A high-speed data acquisition system based on FPGA for tokamak.

Area of Science:

• Fusion energy research
• Plasma physics
• Advanced computing hardware

Background:

• The Experimental Advanced Superconducting Tokamak (EAST) requires robust data acquisition for steady-state, long-pulse discharges exceeding 1000 seconds.
• Existing systems may face limitations in speed, precision, or integration for demanding fusion experiments.

Purpose of the Study:

• To design and validate a high-speed, embedded data acquisition system for the EAST device.
• To enhance the capability for continuous, high-fidelity data collection during long-duration plasma operations.

Main Methods:

• Utilized a field-programmable gate array (FPGA) as the master control chip, specifically a Cyclone FPGA.
• Integrated Texas Instruments (TI) analog-to-digital conversion (ADC) chips for signal digitization.
• Developed a modular system architecture with acquisition boards, each housing four ADC chips and supporting eight synchronous channels.
• Implemented data compression and storage via a Peripheral Component Interconnect (PCI) Express interface to a disk array and data server.

Main Results:

• Achieved a maximum sampling rate of 80 MSps (Mega Samples per second).
• Demonstrated a sampling precision of 12 bits.
• Successfully performed continuous sampling for 1250 seconds, validating long-pulse data acquisition capabilities.
• The system integrates signal conditioning, data acquisition, and data processing on a single, highly portable board.

Conclusions:

• The developed FPGA-based data acquisition system meets the high-speed and precision requirements for EAST's long-pulse operations.
• The system's high integration and portability offer a flexible and efficient solution for fusion research data management.
• This advancement supports the goal of achieving sustained, steady-state plasma discharges in fusion devices.