Small signal stability analysis of PV-BESs based on discrete state space

New energy is gradually replacing fossil energy and becoming the main source of electricity. It is of great significance to analyze the small signal stability of new energy stations, while the traditional eigenvalue analysis method has limitations such as difficulty in selecting independent state variables. In this paper, the discrete state space method is applied to photovoltaic-battery energy storage system (PV-BESs) for the small signal stability analysis. The discrete state space model based on the trapezoidal integration rule is first constructed, accompanied by its eigenvalues. Then, the discrete eigenvalues are transformed into those real eigenvalues of the system. Correspondingly, the small signal stability of the system is analyzed. The eigenvalues and participation factors calculated by the two methods are compared to verify the correctness of the discrete state space model.