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The purpose of this study is to solve the key technical problems of the practical application of electric robots. The UHV multi-split transmission line power cable operation robot is an important equipment to ensure the reliable operation of high voltage lines and is a useful exploration to realize high-quality power transmission. As the robot system platform equipment mature and operation environment gradually become more complex, the double arm coordination motion control in extreme environment becomes one of the main bottleneck for its practical in power system.

This paper summarizes the key technologies related to power cable robots, and aims at key technical indicators such as operation reliability, operation efficiency and operation quality in the robot’s practical process. The dynamic evolution mechanism of the robot’s mechanical configuration, the multi-physics information fusion algorithm in extreme environments, the robot’s autonomous positioning and its error compensation control, the robot’s robust motion control in extreme environments and the dual-arm force-position hybrid coordination control and the dynamic distribution and elimination mechanism of internal forces in the closed chain between robots and operating objects, all the research methods and solutions of the key technologies are proposed, respectively.

Finally, a new control architecture for power cable robots in the background of the Ubiquitous Power Internet of Things is proposed so as to manage the operation and maintenance of electric power systems. The above key technologies are a new exploration of the operation and maintenance management of EHV (Extra High Voltage) multi-split transmission lines which have laid a solid theoretical foundation for the power cable robot.

High voltage transmission line is the main channel of power transmission. It is an important means to improve the integration of operation and maintenance management of power system to use robot instead of manual inspection and maintenance of power line, in the promotion and application of electric robot. The authors pay attention to the practicability, and the breakthrough of key technologies of robot is the premise of the practicability of robot. In this paper, the robot operation and control in multi-task and complex scenes are studied. The research and implementation of the main key technologies, such as the dynamic evolution mechanism of robot configuration, the coupling and fusion law of multi physical fields in the extreme electric power environment, the autonomous positioning control of manipulator, the robust control of robot in the super electromagnetic field environment and the cooperative operation control of multi manipulator, are discussed.

This paper aims to survey the need for full capacity utilisation of transmission lines in power systems network operations. It proposes a review of the N-1 security criterion that does not ensure reliable dispatch of optimum power flow during outage contingency. The survey aims to enlarge the network capacity utilisation to rely on the entire transmission lines network operation.

The paper suggests transmission line switching (TLS) approach as a viable corrective mechanism for power dispatch. The TLS process is incorporated into a constraint programming language extension optimisation solver that selects the switchable line candidates as integer variables in the mixed integer programming problem.

The paper provides a practical awareness of reserve capacity in the lines that provide network security in outage contingency. At optimum power flow dispatch, the TLS is extended to optimal transmission line switching (OTLS) that indicates optimal capacity utilisation (OCU) of the available reserve capacity (ARC) in the network lines.

Computational efficiency influenced the extension of the OTLS to optimal transmission switching of power flow (OTSPF). The application of OTSPF helps reduce the use of flexible AC transmission systems (FACTS) and construction of new transmission lines..

The paper surveys TLS efforts in network capacity utilisation. The suggested ARC fulfils the need for an index with which the dispatchable lines may be identified for the optimal capacity utilisation of transmission lines network.

This paper aims to propose a novel methodology for optimal voltage source converter (VSC) station installation in hybrid alternating current (AC)/direct current (DC) transmission networks.

In this analysis, a unified power flow model has been developed for the optimal power flow (OPF) problem for VSC-based high voltage direct current (VSC-HVDC) transmission network and solved using a particle swarm optimization (PSO) algorithm. The impact of the HVDC converter under abnormal conditions considering N-1 line outage contingency is analyzed against the congestion relief of the overall transmission network. The average loadability index is used as a severity indicator and minimized along with overall transmission line losses by replacing each AC line with an HVDC line independently.

The developed unified OPF (UOPF) model converged successfully with (PSO) algorithm. The OPF problem has satisfied the defined operational constraints of the power system, and comparative results are obtained for objective function with different HVDC test configurations represented in the paper. In addition, the impact of VSC converter location is determined on objective function value.

A novel methodology has been developed for the optimal installation of the converter station for the point-to-point configuration of HVDC transmission. The developed unified OPF model and methodology for selecting the AC bus for converter installation has effectively reduced congestion in transmission lines under single line outage contingency.

The paper proposes to present the effect of the high voltage transmission lines on the metallic pipelines by calculating the induced voltage due to mutual inductance between the two circuits especially in short circuit conditions of high voltage overhead transmission lines.

The electro magnetic transient program (EMTP) is used to simulate the high voltage transmission lines in normal case and in different faulty case conditions. A software is built on MATLAB program (M‐file) to study the effects of various parameters on the magnitude of the induced voltage such as: separation distance between the high voltage transmission line and the metallic pipeline (horizontal distance), different cases of short circuits and normal operation case, the screening factor, and the soil resistivity.

The three‐phase to ground fault gives the least induced voltage, and phase to ground fault case is the most serious case. The induced voltage decreases with increasing the soil resistivity until 400 Ωm and after this, the induced voltage in the metallic pipeline increases with increasing the soil resistivity for all phase fault types.

It does not deal with all types of interference such as capacitive interference.

This technique helps to know the electrical influence exerted by power line on a pipeline. So it can prevent the pipeline from posing a shock hazard rather than corrosion.

This paper presents the effect of the high voltage transmission lines on the metallic pipelines by calculating the induced voltage due to mutual inductance between the two circuits especially in short circuit conditions of high voltage overhead transmission lines.

The purpose of this paper is to present the problem of high‐speed data transmission on flexible printed circuits (FPC) and the common method for transmission signal designs on those FPCs. A new and novel approach using a “voided return path” of the coplanar transmission model is described and the ease of building them in mass production is described.

Microstrip transmission structures with a “mesh” return were studied and illustrated with emphasis on the problems encountered when the signal changes direction. A new solution using the “voided” return layer of the coplanar transmission model was proposed, simulated, built and tested.

The use of this novel coplanar structure to solve the problem of gigabit data transmission, with minimum noise and electromagnetic interference on flexible circuits can be achieved at low cost and with the flexibility to have multiple impedances and application for “Dynamic Flex”.

The “voided” coplanar structure has been used successfully. Further, developments are underway to employ a “modified” broadsided‐coupled differential structure that simulated a “twisted pair”.

The paper describes various high‐speed transmission structures on FPC used in computers and servers, combined with high volume mass‐production techniques. It presents the best cost scenario for optimal PCB design flexibility and applications.

High‐frequency performance of printed boards (PBs) — a term which encompasses printed wiring boards (PWBs) and printed circuit boards (PCBs) — is becoming increasingly important in digital circuits and knowledge of the electrical characteristics associated with conductors acting as transmission lines is essential. This paper is an introduction to the electrical theory associated with transmission lines and develops the fundamental principles into formulae of use to PB users, designers and manufacturers. Established equations for calculating propagation delay and characteristic impedance based on physical parameters of conductor configurations are then summarised. The concept of ‘critical conductor length’ is proposed as a method of ascertaining whether control of characteristic impedance is required for a particular transmission line. The paper uses the surface microstrip configuration as a vehicle for mathematical analysis but the analysis is equally applicable to other transmission line configurations such as embedded microstrip, symmetrical stripline and dual stripline for which the associated physical parameter equations are included.

This research paper aims to investigate the change detection filter technique with a decision tree-based event (fault type) classifier for recognizing and categorizing power system disturbances on the high-voltage DC (HVDC) transmission link.

A change detection filter is used to the average and differential current components, which detects the point of fault initiation and records a change detection point (CDP). The half-cycle differential and average currents on both sides of the CDP are sent through the signal processing unit, which produces the respective target. The extracted target indices are sent through a decision tree-based fault classifier mechanism for fault classification.

In comparison with conventional differential current protection systems, the developed framework is faster in fault detection and classification and provides great accuracy. The new technology allows for prompt identification of the fault category, allowing electrical grids to be restored as quickly as possible to minimize economic losses. This novel technology enhances efficiency in terms of reducing computing complexity.

Setting a threshold value for identification is one of the limitations. To bring the designed system into stability condition before creating faults on it is another limitation. Reducing the computational burden is one of the limitations.

Creating a practical system in laboratory is difficult as it is a HVDC transmission line. Apart from that, installing rectifier and converter section for HVDC transmission line is difficult in a laboratory setting.

The suggested scheme’s importance and accuracy have been rigorously validated for the standard HVDC transmission system, subjected to various types of DC fault, and the results show the proposed algorithm would be a feasible alternative to real-time applications.

The purpose of this paper is to introduce a robot mechanism designed for power transmission line inspection. The focus for this design is on obstacle-crossing ability with a goal to create a robot moving and crossing obstacle on not only the straight line but also the steering line.

A novel four-unit tri-arm serial robot mechanism is proposed. Every novel unit designed for pitching motion is based on parallelogram structure, which is driven by cables and only one motor. There is gripper-wheel compounding mechanism mounted on the arm. The prototype and obstacle environments are established, and the obstacle-crossing experiments are conducted.

The novel unit mechanism and robot prototype have been tested in the lab. The prototype has demonstrated the obstacle-crossing ability when moving and crossing fundamental obstacles on the line. The experimental results show that the robot mechanism meets the obstacle-crossing requirements.

The novel robot technology can be used for defect inspection of power transmission line by power companies.

It stands to lower the intense and risk of inspection works and reduce the costs related to inspection.

Innovative features include its architecture, mobility and driving method.

The purpose of this study is to address the efficiency of power losses representation while still reducing the computational burden of an optimal power flow (OPF) model in transmission expansion planning (TEP) studies.

A modified TEP model is formulated with inclusions of linearized approximation of power losses for a large-scale power system with renewable energy sources. The multi-objectives function determines the effect of transmission line losses on the optimal power generation dispatch in the power system with and without inclusion of renewable energy sources with emphasis on minimizing the investment and operation costs, emission and the power losses.

This study investigates the impact of renewable energy sources on system operating characteristics such as transmission power losses and voltage profile. Sensitivity analysis of the performance for the developed deterministic quadratic programming models was analyzed based on optimal generated power and losses on the system.

In the future, a comparison of the alternating current OPF and direct current (DC) OPF models based on the proposed mathematical formulations can be carried out to determine the efficiency and reduction of computation process of the two models.

This paper proposed an accurate way of computing transmission losses in DC OPF for a TEP context with a view of achieving a minimal computation time.

This paper addresses the following objectives: develop a modified DC OPF with a linearized approximation of power losses in TEP problem with large integration of RES. Investigate the impact of RES on system operating characteristics such as transmission power losses and voltage profile.

This paper aims to present the simulation, fabrication and testing of a novel ultra-wide band (UWB) band-pass filters (BPFs) with better transmission and rejection characteristics on a low-loss Taconic substrate and analyze using the coupled theory of resonators for UWB range covering L, S, C and X bands for radars, global positioning system (GPS) and satellite communication applications.

The filter is designed with a bent coupled transmission line on the top copper layer. Defected ground structures (DGSs) like complementary split ring resonators (CSRRs), V-shaped resonators, rectangular slots and quad circle slots (positioned inwards and outwards) are etched in the ground layer of the filter. The circular orientation of V-shaped resonators adds compactness when linearly placed. By arranging the quad circle slots outwards and inwards at the corner and core of the ground plane, respectively, two filters (Filters I and II) are designed, fabricated and measured. These two filters feature a quasi-elliptic response with transmission zeros (TZs) on either side of the bandpass response, making it highly selective and reflection poles (RPs), resulting in a low-loss filter response. The transmission line model and coupled line theory are implemented to analyze the proposed filters.

Two filters by placing the quad circle slots outwards (Filter I) and inwards (Filter II) were designed, fabricated and tested. The fabricated model (Filter I) provides transmission with a maximum insertion loss of 2.65 dB from 1.5 GHz to 9.2 GHz. Four TZs and five RPs are observed in the frequency response. The lower and upper stopband band width (BW) of the measured Filter I are 1.2 GHz and 5.5 GHz of upper stopband BW with rejection level greater than 10 dB, respectively. Filter II (inward quad circle slots) operates from 1.4 GHz to 9.05 GHz with 1.65 dB maximum insertion loss inside the passband with four TZs and four RPs, which, in turn, enhances the filter characteristics in terms of selectivity, flatness and stopband. Moreover, 1 GHz BW of lower and upper stopbands are observed. Thus, the fabricated filters (Filters I and II) are therefore evaluated, and the outcomes show good agreement with the electromagnetic simulation response.

The limitation of this work is the back radiation caused by DGS, which can be eradicated by placing the filter in the cavity and retaining its performance.

The proposed UWB BPFs with novel resonators find their role in the UWB range covering L, S, C and X bands for radars, GPS and satellite communication applications.

To the best of the authors’ knowledge, for the first time, the authors develop a compact UWB BPFs (Filters I and II) with BW greater than 7.5 GHz by combining reformed coupled lines and DGS resonators (CSRRs, V-shaped resonators [modified hairpin resonators], rectangular slots and quad circle slots [inwards and outwards]) for radars, GPS and satellite communication applications.