Hybrid MMC electromagnetic transient simulation constant admittance rapid model construction method and system

The invention belongs to the field of power electronic power conversion device modeling and simulation, and the method comprises the steps: carrying out the discretization of a half-bridge sub-module and a full-bridge sub-module of a hybrid MMC, and obtaining a half-bridge sub-module discrete circuit and a full-bridge sub-module discrete circuit; according to the Thevenin equivalence principle, the half-bridge sub-module discrete circuit and the full-bridge sub-module discrete circuit are equivalent to a Thevenin equivalent circuit with the impedance Rsmeq and the voltage source esmeq connected in series; a trapezoidal method is adopted to discretize a hybrid MMC bridge arm inductor, and the hybrid MMC bridge arm inductor is equivalent to a circuit in which an impedance RL and a voltage source eLeq are connected in series; and connecting the bridge arm inductance discrete circuit with the Thevenin equivalent circuit of each sub-module in series, and performing equivalent processing on series impedance and a v