Ming Yang

This article proposes a physics-informed multi-scale adaptive graph neural network (PI-MSA) for rapid event detection, localization, and classification (ED-L-C) of single and multi-source coupling events in power systems to prevent large-scale failures. Prior work decomposes ED-L-C tasks into separate classification subtasks. Instead, this work frames ED-L-C as a unified regression problem through a spatial-aware and task-coupled three-dimensional target formulation, enabling one-shot inference of all abnormal events and their class probabilities at both node and edge levels. By incorporating physical grid topology and shortest-path admittance encoding through parallel multi-scale networks, this unified one-stage pipeline enables joint optimization and learning of shared graph features as well as progressive inter-task dependencies. Experimental validation on five power systems of varying scales and configurations demonstrates that PI-MSA achieves over 75% mean average precision and 90% localization accuracy across various scenarios, outperforming traditional methods by over 40% and exceeding state-of-the-art methods by at least 5%. The model maintains robust and accurate event analysis under topology changes and reduced observability conditions while achieving computational efficiency at 225 frames per second, enabling real-time monitoring and analysis for modern power systems.

Dielectric materials are essential in electrical equipment, yet environmental moisture infiltration disrupts internal electric field uniformity, degrading dielectric performance and potentially causing insulation failure. Traditional humidity monitoring methods are unsuitable for live dielectric systems and struggle to achieve the high-resolution spatial localization of microscale moisture. Inspired by the biological response of reef-building corals, we propose a field-activated microsensor (FAM) based on the electroluminescence effect. Integrating FAMs endows dielectric materials with real-time microscale moisture sensing capabilities. Through precisely designed micro-nano structures, FAMs sustainably respond to local electric field distortions induced by moisture. Furthermore, FAMs autonomously construct cross-linked interpenetrating networks to optimize the intrinsic properties of dielectric material. Ultimately, FAMs enable the real-time, in situ, and high-precision detection of microscale moisture under high-humidity and high-field conditions, demonstrating broad application prospects for the condition monitoring and early fault warning of energized dielectric systems.

This two-part paper proposes a device that integrates dc fault isolation with ac/dc fault ride-through capacities. A four-terminal MTDC simulation system and a simplified low-voltage hardware experimental platform are established for demonstrating the functions of clearing the dc fault current and dissipating surplus power. The experimental results are compared with those of a simulation to analyze the feasibility of the proposed device and verify the reliability of the simulation. Using the simulation system, the proposed device competes against representative dc circuit breaker (DCCB) schemes with dc chopper schemes. The proposed device can effectively clear dc fault current and dissipate the surplus power. The proposed device lowers the cost of components by at least 33.7% from those of independently configured DCCBs with dc choppers.

In the flexible multiterminal dc (MTDC) transmission systems, during dc short-circuit faults on the dc overhead line (OHL) and ac short-circuit faults on the ac network of the grid-side converter, dc circuit breakers (DCCBs) and dc choppers are reliable solutions to handle faults, as they ensure uninterrupted operation. However, their high costs challenge their widespread applicability. In this two-part paper, a device with high performance and low cost is proposed. Part I describes the principles of handling ac and dc short-circuit faults, and provides a theoretical analysis of the performance of dc fault isolation (DC FI) and ac/dc fault ride-through (AC/DC FRT). In Part II, the feasibility of the proposed device is validated on a four-terminal MTDC simulation system and a scaled-down hardware experimental platform. The performances and cost-effectiveness of the proposed device with the optimal configuration are compared with those of representative DCCB and dc chopper schemes. The theoretical analysis, simulation/experiment verification, and comparison showcase the potential of the device for enhancing the cost-effectiveness of MTDC systems.

DC circuit breakers (DCCBs) and dc choppers are reliable solutions for flexible multiterminal dc (MTdc) transmission systems under offshore–onshore integration, as they ensure uninterrupted operation during ac/dc short-circuit faults. However, their high costs challenge their widespread applicability. In this article, a multiport hybrid DCCB with integrated energy dissipation capability (MP-IEDC-HDCCB), achieving high performance and lower cost, is proposed. The principle of handling dc faults is given, and the performance is theoretically analyzed, which is verified in a four-terminal MTDC simulation system. Based on the theoretical analysis, the configuration of components is compared with typical schemes. Besides, the feasibility of the proposed device is validated on a scaled-down hardware experimental platform. It can be seen that the proposed device can clear dc fault current within 5 ms and stabilize dc voltage within 10%. Compared to two-port DCCB with dc chopper, this device offers a cost reduction of 58.8% at least. The theoretical analysis, simulation verification, and experimentation showcase the potential for enhancing the cost-effectiveness of MTDC systems.