Modeling and Optimization Algorithm of Coupling Noise for SiC MOSFET Active Gate Driver Considering Common-Source Inductance

The high switching speed of SiC mosfet s is limited by the coupling noise in bridge-leg configurations. Conventional methods focus on the noise introduced by the gate-drain capacitance, which is suppressed by reducing the gate impedance with the active gate driver (AGD). However, when the common-source inductance ( L s ) exists, noise spikes are not strictly increasing with gate impedance. The existing AGD parameter design methods have limited suppression effects. To fully utilize the noise suppression capability of AGD, this article constructs a noise mathematical model considering L s , where the auxiliary branch is considered as RLC in series and the main factors affecting the coupling noise are all included. Based on the model, a parameter optimization algorithm is proposed. In detail, the noise spikes at different AGD parameters are calculated with a set of extracted switching characteristics. The proposed algorithm solves the AGD parameters with optimal noise suppression by using a designed cost function. The experimental results show that the variation trends of noise spikes at different AGD parameters can be accurately calculated. Compared with the conventional methods, the proposed algorithm suppresses noise spikes to optimal values. The optimization algorithm provides a guideline for the AGD parameter design.