Study on Power Loss in Transformerless Grid-Connected Inverter

Abstract:

Efficiency is becoming increasingly important in grid connected photovoltaic inverter design. Transformer in grid connected inverter system is removed to improve the efficiency of system. Traditional Power loss calculation methods often neglected ripple current effects. However, Photovoltaic inverters seldom operate at the maximum rated power due to variation of irradiation. Therefore, the ripple current effects on component power loss on the light load condition should not be neglected. The paper analyzes the work principle of a transformerless grid connected inverter in detail, and establishes a mathematical model of component power loss which includes ripple current effects. An experimental prototype is made and experiment results verify the correctness of the 2éQ: theoretical analysis"theoretical analysis.

• Periodical: Advanced Materials Research (Volume 787)
• Pages: 626-631
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.787.626
• Online since: September 2013
• Authors: Hui Shu
• Keywords: Grid-Connected Inverter, Ripple Current, Transformerless

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