Simulation model's design of a new converter transformer based on multi-coil coupling

In order to study the electromagnetic transient course and electric parameter's variation rules when the new converter transformer operates under normal or all kinds of external and internal faulty and saturated core conditions, develop suitable protection schemes for the new converter transformer, it is essential to design simulation models to research accordingly. Based on the coupling concept, according to the special winding wiring mode of the new converter transformer, with a finite element simulation software, multi-coil coupling module of Matlab is used to design the normal and internal faulty simulation model of the new converter transformer separately, and a nonlinear inductance branch is designed to simulate the characteristic of saturated core of the new converter transformer. The correctness of the simulation models designed by this paper are verified by simulation results. The physical concept of the simulation models designed by this paper is very clear and the designing course is simple. The calculation precision is comparative high, and the methods which designing the simulation model of the new converter transformer can be used to design and analyze normal, external and internal faulty and inrush current simulation models of arbitrary complex multi-winding transformers in actual projects.