Injection current mode sic MOSFET active drive circuit

Abstract

The invention discloses an injection current type SiC MOSFET active driving circuit. The injection current type SiC MOSFET active driving circuit comprises a driving push-pull circuit, a driving resistor, a detection circuit, a pulse generation circuit and an amplification output circuit; the detection circuit is used for detecting the driving voltage of the driving push-pull circuit so as to judge whether a SiC MOSFET enters a grid current reduction stage or not according to the driving voltage; The pulse generation circuit is used for generating a pulse with a preset width according to the driving voltage; And the amplification output circuit is used for amplifying the pulse and injecting current into the grid electrode of the SiC MOSFET. The active driving circuit provided by the embodiment of the invention can effectively inhibit the peak and oscillation of the drain-source voltage when the SiC MOSFET is turned off, and improves the reliability problem and the electromagnetic interference problem caused by the peak and oscillation of the drain-source voltage of the SiC MOSFET on the premise of not sacrificing the advantages of the SiC device.

Description

technical field [0001] The invention relates to the technical field of power electronics, in particular to an injection current type SiC MOSFET active drive circuit. Background technique [0002] Due to the limitations of its material properties, silicon-based power electronic devices have been unable to meet the high performance requirements of semiconductor devices in the field of power electronics today. Based on this, wide-bandgap semiconductor materials represented by silicon carbide (SiC) came into being. Compared with silicon (Si) devices, SiC devices have lower on-resistance, faster switching speed, and higher breakdown. These excellent characteristics make SiC devices have significant advantages in high frequency and high power density. However, the faster switching speed of SiC devices also brings challenges to its application. Due to the excessive switching speed of SiC devices, it will generate a large voltage and current change rate, and there are stray inducta...

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Problems solved by technology

By optimizing the PCB layout and reducing the stray inductance of the line, this method has higher requirements for hardware design; increasing the driving resistance can also suppress spikes and oscillations to a certain extent, but increasing the driving resistance will increase the switching delay and slow down Switching speed increases switching loss, which sacrifices the advantages of SiC devices; in addition, snubber circuits and active clamps can also suppress voltage spikes and oscillations to a certain extent, but additional components such as capacitors or inductors in the power circuit will increase Losses on the power circuit side, reducing the efficiency of the converter

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