Damping Control Strategy of Photovoltaic and Energy Storage System Connected to Complex Power Grid

This paper investigates the damping control strategy of photovoltaic and energy storage system connected to complex power grid. Firstly, the model of photovoltaic parallel synchronous generator connected to the single machine infinite bus system is established, which provides the basis for the stability analysis. It describes an idea of indirectly modulating the dynamic output of synchronous generator by controlling the amplitude of active power or terminal voltage at the outlet of PV and energy storage system, so as to suppress the low-frequency oscillation of power system. Based on this, a general damping injection compensation control structure is proposed, and the parameter design principles of key links such as gain control and phase compensation are given. Finally, the structure, basic principle and parameter design principle of the damping controller are proposed, and its damping effect on low-frequency oscillation mode under multiple operating conditions is verified and analyzed.