Accelerated Model of Ultra-large Scale MMC in Electromagnetic Transient Simulations

For the purpose of drastically reducing the computational time of modular multilevel converter based HVDC(MMC-HVDC) in electromagnetic transient simulations such as PSCAD/EMTDC and MATLAB,an accelerated model of ultra-large scale MMC is proposed based on nodal analysis method.The essence of the new model is partition of one large-scale matrix into substantial small-scale matrices,which have the equivalent equations,thus the accuracy is guaranteed and simulation is accelerated.The new model has strong generality and can be used in fault cases study of IGBTs.Series levels of MMCs in PSCAD/EMTDC validate the simulation accuracy and acceleration ratio of the new model.