Grounding System Research Articles

Distributed Estimation of a Layered Architecture for Collaborative Air–Ground Target Geolocation in Outdoor Environments

To solve the problem of collaborative air–ground target search and localization in large outdoor environments, we adopt a distributed layered architecture and propose a corresponding distributed estimation algorithm, which can produce accurate estimates of interested target position. The air–ground system consists of a single unmanned aerial vehicle (UAV) and several ground platforms. First, for the distributed layered architecture, this article develops unbalanced simple convex combination algorithm using one-shot measurements from the single UAV and all ground platforms to generate global estimates of the stationary target state. The novelty of the proposed algorithm is that it considers the differences in sensor capabilities between the aerial and ground platforms. Then, performance analysis is described to show that the proposed algorithm is obviously superior to the traditional existing convex combination algorithms. Finally, the efficacy of this algorithm is further demonstrated by the simulation experiments and actual geolocation tests.

Influence of the Distributed Grounding Layout for Intercity Trains on the “Train–Rail” Circumflux

The mobile distributed grounding system plays an irreplaceable role in discharging power for intercity trains, including two types of grounding settings (GSs): the working GS provides the pathway for discharging the traction current; the protective GS provides the reference grounding potential for the vehicle-mounted equipment. As both working and protective GSs share the rail as the common current-releasing pathway, the traction current released by working GSs might return the carriage through the adjacent protective GSs, forming as the train body (TB) current which threatens the vehicle-mounted electrical equipment. Herein, an equivalent circuit of the mobile distributed grounding system is built to analyze the TB current. For evaluating the influence brought by TB current on the vehicle-mounted equipment, a 3D finite element (FEM) geometry is launched, meanwhile the comparison of the multi-physical distributions is undertaken when applying different grounding layouts, with the emphasis of the highlighted region containing critical devices.

Automatic Task Planning and Its On-Orbit Verification of Agile Remote Sensing Satellite

An on-board autonomous task planning system is designed and implemented in this article, aiming at the problem that the current remote sensing satellite needs complex instruction support to perform tasks and depends on the ground system too much. The complex earth observation task description and injection decomposition modules are designed in the system. No more than 128 ordered points describe the curve area task or irregular polygon area task, and the complex task is decomposed into several strips according to the satellite imaging width. Then, the task’s orbit, attitude, mobility, energy, and time constraints are calculated through the modules of on-board orbit prediction, agile attitude calculation, track planning, energy prediction, and visible arc calculation. Finally, the on-board autonomous task planning and execution are completed through task solution space search and metatask command generation modules. The on-orbit flight verification is carried out on the high-resolution multimode (GFDM) satellite. The results show that this paper’s on-board autonomous task planning system can complete complex task injection and autonomous planning and finally execute.

Grounding system impedance influence on the surge arrester frequency-dependent model parameters using PSO-GWO algorithm

PurposeThis paper aims to focus on the inclusion of the frequency behavior of grounding system effect on surge arrester (SA) model parameters’ estimation.Design/methodology/approachThe grounding system impedance and its frequency behavior are the factors that have influence on the SA performance. Up to now, the grounding system impedance effect and the frequency behavior of the soil parameters have not been studied for the estimation of the parameters of the SA frequency-dependent model. In this paper, the grounding system’s influence on the SA dynamic model has been simulated for rod- and counterpoise-shaped electrodes. Particle swarm optimization with a grey wolf optimization algorithm has been implemented as an optimization algorithm to adjust the parameters of the SA dynamic model.FindingsThe results show that the frequency behavior of the grounding impedance and soil electrical parameters can impress the optimum parameters of the SA frequency-dependent model and should be considered for more reliable results. Also, the results evidence that the proposed optimization method provides more accurate results compared to other optimization methods.Originality/valueTo the best of the authors’ knowledge, this work is one of the first attempts to investigate the effect of frequency grounding system on SA frequency-dependent model parameters.

Rancang Bangun Sistem Pengiriman Paket Penerobos Kemacetan Berbasis Teknologi Drone

Abstract
 
 Package delivery systems in Indonesia, especially in big cities, are currently less efficient in terms of delivery speed and are not environmentally friendly, besides that traffic congestion conditions are the most significant thing, therefore in this study a drone was made as a package delivery tool by air as breakthrough of traffic jam that can lift a package or document with a 1000 gram weight that will get to the destination faster than using package delivery using motorized vehicles by land. This research uses a developmental research method to design a drone that is in accordance with certain specifications, then the following stages are carried out: collecting data and information, determining frame design, determining hardware specifications, assembling all hardware, wiring electrical equipment, setting up mission planner software, flight tests without loads, flight tests with certain loads, collecting test data. As for the control communication system, it uses a telemetry that is connected in real time between the ground system equipment and the equipment in the air or air system. From the test results obtained drones that can work well. This is evidenced by looking at the experimental data for flight endurance testing, flight speed testing to flight testing with certain loads of flight testing data with a certain range,
 
 Keywords: Drone technology, Telemetry, traffic jam, Delevery system

Implementation Of Generator Grounding Parameters Through Distribution Transformer Using Labview

Determination of the generator neutral grounding system through a distribution transformer can be done through manual calculations. Many parameters are considered in the calculation to obtain the appropriate result there is the possibility of repeated calculations. This is very difficult and causes a large difference in the calculation results. Therefore, a computer-based computing system is needed to overcome these problems. Several papers have developed the calculation of the required generator neutral grounding quantity which considers the voltage level, short circuit fault current, and protection system against ground faults. This paper makes modeling in designing a neutral ground generator using the LabView Graphical User Interface (GUI) application. The goal is to make it easier, faster, and more accurate. As the implementation of the modeling used data from std C62.92.2TM-2017.

Modeling of lightning surges on a grounding system of a tower cascade

Modeling of lightning surges on a grounding system of a tower cascade

Physiological regulation of salicylic acid on Helianthus tubeuosus upon copper stress and root FTIR analysis

Phytoremediation plays an important role in the treatment of heavy metal pollution in soil. In order to elucidate the mechanism of salicylic acid (SA) on copper absorption, seedlings from Xuzhou (with strong Cu-tolerance) and Weifang Helianthus tuberosus cultivars (with weak Cu-tolerance) were selected for pot culture experiments. 1 mmol/L SA was sprayed upon 300 mg/kg soil copper stress, and the photosynthesis, leaf antioxidant system, several essential mineral nutrients and the changes of root upon copper stress were analyzed to explore the mechanism of copper resistance. The results showed that Pn, Tr, Gs and Ci upon copper stress decreased significantly compared to the control group. Meanwhile, chlorophyll a, chlorophyll b and carotenoid decreased with significant increase in initial fluorescence (F0), maximum photochemical quantum yield of PSⅡ (Fv/Fm), electron transfer rate (ETR) and photochemical quenching coefficient (qP) content all decreased. The ascorbic acid (AsA) content was decreased, the glutathione (GSH) value was increased, the superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) activity in the leaves were decreased, and the peroxidase (POD) activity was significantly increased. SA increased the Cu content in the ground and root system, and weakened the nutrient uptake capacity of K, Ca, Mg, and Zn in the root stem and leaves. Spray of exogenous SA can maintain the opening of leaf stomata, improve the adverse effect of copper on photosynthetic pigment and PSⅡ reaction center. Mediating the SOD and APX activity started the AsA-GSH cycle process, effectively regulated the antioxidant enzyme system in chrysanthemum taro, significantly reduced the copper content of all parts of the plant, and improved the ion exchange capacity in the body. External SA increased the content of the negative electric group on the root by changing the proportion of components in the root, promoted the absorption of mineral nutrient elements and the accumulation of osmoregulatory substances, strengthened the fixation effect of the root on metal copper, and avoided its massive accumulation in the H. tuberosus body, so as to alleviate the inhibitory effect of copper on plant growth. The study revealed the physiological regulation of SA upon copper stress, and provided a theoretical basis for planting H. tuberosus to repair soil copper pollution.

A New Model for Correcting and Improving the Sequence Networks Method of Single-Phase Earth Fault to Accommodate All Resistance Grounding Systems

The method of sequence networks is still well-known and widely utilized for analyzing and computing unsymmetrical faults in power system networks today, particularly in solid grounding systems where it was initially introduced for short circuit analysis. When it comes to single-phase earth fault that is a dominant majority type of fault in power distribution grids, different neutral grounding methods with varied impedances result in distinct fault characteristics, to continue utilizing sequence networks could cause inaccurate calculations by the reason of neutral voltage during earth fault does not remain as close to zero as it’s pinned in solid grounding system. As neutral resistance increases gradually, the impact of line-to-ground capacitance becomes more pronounced and can no longer be ignored. In this case, applying sequence networks could lead to calculated results that are far from the actual situations in grids. This paper discovers and proves an obscurely hidden defect of the sequence network, while proposing a new and novel modeling to derive comprehensive equations of fault calculations for all types of resistant grounding systems, including solid grounding, low resistance grounding, high resistance grounding, and ungrounded systems.

Using interpolation method to estimation step and touch voltage in grounding system

Wydawnictwo SIGMA-NOT wydaje czasopisma fachowe informujące swoich czytelników o najnowszych osiągnięciach naukowych i nowoczesnych rozwiązaniach technicznych w Polsce i na świecie, popularyzuje problemy techniczne oraz poszerza wiedzę i kulturę techniczną.

Kernel Function-Based Inverting Algorithm for Structure Parameters of Horizontal Multilayer Soil

A multilayer soil structure model is fundamental to design grounding systems. A new method is presented to invert the structure parameters of horizontal multilayer soil. The structure parameters of soil are determined by analyzing the kernel function of the integral equation of the apparent resistivity. The essence of the proposed method avoids the difficulties encountered in general optimization methods; namely, the calculation of the apparent resistivity and its derivative.

Mechanisms for magnetic skyrmion catalysis and topological superconductivity

We propose an alternative route to stabilize magnetic skyrmion textures which does not require Dzyaloshinkii-Moriya interactions, magnetic anisotropy, or an external Zeeman field. Instead, it solely relies on the emergence of flux in the system's ground state. We discuss scenarios that lead to a nonzero flux and identify the magnetic skyrmion ground states which become accessible in its presence. Moreover, we explore the chiral superconductors obtained for the surface states of a topological crystalline insulator when two types of magnetic skyrmion crystals coexist with a pairing gap. Our work opens perspectives for engineering topological superconductivity in a minimal fashion and promises to unearth functional topological materials and devices which may be more compatible with electrostatic control than the currently explored skyrmion-Majorana platforms.

Fault Diagnosis of HV Cable Metal Sheath Grounding System Based on LSTM

At present, the metal sheath of high voltage (HV) cables generally adopts the cross-bonded grounding method, which brings many types of faults and challenges the monitoring and diagnosis of the operation status of the cables. In order to effectively diagnose various types of faults in the metal sheath grounding system of HV cables, this paper proposes a fault diagnosis method for the metal sheath grounding system of HV cables based on long and short-term memory (LSTM). Firstly, the grounding system model of HV cable metal sheath is established. Secondly, the sheath currents of four faults are analyzed. Based on the sheath current amplitude ratio and phase difference of the same loop and the same grounding box, 14 feature vectors reflecting the operation state of the metal sheath grounding system are constructed. Then, the operation state of 18 kinds of metal sheath grounding systems is simulated, and the fault database is established. Finally, the LSTM algorithm is used to accurately identify the fault of HV cable grounding system. The results show that the LSTM algorithm can effectively diagnose and identify the faults of the HV cable metal sheath grounding system, and the accuracy rate is 100%.

Probabilistic Evaluation Method of Transformer Neutral Direct Current Distribution in Urban Power Grid Caused by DC Metro Stray Current

With the coupling of the DC metro network and urban power grid, the DC metro stray currents flowing into transformers have caused serious DC bias. There is, therefore, a need to evaluate transformer neutral direct currents caused by the DC metro stray current. To achieve this, an evaluation model considering the coupling of DC metro network and urban power grid is proposed. In the modeling principle, metro lines are coupled with grounding grids of transfer stations. The DC metro system and the urban power grid are coupled with the soil and grounding systems. The train operations on DC metro lines are simulated using the Monte Carlo method. And, considering the conditions of one-way conduction devices (OWCDs) and over-voltage protection devices (OVPDs), transformer neutral direct currents are calculated. Moreover, two probability indexes are proposed to evaluate distributions of transformer neutral direct currents. The applicability of the proposed model is verified by comparing the calculation results with test data of the transformer neutral direct current. Using the evaluation model, transformer neutral direct currents are evaluated. The result indicates that substation supplying power to the DC metro network has a large probability of a high-level neutral direct current.

Proposal of analysis method to reduce back-flashover rate taking account of tower footing resistance

<span lang="EN-US">The number of lightning stroke on the tower of the 150 kV Koto Panjang-Payakumbuh transmission line located the rocky area has been observed. The high value of tower footing resistance indicates the occurrence of the back-flashover in the transmission line at intensity of 74%. The back-flashover occurrence is dominantly triggered by the tower footing resistance value. Also, the rate of back-flashover has an effect on the value of the tower footing resistance by considering the number of electrode installations. A design is proposed for the grounding system of the tower footings in order to reduce the rate of back-flashover. The results presenting in numerical simulation indicates that it works properly after adding 4 electrodes. That is to say, installing 4 electrodes in each tower has successfully decreased the tower footing resistance value, back-flashovers rate 80% and 90-95% of present value respectively. The insulator voltage can be reduced to less than half of the present voltages as much as 30-50%. In more detail, in tower 77, the value of the tower footing resistance drops to 2.84 Ω, the flashover rate drops to 0.57/100 km/year and the insulator voltage drops to 0.99 MV when a disturbance occurs.</span>

Restricted Earth Fault Protection in Low-Impedance Grounded Systems With Inverter-Based Resources

A restricted earth fault (REF) protection element provides sensitive detection of ground faults near the neutral of a transformer or a generator. The sensitivity gains from the REF element are especially more valuable when the equipment is low-impedance grounded when the transformer phase differential element (87T) is ineffective. However, the REF element faces several challenges in low-impedance grounded systems, which are becoming more prevalent in inverter-based resource (IBR) plants. Dependability of the REF element may be compromised if the zero-sequence current at the transformer terminal is capacitive for an internal ground fault. Security of the REF element may be jeopardized for external faults, such as a phase-to-phase-to-ground or an evolving fault with current transformer (CT) saturation. Using field events from low-impedance grounded IBR plants and simulations, this paper discusses the challenges and design improvements to an REF element for low-impedance grounded systems. CT selection criteria and setting guidance for reliable operation of the REF element are provided. Finally, the coverage provided by the REF element is compared with the 87T element to highlight its benefits in low-impedance grounded systems.

A Method for Measuring and Adjusting the Detuning of Resonant Grounding Systems With Transient Information After Arc Extinction

The scheme of configuring the Petersen coil after actively measuring the capacitive current of a network has been largely adopted, but the feedback of the compensation state is not usually used. This paper proposes a new method of adjusting the Petersen coil by using the information obtained after arc extinction. Using the equivalent circuit of a single-phase grounding fault in the resonant grounding system, the electrical character are analyzed. It is found that the transient process after arc extinction is the underdamped resonance between the Petersen coil and the capacitance to ground, and the resonant frequency is different from the power frequency. Therefore, the resonant angular frequency and damping ratio of the process after arc extinction can be used to calculate detuning, and the three-phase undervoltage can be used to preliminarily judge whether the system is undercompensated or overcompensated. A method of adjusting Petersen coil to achieve reasonable detuning is given. The effectiveness and accuracy of the theory and the method are supported by simulation and field fault data. The method does not need to add any special equipment or adjust the running state of the existing equipment, and it has high safety.

On the Concept of Russian Environmental Education in the International Context

The paramount importance of mankind in solving environmental problems, the acuteness of which continues to increase, gives rise to a planetary discourse around the concepts of education for sustainable development. The discussion focuses on the issues of their goals, priorities, organization principles, correlationwith environmental education. The article confirms the conclusion of foreign researchers that today there is not a single serious discussion about the transition to sustainable development, which would not include, on the one hand, the change of goals and methods of education and, on the other hand, would not be connected with the mission of environmental education to form a culture of sustainable development. On the example of comparison of conceptual approaches to environmental education in Western (USA) and Eastern (India) countries the author makes a conclusion about their originality as well as similar understanding of problems of environmental education for sustainable development, its goals, principles of realization, place in education for sustainable development. In the light of solution of raised problems, typical for different countries, main provisions of domestic Conception of environmental education in the system of general education (2022) are considered. Both its adherence to general world tendencies and novelty of solutions suggested by it are proved. Ways of making environmental education for sustainable development “transversal” and interdisciplinary character in the general education system are considered: development of metalanguage, common for all school subjects; introduction of basic model of personal environmental culture as a result of environmental education; realization of general subject ecologization technology; use of scientifically grounded system of criteria and indicators of environmental education, as well as combination of its forward-looking and regenerative orientation. The article notes that the key provisions of the concept have been tested for over 10 years in the course of experimental studies in 18 regions of the country in interdisciplinary research, combining pedagogical, culturological, activity, axiological and semiotic approaches.

접지 전위 간섭의 특성을 반영한 접지저항 측정 방법

Domestic low-voltage electrical equipments have an environment prone to ground potential interference, due to the characteristics of grounding system. This ground potential interference affects electrical equipments and communication facilities, and amplify the error of ground resistance measurement. It is desirable to find and eliminate the root cause of ground potential interference, however it is difficult to remove that in an environment such as in a dense urban area or an area adjacent to the transmission line. In this paper, the pattern of the potential interference voltage and the effect on the conventional ground resistance measurement are analyzed based on the actual field measurement cases of the ground potential interference, and propose a ground resistance measurement method that reflects the characteristics of ground potential interference.

Performance of Neutral Grounding Resistance and Solid Grounding on 60 MVA Power Transformer

This research will look at the protection system on a 60 MVA power transformer and compare two grounding systems, namely grounding with Neutral Grounding Resistance (NGR) and Grounding Solid (GS). The performance of the two systems will be seen, which is the most effective and efficient. Soil resistance is directly related to water content and temperature; thus, it can be assumed that the resistance of a grounding system will change according to climate change. To obtain a stable grounding resistance, the grounding electrode is installed at the optimal depth to achieve a constant level of water content. The study began by collecting data and then comparing grounding using NGR with GS and measuring the resistance values ​​of NGR and GS on a 60 MVA Power Transformer. The results of this comparison will obtain data on the NGR and GS resistance values ​​on the 60 MVA power transformer, then analyze and compare these values ​​which will provide a conclusion which of the two systems has the best value for grounding.