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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...
The electric field is crucial to the research on the characteristics of long air gap discharge, which is of great importance to the development of ultra high voltage (UHV) projects. The measuring of electric field is one of the hot spots and makes great sense while doing the research. In this paper, an electric field measurement system based on the integrated electro-optical technology was proposed...
Shielding failure of lightning is the key problem for safe operation of transmission lines. Using Electro-geometry Method to simulate the process of shielding failure, large currents hit a conducting wire hardly, however actually they did sometimes. So, Leader Progression Method is used to analyze the relationship between amplitude of lightning current and other parameters, such as wires position,...
Shielding failure of lightning is the key problem for safe operation of UHV transmission lines. Taking the feature of 1000KV AC double circuit transmission lines into account, the leader progression method with proper criterion was employed. The lightning shielding failure rate of top phase, middle phase and bottom phase of two different transmission line tower types were compute, in three different...
In order to meet the demands of lightning impulse electric field measurements in power system EMC, the design of an electro-optic integrated sensor is presented in this paper. The disadvantage of the Mach-Zehnder structure of the sensor is analyzed, and a novel structure is proposed to solve the problem. The sensor system is established and the calibration of the sensor is carried out. A maximum linear...
The electro-optical modulator based on Pockels effect implements the transition from electrical signal to optical signal. This makes using optical fiber in EMC measurements come true. This paper describes the principle of modulators based on Pockels effect, designs the modulator with high precision, calculates the electric field in the modulator, discusses the parameters of the modulator, and gives...
In this paper, based on the primary principle of transformers, designs the devices structure and the mathematic circuit model of the low profile planar transformers with LTCC (low temperature co-fired ceramic) NiCuZn. FEA (finite element analysis) for the electromagnetic analysis is used to calculate electromagnetic parameters of planar transformers with different winding structures. At last, low...
In this paper, the coupling factor between the primary and secondary windings of low profile planar transformer (LPPT) is studied with finite element analysis (FEA) method, focusing on the coupling factor, the different planar structure is discussed. The electromagnetism simulation model is created in ANSOFT HFSS, and the coupling factor can reach 0.92976. Results of the simulation say agree with...
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