sic MOSFET short-circuit detection circuit based on drain-source conduction voltage integration

Abstract

This application proposes a SiC MOSFET short circuit detection circuit based on drain-source conduction voltage integration, which relates to the field of power electronics technology, including: the drain and source of the SiC MOSFET whose primary side of a voltage transformer (PT) is connected in parallel in the power electronic circuit ; One end of the integral resistance (R) is connected to one end of the secondary side of the voltage transformer (PT), the other end of the integral resistance (R), one end of the integral capacitor (C), and one end of the switch tube (S1) are connected to the inverting input end of the operational amplifier ; The other end of the secondary side of the voltage transformer (PT) is grounded with the same-phase input end of the operational amplifier, the other end of the integrating capacitor (C) and the other end of the switching tube (S1) are connected with the output end of the operational amplifier, and the output end of the operational amplifier It is connected with the inverting input terminal of the comparator, and the non-inverting input terminal of the comparator is connected with the reference voltage. In this way, the short circuit of the SiC MOSFET can be quickly detected and a short circuit signal can be output, and the short circuit protection action is faster when the bus voltage is higher, and the reliability of the power electronic system can be improved.

Description

technical field [0001] The present application relates to the technical field of power electronics, in particular to a SiC MOSFET (Silicon Carbide Semiconductor Field Effect Transistor) short-circuit detection circuit based on integration of drain-source conduction voltage. Background technique [0002] SiC MOSFET has great application potential in high temperature, high frequency, high voltage and high power, etc., and short-circuit capability is one of the key issues of SiC MOSFET. Under the same withstand voltage condition, SiC MOSFET has better performance than traditional Si MOSFET and SiIGBT. Shorter short circuit withstand time. [0003] The research results show that the short circuit withstand time of SiC MOSFET decreases with the increase of DC bus voltage and gate drive voltage, especially when the DC bus voltage is high, the huge power loss caused by short circuit makes the junction temperature of SiC MOSFET rapidly rise, causing irreversible damage and thermal ...

AI Technical Summary

Problems solved by technology

While this method is accurate and fast, it adds additional power loss and is only suitable for short-circuit protection of discrete components

[0007] 3) Gate voltage detection, according to the gate charge characteristics of SiC MOSFET, hard switching faults can be detected by detecting gate-source voltage and gate charge, but load faults cannot be detected, and when the bus DC voltage is low, the detection will also be reduced precision

Images