A New Method of The Active Gate Driver for Current Balancing in The Parallel MOSFET Circuits

Abstract

MOSFETs are used in electronic circuits because they have high switching efficiency. Typically, MOSFETs are wired in parallel for applications that require high power. Theoretically, this circuit can multiply the current capability of parallel MOSFETs. However, even if all the MOSFETs in a parallel circuit have the same serial number and manufacturer, they might not necessarily have the same current characteristics. This could lead to issues with current imbalances, potentially causing harm to the MOSFETs, especially under severe circumstances. This study introduces a new Active Gate Driver (AGD) technique to balance the current in a parallel MOSFET circuit. The current difference can be used to modulate each MOSFET duty cycle. Specifically, the MOSFET with the smallest current capacity is configured as the Master, while the MOSFET following it is designated as the Slave. The interrupt time value for the duty cycle of each Slave MOSFET is influenced by the current differential between the Master and Slave. Consequently, different duty cycles for the Master and Slave MOSFETs can maintain the same current level. Based on the results of experiments conducted on three MOSFETs, it is evident that the AGD approach can effectively balance the current to an optimum level.