scholarly journals Multiresolution Time-Domain Scheme for Terminal Response of Two-Conductor Transmission Lines

2016 ◽  
Vol 2016 ◽  
pp. 1-15 ◽  
Author(s):  
Zongliang Tong ◽  
Lei Sun ◽  
Ying Li ◽  
Jianshu Luo
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Time Domain ◽  
Fdtd Method ◽  
Numerical Dispersion ◽  
Dispersion Property ◽  
Scaling Functions ◽  
Terminal Response ◽  
Lossy Transmission ◽  
The Stability

This paper derives a multiresolution time-domain (MRTD) scheme for the two-conductor lossless transmission line equations based on Daubechies’ scaling functions. And a method is proposed to generate the scheme at the terminal and near the terminal of the lines. The stability and numerical dispersion of this scheme are studied, and the proposed scheme shows a better dispersion property than the conventional FDTD method. Then the MRTD scheme is extended to the two-conductor lossy transmission line equations. The MRTD scheme is implemented with different basis functions for both lossless and lossy transmission lines. Numerical results show that the MRTD schemes which use the scaling functions with high vanishing moment obtain more accurate results.

Analysis of the electromagnetic wave illumination on the transmission lines with nonlinear terminations

2021 ◽  
pp. 1-11
Author(s):  
Z. Seifi ◽  
A. Ghorbani ◽  
A. Abdipour
Keyword(s):  
Transmission Lines ◽  
Time Domain ◽  
Fdtd Method ◽  
Nonlinear Boundary Conditions ◽  
Experimental Investigations ◽  
Matrix Equations ◽  
Coupling Equations ◽  
Power Detector ◽  
Em Field ◽  
The Stability

Abstract In this paper, an unconditionally stable time-domain method is proposed to investigate the external electromagnetic (EM) field illumination on the nonlinearly loaded transmission lines. In the proposed algorithm, the field to line coupling equations and linear/nonlinear boundary conditions are incorporated and expressed in a matrix form. The derived differential matrix equations are then discretized and solved using the proposed finite difference time domain (FDTD) method approach. The discretized nonlinear matrix equations are also solved by applying a globally convergent iterative method to ensure the stability of the method. Moreover, the experimental investigations are conducted using a transverse EM (TEM) cell for a single microstrip line and a power detector circuit as a nonlinearly loaded transmission line to confirm the accuracy and stability of the proposed method. With the merit of satisfactory accuracy and unconditional stability for the entire range of time steps, the presented approach would be applicable for analyzing the microwave linear/nonlinear circuits subjected to the external incident EM wave.

Study on the characteristics of secondary arc current of UHV high compensation degree TCSC line under the fine-tuning mode

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Baina He ◽  
Yadi Xie ◽  
Jingru Zhang ◽  
Nirmal-Kumar C. Nair ◽  
Xingmin He ◽  
...  
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Stability Margin ◽  
Transmission Capacity ◽  
Fine Tuning ◽  
Series Compensation ◽  
Arc Current ◽  
Compensation Device ◽  
The Stability ◽  
Recovery Voltage

Abstract In the transmission line, the series compensation device is often used to improve the transmission capacity. However, when the fixed series capacitor (FSC) is used in high compensation series compensation device, the stability margin cannot meet the requirements. Therefore, thyristor controlled series compensator (TCSC) is often installed in transmission lines to improve the transmission capacity of the line and the stability of the system. For cost considerations, the hybrid compensation mode of FSC and TCSC is often adopted. However, when a single-phase grounding fault occurs in a transmission line with increased series compensation degree, the unreasonable distribution of FSC and TCSC will lead to the excessive amplitude of secondary arc current, which is not conducive to rapid arc extinguishing. To solve this problem, this paper is based on 1000 kV Changzhi-Nanyang-Jingmen UHV series compensation transmission system, using PSCAD simulation program to established UHV series compensation simulation model, The variation law of secondary arc current and recovery voltage during operation in fine tuning mode after adding TCSC to UHV transmission line is analyzed, and the effect of increasing series compensation degree on secondary arc current and recovery voltage characteristics is studied. And analyze the secondary arc current and recovery voltage when using different FSC and TCSC series compensation degree schemes, and get the most reasonable series compensation configuration scheme. The results show that TCSC compensation is more beneficial to arc extinguishing under the same series compensation. Compared with several series compensation schemes, it is found that with the increase of the proportion of TCSC, the amplitude of secondary arc current and recovery voltage vary greatly. Considering various factors, the scheme that is more conducive to accelerating arc extinguishing is chosen.

scholarly journals Detection method based on improved faster R-CNN for pin defect in transmission lines

2021 ◽  
Vol 300 ◽  
pp. 01011
Author(s):  
Jun Wu ◽  
Sheng Cheng ◽  
Shangzhi Pan ◽  
Wei Xin ◽  
Liangjun Bai ◽  
...  
Keyword(s):  
Transmission Line ◽  
Defect Detection ◽  
Transmission Lines ◽  
False Positive Rate ◽  
Detection Algorithm ◽  
Detection Model ◽  
Positive Rate ◽  
Aerial Vehicle ◽  
The Stability ◽  
Small Targets

Defects such as insulator, pins, and counterweight in highvoltage transmission lines affect the stability of the power system. The small targets such as pins in the unmanned aerial vehicle (UAV) inspection images of transmission lines occupy a small proportion in the images and the characteristic representations are poor which results a low defect detection rate and a high false positive rate. This paper proposed a transmission line pin defect detection algorithm based on improved Faster R-CNN. First, the pre-training weights with higher matching degree are obtained based on transfer learning. And it is applied to construct defect detection model. Then, the regional proposal network is used to extract features in the model. The results of defect detection are obtained by regression calculation and classification of regional characteristics. The experimental results show that the accuracy of the pin defect detection of the transmission line reaches 81.25%

New Methodology of Fault Identifier for the Double Circuit Line on the same Tower

2014 ◽  
Vol 521 ◽  
pp. 330-333
Author(s):  
Yu Sheng Quan ◽  
En Ze Zhou ◽  
Hua Gui Chen ◽  
Xin Zhao
Keyword(s):  
Power System ◽  
Transmission Line ◽  
Transmission Lines ◽  
Social Economy ◽  
Criterion Function ◽  
Transient Fault ◽  
Permanent Fault ◽  
Overhead Transmission Line ◽  
Practical Engineering ◽  
The Stability

High voltage overhead transmission line is an important part of the power system to ensure the safe operation of the entire power system, which is of great significance. Power line fault not only has adverse effects to the social economy, and it may also affect the stability of the power system. Transmission line faults including permanent fault and transient fault are identified quickly and accurately, which has important practical engineering significance. This paper presents a method which can be used to identify the permanent fault and transient fault of double-circuit transmission line on the same tower, fault transient voltages and currents extracted from both ends of transmission lines are as a signal source which is decomposed into a series of harmonics in order to establish a criterion function, and then the transient and permanent fault can be identified based on the changes of criterion function value.

Sign in / Sign up

Export Citation Format

Share Document