Switch cabinet internal short circuit arcing pressure rise calculation method based on arc energy thermal equivalence

Abstract

A switch cabinet internal short circuit arcing pressure rise calculation method based on arc energy thermal equivalence comprises the steps: simplifying a switch cabinet according to switch cabinet structure parameters, and obtaining a switch cabinet multi-physical-field solution simplification model; according to a result of a short-circuit explosion test, obtaining arc parameters, wherein the arc parameters comprise a short-circuit current instantaneous value I and an arc voltage U; calculating arc power P = U * I; calculating short-circuit explosion equivalent heat source power; setting temperature-fluid field calculation parameters, a gas model, boundary conditions and initial conditions; and carrying out coupling solution on the temperature-fluid field to obtain pressure rise distribution. The switch cabinet internal short circuit arcing pressure rise calculation method enables complex arc plasma in the switch cabinet to be equivalent to a heat source with a fixed size, and assumes that energy of an arc area is evenly distributed, and obtains the distribution law of short-circuit explosion pressure rise in the switch cabinet through temperature-fluid field coupling solution.

Description

technical field [0001] The invention belongs to the technical field of short-circuit arc burning explosion pressure effect inside a switchgear, in particular to a method for calculating pressure rise of a short-circuit arc burning inside a switchgear based on the thermal equivalent of arc energy. Background technique [0002] As an important control and protection equipment in the distribution network, the high-voltage switchgear's safe and stable operation is crucial to the safety and reliability of power supply, and the internal short-circuit explosion accidents that occur from time to time seriously threaten the safety of equipment, buildings and staff . At present, the ability of the switchgear to resist the overpressure caused by the internal short-circuit explosion is mainly evaluated by means of type testing, but the test research period is long and the cost is high, and the mechanical strength of the cabinet can only be checked qualitatively, and it is difficult to q...

AI Technical Summary

Problems solved by technology

At present, the ability of the switchgear to resist the overpressure caused by the internal short-circuit explosion is mainly evaluated by means of type testing, but the test research period is long and the cost is high, and the mechanical strength of the cabinet can only be checked qualitatively, and it is difficult to quantitatively reveal the pressure generated by the short-circuit explosion The degree of influence of the effect on the cabinet

With the development of computing science, multi-physics simulation calculation has become an important method to study this problem. However, due to the complex structure of the switchgear, the large internal short-circuit arcing energy, complex physical and chemical processes, and the high degree of relevant parameters such as arc plasma, etc. Nonlinearity brings great difficulties to simulation calculations

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