Research on data strorage and reading method of EAST poloidal field power supply

The plasma discharge duration of EAST (Experimental Advanced Super—conducting Tokamak) is designed to be 1000s, the time has exceeded 100s at present. As the core subsystem, poloidal filed power supply(PF) has nearly 200 signals to be stored. For every discharge, the amount of data is very large, the ordinary database can’t meet the requirement of long pulse data storage. This paper uses HDF5 (Hierarchical Data Format) to store the long pulse data, HDF5 is a file format that can store different types of images and data. Using C interface of HDF5 to design a dataset with compound datatype, to realize real-time writing and reading, the primary discharge time is segmented and the data is wrote and read as chunk. Visualization tool Hdfview is used to view the dataset, and Qt is used to read HDF5 file and display waveform. It proves the correctness of compound datatype and chunk dataset, and the feasibility of writing and reading as chunk. Simple time test proves that writing and reading as chunk are efficient.