Reserch On Breaking Arc Restraining Factors Of Bridge-type Contact Under 270V And Dc

As important component of guarantee safe operation of the aircraft power supply system,270 V aviation circuit breaker of DC can cut off fault current of the circuit and widely used in various types of aircraft.In the interrupting process of the circuit breaker,arc may form in the contact.The arc will make the surface of the electrodes to melt and erosion,even endanger the insulation materials,which seriously harm the safety of the power system.Meanwhile,With the development of the aviation industry,the demand of power level is higher and higher.In order to ensure that the circuit breaker operate reliably timely and effectively,it is necessary to research the character of arc in the breaking process.So this paper studies restraining factors and extinguishing characteristics of arc to seek the ideal parameters to extinguish arc and to improve arc extinguishing capability of the circuit breaker in different conditions of current and air pressure.Firstly,according to the experimental index,the arc experimental system of bridge-type contact under 270 V and DC,which includes arc experiment device of bridge-type contact and data acquisition system,is designed to complete the DC breaking arc experiment of contact initial velocity,magnetic field intensity and contact gap.Secondly,the arc extinguishing characters was studied.Based on collected data,the waveform of arc resistance,arc power,arc voltage and arc current are analyzed as the time change.The relationship between electric arc power and voltage are analyzed.And the characteristics of arc voltage and current are researched.Finally,DC arc breaking experiment in different conditions of the factors,which includes circuit current,contact gap,arc chute,transverse magnetic field intensity,initial velocity are designed.And different parameters on the impact of arc extinguishing characteristics is analyzed.Meanwhile when the parameters are in a certain range,this paper uses the method of orthogonal experiment to study different parameters of current,air pressure,transverse magnetic field intensity,contact breaking initial velocity on the influence level of duration.