Hybrid Power System Design And Exhaust Gas Purification Of Overhead Catenary Maintenance Operating Vehicle

With the rapid development of railway construction and the continuous increase of subway lines in China,tunnels play an increasingly important role in railway and urban rail transit construction.At present,diesel engines are used as power sources in catenary overhaul vehicles and railroad vehicles for construction and maintenance of Railways and metro lines in China.When working in tunnels,the exhaust gas pollutants produced by diesel engines are difficult to diffuse in time due to the narrow space and poor ventilation conditions in tunnels,especially in the construction of extra-long tunnels,Metro tunnels and large skylights of high-speed railways.The environment inside the tunnel is much worse.The exhaust gas pollutants produced by diesel engine will not only affect the physical and mental health of workers,but also damage the electrical equipment in the tunnel and affect the service life of electrical equipment.It is imminent to develop contact net maintenance vehicle with clean energy.In this paper,combined with the actual situation of construction and maintenance of electrified railway in tunnel and the development direction of new energy sources and diesel engine emissions,hybrid power technology and diesel engine exhaust purification technology are studied.Hybrid power technology of diesel engine and accumulator is used to solve the environmental pollution problems such as air and noise in tunnel operation,to ensure the physical and mental health of workers,and to create a good working atmosphere for the construction of electrified railway in tunnel.Selective Catalytic Reduction(SCR)technology is used to reduce diesel exhaust emissions and make them cleaner.The main contents of this paper are as follows:(1)Investigate the operation requirements of hybrid catenary overhaul vehicles outside and inside tunnels,and put forward the overall technical scheme of hybrid catenary overhaul vehicles.(2)To study the technical scheme of hybrid electric power,which includes two sets of power,diesel engine and storage battery,with interlocking devices between the two sets of power.Diesel engine power transmission system adopts hydraulic transmission box to ensure that the transmission box can receive not only diesel engine power,but also battery power.Battery power transmission system can be established to develop battery management system,inversion system,etc.,to meet the power requirements of overhaul Vehicle operation.(3)To study the emission reduction scheme of diesel engine,the selective catalytic reduction(SCR)technology is adopted in diesel engine to reduce particulate matter(PM)by66.6%and nitrogen oxide(NO_X)by 59%,which meets the national emission standard IV.