Multi-stage SiC-MOSFET drive circuit and control method

Abstract

The invention provides a multi-stage SiC-MOSFET drive circuit and a control method. The multi-stage SiC-MOSFET drive circuit comprises an SiC-MOSFET, a first-stage drive circuit, a detection circuit, a second-stage drive circuit and a control circuit of the second-stage drive circuit, wherein the first-stage drive circuit is used for providing drive current to turn on the SiC-MOSFET to work; the detection circuit is used for collecting voltage dynamic waveforms in the turn-on process of the SiC-MOSFET; the control circuit comprises a waveform shaping module, a counting module and a control module which are in signal connection in sequence; the control circuit comprises a waveform shaping module, a counting module and a control module which are in signal connection in sequence. According to the invention, rapid switching-on of the SiC-MOSFET is realized through the two-stage driving circuit, the voltage peak during switching-on is eliminated, and the voltage oscillation during switching-off is reduced; and voltage dynamic parameters in the opening process are obtained, and then the secondary driving circuit is adjusted through the control module to supplement the driving current, so that stable driving voltage is provided.

Description

technical field [0001] The invention relates to the field of driving technology of third-generation wide bandgap semiconductor silicon carbide devices, in particular to a multi-level SiC-MOSFET driving circuit and a control method. Background technique [0002] One of the future development trends of the power electronics industry is to use higher switching frequency to obtain more compact system design. In the application of high switching frequency and high power, SiC devices have obvious advantages, which makes SiC-MOSFET in 5G base stations , industrial power supply, photovoltaic, charging pile, uninterruptible power supply system and energy storage and other application scenarios continue to increase the demand. [0003] SiC (silicon carbide) is a third-generation semiconductor. Compared with similar products, SiC has significant advantages in key parameters such as bandgap width, breakdown electric field strength, saturated electron drift rate, thermal conductivity, an...

AI Technical Summary

Problems solved by technology

Compared with Si devices, SiC devices are different in materials and structures, and there are also some differences in device characteristics. Therefore, the existing Si-based power device drive circuits cannot be used to directly drive SiC-based power devices. The latter The drive circuit needs to be specially designed

[0005] In practical applications, the simplest and most common way to adjust the switching characteristics of SiC-MOSFET is to add passive devices in the driving circuit to achieve passive driving. The passive driving circuit has the largest The advantage lies in its simple structure and low cost, but there are also many disadvantages, such as the inability to take into account the SiC-MOSFET switching delay time, switching loss, current or voltage spikes and EMI

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