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Among power generation, transmission and use, distribution is an extremely important link. The distribution system includes a transformer and a variety of high and low voltage electrical equipment, the circuit breaker is a large amount of electrical appliances. The circuit breaker can be used to distribute electric energy, the asynchronous motor is not frequently started and the power line and motor...
With the rapid increase of the substation grade, the number of ultra-high voltage (UHV) transformer is increasing and the noise caused by the vibration of UHV transformer is becoming more and more serious. The vibration of UHV transformer is mainly generated from the magnetostrictive effect of the iron core and the action of the electromagnetic force of the winding. In this paper, the sound intensity...
In this paper, we use a combination of circuit and magnetic field to study simulation analysis of electromagnetic effect on buried metal pipes when lightning 330kV transmission lines. Through the establishment of EMPT time domain simulation model, the distribution characteristics of the lightning current and the current of the tower are obtained when the transmission line tower is struck by lightning...
The identification accuracy of dynamic loadings for the rock roadheader has significant impact on economic benefits and safety productions in coal mines. Aiming at the problems that there are difficulty regarding dynamic load real-time identification when the rock road-header is performing cutting tasks under changing loads, this paper designs software real-time identification when the rock road-header...
As Chinese economy continues to grow, the demand for energy is growing, and transmission lines and gas pipeline construction are in rapid development. As the selecting principles of the power industry and the oil and gas industry on the transmission path are very similar, the parallel closeness and crossing between lines and pipelines occur occasionally, and the impact of transmission lines on oil...
At present, the optical fiber differential protection is widely used in high voltage power grid. However, due to the limitation of technology and equipment, there are still some reasons for the normal operation of optical fiber protection. In this paper, according to the actual operation of the optical fiber differential protection, the impact of optical fiber differential protection is analysed and...
The Internet of things (IoT) has been widely recognized by governments and industry because of its huge application prospect. And more and more attention has been paid to the development of E-commerce. This paper mainly from the network technology and E-commerce perspective, through the technology of IoT in the application of E-commerce analysis, to explore how networking technology and E-commerce...
Spatial navigation disorder is the earliest and most common manifestation of cognitive impairment. Therefore, the observation of spatial navigation ability can provide a basis for the distinction between normal and mild cognitive impairment patients. At the same time, it can improve the cognitive function and delay the decline of cognitive function in patients with mild cognitive impairment. In the...
Recently, a new multiple-input multiple-output (MIMO) transmission scheme termed as receive spatial modulation (RSM) is proposed, which activates a subset of receive antennas to carry additional information bits through the index domain. In this paper, a novel variant of RSM, which is referred to as enhanced RSM (ERSM), is proposed to further improve the system performance, especially in high-mobility...
In order to solve the problem of override trip in high-voltage power supply system of coal mine, a new scheme for preventing override trip is proposed on basis of optical fiber locking control. Referring to a typical mine power supply system, the short circuit protection principle of high-voltage grid based on optical fiber locking is analyzed. The hardware circuit, as well as the control procedures...
Modern power grid has already become one of the pillar industry of the national economy. The safety and steady operation of power grid is closely related to the development of all walks of life, national economy guarantee the fundamental interests of people. So it is significant to guarantee the safety of grid in production, operation, and the electric power supply. In this paper, connecting with...
The principle of digital satellite TV differential timing is illustrated and the error sources that influence timing accuracy are analyzed, which include ephemeris error and error caused by ranging method and signal transmission. Error correction and estimation are also presented. By comparing with Two Way Satellite Time Frequency Transfer method, the results after error correction and data processing...
In response to the inevitable wear of structures, the development of Structural Health Monitoring (SHM) systems has become an important research field. In recent years, many modern SHM methods have been developed to detect, evaluate, and asses the health of a building. However, most of them require training data that include both “normal” class (i.e. when the building is in its “healthy” status) and...
Power grid scale is expanding, more generators with large capacity are used in the power system, the growth of the load current is rapidly, the realization of the major regional power grid interconnection, all of these factors will lead to the fault current level continues to rise, which may lead to serious security problems, even collapse and collapse of the system. This paper proposes a high-speed...
Based on the superiority of wavelet transform about frequency band division and the detection ability of wavelet entropy in disturbance signal and zero sequence voltage, this paper put forwards an algorithm that identifies fault type effectively and quickly by analyzing the relationship between standard deviation of wavelet singular entropy and wavelet energy entropy before the fault a period and...
This paper presents an algorithm of fault feature gene extraction based on time-frequency domain Statistics for the technical challenge of the fault detection radial-structured power distribution networks. By using this kind of approach, a gene bank can be obtained. Then, the typical fault type, such as short-circuit, open-circuit and single-phase grounding fault, can be detected by using this gene...
Recognition of human climbing fences in trans-former substations is very essential in a power substation. This paper proposed an innovative and practical human climbing fences detection method based on image processing. At first, the Gaussian Mixture Model background modelling algorithm is exploited to detect motion objects under a view of fix surveillant camera in a power substation. After obtaining...
In order to solve problems that the parameters of low-frequency superposition have an effect on measuring accuracy of insulation resistance, through theoretical analysis and the verification of a large of simulating experiments, it deeply studied the relationship between the power parameters and measuring accuracy of the cable insulation or fault selection of low-frequency superposition. Then it did...
Intelligent-based protective relays in the power system is currently growing very rapidly with the use of embedded systems and artificial intelligence algorithms. Overcurrent relays operated based on the standard characteristic curve will move toward digital overcurrent relay (DOCR) using a flexible characteristic curve based on the user settings. DOCR with the standard characteristic curve cannot...
Non-orthogonal multiple access (NOMA) is a promising multiple access technique for future wireless communications as it results in high spectral efficiency. NOMA differs from recently adopted orthogonal multiple access techniques in that it superimposes multiple data flows at the same time and same frequency band but with different power levels, and resorts to the successive interference cancellation...
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