Lyapunov-based controller enhances MMC-MTDC power system robustness
New LMI design framework ensures fast, safe current regulation under uncertainty.
Multi-terminal DC (MTDC) transmission systems using modular multilevel converters (MMCs) are critical for future sustainable energy grids, but their current controllers face a fundamental trade-off: speed versus robustness. Existing methods either sacrifice transient performance for stability or fail under uncertain operating conditions.
Now, researchers Victor Reyes Dreke, Rahul Rane, and Aleksandra LekiΔ have published a paper (arXiv:2606.10923) proposing a linear matrix inequality (LMI)-based framework that synthesizes a less conservative static state-feedback controller. By leveraging Lyapunov stability conditions, the controller explicitly accounts for system constraints like input saturation and overcurrent limits. Validated on the CIGRE MT-HVDC benchmark via real-time digital simulation (RTDS), the method shows superior performance over existing approaches, enabling safer and faster current regulation across a wide range of uncertainties.
- The controller uses Lyapunov stability conditions to design a static state-feedback law via LMI optimization.
- It explicitly handles input saturation and overcurrent limits, a critical safety constraint for MMC converters.
- Tested on the CIGRE MT-HVDC benchmark in RTDS simulations, outperforming traditional methods in robustness and response speed.
Why It Matters
This design enables more reliable and efficient current control for next-gen HVDC grids, accelerating sustainable energy adoption.