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A feeder automation (FA) system is usually used by electricity utilities to improve power supply reliability. The FA system was realized by the coordinated control of feeder terminal units (FTUs) in the electrical power distribution network. Existing FA testing technologies can only test basic functions of FTUs, while the coordinated control function among several FTUs during the self-healing process...
The movable contact of conventional air circuit breaker (ACB) includes multiple parallel contacts. The arc motion process directly affects the breaker capacity of ACB. Therefore, it is important to study the arc motion process of multiple parallel contacts model. A three-dimensional (3D) magneto-hydro-dynamic (MHD) model of air arc plasma is built to investigate the arc motion process. The anode of...
Estimation of voltage sags has become increasingly crucial with higher penetration of sensitive devices in the system recently. Single-event indices for voltage sags are essential to form the whole system of estimation. However, it is still difficult to tell how serious a sag is even after the assessment value is got, for there's no reference value to compare with. This paper firstly discussed indices...
Due to its lots of advantages, CT20 type spring operating mechanism is widely used in the 126kV high voltage circuit breaker. This type mechanism should not meet the requirement of higher interrupting capacity circuit breaker while the interrupting capacity is increasing. In this situation, sometimes the vibration of the closing latch during closing may cause the closing process failed if there is...
The erosion of contact material is one of the critical failure mechanisms in switch devices. Thus it is important to study the characteristics of contact erosion. In this paper, a two-dimensional magnetic hydrodynamics (MHD) is established to get physical characteristics of the molten pool in cathode. Gas dynamics and statistical methods are then used for the calculation of the vaporization rates...
Accurate temperature-rise prediction in gas insulated switchgears (GIS) is necessary to reduce the number of heat-run tests during the product development process. An electromagnetic-thermal-fluid coupled model using computational fluid dynamics (CFD) is developed to predict the temperature-rise of a 110-kV three phase GIS in common tank type. The GIS includes the three-position isolation/ground switch...
Porcelain post insulators are widely used in power equipment as insulation-supporting structure. The current standard has clear requirement for the overall strength of porcelain post insulators; however, the operation and maintenance data of various operating conditions show that shed damage is a major failure type of porcelain post insulators. At present, strength verification of cantilever beam...
Transmission line lightning failures threaten safe and reliable operation of power grid. Guangzhou is one of areas with the strongest lightning activities in China. Lightning protection in Guangzhou power grid has reference role to construction and operation of power grid in other places with frequent lighting in China. Therefore, selection of key parameters in leader progression model is studied...
Electrical lifetime is a vital means of assessing the insulation properties of dielectric materials. The hydrolysis process of vegetable insulating oil could generate a lot of acids, which may have a negative impact on the dielectric strength and aging performance of oil-paper insulation. To identify the influence of seven types of acids (formic, acetic, levulinic, oleic, linoleic, palmitic and stearic...
It's easier for the oil-immersed power transformer to fail when moistened. As is known to us all, moisture may cause the great decrease of the breakdown voltage of the oil-paper insulation system. So, the failure probability model of transformer was established in this paper by using the theory of strength-stress model which is successfully used in the mechanical reliability field. The model could...
This paper presents a preliminary study of developing a novel platform for big data management, processing and analysis of modern power systems. The framework comprises a big data acquisition subsystem, a big data analysis subsystem, a decision-making assistance subsystem and an information integration subsystem. For the big data management system, a novel structure is designed according to three...
The subject addressed is to discuss economic efficiency of home-based micro-grids under non-real-time pricing mechanism. Firstly, configurations of investment and return are decomposed in terms of home-based micro-grid under the background of China's current renewable generation policies and residential non-real-time electricity pricing mechanism. Secondly, a mathematic model of cost/benefit is developed...
The intelligent decision-making of Centralized Control Center of Substation (CCCOS) for accident treatment contributes to the self-healing and reliable supply of power system, for which deals with the operation and maintenance of the gird directly. In this background, a novel accident treatment and decision system based on CCCOS is proposed in this paper. At first, the differences in the accident...
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