Research On The Characteristics Of Electromagnetic Noise And Suppression Methods Of Pantograph-catenary Arc In Mining Railway Electric Locomotive

The Mining industry railway is an important part of the railway transportation network connecting the National Railway and the mining industry.Improving the efficiency of railway transportation in the mining sector is a great significance for speeding up the turnover of vehicles.The mining sector railway is mainly distributed in coal mines and connects with the neighboring national railway network.It is planned and financed by the coal mine enterprises according to the needs of the coal mine.The system comprise of special rails and railway lines.In China,the mining sector railway li ne is more than 20 thousand km.Therefore improving the efficiency of the railway transportation network in the mining sector is particularly important to speed up the turnover of vehicles and re alize the rapid transportation of goods.With the rapid development of the electrified railway in the mining sector,the electromagnetic noise which is generated by the pantograph arc is increasing prominently in the electrified railway system of the minin g industry.This interference poses a threat to the reliability of the power supply system;it affects the electric locomotive control signals and the effective transmission of communication signal along the railway.What's more,it harms the health of the residents along the railway.Research on electromagnetic interference problems generated by pantograph-catenary off-line is a forefront issue among the pantograph-catenary system problems.The electromagnetic noise of the pantograph-catenary system of the electrified railway experimental system composed of an unique 1m anechoic chamber,a pantograph arc generator,and a pantograph arc detection system.The experimental system can control the off-line state and generate the off-line arc.Moreover,it collects the parameters automatically related to the pantograph catenary arc.The parameters include arc voltage,arc current,contact temperature,contact pressure,arc video signal,electromagnetic field signal etc.These parameters can also be stored and anal yzed at the same time.This paper carried out an experimental study on the characteristics of the radiated electromagnetic noise.A With the experimental system,64 groups of radiation electromagnetic noise experiments were conducted under different contac t force,contact current and sliding speed conditions.The experimental materials are metal impregnation carbon slide and Cu contact wire respectively.The radiated electromagnetic noise is mainly distributed in the frequency band from 30 MHz to 500 MHz.A with the increase of contact current,the amplitude of radiated electric field noise increases gradually as well as th e interference frequency band.A with the increase of contact pressure,the amplitude initially increased and then decreases,the interference frequency band initially became narrow and then widen.This paper also studies as the characteristics of conduction electromagnetic noise.Some off-line experiments were carried out with a self-developed experimental platform under different experimental conditions.The frequency domain characteristics of contact current in the off-line state were analyzed.By analyzing a significant amount of experimental data,some contact current distortion results were achieved under different conditions.The total harmonic distortion rate was calculated to determine the current total harmonic distortion rate characteristic curve of the different experimental conditions.The conduction electromagnetic noise characteristics were studied in view of harmonic distortion.Finally,a mathematical model is obtained by data fitting;the model provides a reliable theoretical basis for the subsequent conduction electromagnetic noise research on the pantographcatenary system.In the end,a new structure of the segmental pantograph slide plate is proposed,which can effectively reduce the rate of the pantograph-catenary.Moreover,through the use of ADAMS software,the new pantograph slide structure is modeled and simulated,and the simulation is carried out with the following th ree aspects: following performance,contact pressure and following speed.The simula tion results show it that is the segmental type sliding plate structure can significantly reduce and the time of pantograph-catenary off-line state,and reduce the rate of the instantaneous contact pressure.This characteristic proves that the segmental type structure of the carbon slide plate can efficiently reduce the electromagnetic noise caused by the off-line arc.