Transient Stability Enhancement in AC-DC Networks Using Virtual Synchronous Machines

The integration of renewable energy sources into power systems has led to a reduction in traditional synchronous generators, thereby decreasing the overall system inertia and affecting the transient stability of power systems. To address this issue, the concept of Virtual Synchronous Machines (VSM) has been proposed to emulate the behavior of synchronous generators and enhance the stability of power systems. This paper focuses on the stability analysis and improvement of an AC-DC power system using the VSM strategy. Through simulations in MATLAB/Simulink, the performance of the VSM control strategy is compared with the traditional vector control strategy under fault conditions. The results show that the VSM strategy significantly improves the transient stability of the system by reducing rotor angle and speed deviations. Additionally, the combined operation of the VSM and Power System Stabilizer (PSS) further enhances the system's stability.