随着“双碳”目标下以新能源为主体的新型电力系统构建，电能的生产、输送和分配各个环节受山火、覆冰、台风等自然灾害的挑战更加严峻。为此，提出了一种基于全球首颗业务化晨昏轨道气象卫星风云三号E星（FY-3E）的适用于输电线路走廊山火监测的火点判识算法，消除了大太阳天顶角观测条件和卫星视角差异对红外通道探测数据准确获取带来的不利影响，实现了复杂大气观测条件下的云信息提取和云像元火点提取，减少了火点误告警和漏告警。利用混合像元线性波谱分离方法分析表明，FY-3E中红外通道火点探测灵敏度达到静止气象卫星的4倍。在北方某省级电网应用，验证了所提算法的有效性与FY-3E在火点探测灵敏度、空间范围精度、定位精度的优越性，火点定位精度较静止气象卫星可提升1倍以上，能够有效提前输电线路运维部门发现火情时间，降低山火对电网运行的影响。

With the construction of a new type of power system with new energy as the main body under the "double carbon" target, the challenges of natural disasters such as wildfires, icing and typhoons in the production, transmission and distribution of electric energy are more severe. Therefore, a fire point identification algorithm based on the world's first operational dawn-dusk orbit meteorological satellite Fengyun-3E satellite (FY-3E) was proposed, which was suitable for mountain fire monitoring in transmission line corridors, the adverse effects of large solar zenith angle observation conditions and satellite perspective differences on the accurate acquisition of infrared channel detection data were eliminated. Cloud information extraction and cloud pixel fire point extraction under complex atmospheric observation conditions were realized, which reduced fire point false alarms and missed alarms. The analysis of mixed pixel linear spectrum separation method shows that the fire point detection sensitivity of FY-3E mid-infrared channel is 4 times higher than that of geostationary meteorological satellite. The effectiveness of the proposed algorithm and the superiority of FY-3E in fire detection sensitivity, spatial range accuracy and positioning accuracy were verified. Compared with geostationary meteorological satellites, the fire location accuracy can be increased by more than one time, and it can effectively detect the fire time in advance by the transmission line operation and maintenance department, and guide the relevant departments to take timely measures to reduce the impact of wildfires on power grid operation.