Avoiding reverse recovery effects in super junction MOSFET based half-bridges

摘要

For applications with a dc-link voltage in the range of 400 V and high switching frequencies, Super Junction MOSFETs are superior to standard MOSFETs due to their low on-state resistance. However, they suffer from an extensive reverse recovery effect of their intrinsic body diode. This limits their usage in hard-switching half-bridge configurations. This paper analyzes a modified half-bridge based on Super Junction MOSFETs, which offers significantly reduced reverse recovery losses while maintaining current conduction in reverse direction through the Super Junction MOSFET. Hence, the application of Super Junction MOSFETs in hard switched topologies becomes possible. Measurements of relevant voltage and current waveforms as well as the thermal distribution show the efficiency of the proposed method.