Inverter, power generation system and method of operating a power generation system

US8717719B2 · kind B2 · utility

Assignee

• SMA Solar Technology AG · DE

Inventors

• Matthias Victor · Kassel, DE
• Frank Greizer · Kaufungen, DE

Key dates

• Filing date: May 11, 2011
• Grant date: May 6, 2014
• Expiry date: Apr 20, 2032

Classification

• Technology area (CPC H): Electricity
• CPC primary: H02H3/16
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

The invention relates an inverter that may be set up as part of a power generation system for the connection of a number of substrings, which, using DC switches, can be connected to each other in series into a string and with the inverter. The inverter includes a bridge circuit to transform the power generated by the string comprising series-connected substrings into a grid-compatible AC voltage and to feed the power into a grid. The inverter also includes a ground fault detector arranged on the AC side of the bridge circuit for ground fault monitoring of the string. A controller connected to the ground fault detector controls the DC switches so that in case of a ground fault, a complete decoupling of the connection of the string from the bridge circuit and a separation of the string into potential-free substrings is performed. A method of operating such a power generation system is also described.