A nonlinear adaptive grid-forming control strategy of VSG based on CGHOA-WOA algorithm

With the increasing penetration of renewable energy sources in power grids, system inertia and damping are gradually decreasing. The Virtual Synchronous Generator (VSG) grid-forming control technology can provide inertia and damping to enhance grid stability. However, the calculation of key parameters, including inertia and damping, in VSG is complex, and the system exhibits poor dynamic performance under disturbance conditions. This paper proposes a nonlinear adaptive VSG grid-forming control strategy based on the Circle Gaussian Hiking Optimisation Algorithm-Whale Optimisation Algorithm (CGHOA-WOA) to improve the dynamic response performance of the system. First, the CGHOA-WOA algorithm is proposed to optimise four key parameters of the VSG. Based on this, considering the effects of inertia and damping on system dynamic performance, a nonlinear adaptive VSG grid-forming control strategy based on the Sigmoid function is proposed to dynamically adjust inertia and damping coefficients, thereby improving the dynamic performance under disturbances. Comparative simulation results demonstrate that, compared with other algorithms, the CGHOA-WOA algorithm achieves faster convergence speed and higher accuracy in parameter optimisation. Moreover, under power and load disturbances, the proposed control strategy demonstrates superior robustness, smaller overshoot, and shorter settling time compared to other control strategies, exhibiting superior dynamic response and steady-state performance.