Physics-Informed Multi-Agent Transient Voltage Support with Simplified UHVDC Receiving-End Characteristics

This paper presents the PIML-agent, a physics-informed multi-agent strategy for transient voltage support in ultra-high-voltage direct-current (UHVDC) receiving-end systems. A stress-risk signal derived from a reduced-order receiving-end model is fused with local, neighborhood, and receiving-area voltage channels in a distributed control law whose coordination gains are learned by derivative-free policy search over randomized physics-model rollouts. On the IEEE 39-bus benchmark, with all controllers sharing one receiving-end model and identical actuator limits, the PIML-agent reduces the receiving-area voltage deviation integral by 87.67–97.48% relative to no control and 76.95–94.84% relative to local rule-based support across six fault, load, delayed-support, corridor, and UHVDC-recovery scenarios, and its six-scenario mean by 60.05% relative to a cooperative multi-agent controller. It shortens the average sub-0.90 pu violation duration from 3.62 s (local rule) to 0.56 s and restores the voltage above 0.95 pu within 0.80–2.14 s after fault clearing. It outperforms every baseline in all 100 unseen randomized disturbances, and gains transferred without retraining to the 140-bus NPCC system achieve a 94.80% reduction relative to no control. The advantage persists under gain perturbations, communication delay and loss, agent outage, measurement noise, stronger disturbances, reduced capacity, and model mismatch.