A numerical simulation method for three-dimensional dynamic evolution process of streamer discharge in insulating oil

Abstract

The invention discloses a numerical simulation method for the three-dimensional dynamic evolution process of streamer discharge in insulating oil. The method first establishes a discharge model in insulating oil and an electrohydrodynamic model describing the physical process of discharge in insulating oil, and then determines the control equation Physical quantity parameters, setting physical disturbance points, determining boundary conditions, and meshing the solution domain and boundary, using finite element software to numerically solve and post-process the control equations, and obtain the distribution characteristics of electric field strength and particle concentration in streamer discharge and the spatiotemporal evolution dynamics of discharge channel bifurcation behavior. The invention can directly estimate the electric field strength and the concentration distribution of charged particles when the insulating oil is discharged, quantitatively evaluate the influence of the space charge effect in the process of forming the discharge channel, and can simulate the discharge bifurcation behavior caused by random disturbances, which is a good example of the discharge hazard in the liquid dielectric The research on gender assessment provides important data support and theoretical basis.

Description

【Technical field】 [0001] The invention belongs to the field of liquid dielectric discharge under high electric field, and specifically relates to a numerical simulation method for the three-dimensional dynamic evolution process of streamer discharge in insulating oil. Numerical simulation of dynamic and charge distribution properties. 【Background technique】 [0002] As an excellent engineering liquid dielectric, insulating oil is widely used in large-scale power equipment and pulse power devices, and the electrical insulation and discharge problems under high electric fields are one of the bottlenecks that limit the overall performance and reliability of such equipment. Breakdown in liquid dielectrics is generally considered a form of streamer discharge, meaning all forms of conductive channel formation, such as diffuse and dendritic discharges. The streamer discharge electrode is easy to develop into a flashover or direct breakdown event along the surface, directly destroy...

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Problems solved by technology

However, two-dimensional simulation cannot describe the bifurcation behavior and tree structure of liquid dielectric discharge caused by external physical random disturbances, such as changes in the local density of the dielectric and changes in the local dielectric constant. It is urgent to carry out research on full three-dimensional discharge simulation in insulating oil. This is not only conducive to comprehensively revealing the microscopic dynamic evolution characteristics of liquid dielectric discharge and the bifurcation behavior mechanism of discharge channels, but also provides strong data support for the evaluation of discharge hazards in liquid dielectrics, which has important theoretical value and practical significance

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