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Numeric simulation and experiment comparison were used to determine the component parameter of GIS which have also provided a dynamic circuit model. The physical process of arc re-ignition is studied based on the theory of arc energy conservation in this paper. Mayr-Schwarz arc equation is applied to establish the model of arc resistance model. A new transient circuit model which simulated disconnector...
Research on the problem of partial discharge after spraying zinc that has important significance for the insulation analysis and improved of solid-insulated ring main units. In this paper research object is 12kV solid-insulated ring main units' insulation cylinder, finite element analysis method is used, in the view of electric field concentration on the end of line insulation sleeve when the surface...
Three degrees of freedom air-bearing Spacecraft simulator have been used for spacecraft attitude determination and control hard verification and software development. In this paper, some details about the simulator are described. The equation of motion of the platform and proof masses on which are deduced according to the assumption that the total angular momentum is zero. An important feature of...
According to the theory of the thin plate and beam bending of elastics mechanics and taking the hypothesis of G.kirchhoff into account, a finite element model of the platform is built. Based on the theory of deformable body mechanics and kinetics, the formulary for the mass-center elastics displacement of the platform caused by deforming was deduced. Depending on the theory of the spacecraft attitude...
A new method to calculate very fast transient over-voltages (VFTOs) in transformer windings has been presented. The applied algorithm uses a hybrid model which is a combination of the multi-conductor transmission line model (MTLM) and the single-transmission line model (STLM). The voltages at the end of each coil are calculated with the STLM model. Then, these values are used in the MTLM to determine...
Main insulation structure for 110 kV electric power transformer is improved based on electric field Analysis. FEM is introduced to calculate the electric filed of primary and improved main insulation structure. The electric field distribution is shown, and maximum electric field intensity and its position are given. The advantage for improved main insulation structure is obtained from the cost comparison...
Finite-difference time-domain (FDTD) method is introduced to calculate the transient over-voltage of transformer windings using multi-conductor transmission lines (MTL) model. The termination of windings is characterized by VFTO, which is caused by disconnector switching off short bus. Discrete formulation of transformer windings in the time domain is given. Several representative curves with respect...
A New type of main insulation structure for 35 kV electric power transformer with the advantages in more compact structure and lower manufacture costs is designed based on electric field analysis. FEM is introduced to calculate the electric filed of new type of main insulation structure. The electric field distribution, maximum and position of electric field intensity are shown. A way of placing angle...
A transient circuit model for the vacuum circuit breaker switching three-phase inductive motor is established and the steep-fronted over-voltages waves caused by chopping current are calculated. Discrete Fourier transform (DFT) is introduced to decompound the step-front transient over-voltage. Several main frequency components are obtained, which are regarded as boundary excitation. The differential...
A time-domain mathematical model of electric field is introduced to calculate the transient electric field of the outdoor vacuum circuit breaker. The lightning impulse voltage is expressed by double-exponential function, which is regarded as a component of the boundary excitation in solved region. Under lightning impulse voltage, the potential distributions curves of external insulation are calculated...
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