介绍了无人机电力巡检的应用背景，结合国内外的发展现状，提出一种新的无源定位技术——基于图像的输电线杆塔定位技术。给出了基于图像的定位算法，同时分析了误差来源。具有高精确度定位定向系统(POS)的航摄相机能够绘制大比例尺的地形图，绘制地形图的过程实际上是目标定位的过程。将配备有高精确度POS和高清摄像机的载机光电转塔用于无人机输电线路巡检，完成对目标杆塔的实时定位，定位精确度达到5?m。

The application background of Unmanned Aerial Vehicle(UAV) power inspection is introduced. A new passive positioning technology－image-based transmission pole tower positioning technology is put forward. An image-based positioning algorithm is proposed, while analyzing the source of error. The aerial camera with Position & Orientation System(POS) can draw large scale of the topographic map，and The process of drawing the topographic map is actually the target positioning process. Carrier photoelectric turret equipped with high-precision POS system and high-definition camera, is utilized in the UAV transmission line inspection to complete the target tower real-time positioning, with positioning accuracy of 5 m.