Inverter, more specifically for photovoltaic plants

US7843714B2 · kind B2 · utility

Assignee

• SMA Solar Technology AG · DE

Inventors

• Sven Bremicker · Baumbach, DE
• Frank Greizer · Kaufungen, DE
• Matthias Victor · Kassel, DE

Key dates

• Filing date: Jul 31, 2008
• Grant date: Nov 30, 2010
• Expiry date: May 10, 2029

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02E10/56
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

On an inverter (1) for converting an electric direct voltage, in particular of a photovoltaic direct voltage source into an alternating voltage with a direct voltage input with two terminals (DC+, DC−) and one alternating voltage output with two terminals (AC1, AC2) and with one bridge circuit including semiconductor switching elements (S1-S6), said bridge circuit comprising one first bridge branch (Z1) including four switching elements (S1-S4) and one second bridge branch (Z2) including two additional switching elements (S5, S6) as well as a freewheeling circuit provided with additional diodes (D7, D8), the efficiency is further increased without high frequency interferences and capacitive leakage currents having the possibility to occur on the generator side. This is achieved in that a respective one of the freewheeling diodes (D7, D8) forms a freewheeling branch together with a respective one of the switching elements (S2, S3) located in the first bridge branch (Z1), said freewheeling branch carrying a freewheeling current in a condition decoupled from the direct voltage.