A General Equivalent Modeling Method of Cascading Power Electronic Topologies

With the development of power system, power electronic devices are widely used. Electromagnetic transient simulation technology is an important means of power system analysis. Due to the limitation of high-frequency switching on the simulation step size, the efficiency of electromagnetic transient simulation is extremely low. The complex and changeable topology of power electronics leads to low versatility of the existing equivalent models. Equivalent models of common modules such as half-bridge and full-bridge have been developed by common simulation platforms, but for complex and changeable power electronic topologies, the uses can only use separated components to build models, which lacks of simulation efficiency and flexibility. So, a general equivalent modeling method suitable for cascading power electronic topologies is proposed, which not only improves the simulation efficiency by using node shrinkage, but also can construct an equivalent model for custom arbitrary topology, which improves the versatility of the equivalent modeling method. Based on the proposed general equivalent model, a simulation algorithm for cascading power electronic topologies is designed. By comparing the simulation accuracy and simulation efficiency of the general equivalent model and the detailed model, it can be verified that the proposed equivalent model can improve simulation efficiency with high simulation accuracy.