Soft-switching three-level inverter
The S3L inverter ( Abbreviation for Soft Switching Three Level Inverter) is a power electronic inverter with high efficiency for use especially in AC drives, as feed-in inverter in photovoltaic or wind turbines and power supplies. The circuit design was developed at the HTWG Konstanz 2009.
Operation
Inverters are used to convert DC voltage into AC voltage. Usually they are constructed using power transistors and diodes. These are operated as an electronic switch. In the usual embodiment of "hard" switching operations occur while the switching losses reduce the efficiency particularly at high values of the switching frequency. To improve at higher power inverters (from about 10 kW ) are often the so-called 3-stage design ( three level inverter ) is employed.
The S3L inverter starts from such a hard-switching 3-level inverter in T -Type version. This consisting of a few passive components relief network is added. It prevents occur simultaneously high values of voltage and current, and thus high levels of power dissipation during the switching operations. This run all switching operations " soft " from. Thus, switching losses are substantially avoided. Moreover, since working the relief network without principle related losses, the efficiency of the inverter even at high values of the switching frequency on good values.
The S3L inverter is protected by patent.