Abstract: As the critical standby power supply under the condition of auxiliary power loss in hydropower stations, the emergency diesel generator for dams directly affects the power supply safety of key equipment including dam flood discharge facilities and monitoring systems. Aiming at the existing problems of the diesel generator at Haokou Hydropower Station of Chongqing Yuhao Company, i.e., lacking remote regulation and control via upper computer, and the battery charger failing to realize automatic linkage control according to the operating conditions of the diesel generator, this paper proposes an integrated technical transformation scheme based on the local control unit (LCU) in the dam area. By adding new hardware control loops, establishing PLC linkage logic and upgrading the monitoring configuration of the upper computer, two core functions are realized simultaneously: remote start-stop of the diesel generator via upper computer and automatic switching on/off of the battery charger. Verified by tests under multiple working conditions, the transformed system features complete logic interlocking and accurate response action. It effectively extends the service life of storage batteries and improves the standby reliability of the emergency diesel generator, providing an engineering reference for the intelligent upgrading of emergency power supply systems in similar hydropower stations.