Leakage current suppression dual-modulation wave modulation method based on non-isolated photovoltaic inverter

• Main Authors: MA JUNPENG, BI JIEFAN, WANG SHUNLIANG, HAN XUE, JIAO NING, YAO LINGJUN
• Format: Patent
• Language: Chinese; English
• Published: 23.12.2022
• 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; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTINGELECTRIC POWER; CONTROL OR REGULATION THEREOF; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION; SYSTEMS FOR STORING ELECTRIC ENERGY

The invention discloses a leakage current suppression dual-modulation wave modulation method based on a non-isolated photovoltaic inverter. The method comprises the following steps: establishing a non-isolated photovoltaic grid-connected L-type filtering three-level inverter topological structure, simplifying the inverter system topological structure, constructing an L-type filtering leakage current model, and deducing a common-mode voltage and leakage current approximate expression; then, when the CBPWM carrier in-phase lamination method is adopted, the change of the working state of the inverter is analyzed, and the change comprises the change condition of common-mode voltage; according to an analysis result, on the basis that it is guaranteed that the change condition of the output voltage uAB in one carrier period is kept unchanged when the sizes of modulation waves are different, namely on the basis that the output voltage of the inverter is kept unchanged, the change condition of the common-mode voltage