Method and system for analyzing grid-connected node frequency of each generator in wind-water combined system

The invention discloses an analysis method and system for grid-connected node frequency of each generator in a wind-water combined system, and the method comprises the steps: classifying nodes in the wind-water combined system containing wind, water and load, and solving a system susceptance matrix according to the classified nodes; according to the water turbine governor control model and the doubly-fed fan frequency control model, simplified transfer functions of the water turbine and the doubly-fed fan in the complex frequency domain are written respectively; and according to the susceptance matrix of the system, the simplified transfer functions of the water turbine and the double-fed fan in the complex frequency domain, and the rotational inertia of the water turbine, obtaining the frequency response of each generator grid-connected node in the wind-water combined system. Carrying out linearization processing on the network power flow equation based on a direct current power flow method only according to