| In recent years,with the development of large-scale power grids and flexible direct current(DC)transmission technologies,DC distribution has attracted considerable attention.Scholars both domestically and internationally have conducted extensive research in areas such as power grid theory,equipment development,and pilot project construction.During the process of DC interruption,the arc,as a non-uniform and unstable physical phenomenon,has a negative impact on the stable operation of power systems.Enhancing the arc extinguishing performance of DC switchgear is a focal point and challenge in the field of DC transmission and distribution.It is of great significance to study the characteristics and correlations of DC arcs under different conditions.This study investigates the influence of sound field on the process of DC arc interruption.By establishing simulation models and conducting experimental verification,the impact mechanisms of sound field on the morphology,characteristics,and interruption distance of DC arcs are explored,and relevant control methods are proposed.This research holds importance in optimizing the interruption process of circuit breakers,improving energy efficiency and safety,as well as reducing energy losses and environmental pollution.Firstly,a two-dimensional simplified model is established using COMSOL Multiphysics simulation software to comprehensively study the influence of sound field on DC arcs.By adjusting parameters such as the voltage of the power supply,the moving speed of the contacts,and the sound pressure intensity and frequency of the sound field,changes in the voltage-current curve,temperature field distribution,and flow field between the contacts are analyzed.The research results demonstrate that the sound field induces periodic oscillations of the air between the contacts,leading to periodic deflection of the DC arc.The oscillation phenomenon is enhanced with an increase in sound pressure intensity and a decrease in frequency.The morphology of the DC arc primarily manifests as the displacement of the central arc column,and under certain conditions,the root of the arc may also experience displacement.The temperature of the arc is primarily influenced by the variation in current magnitude following voltage changes,with insignificant effects observed from the sound field.These research findings reveal the changes in the arc morphology during the process of DC arc interruption caused by the sound field and its impact on the arc’s current-voltage characteristics.Furthermore,a sound wave arc experimental platform is constructed to verify and analyze the effects of the sound field on the morphology and interruption distance of DC arcs.The experimental results indicate that the sound pressure intensity,frequency,and contact moving speed of the sound field all have certain effects on the interruption distance of the arc,with the frequency exhibiting the most significant influence,followed by the sound pressure intensity and contact moving speed.Moreover,by increasing the number of experiments and calculating the average values,the experimental results meet the requirements of normality testing,ensuring the reliability of the experimental outcomes.In summary,this study systematically reveals the influence of sound field on the process of DC arc interruption through simulation and experimental research,and proposes corresponding control methods.Future research can further explore the mechanisms by which sound field affects the morphology and characteristics of arcs,as well as its potential applications in power systems. |
