A flying capacitor multilevel converter system with a pre-charge unit and method to precharge capacitors in a multilevel converter system

• Main Authors: Shen, Jie, Soua, Samir, Schroeder, Stefan
• Format: Patent
• Language: English; French; German
• Published: 31.03.2021
• 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

A power converter is presented. The power converter includes at least one leg (201) operatively coupled between a first bus (214) and a second bus (216) and includes a first string (202) including a plurality of non-controllable semiconductor switches (D 1 -D 8 ), a first node (224), a second node (230), and a third node (232), where the first node (230) is coupled to a third bus (222). One or more second strings (204, 205) are provided, where each second string includes at least one fully controllable semiconductor switch (S 1 -S 4 ), and where one of the second strings (204) is coupled between the first node (224) and the third bus (222) and another second string (205) is coupled between the second node (230) and the third node (232). One or more third strings (206) are provided, where each of the one or more third strings (206) includes at least one energy storage device (C 1 ) and is coupled to the first string (202), the one or more second strings (205), or a combination thereof.