EAST极向场电源的数据存储及读取方法

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

EAST(Experimental Advanced Super-conducting Tokamak)装置的等离子体放电持续时间设计值为1000s,目前放电长度已超过100s。极向场电源(PF)是EAST的核心系统,有接近200路信号需要进行数据存储,每一次放电的数据量非常大,普通的数据库不能够满足长脉冲数据存储的要求。本文使用HDF5(Hierarchical Data Format)存储长脉冲数据,HDF5是可以存储不同类型的图像和数码数据的文件格式。本文采用HDF5的C接口,设计复合数据类型的数据集,为了实现实时存储与实时读取,将一次放电时间进行分割,并对数据进行分块存储和读取。通过可视化工具Hdfview查看数据集,以及Qt读取HDF5文件并进行波形显示,证明复合数据类型和分块数据集的正确性,以及分块写入与分块读取的可行性,同时对读写时间进行简单的测试,证明分块写入与分块读取方式具有高效性。

The plasma discharge duration of EAST (Experimental Advanced Super-conducting Tokamak) is designed to be 1000 s,the time has exceeded 100 s at present.As the core subsystem,poloidal field power supply(PF) has nearly 200 signals to be stored.For every discharge,the amount of data is very large,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 written and read as chunks.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 chunks.Simple time test proves that writing and reading as chunks are efficient.