Dead zone setting method of sic MOSFET three-phase two-level converter

Abstract

The invention discloses a dead zone setting method for a SiC MOSFET three-phase two-level converter, comprising the following steps: obtaining the output current at the midpoint of the bridge arm of each phase; judging the polarity of the output current, and determining according to the polarity of the output current The initiative of the upper bridge switch tube and the lower bridge switch tube of the phase bridge arm; obtain the parameter information of the SiC MOSFET and its driver board, and calculate the pre-dead time and post-dead time according to the parameter information; turn on the active switch tube The pre-dead time is set to N times the pre-dead time, where 1.5

Description

technical field [0001] The invention relates to the technical field of converters, in particular to a dead zone setting method for a SiC MOSFET three-phase two-level converter. Background technique [0002] With the emergence of wide bandgap semiconductor devices such as SiC MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor, Metal-Oxide-Semiconductor Field-Effect Transistor), power electronic equipment can have more advantages: higher operating voltage, larger High power, smaller size, higher power density, higher switching frequency, lower loss, higher operating temperature, etc. These advantages make SiC MOSFET power electronic devices more suitable for medium and low voltage applications such as electric locomotives, electric aircraft, new energy power generation, and microgrids. Among them, the SiC MOSFET three-phase two-level converter is currently the most promising SiC MOSFET converter due to its simple topology and control strategy. However, although the us...

AI Technical Summary

Problems solved by technology

However, although the use of SiC MOSFETs in three-phase two-level converters can bring many advantages, it brings difficulties to its dead zone setting

[0003] Although the traditional fixed dead zone setting scheme can still ensure the reliability of the SiC MOSFET three-phase two-level converter, it will bring a large loss and output voltage loss

There are two main dead zone setting schemes currently applied to SiC MOSFET converters: the first one is to minimize the dead zone setting scheme by taking full advantage of the advantage that the SiC MOSFET channel impedance is smaller than the diode impedance. Although the scheme can reduce the freewheeling loss of the diode, it may cause a large loss of the output capacitance of the SiC MOSFET and reduce the reliability of the system; the second scheme reduces the freewheeling loss of the diode and the output capacitance of the SiC MOSFET at the same time. loss, but requires an additional dead zone selection circuit, increasing the cost and complexity of the system

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