Method for controlling balance of three-level inverter and direct current busbar voltage

• Main Authors: SHENG LIJUN, WEI XIAOLIANG, XIAN CHENGYU
• Format: Patent
• Language: Chinese; English
• Published: 16.02.2011
• 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 method for controlling the balance of a three-level inverter and a direct current busbar voltage. The balance control method comprises the following steps of: generating a given zero-sequence current according to a difference of a positive direct current busbar voltage and a negative direct current busbar voltage; and generating three-phase trigger pulse in a direct current control mode according to the given zero-sequence current, a three-phase given current and a three-phase feedback current, wherein the three-phase trigger pulse is used for trigging a switching tube of the inverter so as to make the three-level inverter generate a zero-sequence current, the zero-sequence current generates a direct current voltage on three capacitors respectively, and the direct current voltage is used for balancing the direct current busbar voltage. By the technical scheme, the generated three-phase trigger pulse can make the three-level inverter output an appropriate zero-sequence current, the z