Special Session SS21

Modeling and Stability Control of High-Power Converters in Converter-Dominated Grids

---

Introduction:

High-power converters are becoming central to renewable generation, HVDC transmission, energy storage, and power-electronic interfaces. As converter penetration increases, the interaction between converter controllers, grid impedance, synchronous machines, and neighboring converters spans switching, control, electromagnetic, and electromechanical time scales. In weak or mixed AC/DC grids, these interactions may produce wideband oscillations, harmonic amplification, poorly damped modes, or unstable post-fault recovery. This special session focuses on the grid-interactive behavior of high-power converters rather than converter topology or power density alone. It seeks models that connect equipment dynamics with power-system response and control strategies that improve stability without overlooking practical current limits, operating modes, and network changes. Solid-state transformers, HVDC converters, grid-forming storage converters, renewable collection systems, and traction power interfaces are of particular interest. Submissions are encouraged to state model assumptions and stability criteria explicitly and, where feasible, to substantiate the proposed methods through laboratory experiments, hardware-in-the-loop tests, or field measurements. The session aims to bring together researchers working at converter, equipment, and grid levels to identify transferable analysis tools and actionable design principles for converter-dominated networks.

The topics of interest include, but are not limited to:

1. Impedance, state-space, and electromagnetic-transient models of high-power converters and solid-state transformers
2. Multi-converter interactions, weak-grid operation, and wideband oscillation mechanisms
3. Grid-forming/grid-following control interactions and stability boundaries
4. Coordinated damping, harmonic mitigation, and fault ride-through in hybrid AC/DC networks
5. Applications in renewable collection, HVDC, storage, and power-electronic traction systems
6. Experimental, hardware-in-the-loop, and field-data validation of models and control methods

SS21's Session Chair:

---

Assoc. Prof. Feng An, North China Electric Power University, China

SS21's Session Co-chairs:

---

Prof. Zhiguang Lin, China Electric Power Research Institute Co., Ltd., China

Asst. Prof. Shan Jiang, Shanghai Jiao Tong University, China