A Dynamic Inertia Control Method for a New Energy Station Based on a DC-Driven Synchronous Generator and Photovoltaic Power Station Coordination

The inertia control ability of photovoltaic power stations is weak. This leads to the problem that photovoltaic power stations cannot provide effective physical inertia support in the grid-connected system. In this paper, a photovoltaic power station controlled by a synchronous generator and virtual synchronous power generation is taken as the research object. A station-level dynamic inertia control model with synchronous machine and inverter control parameters coordinated is established. Firstly, the weakening of system inertia after a high-proportion photovoltaic grid connection is analyzed. Inertia compensation analysis based on an MW-level synchronous unit is carried out. According to the principle of virtual synchronous control of inverter, the virtual inertia control method and physical mechanism of a grid-connected inverter in a photovoltaic station are studied. Secondly, the inertia characteristics of the DC side of the grid-connected inverter are analyzed. The cooperative inertia control method of the photovoltaic grid-connected inverter and synchronous machine is established. Then, the influence of inertia on the system frequency is studied. The frequency optimization of the grid-connected parameter optimization of a photovoltaic station based on inertia control is carried out. Finally, aiming at the grid-connected control parameters, the inertia control parameter setting method of the photovoltaic station is carried out. The neural network predictive control model is established. At the same time, the grid-connected control model of the MW-level synchronous machine is embedded. The control system has the inertia characteristics of the synchronous generator and the fast-response dynamic characteristics of the power inverter.