Study Of Mechanism And Application Of Negative Corona Discharge Under Different Knvironmental Conditions

Corona discharge refers to the local self-sustaining discharge of a gaseous medium in an inhomogeneous electric field and is the most common form of gas discharge.Corona on the high-voltage and ultra-high-voltage transmission line conductors in the power system can cause corona power loss,radio interference,television interference,and noise interference.In addition,for high-voltage electrical equipment,corona discharges can gradually destroy the insulation properties of the equipment.However,applications using corona discharge are also extensive,such as dust collectors,bleaching devices,counters,and the like.Due to the complexity of the corona discharge process,the expression of its microscopic physical process has not been fully understood.Therefore,this paper conducts an in-depth study of this complex physical process,especially its specific discharge process analysis under different environmental conditions.First,this paper briefly introduces the physical phenomena that occur during gas discharge.Then,through the summary of previous studies,the traditional needle-plate corona discharge mathematical model is improved,and the charged particle migration diffusion model based on the fluid dynamics equation and Poisson equation is combined with the effect of many different parameters in the discharge.And the photoionization term in the form of Helmholtz equations is coupled in the partial differential equation,thus perfecting the traditional mathematical model.In addition,the influence of environmental parameters on negative corona discharge is taken into account.Secondly,the effects of ambient temperature,relative humidity and atmospheric pressure on negative corona discharge are studied by using the improved negative corona discharge simulation model and multi-physics coupling simulation method.It mainly analyzes the waveform characteristics of negative corona discharge pulses,ie,Trichel pulses,under different environmental conditions.The variation of the peak value of the pulse,the electric field in the space and the distribution of the charged particles,the pulse duration and the pulse frequency with the environmental conditions are specifically studied in the paper.Studies have shown that environmental conditions play a non-negligible role in the negative corona discharge process.The negative corona discharge was verified by the needle plate discharge model,and the accuracy of the improved negative corona discharge model under the condition of changing environmental conditions was verified.Finally,this paper gives a detailed introduction to the practical application of plasma in the form of corona discharge.It mainly includes the application of corona discharge in electrostatic precipitator;the application of low temperature plasma in medical field;the introduction of mechanism of gas discharge and plasma in material modification process.