Research on Voltage Stability Control System for Electrochemical Energy Storage VSG

In the power system, energy storage technology is an important technology that can provide stable and adjustable power output. Among them, energy storage grid connected inverters (PCS) are widely used to connect electrochemical energy storage systems and power systems, achieving bidirectional energy conversion. In order to better control this system, researchers introduced the concept of Virtual Synchronous Machine (VSG), which simulates the rotation and excitation characteristics of synchronous motors, enabling electrochemical energy storage to be applied in the field of frequency regulation. However, under frequency modulation conditions, electrochemical batteries require frequent charging and discharging operations, which may lead to changes in the power load of the PCS.A second-order linear self disturbance rejection control method including an error robust integral tracking module is proposed to address the problem of reduced output voltage disturbance resistance caused by changes in energy storage power, achieving stable energy storage output voltage. The PSCAD simulation results show that second-order linear self disturbance rejection control can effectively improve the voltage control loop's ability to suppress voltage fluctuations and enhance the robustness of the energy storage VSG control system.