Hybrid MMC starting charging method

• Main Authors: LUO YONGJIE, ZHANG LIANSHENG, PU YI, XIONG XIAOFU, OUYANG JINXIN, SONG YONGHUI
• Format: Patent
• Language: Chinese; English
• Published: 23.07.2019
• Subjects: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC,OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWERSUPPLY SYSTEMS; CONTROL OR REGULATION THEREOF; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION

The invention discloses a hybrid MMC starting charging method, which solves the technical problem of overmodulation of a converter. The method comprises the following steps of: 1, pre-charging all half-bridge sub-modules and all full-bridge sub-modules; step 2, when the pre-charging voltage is reached, entering a step 3; step 3, entering a controlled charging stage 1: calculating a reference number nrefu of an upper bridge arm input sub-module; if the nrefu is greater than or equal to 0 and less than or equal to N1, entering a step 4; if <->N1<nrefu<=N1+N2, entering the step 5; if cN2<=nrefu<0, entering a step 6; step 4, inputting nrefu half-bridge sub-modules into the upper bridge arm, and inputting nrefl half-bridge sub-modules into the lower bridge arm; step 5; putting N1 half-bridge sub-modules into the upper bridge arm, and putting <->nrefl full-bridge sub-modules to output a positive level, and inputting <->nrefl full-bridge sub-modules into a lower bridge arm to output a negative level; step 6, inputti