Grid-Connected Photovoltaic Multistring PCS With PV Current Variation Reduction Control

• Published in: IEEE transactions on industrial electronics (1982) 2009-11, Vol.56 (11), p.4381-4388
• Main Authors: Kwon, Jung-Min, Kwon, Bong-Hwan, Nam, Kwang-Hee
• Format: Article
• Language: English
• Subjects: Algorithms; Control systems; Controllers; Inverters; Maximum power; Maximum power point tracking (MPPT); Measurement errors; Microcontrollers; multistring; Personal communication networks; Photovoltaic cells; Photovoltaic systems; Power conditioning; power conditioning system (PCS); Power harmonic filters; Prototypes; Reduction; Solar cells; Solar power generation
• ISSN: 0278-0046; 1557-9948
• DOI: 10.1109/TIE.2008.2010293

In this paper, a grid-connected photovoltaic (PV) multistring power conditioning system with PV input current reduction control is proposed. An improved maximum power point tracking (MPPT) method for the multistring converter is suggested. The suggested MPPT algorithm tracks the maximum power point even though measurement errors exist. To reduce the PV current variation introduced by the inverter, a PV current variation reduction control is suggested. This PV current variation reduction control reduces the PV current variation without additional components. The low current variation reduces the filter size and improves the MPPT efficiency. All algorithms and controllers are implemented on a single-chip microcontroller. Experimental results obtained on a 3-kW prototype show high performance such as a MPPT efficiency of 99.7%, an almost unity power factor, a power efficiency of 96.7%, and a total harmonic distortion of 2.0%.