Optimized junction temperature fluctuation suppression technique for SiC MOSFETs in a wireless charging system

The problem of SiC MOSFET junction temperature fluctuation in wireless charging systems must be addressed immediately. The existing temperature fluctuation suppression technique requires a large number of additional switches and capacitors. This study further optimizes the temperature fluctuation tracking suppression (TFTS) strategy. This method realizes closed-loop temperature adjustment and greatly simplifies the system structure. In addition, an optimized TFTS (OTFTS) strategy combined with an optimized proportional-integral-derivative control method is proposed to solve integral saturation and the subsequent control instability phenomenon. Then, a 5.5 kW experimental system is built. Results show that the OTFTS strategy eliminates 17.9 degrees C junction temperature fluctuation on the basis of reducing the hardware cost. It also has a good dynamic response and junction temperature fluctuation suppression effect.