死区下含被动开关事件的全半混合MMC全模态等效建模方法OA

Power electronic devices enable controllable energy conversion between the AC and DC sides of the full-half hybrid modular multilevel converter(MMC)through its switching events.Considering the switching delay of the device and the propagation delay of the drive circuit,a dead-time should be introduced into the conduction signal of the switch.During the dead-time,the passive switching event dominates the circuit state,and the switching event is no longer fixed at the integer multiple time point of the simulation step.The working state of the sub-module will produce uncontrolled dynamic switching within a single simulation step.Aiming at the problem that the passive switching event does not match the fixed simulation steps,this paper proposes an all modes of full-half hybrid MMC equivalent modeling method that can accurately locate the passive switching event.The Thevenin equivalent modeling based on the ideal switching device is used for the mode dominated by the active switching event,and the virtual diode is introduced for the mode dominated by the passive switching event.The branch section is used to write the electrical branch information of the valve section so as to connect each mode in series.The detailed model and equivalent model of the switch control signal with dead zone are built on the PSCAD simulation platform.The simulation results show that the proposed model has high accuracy and acceleration effect.