Neutral-point voltage balance control improvement method for three-level bidirectional DCDC converter

• Main Authors: BI HONGDA, LIU JINJING, GUO QILIANG, ZOU CUNZUO, XU MINGXIA
• Format: Patent
• Language: Chinese; English
• Published: 29.11.2022
• 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 relates to a neutral-point voltage balance control improvement method for a three-level bidirectional DCDC converter. The method comprises the following steps: respectively sampling an upper bridge arm support capacitor voltage, a lower bridge arm support capacitor voltage and an inductive current; selecting a switching tube for adjusting the duty ratio according to the relation between the voltage of the upper bridge arm support capacitor and the voltage of the lower bridge arm support capacitor and the direction of the inductive current, and controlling the balance of the neutral-point voltage of the three-level bidirectional DCDC converter; the inductive current can also select an input current or an output current in a DCDC converter circuit to control the balance of the neutral-point voltage of the three-level bidirectional DCDC converter; by reasonably selecting the switch tube for adjusting the duty ratio, the problem that the neutral-point voltage is out of control due to factors such as