October 20, 2025 – The full localization replacement of the Reactor Coolant Pump (RCP) Drives for Unit 2 of SPIC's Haiyang Nuclear Power Plant has been successfully completed, adopting a configuration of “4-operation and 1-standby”. The unit was successfully reconnected to the grid on its first attempt.
These RCP Drives were jointly developed by Shandong Nuclear Power Company Ltd. (SDNP), Shanghai Nuclear Engineering Research & Design Institute (SNERDI), and Shanghai Nancal Electric Co., Ltd. This achievement marks the first comprehensive localization of RCP Drives for third-generation AP1000 units. This retrofit significantly enhances the operational reliability and economic performance of the AP1000 units, while strengthening independent controllability.
The following article is sourced from the official WeChat account of Shandong Nuclear Power Company Ltd.
At 08:28 on October 20, Unit 2 of Haiyang Nuclear Power Plant was successfully reconnected to the grid on the first attempt, marking the successful completion of a 20-day outage. The outage was fully managed in terms of safety, quality, and schedule.
The primary task of this outage was the localization replacement of the RCP Drives for Unit 2. The RCP Drive is a key electrical component in third-generation passive pressurized water reactor nuclear power plants like the AP1000. It provides frequency and voltage conversion for the reactor coolant pumps, limits the RCP starting current, and serves as the sole power supply for the RCPs. Each unit is equipped with four RCP Drives, paired with four reactor coolant pumps. To enhance the reliability of the RCP power supply for third-generation passive nuclear power units, SDNP implemented a "Three-Step" strategy over three years to achieve localization of the RCP Drives.
Formulation of the "Three-Step" Strategy
SDNP, in collaboration with domestic research institute and equipment manufacturer, established the "Three-Step" strategy for localizing the RCP Drives.
Completion of Step One
Units 1 and 2 completed the "4-operation and 1-standby" retrofit, adding one standby domestic RCP Drive per unit.
Completion of Step Two
The first localized replacement of an RCP Drive, capable of long-term full-load operation, was completed on Unit 2. Its feasibility and correctness were fully validated through practical application.
Completion of Step Three
During this outage, the final step was achieved – replacing the remaining three RCP Drives on Unit 2. The localization replacement for Unit 1 is planned for its fifth refueling outage.
This retrofit significantly enhances the operational reliability of the RCP Drives and the flexibility of switching to the standby drive. It further improves the operational reliability and economic performance of China's advanced third-generation passive nuclear power units, strengthens independent controllability, and provides a replicable and scalable "SDNP Solution" for similar units in China.
▲ Domestic Reactor Coolant Pump Drive
To ensure the smooth implementation of this outage, SDNP made advance preparations and meticulous arrangements. An headquarters was established to conduct major special project reviews and master schedule rehearsals. Coordinating 17 partner organizations and over 2,100 personnel, a four-level management system of "Coordination - Execution - Supervision - Support" was built, forming a powerful synergy for tackling key tasks. The Command Center operated 24/7, implementing a 30-minute reporting system for primary and secondary tasks. Strict management was enforced for critical path activities, ensuring continuous progress on the main outage tasks.
▲ Members of the Haiyang Nuclear Power Plant Unit 2 Outage Headquarters
In addition to the main task of localizing the RCP Drives, this outage also accomplished 12 major special projects.
▲ Haiyang Nuclear Power Plant Unit 2 Outage Site