Dynamic stability analysis based on state-space model and Lyapunov's stability criterion for SiC-MOS and Si-IGBT switching

This paper proposes a new stability evaluation method for SiC-MOS and Si-IGBT in switching transient state. This method is based on Lyapunov's stability criterion and statistics. A state-space model is established based on SiC-MOS equivalent circuit with consideration of straw parameters. The system matrix in the state-space model can be used for stability analysis by Lyapunov's stability criterion for the samples that include the parameters in system matrix. The statistical method is implemented for the stability results of the samples in device switching transient state and the unstable level which is used to descript the stability performance during transient state has been defined. From the simulation and experimentation results, the unstable level has the capability to evaluate the EMI performance for comparing the impact of parasitic parameters in design of package, module and chip, even the suitability of the application circuits to suppress device self-excited oscillation.