With the increasing penetration of renewable energy, the integration of power electronic equipment has fundamentally re-shaped the dynamic characteristics of modern power grids. Due to the lack of support from the main grid, islanded microgrids (MGs) are prone to losing synchronization stability under large signal disturbances. Existing stability studies often focus on single-inverter systems, which have limited performance in multi-inverter scenarios due to the extended computational burden. Therefore, this paper proposes a method for evaluating the large signal stability of MGs composed of grid-forming (GFM) inverters based on the networked oscillator model. Firstly, the equivalent oscillator model of the GFM inverter is established to accurately characterize both the inherent and interactive dynamics of a single GFM inverter, thereby enabling the construction of a networked oscillator model for islanded MGs with a general topological structure. The large signal stability analysis of the system is then carried out analytically, and the frequency stability domain is explicitly derived. Finally, the effectiveness of the proposed method is verified through time-domain simulation and Controller Hardware-in-the-Loop (C-HIL) experiments.

Distributed electric propulsion (DEP) has been proven to be the next-generation propulsion technology for full-electric aircraft and all-electric aircraft. To take advantage of the redundancy of the DEP system, the distributed control method and its related performance have been extensively studied. However, due to the characteristics of the distributed structure, faults of a single agent could propagate through the communication links, making the whole system fail. This paper proposes a fault-tolerant control method to stabilize the DEP system when an inverter single-phase open-circuit fault occurs. The proposed method adopts a distributed structure and could effectively depress the fluctuation of the rotation speed of each thruster without additional requirements for the increase in hardware amount and computational performance. Controller-hardware-in-the-loop (C-HIL) experiments have been conducted, and the corresponding results validate the effectiveness of the proposed control method.

This paper proposes a novel motor synchronization method for unmanned aerial vehicles with distributed electric propulsion system (DEP-UAV). Compared with conventional aircraft with a single motor, propeller management in DEP-UAV is more delicate and represents unique challenges. Specifically, motors with asynchronous rotating speed would generate asymmetric thrusts along the DEP-UAV, which could result in undesired moment imbalance on the aircraft. A model-based distributed control algorithm is developed, which synchronizes the rotating speed of multiple motors to the desired value. The proposed method runs on a sparse communication network, which avoids the system's single-point-of-failure; additionally, the control gains are customized regarding each motor's mechanical characteristics, which ensures the system's dynamic performance without introducing excessive computational cost. The convergence of the proposed method has been analytically proved and its dynamic performance has been validated using a Controller Hardware-in-the-Loop (C-HIL) testbed for DEP-UAV application.