Multi-rate electromechanical transient simulation method and system based on LCC-HVDC

The invention discloses a multi-rate electromechanical transient simulation method and system based on LCC-HVDC, and relates to the technical field of electric power automation, and the method comprises the steps: enabling an LCC-HVDC system to employ a time-varying dynamic phasor to simulate an electromagnetic process according to a converter station topological structure, enabling other parts of a power grid to employ electromechanical transient simulation, and carrying out the electromechanical transient simulation according to the electromechanical transient simulation. Constructing a rectification side simplified model and an inversion side simplified model; constant current control is adopted for a rectification side, constant voltage control is adopted for an inversion side, so that a control model is constructed, a simulation step length is calculated, and transient simulation is performed on the system; and performing calculation on transient simulation by utilizing a node calculation equation, perfo