Analysis Of Transmission Lines Research Articles

Transmission line sag and magnetic field analysis with sag parabolic equations and Biot-Savart law

This study presents a novel approach to enhance the precision of calculating sag and magnetic fields beneath overhead transmission lines. The Biot-Savart law is integrated with parabolic equations to assign multiple magnetic field sources to each conductor, resulting in improved prediction accuracy. Addressing oversimplifications in traditional models improves the analysis of transmission lines in real-world scenarios. An analysis was performed using MATLAB and Simulink to validate the effectiveness and broad applicability of different configurations. The results demonstrated a significant improvement in precision compared to traditional methods, indicating that this approach has the potential to establish new benchmarks in the field. This methodology makes significant contributions to electromagnetic studies, offering engineers a reliable tool for designing transmission systems that are both safer and more efficient. This advancement in electrical engineering greatly improves transmission network performance by enhancing sag and magnetic field prediction accuracy. This aids in better maintenance planning and reduces outage risks, resulting in more efficient operations and improved overall performance.

Investigating Low-Frequency Electromagnetic Fluctuations on PCB Surfaces: A Near-Field Analysis of CBCPW Transmission Lines up to 15.2 MHz

Investigating Low-Frequency Electromagnetic Fluctuations on PCB Surfaces: A Near-Field Analysis of CBCPW Transmission Lines up to 15.2 MHz

Vibration suppression analysis of iced transmission lines under axial time-delay velocity feedback strategy

To ensure the safety of power energy transmission channel and mitigate the harm caused by galloping of iced transmission lines, the axial time-delay velocity feedback strategy is adopted to suppress the galloping. The partial differential equation of galloping with axial time-delay velocity feedback strategy is established based on the variational principle for Hamiltonian. Then, the partial differential equation of galloping is transformed into ordinary differential equation based on normalization and the Galerkin method. The primary amplitude-frequency response equation, the first-order steady-state approximate solution, and the harmonic amplitude-frequency response equation are derived by the multiscale method. The impact of different parameters such as time-delay value, control coefficient, and amplitude of external excitation on the galloping response are analyzed. The amplitude under the primary resonance exhibits periodicity as time-delay value varies. The amplitude diminishes with increased control coefficient and increases with external excitation. Comprehensive consideration of various influences of parameters on vibration characteristics is crucial when employing the axial time-delay velocity feedback strategy to suppress galloping. Therefore, to achieve the best vibration suppression effect, it is crucial to adjust the time-delay parameter for modifying the range and amplitude of the resonance zone. The conclusions obtained by this study are expected to advance the refinement of active control techniques for iced transmission lines, and may provide valuable insights for practical engineering applications.

Modeling and Analysis of Multiconductor Transmission Lines by Distributed Transfer Function Method

Multiconductor transmission lines (MCTLs) have various applications in electrical engineering. In modeling and analysis of MCTLs, which are described by a set of coupled partial differential equations, most existing methods rely on approximation or discretization. For high-speed high-frequency applications, accurate analytical methods are always desirable. Such a method, however, is not currently available for complex MCTLs. This paper presents an innovative analytical method for modeling and analysis of MCTLs with various configurations. The proposed method, which is called the Distributed Transfer Function Method, is capable of delivering closed-form analytical solutions for complex MCTLs, in both the frequency domain and the time domain. One highlight of the proposed method is that it gives exact and closed-form solutions for branched transmission lines for the first time. The accuracy, efficiency, and high-frequency utility of the method is demonstrated in numerical examples.

A Novel Metasurface Antenna With Enhanced CP Bandwidth Through Decreasing Q Factor

ABSTRACTThis letter presents a novel metasurface antenna with improved axial ratio bandwidth using parasitic annular sector strips which decreased the Q factor. First, a metasurface antenna composed of a circular patch with etched annular cracks was designed and analyzed through characteristic analysis. Later, to enhance the axial bandwidth, four annular sector parasitic strips were added to decrease the Q factor based on transmission line analysis. In the end, the proposed antenna is fabricated and measured. The results show that the proposed antenna operates in the frequency band from 8.77 to 9.68 GHz; its 3 dB axial ratio bandwidth is 9.19–9.62 GHz, which is significantly improved by 119% compared to the case without the parasitic strips; the maximum gain is 7.2 dBic, which makes it a good candidate for marine search and rescue communications.

Convolutional neural networks-based multi-sensor data fusion analysis for transmission lines

Abstract With the development of the power system, accurate assessment and fault diagnosis of the health status of transmission lines have become increasingly important. However, the standard data fusion algorithms do not fully exploit the correlation and weight disparity among multiple sensors. This study proposes a technique for analyzing transmission lines using a convolutional neural network-based approach to address this issue. By fusing data collected from multiple sensors in different directions, it can more accurately capture key information about transmission lines and conduct comprehensive analysis to evaluate their health status.

Solution and numerical simulation of thermal-structural characteristics model of wire deflagration based on partition coupling time domain propulsion method

The dynamic analysis of transmission lines under the thermal shock load of mountain fire is a complex nonlinear coupling problem of thermal structure. Taking the transmission line as the research object, based on the temperature rise model of mountain fire deflagration space, considering the temperature characteristics of the wire, the mathematical model of the thermal structure coupling characteristics of the wire deflagration is established. In this paper, the partition coupling time domain propulsion method is used to solve the problem. Through MATLAB programming and ANSYS secondary development, the transient characteristics and dynamic response of the coupling effect of the heated structure of the LGJ-400/35 wire with a span of 100 m under different positions and numbers of deflagration points are simulated. It is concluded that the temperature rise rate is positively correlated with the displacement rate and negatively correlated with the stress reduction rate. When the temperature rise rate increases by 0.1 °C/s, the displacement rate increases by 0.0004 m/s. The global deflagration is the most unfavorable mountain fire condition, and the temperature rise rate and displacement rate of the wire under this condition are about 1.3 and 1.9 times that of each single deflagration point condition. The wire temperature is symmetrically distributed with the detonation point symmetrically arranged relative to the mid-span.

Comparative Economic Analysis of Transmission Lines Adopted for Energy-Saving Conductors Considering Life Cycle Cost

Transmission lines serve as pivotal equipment within the power system. Conductors, the primary medium for power transmission and distribution, directly influence the construction cost, operational performance, and long-term benefits of transmission line projects. This study first provides a detailed introduction to the life cycle cost of transmission lines. It utilizes linear regression analysis, the grey model, and the autoregressive integrated moving average model to forecast the electricity sales benefit and quantify the carbon reduction benefits of energy-saving conductors through a methodology. Through the life cycle cost model, we found that operating costs, particularly energy loss costs, dominate the total expenses, accounting for 65% to 66.2%. The JLHA3-425 scheme offers the lowest life cycle cost of 22,891.66 k$. Comparing economic indicators like ENPV, EIRR, and DPP confirmed that the JLHA3-425 medium-strength aluminum alloy stranded wire emerged as the most economically viable option among the evaluated schemes, holding substantial promise for fostering economic and environmental sustainability in electrical power transmission.

Green-prepared high-performance electromagnetic wave absorption Ni6W6C/Co2O3@C composites and related broadband absorption device

In recent years, the synthesis of absorbing materials using green and environmentally friendly natural raw materials have become a research topic, but green and environmentally friendly materials with both high performance and simple synthesis steps still need to be developed. In this work, glucose and metal organic framework (MOF) were used to prepare composite materials with strong absorbing ability and low cost. We chose glucose, which is convenient to purchase on the market, as the raw material and constructed MOF derivatives with carbon shell skeleton nanostructures through a simple method of hydrothermal and annealing. Compared to the raw materials of traditional absorbing materials, glucose has environmentally friendly, low-cost and green characteristics. We characterized the microstructure and morphology of the material. In addition, we also analyzed the material composition and absorption mechanism of Ni6W6C/Co2O3@C. We have found from the theoretical analysis and simulation results of transmission lines that the minimum reflection loss (RLmin) value of Ni6W6C/Co2O3@C material at 5.43 GHz and 4.76 mm is −56.68 dB. And the effective absorption bandwidth (EAB) at 2.04 mm can reach 7.12 GHz. We load the best sample to the honeycomb structure, a broadband microwave absorber was designed for simulation. The results show that the broadband microwave absorber can achieve an average electromagnetic wave (EMW) loss of more than 99 % in the 0.3–16.04 GHz frequency band (RL value is less than −20 dB), and an average EMW loss of more than 90 % in the 16.04–18 GHz frequency band (RL value less than −10 dB). The composite structure of glucose and MOF derivatives enhances the dielectric loss of the material and enriches various EMW loss mechanisms. Finally, a green, environmental-friendly, high-performance absorbing material with a simple synthesis method is prepared. These results provide insights into the research on EMW absorption of composite materials and new methods for referring.

Design and Analysis of 400KV Extra High Voltage Power Transmission Lines in Lebanon

This paper aims to design and analyze an overhead AC extra high voltage transmission line in Lebanon, using ACSR conductors, to meet the growing demand for the future. The optimal design will consider various factors to achieve the best system efficiency and performance, while complying with regulations and safety standards, including EHV voltage level, conductor size, number of conductors per phase, cable sag, and other factors, as well as estimating and describing environmental impacts such as conductor surface potential gradient, corona loss, radio interference, and audible and random noise.

Analysis of Electric Power Transmission Lines Through Graph Theory: Protecting Environmental Preservation Areas Through Strategic Planning

Electrical networks consist of generation plants, transmission and distribution substations of electrical en-ergy. Power is transmitted through towers and lines that span hundreds or even thousands of kilometers. To ensure the health, stability of ecosystems and our quality of life, we must protect the environmental areas where transmission lines intersect. Given the global challenges related to sustainability, the conservation of natural resources and the mitigation of climate change, these studies are imperative. Through graph algorithms, especially vertex degree search and depth-first search, we identify alternative routes, avoiding sensitive regions such as conservation areas within the 440kV transmission networks of São Paulo, Brazil. By reallocating energy transport, we can ensure net-work maintenance and reduce environmental impacts from potential accidents. The results highlight the sustainable planning of transmission lines, aligning energy needs with Brazilian environmental conservation efforts, including the Rio State Park Peixe, Aguapeí State Park, Itapetinga State Park and Itaberaba State Park. Combining existing environmental laws with the promotion of sustainable technologies and practices, promoting more efficient use of resources while protecting the environment. Received: 1 November 2023 | Revised: 4 January 2024 | Accepted: 9 May 2024 Conflicts of Interest The authors declare that they have no conflicts of interest to this work. Data Availability Statement The data that support the findings of this study are openly available in Webmap Energy Research Company (EPE) at https://gisepeprd2.epe.gov.br/WebMapEPE/.

Reliability analysis of iced transmission lines under Poisson white noise excitation via path integration method

Reliability analysis of iced transmission lines under Poisson white noise excitation via path integration method

A numerical approach for nonlinear transmission line analysis with bidirectional coupling to lumped-element and particle-in-cell models

In this article, an iterative method for nonlinear transmission lines (TLs) based on the Lax-Wendroff method has been established to describe a bidirectional coupling model of nonlinear lumped-element models, nonlinear transmission line models, and particle-in-cell (PIC) models. The proposed self-consistent global circuit model is achieved through the introduction of the charge conservation equation at the upper plate as the Robin boundary condition and its coupling with the PIC method used for plasma simulation. The effectiveness of the proposed model is validated through five numerical experiments, including nonlinear transmission line coupling to lumped circuits, and the most general case of plasma-TLs-lumped elements model (LEM) coupling systems. This non-linear global circuit coupling model provides a powerful tool for simulating the complex behavior of various physical systems, including but not limited to capacitively coupled plasmas, vacuum electronic devices, and Z-pinches.

The Influence of Ink Chemistry on the Microstructure Evolution and GHz RF Response of Printed Ag Transmission Lines.

High-frequency transmission is limited to the skin depth in metals. Because poor conductivity cannot be compensated for by increasing the conductor thickness as with DC, optimal transport properties are prerequisites for radio frequency (RF) use. Structural and chemical analyses of transmission lines printed using a traditional ink consisting of Ag nanoflakes in a dispersing phase revealed that optimized thermal treatments yielded thorough burnout of the binder, significant grain growth, elimination of the pore volume, and electrical responses that were comparable to values obtained for thermally evaporated, fully dense Ag controls. Specifically, a low DC resistivity of 2.3 μΩ·cm (1.4× bulk Ag) and RF transmission coefficients of 0.87 and 0.75 at 5 GHz and 10 GHz, respectively, were measured in the nanoflake Ag prints. Conversely, in transmission lines printed from a metal-organic decomposition ink, residual chemical contamination impeded diffusion and densification, yielding greater porosity, small grains that are pinned, and a degraded RF response. Reasonably good porosity approximations were obtained from a model based on percolation theory. The results indicate that contaminants at interfaces and pore surfaces impede diffusion, pore elimination, and full densification, and further, alter carrier dynamics and degrade RF response.

Nonlinear Time-domain signal and noise analysis of an active CRLH transmission line for millimeter-wave frequencies

In this paper, time domain signal and noise behavior of an active CRLH transmission line was investigated in the nonlinear regime at millimeter wave frequencies. In this structure, the transistor is considered as three coupled transmission lines and all three drain,gate and source lines are CRLH transmission lines. The left-handed element values for the active CRLH transmission line are calculated in such a way that the phase cancellation effect and dispersion of the CRLH transmission line are reduced. In order to model this active CRLH transmission line, with the assumption of wave propagation in the form of Quasi-TEM, the distributed modeling method is used to extract stochastic telegraphic equation (STE) in the non-linear regime. To model noise sources in the non-linear regime, the Wiener process and modulation functions have been used to model white noise in the nonlinear regime and in the time domain. By applying the finite integration method to stochastic telegraphic equation, the behavior of the signal and noise of the active structure CRLH has been compared with a line of active structure RH and the obtain results of the numerical method have been verified with the results of the Agilent ADS software.

Failure mechanisms and seismic fragility analysis of overhead transmission lines incorporating pile-soil-structure interaction

Overhead transmission lines (OTLs) are responsible for long-distance electric power transmission from power plants to end-users, inevitably passing through seismically active regions. A thorough literature review regarding seismic design and assessment of various structures underscores the significance of incorporating soil-structure interaction (SSI) and depth-varying spatial effect (DVSE). However, previous studies typically assumed that OTLs are fixed directly to the ground, and depth-varying ground motions (DVGMs) are oversimplified as uniform excitations, which may yield questionable structural performance estimations. To address this concern, this paper focuses on investigating the SSI effect on the seismic response and failure mechanism of an OTL subjected to DVGMs. Prior to this investigation, two commonly used methods for modeling the SSI effect in software ABAQUS are compared, with a nonlinear spring-based modeling method deems comparable in accuracy yet superior in efficiency. Subsequently, a refined finite element model of an OTL-soil-pile system is developed utilizing this simplified modeling method, and a group of three-dimensional ground motions varying within layered soils is stochastically synthesized. The influences of SSI and DVSE are systematically explored in terms of the seismic responses, failure mechanisms, and fragility probabilities of the OTL. The results expose the potential of the SSI effect to weaken the seismic capacity of the OTL and increase the risk of failure, while disregarding the DVSE is likely to lead to overestimated outcomes. This research is expected to raise awareness of considering SSI and DVSE in the seismic design and analysis of OTLs.

Integrative Fault Analysis of Transmission Lines using MATLAB and ETAP

This research paper investigates the major issue of power transmission line faults in electrical engineering. Through advanced simulation tools such as MATLAB and ETAP, the study aims to comprehensively analyze various fault circumstances, including symmetrical and unsymmetrical faults, to determine fault Kilovolt Ampere (KVA) or Megavolt Ampere (MVA). Through detailed fault analysis, insights are sought into improving the reliability and efficiency of power transmission networks, consequently minimizing risks of property damage, casualties, and economic disruptions.

Wind-Induced Response Analysis of the Transmission Tower-Line System Considering the Joint Effect

Wind load is one of the main control loads of transmission tower-line systems. Numerical simulation is the main method for studying the structural wind-induced response. The establishment of a refined transmission tower simulation model is the basis for accurately analyzing the dynamic response of a transmission tower-line system under a wind load. This paper first considered the mechanical properties of bolted joints under cyclic loading and established a transmission tower-line system model considering the joint effects. Then, the wind load was generated by the harmonic superposition method, and the wind dynamic time-history analysis of the tower-line system was conducted. The influence of the joint effect on the wind-induced response of the transmission tower-line system was studied, and the effects of turbulence intensity and wind attack angle on the bolted joint slip effect were discussed. The results showed that the joint effect significantly increased the displacement response of the transmission tower subjected to wind loads and affected the normal service performance of the tower-line system. When the turbulence intensity is 10%, the top displacement of the tower model considering the joint effect is approximately 2 times that of the ideal rigid frame model. After considering the joint effect, the additional [Formula: see text] effect caused by the increased displacement resulted in an increase in the stress of 75.6% members, and the maximum stress of the main member was located near the upper diaphragm of the tower leg. Therefore, considering the joint slip effect in angle steel transmission towers can improve the accuracy of the dynamic response analysis of transmission lines.

Design and Analysis of Transmission Lines Connecting Power System Generators to the Grid

According to the actual requirements, it is necessary to design a line connecting the 150MW hydropower station and the 230KV hydropower station. The first is to plan the overall process of the project, by consulting the data, objectively evaluating the transmission line parameters, combining Matlab and Excel to calculate the transmission line parameters, including barrier current calculation and safety analysis, and finally combining power system simulation and cost calculation, the only one is selected from hundreds of scenarios. Rationale, power flow analysis, and power loss analysis are used to evaluate transmission lines, including series reactors and new transmission lines in parallel. The process reflects the continuous refinement of the initial design to create a transmission line that is both economical and safe.

Electric Field Calculation and Comparative Analysis of Conventional and Unconventional Transmission Lines

Electric Field Calculation and Comparative Analysis of Conventional and Unconventional Transmission Lines