Harmonic suppression method applied to grid-connected photovoltaic inverter

• Main Authors: ZHOU FEI, LEI TAO, LIU JINGDOU, CHEN NING, YI DI, WANG LIAN, JIA LIMIN, TONG YIBIN
• Format: Patent
• Language: Chinese; English
• Published: 23.04.2014
• 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; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERATION; REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGYGENERATION, TRANSMISSION OR DISTRIBUTION; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE

The invention relates to the technical field of grid-connected photovoltaic power generation, especially to the technical field of a harmonic suppression method applied to a grid-connected photovoltaic inverter. According to the invention, suppression of harmonic current is realized, and the problem that output current of a present grid-connected photovoltaic inverter contains lots of harmonic current is solved. Acquired voltages and currents in a static three-phase coordinate system are converted to a two-phase rotating coordinate system, and active and reactive components are respectively controlled in the two-phase rotating coordinate system. An active shaft adopts a double closed-loop control strategy: an outer loop controls DC voltage and adopts a PI controller, and an inner loop controls active current and adopts a PI parallel resonance (PR) controller. A reactive shaft adopts a single closed-loop control strategy to control power factor of the grid-connected photovoltaic inverter and adopts a PI parall