【摘要】 特快速暂态过电压（VFTO）仿真研究中，传统电弧黑盒模型因电弧时间常数和散热功率常取经验值会引起VFTO计算结果出现较大误差。对此，该文提出了一种基于双温度磁流体电弧仿真的改进Mayr电弧模型建立方法。首先，建立了双温度磁流体电弧模型，并通过该仿真研究了上述关键参数与电弧电导的关系，建立了改进Mayr电弧模型；其次，搭建了VFTO仿真模型，采用改进Mayr电弧模型和多种传统电弧数学模型计算了特高压GIS隔离开关切合空载短母线过程的VFTO波形；最后，对比分析了各电弧模型的仿真结果与实测结果波形特征的相对误差。结果表明，改进Mayr电弧模型的VFTO仿真结果与实测结果的相对误差较小，计算准确度较高。更多还原

【Abstract】 Gas insulated switchgear(GIS) is the core equipment in ultra-high voltage(UHV) transmission engineering. During the process of closing short busbar in the UHV GIS disconnector, the very fast transient overvoltage(VFTO) will inevitably occur, causing insulation threats to the GIS and connected equipment, polluting the electromagnetic environment of secondary equipment, and seriously affecting the safe and stable operation of the power system. Since the accuracy of VFTO simulation is closely related to the equivalent arc model of the disconnertor, it is of great significance for VFTO simulation to establish an arc model that can more accurately characterize transient arc characteristics. In VFTO simulation studies, the traditional time-varying resistance arc model lacks accuracy and the classic arc black-box models rely too heavily on experimental data. To address the problems, an improved Mayr arc model based on two-temperature magnetohydrodynamics(MHD) simulation is established and applied to VFTO simulation to realize the simulation calculation of VFTO during the process of closing short busbar in the UHV GIS disconnector and verified in accuracy.Firstly, the arc-burning phenomenon during the process of closing short busbar in the UHV GIS disconnector are analyzed, combined with plasma thermodynamic equilibrium conditions and the high frequency characteristics of VFTO. The analysis results show that the arc plasmas in the arc-burning process are in the thermodynamic nonequilibrium state, thus the electromagnetic induction phenomenon cannot be ignored. According to the analysis,the time-varying electromagnetic field control equation is obtained through the Maxwell equation system and Lorentz specification. Subsequently, a two-temperature MHD arc model under multiphysics coupling is established by combining the time-varying electromagnetic field control equation and the airflow field control equation.Through the two-temperature MHD simulation, the arc time constant and heat dissipation power are obtained, the function relationship between the above key parameters and arc conductance is established through parameter fitting, and then the improved Mayr arc model is obtained. Finally, the equivalent model of the electric equipment in the test circuit was selected, and a VFTO simulation model was established, according to the structure of the test circuit, and then the VFTO simulation during the process of closing short busbar in the UHV GIS disconnector is carried out by using the improved Mayr arc model and several traditional arc models as equivalent disconnector module. In addition, the results of VFTO amplitude, main frequency and wavefront rise time of the improved Mayr arc model and several traditional arc models are simulated and compared.The compared results reveal that the VFTO simulation results obtained by the improved Mayr arc model reach great agreement with the measured results, and the VFTO simulation results under the improved Mayr arc model are more accurate than other traditional arc models. Furthermore, the above work shows that the improved Mayr arc model established by two-temperature MHD simulation can more accurately characterize the transient arc characteristics during the process of closing short busbar in the UHV GIS disconnector, improve the VFTO calculation accuracy compared with the traditional arc models, and reducing the dependence of VFTO simulation on experimental data.更多还原