High-voltage Tower Research Articles

A Wireless System for Monitoring Leakage Current in Electrical Substation Equipment

In this paper, the design and the development of a remote system for continuous monitoring of leakage currents and ground currents in high voltage electrical substations are proposed. Based on wireless local area network technology, the system can be used to monitor continuously a variety of plants within the substation and has low power consumption with inbuilt overvoltage protection. It consists of a transmitter module equipped with a data acquisition (DAQ) system connected to leakage current and voltage sensors, and a receiver module connected to a remote controller for data processing and storage. The principle of operation and the characteristics of the various components of the system are described. Validation tests have been used to verify its performance in three different test situations: A) laboratory monitoring of the leakage current and voltage of a distribution surge arrester; B) laboratory measurement of the leakage current of an outdoor insulator; and C) field monitoring of the earth current and potential rise of high-voltage tower. The measured results are in close agreement with those recorded directly through a DAQ card with fiber-optic and coaxial cable connected systems. Data processing is carried out at the receiving end so that the monitored parameter is displayed continuously or at specified time intervals. The operation of the system has been tested and proved resilient under high-frequency interference signals such as those generated by corona and surface discharges.

Wavelet-based Analysis of Impulse Grounding Resistance–Experimental Study of the “A”-type Grounding System

This article presents the results of experimental investigation concerned with the “A”-type grounding system's impulse characteristics, which are utilized for grounding of high-voltage transmission line towers. The investigation results point to the presence of high-frequency components in voltage and current signals that are not caused by tower footing response to the impulse current. Additionally, both surge generator coupling and measuring circuit remain their main source. High-frequency components of signals are extracted from voltage and current signals by means of the discrete wavelet transform. In addition to being external influence results, the extracted components have very low energy content as well as short duration. The discrete wavelet transform analysis application has validated the existence of external influences.

Control System Design of Climbing Robot Based on PLC and SCM

High voltage tower climbing robot is mainly used to climb all kinds of tower structure, control system mainly has two aspects, one is the chip microcomputer detecting control system using PIC16F877A as the controller; the other is the total control system used to coordinate various parts of sub function module using the PLC controller as the core. This module control method can improve the efficiency of the whole control system. In addition, the PID algorithm of SIEMENS S7-200PLC is used in catching control, which makes control system more stable and efficient.

The mobilization of aluminum into the biosphere.

Aluminum is currently the most widely used non-ferrous metal, and its extraction and purification from geological stores exceeds that of any other metal except iron (1, 2). In 2013, global primary aluminum production was ~52 million tons (104 billion pounds) or about 15 pounds for very person on the earth (1–4). The global outlook for aluminum demand from developing countries such as Brazil, China, India, and Indonesia is rapidly increasing, due to new applications for aluminum and aluminum alloys in infrastructural support, transportation including automobiles, aviation and aerospace applications, electrical transmission, and the generation of energy, including catalytic zeolites in the petroleum and petrochemical industries (5). Interestingly, the largest “machine” built by humankind is the domestic and international networks for the transmission of electricity. Although traditionally-used copper has a higher electrical conductivity, aluminum is only slightly less so, being lighter, more ductile, and less expensive; aluminum is now widely used for both high-voltage tower construction and the electrical transmission wires themselves (2–5). It has been estimated that within the next 10 years aluminum production will exceed that of the previous 150 years (1–3). This prolific de novo generation of aluminum combined with its highly efficient recycling means this metal is becoming increasingly present in our biosphere, defined as the sum of all ecosystems and living organisms on the earth. This short “Opinion” paper will overview and comment on the current massive mobilization of aluminum into the earth’s biosphere.

Research on Fiber Bragg Grating Sensor Technology

This paper presents a method for the detection of transmission tower. It is a common phenomenon that high voltage and strong magnetic field exist in the environment of high voltage transmission tower. Compared with electronic sensor system, fiber Bragg grating sensing technology could resist harsh environment effectively. As a kind of passive devices, fiber Bragg grating tilt sensor can monitor the tilted state of high voltage tower easily. With the help of on-line monitoring system, we can effectively raise maintenance strategy for high voltage tower and analyze the variation trend of the tower. The system is convenient to repair and maintain the high voltage tower at the same time.

3-D Finite-Element Analysis of Conductive Coupling Problems in Transmission Line Rights of Way

The 3-D finite-element method is applied to compute conductive couplings in a transmission line right of way. The domain under analysis is composed of several underground structures, such as ground wires of high-voltage towers, a coated pipeline section, and a steel-reinforced masonry enclosure. A nonhomogeneous Dirichlet boundary condition procedure is employed to overcome the modeling difficulties of this particular problem. A preliminary test problem to validate this procedure is also discussed.

Research on Integrated Monitoring System of High-Voltage Tower

The monitoring and stable operation of high-voltage tower is an important direction of strong grid research. Transmission monitoring includes the forecast of early faults and real-time state estimation. There is no domestic report on related research. Some simulation in laboratory had been done and little been reported. The research review was carried out in accordance with existing knowledge and research progress summary, using wireless transmission and self-generating as example, to build high-voltage tower monitoring system including power management systems, sensor systems, data processing systems, signal transmission system and remote monitoring system.

Measuring Strain of the Lattice Towers

The paper deals with strain measuring of bolted steel lattice high voltage tower structure on the test field. This measurement was associated to the test according to international standard IEC 60652, Ed. 2.0. If the tower is simulated as a truss structure and we expect the linear behavior of this object then the test data and calculation may show variations. The displacements of screw joint were detected as a source of this variation or non linear properties of structure. The key to this conclusion was detection of peak in measurement data.

Experimental Investigation of Impulse Characteristics of Transmission Line Tower Footings

Understanding the impulse response of tower grounding systems is a key factor in the determination of the lightning performance of transmission lines and the safety voltages near high voltage towers. This paper reports the results of an experimental study on the impulse characteristics of full-scale transmission line tower footings. The ground potential distribution both at the ground surface and below ground was examined under impulse currents and variable-frequency AC currents. Prospective impulse step and touch voltages were determined by measurement of the ground surface potential distribution near the tower base. The behaviour of the impulse resistance of the tower footings under highmagnitude impulse currents was investigated. The non-linear characteristics of the impulse resistance with peak current are demonstrated for the entire tower base and for single tower footings. The soil ionisation inception is found to be dependent on the rate of rise of applied current. The dynamic impulse resistance was used to describe the dynamics of soil ionisation.

Numerical Simulation Analysis of High-Voltage Transmission Tower

With the rapid development of Chinese economy construction, hv transmission line has become the main channel for long-distance power transmission and also the most basic conveyance systems and infrastructure for industrial and mining enterprises. The major coal mine fields in China have hv transmission lines passing above. Coal mining subsidence has an important influence on the line tower. So it is important to study the High-voltage transmission line tower to ensure its safety. In this paper, the model is a High-voltage transmission tower. The mechanical analyses for the tower under different boundary conditions are made by finite element simulation. The results can be used as reference for the design of high-voltage transmission line tower in mining area.

Structural Dynamic Response Monitoring of Power Transmission Tower

In order to study the dynamic response of power transmission lines under mechanical fault, the structural dynamic response monitoring indexes based on the requirement of field measurement were determined according to the structural characteristics of steel towers. The monitoring program was put forward in terms of the monitoring principle and basis of the sensors. The vibration characteristic, dynamic alignment and stress/strain are chosen to be the monitoring indexes. Considering the synchronization function of GPS system, the three monitoring indexes of the large span high voltage tower can be simultaneously monitored by using vibration sensor, GPS and strain sensor. The monitoring scheme can provide the theoretical base for the establishment of early warning system and the collection of dynamic response of steel tower during line break or tower collapse.

Calculation of the Connected Magnetic and Electric Fields Around an Overhead-Line Tower for an Estimation of Their Influence on Maintenance Personnel

The perception of the invisible electromagnetic fields associated with high-voltage overhead-line towers can be a problem during live maintenance work. Furthermore, maintenance personnel report that certain types of towers are more susceptible to electromagnetic fields than others. An insight into the electromagnetic field shapes and strengths around towers can provide us with relevant knowledge about how to avoid areas with strong fields or how to approach them with suitable protection equipment. In this paper, we present a calculation of the 3-D magnetic and electric fields in terms of the influence of a steel tower. The method connects the magnetic and electric quasi-static field calculation approach via the appropriate electric circuit model and equations. Using this approach the electric field potentials of the tower elements are not equal to zero and the contribution of the induced electric field is taken into account. The potentials mainly depend on the value of the current running through the tower elements from the top to the ground. The electric field values for different climbing routes on the tower are calculated and compared with reference values in order to predict an optimal climbing route on the tower.

Un inusual registro de intención de anidamiento de Phalcoboenus Megalopterus a baja altitud en Tacna, Perú

The use of a high-voltage electrical tower by a pair of Phalcoboenus megalopterus (Meyen, 1834) to construct their nest in the agricultural zone of Proter (17o48'S 70o34'O; 490 msnm) in the Valley of Sama, Tacna, Peru was described. Apparently, the birds abandoned the nest after failing to reproduce successfully. Possibly, this is the first record of the intention to nest at low altitude for this species in Peru.

Structural topology optimization of high-voltage transmission tower with discrete variables

In order to solve the structural optimization problem of long-span transmission tower, topology combination optimization (TCO) method and layer combination optimization (LCO) method based on discrete variables are presented, respectively. An adaptive genetic algorithm (AGA) is proposed as optimization algorithm. Four methods: cross-section size optimization (CSSO) method, shape combination optimization (SCO) method, the TCO method and the LCO method, are utilized to optimize the transmission steel tower, respectively. The topology optimization rules are presented for the TCO method, and the layering optimization rules are presented for the LCO method. A high-voltage steel tower is analyzed as a numerical example to illustrate the performance of the proposed methods. The simulation results demonstrate that the calculated results of both the proposed TCO method and the LCO method are obviously better than those of the CSSO method and the SCO method.

A New Frequency-Dependent Surge Impedance Calculation Method for High-Voltage Towers

A new technique for the calculation of the surge impedance of high-voltage towers is presented. The tower is represented by a four-terminal network for which the surge characteristics are determined by solving the transmission-line equations. The boundary conditions of voltage at the top and base of the tower are determined using a numerical solution of the electromagnetic field on a physical model of the tower. The physical model is a multiconductor geometrical model incorporating the conductors forming the main body, the slanted conductors, and the horizontal cross-arms where necessary. In the process of computing the terminal voltages and currents, soil resistivity effects are also taken into account. Surge impedance values obtained using this method are in good agreement with both published analytical formulae and field experiments.

Outbreak of Lead Poisoning in High Voltage Tower Conservators

A changing character of lead exposure has been observed over many years. However, construction workers involved in the renovation of painted steel structures are still severely exposed to lead and its compounds. In 2004, we observed an outbreak of lead poisoning in high voltage tower conservators working abroad. As many as 27 male workers with suspected lead poisoning were hospitalized in the Department of Occupational Disease, Nofer Institute of Occupational Medicine, Lódź, Poland. They were involved in removing an old lead-containing paint from high voltage towers. On admission to the department, 70% of treated workers showed laboratory signs of anemia in their blood count. After treatment the signs persisted in 25% of patients. Also alkaline dotting in erythrocytes was present in 13 subjects. Sub-acute lead poisoning manifested by abdominal cramps with coexisting anemia and increased lead absorption symptoms was most frequently diagnosed. The high lead exposure of the examined high voltage tower cleaners was due to specific working conditions. In such cases overprotection of the environment may lead to severe health effects in humans.

Novel Design of Transmission Towels from Bent Metallic Sections of Nontraditional Shapes

New designs of high-voltage overhead transmission line towers produced from bent metallic shapes are presented. The existing tower designs are analyzed. The new structures are shown to possess substantial advantages. Performance characteristics are compared.

Safety aspects of GSM systems on high-voltage towers: an experimental analysis

Low-voltage (LV) applications mounted on high-voltage (HV) towers may pose a safety problem in the low voltage network when a flashover occurs over the high-voltage insulators. To study the effects experimentally, a 150 kV system was made available. On a high voltage tower carrying a cellular phone base station, one phase insulator was shorted to the tower. A current of about 200 A was injected into that phase at a large distance. We measured the current distribution and the relevant voltages in the low voltage net. The experimental current data agree with EMTP calculations. Appropriate measures to guarantee safety for persons and electronic equipment are discussed.

Safety Aspects of GSM Systems on High-Voltage Towers: An Experimental Analysis

Low-voltage (LV) applications mounted on high-voltage (HV) towers may pose a safety problem in the low voltage network when a flashover occurs over the high-voltage insulators. To study the effects experimentally, a 150 kV system was made available. On a high voltage tower carrying a cellular phone base station, one phase insulator was shorted to the tower. A current of about 200 A was injected into that phase at a large distance. We measured the current distribution and the relevant voltages in the low voltage net. The experimental current data agree with EMTP calculations. Appropriate measures to guarantee safety for persons and electronic equipment are discussed.

Automatic Truss Design by Optimized Growth

A new algorithm for the automatic design of planar truss structures is described. The designer need only specify the location of the supports, and the location and magnitude of the loads. The algorithm allows the computer to automatically synthesize a practical topology for a structure based on these specifications. The technique mimics the natural process of evolution where complex organisms evolve from successful less-sophisticated organisms. Using the proposed synthesis technique, structures are made to grow from a simple generic shape to complex forms along an optimized pathway. As the structure grows, new members are added in an organized fashion. The technique could provide two main benefits. The cost of designing structures could be reduced, and the computer could produce innovative structural topologies that a designer might not consider. The technique is illustrated by presenting the results of synthesizing a design for a high-voltage cable-support tower and by comparing results with a prominent topology optimization technique.