1. Development of Operation Monitoring Method to Improve Plant Availability
The Sixth Strategic Energy Plan of the Ministry of Economy, Trade and Industry, approved by the Cabinet in October 2021, set the goal of 20–22% nuclear power generation in the domestic power supply mix by 2030. To achieve this, it is important not only to restart existing plants, but also to shorten periodic inspections and operate long-term cycles to improve their availability.
To meet these needs, Hitachi has been developing the Hitachi Advanced Plant Performance Diagnosis System (HAPPS), which monitors and diagnoses plant performance during operation to enhance reliability and efficiency. Unlike methods based on statistical analysis of data, HAPPS is based on plant design information. It can constantly monitor equipment deterioration and instrument abnormalities during operation and helps improve the reliability and efficiency of nuclear plants by providing various values, such as drift monitoring of various flow meters; detection of steam leakage from normally closed valves; improvement of heat output calculations; extension of the instrument calibration period due to long cycle operations; reduction of calibration volume; and optimization of auxiliary power for large-capacity loads.
To help plants operate with high efficiency after being restarted, Hitachi is promoting collaborative creation with customers.
(Hitachi-GE Nuclear Energy, Ltd.)