10Â Hz pellet injection control system integration for EAST

A 10 Hz deuterium/hydrogen pellet injection system (PI20) was deployed for plasma fueling of the Experimental Advanced Superconducting Tokamak (EAST). The pellet injection system requires high vacuum, system state monitoring, remote control, logical sequence of control stages, precise temperature control, safety interlocks, and data publishing. Owing to the requirements of system safety and operational reliability, a Supervisory Control and Data Acquisition (SCADA) system was developed and integrated to provide the functions of pellet injection process control, pellet video capture, vacuum devices control, and data acquisition. In this control system having two-layer architecture, an Omron Programmable Logic Controller (PLC) is used as the lower controller to control the process of pellet fabrication, cutting, acceleration, and relevant vacuum devices. An IPC(Industrial Personal Computer)is used as an upper computer with a LabView runtime environment that enables video capture and data archiving in conjunction with an operator interface (OPI) to monitor and control the status of the lower controller. The control system was successfully applied to the EAST campaign. In this paper, we describe the framework, development details, and experimental results of the control system.