
Time Lags ◽  
Descending Thoracic Aorta ◽  
System A ◽  
Sufficient Magnitude ◽  
Elastic Characteristics

When isolated segments of human descending thoracic aorta were caused to change their volume rapidly and continuously in sinusoidal fashion with pulse pressures and pulse rates maintained in the physiological range, the resulting pressure-volume curves showed slight but consistent increases in stiffness, compared to pressure-volume curves obtained on the same specimens when inflated stepwise. There was introduced into the pressure measuring system a time lag of sufficient magnitude to eliminate the hysteresis loop. The extent of hysteresis in the aorta was not determined because time lags in the aorta could not be distinguished from time lags in the measuring equipment. Submitted on September 10, 1958

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