Modeling and Analysis of Crosstalk Phenomenon for Switching Devices in Current-Source Inverter

In this article, a new crosstalk phenomenon is clarified for the drivers of power switches in current-source inverter (CSI). The key is to develop a high-frequency equivalent circuit for the phase leg of CSI, based on which a predictive model is proposed for judging the voltage spikes of crosstalk between the gate and source of silicon-carbide mosfet . Unlike the crosstalk phenomenon mainly caused by dv/dt in voltage-source inverter, the voltage spikes are caused by di/dt in CSI, which usually occur when the switching actions occur in the neighbor phase leg. The influencing factors of crosstalk voltage spikes in CSI are further analyzed. It has been disclosed that the value of crosstalk voltage spike is inversely proportional to the impedance of gate resistor. The derived model of crosstalk voltage spikes will be of important significance for the design of gate drivers for CSI. Both simulation and experiments are given to verify the effectiveness of the proposed predictive model and theoretical analysis.