Research on High Performance Data Acquisition Technology of High Temperature Reactor I&C System

High temperature reactor units adopt the multiple reactors with one steam turbine scheme, which is to drive one steam turbine system using multiple nuclear steam supply system (NSSS) modules. Each module can run independently. In the nuclear instrumentation and control (I&C) system, more than 30,000 IO point data need to be collected from these multiple modules and sent to the man-machine monitoring system. The data acquisition method of traditional distributed control system (DCS) generally adopts the high-frequency periodic acquisition method, and there are a large number of redundant and duplicate data in the acquisition results. When a large number of data points are written to the same real-time database, the speed of data acquisition into the database slows down, resulting in limited acquisition performance. This paper adopts a multiple subnets acquisition structure with master-slave redundancy, and the data acquisition servers can be horizontally expanded, which tremendously improves the acquisition capacity. Based on this structure, an efficient data acquisition software with multi-thread parallel processing is designed. The controller data is filtered by combining the displacement acquisition and low-frequency periodic acquisition method. It can transmit the changed data in real time and filter a large amount of duplicate data that is ahead of the writing cycle time, and greatly improves the efficiency of the data acquisition. The test results show that the proposed data acquisition system can support as many as 100,000 IO points data. It ensures the high performance communication while meeting the independence and low failure rate requirements of the data acquisition system. (authors)