Environment-friendly arc extinguishing gas rapid screening method based on one-dimensional arc model

Abstract

The invention discloses an environment-friendly arc extinguishing gas rapid screening method based on a one-dimensional arc model, and the method comprises the following steps: 1, calculating arc plasma parameters of candidate environment-friendly gas, which specifically comprise thermodynamic parameters, transport coefficients and radiation coefficients; 2, establishing a one-dimensional arc model, and solving the one-dimensional arc model based on the arc plasma parameters in the step 1; 3, on the basis of a solving result in the step 2, dividing the arc extinguishing process into three stages, namely a heat recovery stage, a pre-arc medium recovery stage and a post-arc medium recovery stage, and defining and calculating evaluation parameters corresponding to each stage, namely a heat recovery rate RT, a pre-arc medium recovery rate Rpre and a post-arc medium recovery rate Rpost; and step 4, calculating the harmonic average of the rate parameters of the three stages obtained in the step 3, taking the harmonic average as a comprehensive evaluation index of the gas arc extinguishing performance, and indicating that the larger the index value is, the better the gas arc extinguishingperformance is, thereby completing the rapid screening of the candidate environment-friendly arc extinguishing gas.

Description

technical field [0001] The invention belongs to the technical field of electrical engineering and plasma, and particularly relates to a gas arc extinguishing performance evaluation method. Background technique [0002] Arc is a discharge phenomenon that occurs during the opening of a circuit breaker. A good arc extinguishing gas should have high thermal conductivity to quickly remove energy from the arc and high dielectric strength to avoid arc re-ignition in the presence of transient recovery voltages. The existing gas arc extinguishing performance evaluation methods can be divided into experimental methods and numerical methods. Experimental methods include short-circuit fault switching experiments, inductively coupled thermal plasma technology and power semiconductor switching technology, etc., and numerical methods include methods based on 2D and 3D magnetohydrodynamic models. The experimental method is expensive, while the numerical method requires 2D or 3D MHD simula...

AI Technical Summary

Problems solved by technology

The cost of the experimental method is relatively high, while the numerical method requires 2-dimensional or 3-dimensional magnetohydrodynamic simulation, the calculation is complex and time-consuming

Considering the search or screening of potential arc extinguishing gases in engineering, especially environmentally friendly SF 6 To replace gas, it is necessary to test a large number of candidate gases or mixed gases, and to constantly change the breaking current, gas pressure and other conditions. However, conventional experimental methods and numerical calculation methods cannot meet the requirements of cheap and fast evaluation of gas arc extinguishing performance. In particular, it cannot be effectively applied to find potential environmentally friendly SF 6 alternative gas

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