Amid high penetration of renewable energy and power electronic devices

uncertainty has become one of the significant characteristics of power systems. To achieve efficient simulation of multi-type random excitations and the corresponding dynamics of electromagnetic transients (EMT)

this paper analyzes the features of stochastic EMT models and the limitation of numerical methods. On this basis

a piecewise linear interpolation method is proposed to generate pseudo-Wiener process by introducing the concept of simulation interval and the ODE representation of parameter stochastic migration process. Thus

the large step approximation of Wiener process and the low complexity solution of SDE are realized. Secondly

by using the relaxation of high-order convergence to the time step

a large-step stochastic EMT simulation algorithm based on Stratonovich integration and discontinuous Galerkin method is designed. Finally

the three-phase grid-connected VSC circuit and radial DC distribution system are taken as the test objects. The comparison of deterministic and stochastic EMT simulation trajectories

algorithm complexity

and time cost validates the efficiency and accuracy of the proposed algorithm..