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The RF desense problem in wireless products becomes serious due to faster digital signals and minimal area in print circuit boards (PCBs). This article proposes a systematic design of interleaved power transmission lines to suppress electromagnetic interference due to magnetic coupling from the power delivery system of digital circuits to RF components. It improves noise suppression by more than 20 dB, in only two-layer PCB, with one power trace and three enclosing grounds to replace the conventional power trace in the same occupied area. A general design chart of isolation improvement versus trace width, spacing, and substrate thickness is constructed. Finally, the proposed concept is verified by experiment and simulation. [ABSTRACT FROM AUTHOR]

Summary: Because of its small size, low local contrast, and much interference, the field image of fine‐grained equipment taken from power transmission line surveillance is hard to be sustained by the traditional small target detection technique, which requires the manual extraction of features, making it difficult to accurately detect micro‐fine‐grained equipment. The deep learning‐based algorithms have prospective application but require abundant data to guarantee performance and tackle the problem of foreground–background imbalance. This paper develops an effective pipeline, i.e., limited sliding network (LSNet), to detect the small and fine‐grained defects on equipment in power transmission line infrastructure. The model firstly performs the regional analysis on the entire image to determine the potential target locations. The feature extraction and classification on the potential location image blocks are further performed by the VGG‐style model for the dense target locations, and the nonmaximum suppression method is finally applied to locate the target. On the other hand, a specific training method is also developed to better deal with a wide range imbalances of positive and negative samples. The proposed method achieves the detection mean average precision (mAP) rate of 98.66% on the real datasets, while limiting the computational overhead of hardware. [ABSTRACT FROM AUTHOR]

Background and purpose: Considerable increase on the use of electronic devices increased the rate of public occupational exposure to extremely low frequency electromagnetic fields. Assessment of exposure to these fields is highly important due to potential health hazards. This study aimed at investigating the magnetic flux emission from extremely low frequency electromagnetic fields around power lines of high voltage in Neka (north of Iran) and factors affecting the magnetic flux density. Materials and methods: In this cross-sectional study, 50 sites around high voltage transmission lines were selected and the magnetic flux density was measured at four different distances from the lines. Humidity and temperature were measured in order to assess their impact on magnetic flux density. The extremely low-frequency magnetic field was measured using an electromagnetic field tester (model TES 1394). Statistical analysis was performed in SPSS V17 applying descriptive statistics and one-way ANOVA. Results: The highest average magnetic flux density was at the 400 kV power transmission line (2.11 ± 1.36 µT). The average magnetic flux density was higher in the afternoon (2.55 µT) compared with that in the morning. The average values for magnetic flux density under the pylon and between two pylons were 1.18 ± 0.75 and 2.55 ± 1.42 µT, respectively. Magnetic flux density decreased by increasing distance from the wire and the environment moisture. Conclusion: The average magnetic flux density was lower than the standards set by the international commission on non-ionizing radiation protection and American Conference of Governmental Industrial Hygienists. Hence, the health effects would be negligible.

Abstract High resistance fault poses an enormous challenge to the existing algorithms of fault detection and fault classification. In this paper, the standard deviation and accumulation method are employed to perform the fault detection and classification. It is primarily built in two stages. Firstly, the standard deviations for the measured current’s signals of the local and remote terminals is computed to extract the fault feature. Secondly, the cumulative approach is used to enlarge the fault feature to perform the high resistance fault. The proposed scheme is known as Standard Deviation Index (SDI), and it is obtained for the three phases and zero sequence. The proposed algorithm has been tested through different fault circumstances such as multiple faults locations, fault resistances, and fault inception time. Moreover, far-end faults with high-resistance, faults happened nearby the terminal, faults considering variable loading angle, sudden load change, different sampling frequency, bad signaling and a fault occurred in the presence of series compensation are also discussed. The results show that the proposed scheme performed remarkably well regarding the fault with resistance up to 1.5kΩ and can be detected within a millisecond after the fault inception. Additionally, the computational simplicity that characterizes the processes makes it more efficient and suitable for domain applications.

To meet the requirements of mechanical dimensions, climbing performance and obstacle negotiation capability of an inspection robot on the long-span transmission line, a novel inspection robot with four arms is designed by drawing on the research on human being’s climbing on a tree. Firstly, according to its kinematical characteristics we learned from human being’s tree climbing, the mechanism configuration of the robot on the transmission line is introduced and methods of overcoming two typical obstacles are planned. Then, its main structural parameters are provided, its kinematics equation is derived, and the analysis of kinematics performances such as grade ability and obstacle overcoming is carried out to verify the feasibility of the mechanism design. Finally, experiments on movement are conducted on the platform of virtual prototype. The results indicate that the robot has such features as excellent grade ability and obstacle overcoming performance.

Due to its inherent low damping, a power transmission line is prone to wind induced vibration. Vibration control is needed to suppress the aeolian vibration of the transmission-line to reduce the fatigue and to extend its service life. Though patented in 1928, more than 90 years ago, the Stockbridge damper or its variants are still commonly used for vibration suppression of conductors in modern day power transmission systems because of their advantages of simple structure, low cost, reliable operation and effective vibration suppression. This paper offers a comprehensive review of the development, modeling, analysis, and design of the Stockbridge-type dampers and their applications in Aeolian vibration control of power transmission lines. A Stock bridge-type damper is a dumbbell-shaped device that consists of a short messenger cable with two masses at the ends and a clamp at the middle to attach to a conductor. The friction among the strands in the messenger cable dissipations energy. A Stock bridge-type damper is essentially a tuned mass damper. For the modeling of a Stockbridge damper alone, the classis linear mechanics analysis, the nonlinear analysis, and finite element method (FEM) are reviewed. For the modeling of the combined damper and conductor system, this paper mainly reviews the Energy Balance Principle (EBP) that is relatively easy to use and can obtain the energy dissipated by the damper. Two important design issues, the damper parameter sensitivity analysis and damper location optimization, are discussed in this paper. This paper also briefly reviews the experimentation and fatigue related to a Stockbridge damper. In addition, this paper provides an outlook of future development, analysis, and application of Stockbridge-type dampers for conductor vibration control. [ABSTRACT FROM AUTHOR]

In this paper, a system is proposed for visualizing and analyzing icing monitoring data of power transmission lines. The distributions of temperature and humidity are visualized by two-dimensional maps with customizable map layers. The multi-dimensional monitoring data are visualized as parallel coordinates. Moreover, a prediction algorithm that is based on a hybrid deep belief network is integrated into the system for predicting the icing thickness. If the icing thickness of a certain location exceeds the threshold value, the historical meteorological data of the location can be visualized as line graphs, which helps to choose the appropriate de-icing measures. According to the experimental results, our system is capable of reflecting the statistical features of icing monitoring data with high accuracy of icing thickness prediction. [ABSTRACT FROM AUTHOR]

Copyright of Electric Power Automation Equipment / Dianli Zidonghua Shebei is the property of Electric Power Automation Equipment Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The identification of risks linked to electromagnetic compatibility (EMC) in the electric railway is a major concern in identifying EMC problems and analyzing the unintentional various external disturbing sources as well as the probability of occurrence of interference, the level of interference along the railway system. The purpose of this analysis is to determine the electromagnetic interaction coupling generated by the high voltage (HV) lines located along the railway line by analyzing the voltage induced in the signaling transmission cables such as the european rail traffic management system/european train control system (ERTMS/ETCS) through the multi-conductor transmission line (MTL) theory which may have an impact on the transmitting information. Dubanton method and approximate calculation will be applied and simulated through COMSOL Multiphysics tool in order to analyze if the protection distance and coupling conditions are respected by the railway standards. [ABSTRACT FROM AUTHOR]

The results of using a mathematical model to study advanced algorithms for the automatic load-frequency control (ALFC) system of 800 MWPower Unit 1 of the Perm TPP islanded as part of the Perm-Zakamsky energy hub from the UES of Russia are presented. To prevent long-term oscillations of power and frequency of the power unit during power surges due to the reduced capacity of the power lines, advanced ALFC algorithms are proposed and analyzed. A criterion for the activation of these algorithms is proposed, and the optimal one is chosen. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A high-voltage AC double-circuit 400 kV overhead power transmission line runs from the city of Elk (Poland) to the city of Alytus (Lithuania). This international 400 kV power transmission line is potentially one of the strongest magnetic field-generating sources in the area. This 400 kV voltage double-circuit overhead transmission line and its surroundings were analyzed using the mathematical analytical methods of superposition and reflections. This research paper includes the calculation of the numerical values of the magnetic field and its distribution. The research showed that the values of the magnetic field strength near the international 400 kV power transmission line exceed the threshold values permitted by relevant standards. This overhead power line is connected to the general (50 Hz) power system and generates a highly intense magnetic field. It is suggested that experimental trials should be undertaken in order to determine the maximum values of the magnetic field strength. For the purpose of mitigating these values, it is suggested that the height of the support bars should be increased or that any individual and commercial activities near the object under investigation should be restricted. [ABSTRACT FROM AUTHOR]

The drone‐based inspection process on power transmission lines needs to be automated due to the large scale of power facilities and the limited line of sight available to drone pilots. Through the task environment analysis, however, it was found that the steel tower structure and energized AC power conductors may cause GPS signal distortion and magnetic interference with a drone's geomagnetic sensor, respectively. These factors could seriously affect the drone's autopilot flight, at worst leading to a crash. To enable drone inspections to be performed in a safe and efficient manner, this paper presents the entire process of operating an autopilot inspection drone on the basis of GPS and GIS information in a hazardous ultrahigh voltage environment, and its application results in the field. This process includes how to measure GPS co‐ordinates of steel towers and how to generate an autopilot flight path. More specifically, the paper examines the potential problems that may occur when drones are applied to areas located in mountains and rivers where humans cannot inspect power lines due to a lack of accessibility, and proposes effective solutions to these practical issues. [ABSTRACT FROM AUTHOR]

In mountainous areas, the installation of steel towers was the major obstacle to the construction of transmission lines. In long-span cross-rope suspension (CRS) structures, the conductors are supported by hundreds-meters-long suspension cables crossing valleys instead of steel towers. Though long-span CRS is an innovative structural system, its structural performance needs to be clarified. Firstly, an assembled FE model was established based on initial deformed components for long-span cross-rope suspension structure. The wind load response of long-span cross-rope suspension structure with different lengths or number of spans was established and analyzed. Vortex-induced vibration (VIV), which was the major factor regarding fatigue and service life, and its controlling by Stockbridge damper for a long-span CRS were discussed. The numerical simulation results showed that the tensile force of the suspension cable increased with the length and number of spans of the conductor. In addition, considering the ice covering the transmission line, the interaction between the wind load and ice load induced the nonlinear lateral deformation characteristics of the conductor. Moreover, the vibration characteristics of the conductor in the long-span CRS were studied and compared with the traditional tower-line system. An analysis of the long-span CRS with a Stockbridge damper showed that additional dampers were essential for controlling the maximum dynamic bending stress of conductors at both ends.

To install a new infrastructure of a power transmission line is not only costly but also time-consuming, and it also have some harmful impact on our environment and therefore existing transmission infrastructure is important to use effectively. FACTS is a popular solution to utilize this existing power transmission system by using series compensation by means of the series capacitor to enhance the power transmission capacity as well as voltage stability. This paper explores the utilization of series capacitor applying to the power grid of Eastern part of Bangladesh. For doing this we have considered the analytical calculation of 10% to 85% compensation of that power line. As a result, we have observed that the power transfer capacity has been enhanced about 37 times and it also improve the voltage stability, when the compensation ration is 85%. We consider our calculation mathematically and represent the load curve and voltage profile by plotting in Matlab.

Electromagnetic Compatibility (EMC) disturbance produced by power transmission lines (TL) near the railway installation can generate electromagnetic coupling between the high voltage power line and the signalization cables. In this paper, the voltage induced is analyzed in the signaling system cables located along the high-speed line due to the proximity of an extra high voltage power line. An approximate and Dubanton method have been used in order to have a correct result of the mutual inductance. The proposed technique is compared with the sensitivity threshold of the railway devices in order to check if the presence near high voltage lines will not interfere with the normal operation of the railway equipment. The performance of the Electromagnetic radiation is presented through simulation results. [ABSTRACT FROM AUTHOR]

Classifying and identifying the disturbances in power transmission lines have been challenging tasks for accurate and reliable protection of power transmission line. This paper deals with the design of a Discrete Wavelet Transform (DWT) and an Artificial Neural Network (ANN) based on relay for transmission line fault classification. Applying any form of wavelet transforms produces details, which are related to high frequency components, as well as approximations, which are related to low frequency components at each level of resolution. A simulation setup is developed for collecting various phases' currents waveforms for purposes of selecting the optimal mother wavelet and the number of levels of resolutions. The Daubechies (db5) mother wavelet with one level of resolution is found to be optimal in providing adequate information in order to detect and classify transmission lines faults. The proposed approach is used to classify shunt and series faults. The proposed algorithm is tested using MATLAB/Simulink on a data collected from a typical transmission line. [ABSTRACT FROM AUTHOR]

A high-voltage AC double-circuit 400 kV overhead power transmission line runs from the city of Elk (Poland) to the city of Alytus (Lithuania). This international 400 kV power transmission line is potentially one of the strongest magnetic field-generating sources in the area. This 400 kV voltage double-circuit overhead transmission line and its surroundings were analyzed using the mathematical analytical methods of superposition and reflections. This research paper includes the calculation of the numerical values of the magnetic field and its distribution. The research showed that the values of the magnetic field strength near the international 400 kV power transmission line exceed the threshold values permitted by relevant standards. This overhead power line is connected to the general (50 Hz) power system and generates a highly intense magnetic field. It is suggested that experimental trials should be undertaken in order to determine the maximum values of the magnetic field strength. For the purpose of mitigating these values, it is suggested that the height of the support bars should be increased or that any individual and commercial activities near the object under investigation should be restricted.

In order to analyze the uplift bearing capacity of cone-cylinder foundation for transmission line in frozen soil regions, a series of reduced-scale modeling tests and numerical simulations are carried out. First, three reduced-scale cone-cylinder foundations with the same sizes, that are five times smaller than the prototype, are made and then loaded under uplift load at −5 °C, −10 °C, and −15 °C, respectively. On this basis, the foundations of nine sizes are modeled and loaded by numerical simulation. The impact of three dimension factors, including the ratio of depth to bottom width ( λ = h t / D t ), the top diameter of the cone-cylinder (d), and the bottom diameter of the cone-cylinder (D), on the uplift bearing capacity of foundations have been investigated. The results reveal that, for cone-cylinder foundation, the uplift bearing capacity is obviously affected by the freezing temperatures and the foundation sizes. The capacity is negatively correlated with the former. Whereas the order of correlation with the latter is as follows: λ, D, and d based on the comprehensive results of range and variance analysis, but none of them are the significant factors, according to the F-test. Furthermore, three failure mechanisms of frozen soil are distinguished and named T-mode, V-mode, and U-mode, respectively. Based on the above results, the bearing mechanism of cone-cylinder foundation in frozen soil is elaborated in detail.

This article considers the effects of wire breakage in networks with an insulated neutral, as well as issues related to detecting the location of such damage. The need to use means and techniques for rapidly localizing line sections with wire breakage is revealed and justified. The analysis conducted allows proposing a technique for detecting line sections with phase wire breakage in branched networks with an insulated neutral. This technique is based on analyzing voltage readings from the meters installed in the low-voltage part of transformer substations connected to the damaged network. The implementation of this technique requires using software that is integrable with available electronic supervisory control resources without installing additional equipment because it is possible to use electric counters with data transmitters installed everywhere at transformer substations as voltage meters. [ABSTRACT FROM AUTHOR]

Abstract This paper proposes a new deep learning network - RCNN4SPTL (RCNN -based Foreign Object Detection for Securing Power Transmission lines), which is suitable for detecting foreign objects on power transmission lines. The RCNN4SPTL uses RPN (Region Proposal Network) to generate aspect ratio of the region proposals to align with the size of foreign objects. The RCNN4SPTL uses an end to end training to improve its performance. Experimental results show that the RCNN4SPTL significantly improves the detection speed and recognition accuracy, compared with the original Faster RCNN. [ABSTRACT FROM AUTHOR]

Since the power transmission line (PTL) passes through the high mountain and heavy snowfall region, it is necessary to keep the stability of the PTL. In this study, PTL is modeled as the mass-spring-damper system by using multi-body dynamics analysis program. In order to analyze the dynamic behavior of PTL, a damping coefficient for a multi-body model is derived by using the free vibration test and Rayleigh damping theory. The icing cross section of the transmission line is considered by ellipse and triangle shape. The aerodynamic coefficient for each cross sections are derived by using the commercial CFD program, ANSYS Fluent. The fluctuating wind velocity is regenerated with time history by using Kaimal spectrum. Galloping simulations are performed for the elliptical and triangular iced sections by using the generated fluctuating wind velocity. There is an attack angle which showed the maximum vertical displacement according to the icing section. As a results, the triangular icing shape on the fluctuating wind velocity is more dangerous for the galloping phenomenon. This results can be available to the tower design for the power transmission line. [ABSTRACT FROM AUTHOR]

When the power transmission line (PTL) passes through a region of high mountains and heavy snowfall, maintaining the stability of the PTL and avoiding sleet jump and galloping are necessary. In this study, PTL is modeled as the mass-spring-damper system by using the multi-body dynamics analysis program, RecurDyn. The lumped mass model is compared with the finite element model based on deflection. To analyze the dynamic behavior of the PTL under icing and wind conditions, we obtained a damping coefficient for a multibody model from the free vibration test and Rayleigh damping theory. The icing cross-section of the transmission line is assumed to have ellipse and triangle shapes. The aerodynamic coefficients for each cross-section are derived by using the commercial CFD program, ANSYS Fluent. The occurrence of galloping is simulated for each shape according to the attack angle. Results indicate that the dynamic behavior of the PTL and the galloping conditions such as the icing shape, thickness, and attack angle, can be analyzed. Furthermore, the effects of each factor are evaluated. In the elliptical icing section, the effect of icing thickness is high; whereas in the triangular icing section, the wind velocity highly affects galloping. [ABSTRACT FROM AUTHOR]

In this paper, a new algorithm is proposed for faults detection and classification in the power transmission line. The key of the proposed algorithm depends on the computing of the linear regression coefficient indices (LRCIs) of the three‐phase current signals. The proposed algorithm has constructed a rule as follows: when the system is running under the health condition, the LRCIs will be equal to zero; when the system is subjected to the fault condition, the LRCIs of faulted phases will be greater than zero. Different faults circumstances, such as different inception time, different fault resistances, and different locations, have been verified. Additional scenarios such as far‐end fault with high resistance, fault occurred near the terminal, fault considering variable loading angle, and fault at the presence of noise are also discussed. For each possible scenario of faults, the proposed algorithm required only the three‐phase current measurement of the local measurement. The proposed algorithm has demonstrated a reasonable time response, where the fault condition could be detected within a few milliseconds after the fault inception. Therefore, the proposed algorithm is quite suitable for faults detection and classification in power transmission lines. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

To install a new infrastructure of a power transmission line is not only costly but also time-consuming, and it also have some harmful impact on our environment and therefore existing transmission infrastructure is important to use effectively. FACTS is a popular solution to utilize this existing power transmission system by using series compensation by means of the series capacitor to enhance the power transmission capacity as well as voltage stability. This paper explores the utilization of series capacitor applying to the power grid of Eastern part of Bangladesh. For doing this we have considered the analytical calculation of 10% to 85% compensation of that power line. As a result, we have observed that the power transfer capacity has been enhanced about 37 times and it also improve the voltage stability, when the compensation ration is 85%. We consider our calculation mathematically and represent the load curve and voltage profile by plotting in Matlab. [ABSTRACT FROM AUTHOR]

To install a new infrastructure of a power transmission line is not only costly but also time-consuming, and it also have some harmful impact on our environment and therefore existing transmission infrastructure is important to use effectively. FACTS is a popular solution to utilize this existing power transmission system by using series compensation by means of the series capacitor to enhance the power transmission capacity as well as voltage stability. This paper explores the utilization of series capacitor applying to the power grid of Eastern part of Bangladesh. For doing this we have considered the analytical calculation of 10% to 85% compensation of that power line. As a result, we have observed that the power transfer capacity has been enhanced about 37 times and it also improve the voltage stability, when the compensation ration is 85%. We consider our calculation mathematically and represent the load curve and voltage profile by plotting in Matlab. [ABSTRACT FROM AUTHOR]

Background: FMEA is one of the best known system safety techniques widely used as an identification tool. The purpose of this study was to apply FMEA method to identify and assess the risks posed by power lines in a residential area is Hasyrabad, Ahwaz. Materials and Methods: First, we identified the power line process and the equipment involved. Later, we determined the failure modes of equipment, which leads to the risk in the area studied. In order to measure the magnetic field lines, we used 3D EMF TESTER. Risks identified were scored based on the FMEA and for each case we calculated RPN. Then, with the help of SPSS software, we calculated level of risk and the cases identified were prioritized and analyzed based on the risk level. Results: The highest RPN values were associated with health risks and all risks involved in this group are at emergency conditions. It was revealed that wires (loss of privacy) and power transmission line (non-compliance with privacy standards) had highest value (RPN 360) and disconnect switch had lowest value (RPN 60). Conclusion: Due to the high risk in most cases, control measures were proposed based on the expertise in the safety-related equipment, training operators, and regulatory measures in order to reduce the level of risk.

Fast and precise location of faults in power transmission lines is essentially important for fast line restoration. Widely used fault location methods based on impedance measurement and travelling wave analysis have some drawbacks leaving a lot of room for further research. This study proposes a novel method for estimation of the location of the asymmetrical phase‐to‐ground faults that exist during line energisation. The method is based on the empirical mode decomposition and its application relies on knowing the fundamental system parameters and frequency estimation of the analysed signal. It is simple to use while providing highly accurate results for overhead lines up to 80 km length. [ABSTRACT FROM AUTHOR]

This paper captures the behavior of micropiled rafts in power transmission line tower foundations in cohesive soil, concentrating on their uplift performance whether due to the tower position along the line or under wind loading conditions. In this regard, first a number of micropiles were driven into the ground of a project site at the ParehSar power plant, Gilan, Iran. Compression and uplift loading tests were conducted according to relevant standards. On the basis of the field data, a three-dimensional finite element model was developed and subsequently calibrated and verified. The behavior of micropiled rafts subjected to uplift, which is a typical type of loading in foundations of 230 kV four-circuit lattice towers, was then studied by means of this model in terms of a wide-ranging parametric study. In the sensitivity analyses, the impacts of various parameters, such as micropile spacing-to-diameter ( s/ d) and length-to-diameter ( l/ d) ratios along with undrained shear strength of the soil, on the uplift capacity of an individual micropile within and out of the group were investigated. Furthermore, interaction factors were computed based on diverse values for undrained shear strength of the soil, s/ d ratio, l/ d ratio, and grout-soil adhesion. From design and analysis perspectives, the finite element method (FEM) outputs revealed that the efficiency coefficient of micropiled rafts during uplift can be considered equal to one. Moreover, it was found that not only does the behavior of micropiles affect the neighboring micropiles immediately adjacent to the loaded one, but it also influences those in further rows, the result of which would be considering their significance as well. [ABSTRACT FROM AUTHOR]

In this study, a wide‐area fault‐location (FL) method for power transmission lines is proposed. Impractical installation of modern measuring devices (e.g. phasor measurement unit (PMU)) throughout all network buses, due to lack of telecommunication infrastructures or funds, has imposed problems and a growing concern toward the wide‐area FL problem with a limited number of measurement devices. In the most related researches, the optimal PMU placement problem for the FL and state estimation issues is separately studied. Also, the existence of occasional gross errors in the measurement set, due to cyber‐attacks and various telemetry noise or failure, can bring about the wrong results for the FL algorithms. In the presented study, a PMU placement scheme is proposed for achieving both state and FL observability. Furthermore, by utilising this scheme, a new FL algorithm capable of contemplating gross measurement errors has been proposed. Faulted lines have purposely assumed unknown. In addition, by employing the voltages positive‐sequence components, results have shown immunity in regards to fault type and resistance. Comprehensive numerical simulations on the IEEE 14‐bus, 57‐bus and 118‐bus test systems have demonstrated the effectiveness of the proposed method and provided proof to this claim. [ABSTRACT FROM AUTHOR]

In view of the shortcomings of current image detection methods for icing thickness on power transmission lines, an image measuring method for icing thickness based on remote online monitoring was proposed. In this method, a Canny operator is used to get the image edge, in addition, a Hough transform and least squares are combined to solve the problems of traditional Hough transform in the parameter space whereby it is easily disturbed by the image background and noises, and eventually the edges of iced power transmission lines and un-iced power transmission lines are accurately detected in images which have low contrast, complex grayscale, and many noises. Furthermore, based on the imaging principle of the camera, a new geometric calculation model for icing thickness is established by using the radius of power transmission line as a reference, and automatic calculation of icing thickness is achieved. The results show that proposed image recognition method is rarely disturbed by noises and background, the image recognition results show good agreement with the real edges of iced power transmission lines and un-iced power transmission lines, and is simple and easy to program, which suggests that the method can be used for image recognition and calculation of icing thickness. [ABSTRACT FROM AUTHOR]