SRTM X波段数据在电力勘测中的应用

Application of SRTM X Data in Electric Power Survey

电力勘测技术随着测绘仪器和手段方法的进步不断发展,目前主流的模式是基于GNSS(Global Navigation Satellite System,全球卫星导航系统)和航空摄影测量结合的线路航测技术。但是随着地方电网的升级改造,许多低压输电线路采用航空摄影测量成本大,周期长,手续申请繁琐,而新兴的全球DEM数据的发展为室内就进行线路选线,路径优化,断面提取,档距量测,杆塔位的确定,跨越物的统计等提供了新的作业模式。本文应用SRTM X波段数据,基于Global Mapper软件剖面线线性提取功能,进行快速、便捷的输电线路路径断面点的提取。经自开发的数据接口软件,转换成SLCAD(架空送电线路平断面图处理及定位CAD系统)软件可以识别的数据格式,最后生成断面图。并进行初步塔位排定,最后依据档距表实地放样桩位。并通过在青海果洛110 kV工程中的实际应用,探讨了合乎线路规范的精度要求的SRTM数据,并分析了数据质量的可靠性,数据的精度,误差和改进的方法,最后完成线路外业的勘测工作。

The electric power survey technology keeps developing along with the development of surveying instruments and methods. In the wake of developments in GNSS(Global Navigation Satellite System) and line aerial photogrammetry, aerial line photogrammetry mode which is completely different with the conventional line measuring mode has currently become a mainstream. Especially in accompanied by many high precision global DEM data appears, using Google Earth, Global Mapper and a series of GIS software as a platform, the planning and design of transmission line including line route optimization, avoiding the influence of transmission line route, section data extraction, span measurement, tower position, statistics of across substance and so on. Operation mode of transmission line survey can be said to be changing with each passing day, which is a new attempt of traditional photogrammetric model. Especially in the application of Global Mapper platform, it loads many different DEM data to extract transmission line center section and both of left and right edge line section points. Based on three kinds of free and open global digital elevation data which are SRTM DEM, X-band SRTM DEM and ASTER GDEM, profile linear extraction function is applied to extract transmission line section point fast and conveniently. With the development of the data interface software, it is converted into the data format which can be identified by SLCAD software(overhead transmission line flat section map processing and positioning CAD system), and finally generated section map for tower placed pile field lofting. Through the practical application in Qinghai-Guoluo 110 kV project, the SRTM data is investigated to be conformed with the standard line precision requirements, and the reliability of data quality, data accuracy, error and improved methods is analyzed. It is combined with the measured data to correct the elevation data.