Study On The Effect On Navigational AIDS Of High Voltage Overhead Transmission Lines

Electricity development "13th Five-Year Plan" is expected that the whole society electricity consumption will reach 6.8?7,2 trillion kW·h and per capita consumption will reach 5000 kilowatt-hours or so in 2020,which is close to the level of moderately developed countries.The development of the power industry is related to the economic development of the whole country and the progress of the society.Overhead transmission lines have the characteristics of short construction period,low construction cost and easy maintenance,thus becoming the main means of electricity transmission in power industry.Overhead transmission lines are capable of crossing the sea level,river surface and river channel to transmit electricity,so the construction of overhead transmission lines are closely linked to maritime transport industry.High-voltage transmission lines' voltage range is between 110kV and 500kV.The powered lines will generate a corresponding electromagnetic environment and radiate electromagnetic waves,which will disturb electromagnetic wave receiving radar,making officers on watch and pilots prone to misjudgment and affecting the safety of the ship's navigation.The electromagnetic interference generated by electromagnetic environment may also influence the normal usage of the passing ships' VHF,GPS,mobile phones and other equipments.With the construction and development of domestic overhead high-voltage transmission lines,the problem of electromagnetic interference to marine radar and other navigational aids has become more and more obvious,which has aroused the concern of the ship crew and related marine departments.Therefore,it is necessary to study the influence of overhead transmission lines across navigable waterways on the related navigational aids.Most of the relevant research on overhead transmission line interference in China and abroad is to analyze the interference form of overhead transmission lines and to measure the interference.The relevant reference standard "Radio Interference Limits for High Voltage AC Overhead Transmission Lines" has also been formulated by China's electric power sector.The research,aiming at cross-sea and cross-river overhead transmission lines,are generally verified its rationality and feasibility by their design scale and layout scheme.The research on the impact of maritime transport is generally demonstrated whether the clearance level meet the standards of navigation or not,but did not specifically study the overhead transmission lines' influence on the use of maritime radar and other equipments.In order to find out the influence on the ship navigation aids,this thesis has carried out theoretical analysis and measured research,in which the large-span transmission line of Liuheng-Chunxiao 500kV and Luotou waterway 220kV located in Zhoushan,Zhejiang Province was selected.Then the thesis also analyzed the cause of interference phenomenon,measured the degree of interference.At last,some suggestions were put forward to eliminate or decrease the negative influence of electromagnetic radiation on navigation,so as to provide some reference for future navigation.