Transient synchronous stability analytic analysis method for following network type MMC (Modular Multilevel Converter) grid-connected system

The invention discloses a transient synchronous stability analytic analysis method for a network following type MMC grid-connected system, which comprises the following steps: firstly, establishing a phase-locked loop grid-connected transient synchronous stability model based on a phase-locked loop kinetic equation, then establishing a system injection power model considering saturation current control during an MMC fault period, and carrying out equivalent modeling on the MMC by using a current source; obtaining a stable equilibrium point and an unstable equilibrium point of the system according to the transient synchronous stability model; and according to an equal area rule, the influence of saturation current control, system strength and phase-locked loop parameters of the MMC on the transient synchronization stability of the system is evaluated. According to the method, the transient synchronization stability of the system can be quantitatively evaluated under the condition that system parameters are det