BriPower Enhances Fusion Research Capabilities with Upgraded High-Power Control System for HL-3 Device

1. ExecutiveAnnouncement and Strategic Context

Theadvancement of plasma control techniques is a critical frontier in magneticconfinement fusion, specifically within the research framework of"Divertor target plate bias-driven SOL helical current control of EdgeLocalized Modes (ELMs)." Effective ELM suppression requires the precisemanipulation of Scrape-Off Layer (SOL) helical currents to generate specificmagnetic field perturbations. To facilitate these complex physics objectives,BriPower has delivered an upgraded bias power supply control system to the HL-3(Tokamak) facility in Chengdu. This upgrade is a strategic necessity for theHL-3 device, enabling the transition from preliminary testing to high-parameterexperimental cycles.

Thedelivery encompasses a high-performance control architecture designed toovercome previous operational thresholds. While prior configurations achieved atotal bias drive current of approximately 500A in quasi-double-nullconfigurations, the new system is engineered to realize the full 1000A designpotential of the power modules. By increasing the operational voltage ceiling,the system provides the drive required to overcome plasma impedance, ensuringthe generation of magnetic field perturbations sufficiently strong to controlELMs.

Thisdeployment marks a transition toward fully integrated, remote-capableoperation, bridging the gap between hardware capability and the sophisticatedcontrol logic required for stable plasma discharges.

2.Technical Specifications: Driving High-Parameter Performance

Toachieve the magnetic field perturbations necessary for ELM control, BriPowerhas enhanced the power supply parameters to ensure high-fidelity currentinjection. Increasing the maximum output voltage from 500V to 700V is theprimary driver for reaching the 1000A design limit under experimental loadconditions. This evolution ensures that the HL-3 device can maintain stablevoltage output even during high-parameter operations.

Thefollowing table summarizes the system’s transition from its baselineconfiguration to the newly delivered specifications:

CoreTechnical Parameters: 500V to 700V Evolution

Froman engineering perspective, BriPower successfully achieved these parameterincreases while maintaining the original physical footprint of the powermodules. This stability in power module volume allowed for seamless integrationinto the existing HL-3 infrastructure. The upgraded system ensures that oncethe current reaches its flat-top stage, voltage ripple remains below 1% of fullscale, providing the stability essential for sensitive physics diagnostics.

Thishardware stability provides the necessary foundation for the system'ssub-millisecond control logic and real-time response capabilities.

3.Advanced Control Logic and Real-Time Responsiveness

In thedynamic environment of a Tokamak discharge, sub-millisecond response times aremandatory for effective real-time feedback loops. The BriPower control systemis architected to process and react to plasma instabilities with extremeprecision, following prescribed waveforms with high fidelity.

Keytechnical differentiators of the BriPower control architecture include:

• Ultra-High-Speed Processing: The system achieves a main     control sampling and calculation speed (DPS) of less than 3μs, allowing     for near-instantaneous adjustment to experimental variables.

• Rapid State Transition: The power supply can transition between different output     states within 5ms, supporting the high-speed feedback required for active     SOL current control.

• Switching Precision and   Safety: The architecture maintains a     power device switching cycle of less than 0.2ms. To ensure reliability     under high-stress conditions, the system incorporates a 2x safety margin     for both current and voltage, with switching overvoltage strictly limited     to twice the operating voltage.

Thesemetrics ensure the power supply remains stable under high-parameter conditions,reducing noise and ensuring the system can reliably drive the diverted targetplates as required by the HL-3 experimental schedule. This controlsophistication is further integrated into the facility's broader safety andcommunication infrastructure.

4.System Integration and Future-Proofing for DT Environments

Asfusion research advances toward Deuterium-Tritium (DT) phases, the requirementfor robust remote operation becomes absolute due to increased radiation andrestricted manual access. The upgraded BriPower system is designed for"DT-readiness," enabling full-parameter operation and maintenance viaremote interfaces within the CODIS (Tokamak Control System) environment.

Thesystem's integration architecture utilizes specialized communication protocolsto ensure data integrity and safety:

• Input/Output Protocols: If implemented via FPGA or microcontroller, the system     utilizes Modbus for all data exchange. In industrial     computer-based implementations, CDA is employed for input     parameters, while EPICS is dedicated to output status and     fault signals.

• Safety Interlocks: Critical safety connections are established via fiber     optics using fail-safe "light-on for normal, light-off for     fault" logic. Design optimizations include signal redundancy to     ensure continuous monitoring.

• UPS   Anti-Power-Interruption: To protect     sensitive experimental hardware, the control system includes an integrated     UPS feature. This provides a >10-minute operational window following a     power loss, facilitating a controlled and safe shutdown sequence.

Theseintegration features ensure that the power supply functions as a reliable,transparent component of the total HL-3 control landscape, validated byrigorous quality standards.

5.Quality Assurance and Operational Excellence

Thedelivery of high-energy physics equipment demands adherence to the moststringent quality and safety protocols. BriPower's processes comply with ISO9001 for quality management and IEC 61010-1 for the safety of electricalequipment. Furthermore, the system was developed within a clean, anti-staticproduction environment with stabilized temperature and humidity to ensure thelong-term reliability of sensitive electronics.

Thevalidation of the HL-3 bias power supply control system followed a tieredacceptance framework:

1. Factory Acceptance Testing (FAT): Rigorous verification of     all technical indicators, performance parameters, and quality     documentation.

2. Delivery Acceptance: On-site confirmation of component quantities, physical     integrity, and documentation upon arrival at the Chengdu facility.

3. Final Acceptance: Joint debugging and performance validation conducted     during actual HL-3 experimental cycles to ensure the system meets FQA3   quality assurance requirements.