Untersuchungen an weich schaltenden DC/DC Konvertern zur Versorgung von Hochleistungs-Diodenlasern

Due to the more dynamic processes used in laser-material machining done with diode-lasers, there is a growing demand on highly dynamic current sources, with which the laser emitters can be driven. Thereby, manifold boundary conditions influence the basic system-design of the current-controlled power-electronic systems.
The industrial field of application is characterized. Different commonly used topologies of the actual state of the art are analyzed in terms of usability in this field. With the aid of simulations, the different converter concepts are compared and analyzed regarding the advantages and disadvantages.
The results are used to find possible ways of optimization, which take the boundary conditions defined by the field of application into account.
Modern SiC MOSFETs are tested for use in soft switching DC/DC-Converters. Based on experiments, the possible enhancements of the values of critical parameters, e.g. efficiency or the weight, within systems of highly dynamic output current are discussed.
An experimental comparison of the switching losses of SiC MOSFETs and conventional Si devices is done.
A new converter topology is presented, which combines advantages of the Full-Bridge Converter and the Half Bridge-Converter. The usability in highly efficient diode laser systems is shown, an experimental verification is done and a comparison with conventional concepts is depicted.