储能系统的参数自适应改进 VDCM 控制策略

During the independent operation of DC microgrids, the integration of numerous power electronic conversion devices, coupled with the power fluctuations of renewable energy sources and variable loads, results in reduced inertia, lower damping, and compromised stability. These conditions often cause significant bus voltage fluctuations, potentially threatening the stable operation of the DC microgrid. To address these challenges, this paper investigates an enhanced virtual DC motor (VDCM) control strategy based on parameter adaptation to improve the transient stability of the bus voltage. The control principle of the virtual DC motor is introduced, and a small-signal model of the energy storage control system is established. An in-depth analysis is conducted on the influence of virtual inertia, damping coefficient, and voltage regulator proportional and integral parameters on system stability, highlighting the parameter requirements during each stage of bus voltage fluctuations. Based on this analysis, functional relationships between virtual inertia, proportional coefficient, integral coefficient, and bus voltage deviation are derived. By dynamically adjusting VDCM and voltage regulator parameters in response to voltage deviations, the proposed strategy effectively reduces recovery time under disturbances and minimizes voltage fluctuations. The correctness and feasibility of the proposed control strategy are validated through a hardware-in-loop experimental system utilizing a real-time digital simulator and rapid control prototyping.