Grid-connected inverter system stability on-line monitoring method and system

The invention discloses a grid-connected inverter system stability on-line monitoring method and system. The method comprises the following steps: acquiring an output current signal of a grid-connected inverter system at a common coupling point; taking the collected output current signal as initial data, and performing data preprocessing on the initial data; inputting the preprocessed data into the trained online stability monitoring model based on the neural network, and outputting a prediction result of the system stability of the grid-connected inverter; wherein output current signals of the grid-connected inverter system under different power grid intensities are taken as sample data, and state labels of the grid-connected inverter system under different power grid intensities are determined based on a Nyquist criterion; and training the stability online monitoring model according to the sample data and the corresponding state labels. According to the invention, a machine learning algorithm is adopted, mo