巴西高压直流输电运行情况及启示

Operation Situation of Brazilian HVDC Transmission Grids and Several Enlightenments

直流工程在巴西输电网中占据重要地位,建设和投运时间跨度大,工程运行、维护和管理考核具有本地特点。由于运维监管政策具有挑战性,巴西高压直流工程运维面临确保系统高可靠性和降低运营成本的双重压力。总体而言,背靠背直流工程整体运行情况良好,近年来的能量可用率一直维持在99%以上。从统计数据看,巴西长距离大容量直流输电工程的运行指标受不同设备运维状况影响大:阀和交流设备停电检修时间是影响工程能量可用率的主要原因;备品备件不足是导致换流变故障抢修时间延长的重要原因;长距离直流架空线路拉线塔比例高、线路维护任务重。中资企业丰富的特高压直流工程技术和管理经验有力地支撑了±800 kV美丽山直流输电工程建设和运维,同时,工程实施需要应对中国和巴西两国管理体制、运营模式、标准体系等差异带来的特高压技术落地、入网和运行等方面的挑战。

HVDC project occupy an important position in Brazilian transmission grid and the construction of the project and putting it into operation have been experienced a long period,and its operation,maintenance,management and assessment possess indigenous characteristics.Due to the challenging of the policy of the operation,maintenance and supervision,the operation and the maintenance of Brazilian HVDC project has to face with the double stresses from ensuing high reliability of the HVDC system and decreasing operating costs.In general,the overall operation situation of the back-to-back HVDC project is satisfied,and in recent years the energy availability have been stayed over 99 percent.According to statistical data,the operating indices of Brazilian long-distance high-capacity Itaipúand Madeira HVDC projects are obviously influenced by the operation and maintenance conditions of different equipments,in which the time of interruption maintenance for valves and AC equipments is the main reason effecting the energy availability,the shortage of spare parts is the important reason leading to prolong the time for urgent repair of the converter transformer failure,besides,there is a higher proportion of selfsupporting towers in the long-distance HVDC overhead transmission line and the tasks of line maintenance are arduous.Although the extensive management experiences of Chinese funded enterprises in the field of HVDC transmission technology and management powerfully support the construction,operation and maintenance of±800 kV Belo Monte HVDC project,however the project implementation still has to face with the challenges in UHVDC technology localization,integration into existing power grid and operation due to the differences in the aspects of management system,operation pattern and standard system between Brazil and China.