@inproceedings{StubenrauchSeligerSchmittLandsiedel2016, author = {Stubenrauch, Franz and Seliger, Norbert and Schmitt-Landsiedel, Doris}, title = {A Low Impedance Drive Circuit to Suppress the Spurious Turn-On in High Speed Wide Band-Gap Semiconductor Halfbridges}, series = {PCIM Europe 2016; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management, N{\"u}rnberg}, booktitle = {PCIM Europe 2016; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management, N{\"u}rnberg}, pages = {8}, year = {2016}, abstract = {A gate drive circuit for gallium nitride (GaN) enhancement mode (e-mode) transistors is presented, which avoids parasitic turn-on of the power devices in the halfbridge configuration. New e-mode GaN devices turn on at very low threshold voltages between 1V and 2V. This makes the transistors highly sensitive to spurious turn-on and thus reduces the required safety margin of the gate drive signals. To avoid this parasitic turn-on, a very low gate loop impedance is required. This prevents the halfbridge against bridge shorts during the switching events and guarantees stable gate drive control with increased switching efficiency. The new gate drive circuit is developed in a SPICE simulation environment and verified in a prototype setup by a double pulse test. The simulation matches very well with the experimental result and demonstrates the suppression of parasitic semiconductor turn-on with the proposed gate drive. Furthermore the dissipated switching energy is reduced, compared to a standard gate drive circuit. High DCDC converter efficiency of 98.67\% at 1kW output power is achieved by using the driving circuit for a buck converter prototype with 200kHz switching frequency.}, language = {en} } @inproceedings{StubenrauchSeligerSchmittLandsiedel2016, author = {Stubenrauch, Franz and Seliger, Norbert and Schmitt-Landsiedel, Doris}, title = {A Simplified SPICE Model for Fast Parametric Optimization of High Voltage Power Electronic Circuits in the Megahertz Range}, series = {CIPS 2016; 9th International Conference on Integrated Power Electronics Systems, N{\"u}rnberg}, booktitle = {CIPS 2016; 9th International Conference on Integrated Power Electronics Systems, N{\"u}rnberg}, pages = {6}, year = {2016}, abstract = {An accurate SPICE model is proposed in this paper to calculate the power losses of high voltage converter systems. This supports power circuit optimization in the very first design stage. The parasitic package inductances and the nonlinear voltage dependent semiconductor capacitances are taken into account. In addition the high frequency behavior of the power inductor is investigated. A detailed loss breakdown is done to analyze the main sources of power loss and their physical reasons. The simulation results of the converter waveforms and of its efficiency match very well to the experimental results. The prototype boost converter shows a top efficiency greater than 98.3 \% at a switching frequency of 1 MHz and an output voltage of 400 V at the maximum output power of 1 kW.}, language = {en} } @inproceedings{SeligerStubenrauchSchmittLandsiedel2016, author = {Seliger, Norbert and Stubenrauch, Franz and Schmitt-Landsiedel, Doris}, title = {A Parametric Layout Study of Radiated Emission from High-Frequency Half-Bridge Switching Cells}, series = {CIPS 2016 - 9th International Conference on Integrated Power Electronics Systems, N{\"u}rnberg}, booktitle = {CIPS 2016 - 9th International Conference on Integrated Power Electronics Systems, N{\"u}rnberg}, pages = {6}, year = {2016}, abstract = {We present a numerical modeling study of radiated emission from half-bridge switching cells based on the method of moments (MoM). A low loop inductance cell design enables high-speed switching of power semiconductors which is demonstrated on a prototype circuit. The layout is further optimized for low radiated emission by variation of the heat sink placement. This is achieved by the heat sink attached to the phase terminal. The performance of the structure in terms of loop impedance, electric field radiation and sensitivity to cable attachments are numerically studied. Emission peaks arising from loop resonances can be reduced by over 20 dB with damping elements in the switching cell. The improved EMI performance of the proposed structure is attributed to decoupling of the loop current from the heat sink structure.}, language = {en} }