直流系统作为电厂的重要设备,为信号设备、保护、自动装置、事故照明、应急电源及断路器分、合闸操作提供直流电源。它不受发电机、厂用电及系统运行方式的影响,并在外部交流电中断的情况下,保证由后备电源—蓄电池继续提供直流电源。涉及直流系统改造,要考虑到重要负荷设备不停电转移,风险高,施工难度大,并存在掉电风险,因此,直流系统改造务必要安全、高效、谨慎。二滩水电站一副直流系统已运行十几年之久,设备故障率高,经过前期研究探讨,在确保安全的前提下,高效的完成了本次直流系统改造工作。本文就改造过程做简单的描述,旨在为同行提供借鉴意义。 DC system as an important power plant equipment for the signal equipment, protection, automatic devices, accident lighting, emergency power and circuit breaker points, closing operation to provide DC power. It is not affected by the generator, plant power and system operation, and in the case of an interruption of external AC power, to ensure that the backup power supply - the battery continues to provide DC power. Involving the DC system transformation, taking into account the important load equipment without power transfer, high risk, construction is difficult, and there is the risk of power down, therefore, the DC system transformation must be safe, efficient and cautious. A DC system of Ertan Hydropower Station has been in operation for more than ten years and has a high equipment failure rate. After preliminary studies and discussions, the DC system reconstruction work has been completed efficiently with the premise of ensuring safety. This article on the transformation process to do a simple description, designed to provide reference for peers.