Low-switching-loss model prediction control method based on single-phase grid-connected inverter

• Main Authors: GAN WEI, JI HONGCHAO, XU BO, YANG XINGWU
• Format: Patent
• Language: English
• Published: 09.09.2015
• 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 low-switching-loss model prediction control method based on a single-phase grid-connected inverter, comprising the following steps: (1) judging the direction of reference current, and selecting the switching state of an inverter according to the result of judgment; (2) acquiring an alternating-current output voltage vector of the inverter in the current switching state; (3) calculating the predicated value of grid-connected current according to a discrete state model of the single-phase grid-connected inverter; (4) acquiring the minimum value of a voltage vector evaluation index function and a corresponding voltage vector; (5) calculating the control error of adjacent moment, judging whether the control error is within a limited range, keeping the switching state output at a previous moment if the control error is within a limited range, and selecting the switching state output corresponding to the minimum value of the voltage vector evaluation index function at the current moment if the control error is not within a limited range; and (6) controlling the inverter based on the switching state acquired in step (5). Compared with the prior art, the method of the invention has the advantages of high stability, high inverter efficiency, low switching loss, and the like.