A Highly Efficient Single-phase Transformerless H-bridge Inverter for Reducing Leakage Ground Current in Photovoltaic Grid-connected System

作者：Azri Maaspaliza^*; Abd Rahim Nasrudin; Abd Halim Wahidah

来源：Electric Power Components and Systems, 2015, 43(8-10): 928-938.

DOI：10.1080/15325008.2014.981897

• leakage ground current
• inverter efficiency
• common-mode voltage
• transformerless H-bridge inverter

In this article, the performance of the split-capacitor H-bridge topology as a single-phase transformerless photovoltaic inverter is studied. By connecting the midpoint of its two series DC-link capacitors to the ground, the split-capacitor H-bridge is able to clamp the common-mode voltage of the system, effectively suppressing leakage ground current. To overcome the issue of capacitor voltage balancing, a simple balancing circuit and its control are introduced. The operation modes, common-mode voltage, and leakage ground current characteristics of the split-capacitor H-bridge topology are discussed, subsequently validated using both simulation and experimental tests. Comparison with a conventional transformerless H-bridge topology proves the superiority of the split-capacitor H-bridge topology in terms of leakage ground current and efficiency.

• 出版日期2015-6-15