Method of converting a direct current voltage from a source of direct current voltage, more specifically from a photovoltaic source of direct current voltage, into a alternating current voltage

US7411802B2 · kind B2 · utility

Assignee

• SMA Solar Technology AG · DE

Inventors

• Matthais Victor · Kassel, DE
• Frank Greizer · Kaufungen, DE
• Sven Bremicker · Baumbach, DE
• Uwe Hübler · Oderberg, DE

Key dates

• Filing date: Jun 16, 2005
• Grant date: Aug 12, 2008
• Expiry date: Jun 16, 2025

Classification

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

Abstract

An inverter is devised to avoid high-frequency voltages at input terminals and to allow good efficiency thanks to its simple and cost-optimized circuit layout. This is achieved by a method of converting a direct current voltage, more specifically from a photovoltaic source of direct current voltage, into an alternating current voltage at a frequency through a bridge circuit comprising switching elements (V1-V 4) and free-wheeling elements (D1-D4), said switching elements (V1-V4) being on the one side gated at the frequency and on the other side clocked at a high clock rate, a direct current voltage circuit, an alternating current voltage circuit and a plurality of free-wheeling phases being provided. It is provided that, during the free-wheeling phases, the alternating current voltage circuit is decoupled from the direct current voltage circuit by means of a switching element disposed in the direct current voltage circuit, a free-wheeling current flowing through one of the free-wheeling elements (D1) in the bridge circuit when in the decoupled state.