Reverse blocking IGBT shortcircuit protecting circuit, method and system thereof, and storage medium

Abstract

The invention provides a reverse blocking IGBT shortcircuit protecting circuit, a method and a system thereof, and a storage medium. The reverse blocking IGBT shortcircuit protecting circuit comprisesthe components of a high-resistance resistor which is connected with the collector electrode of a reverse blocking IGBT; wherein the high-resistance resistor has the resistance which is higher than apreset value; a voltage difference detecting unit which is connected with the high-resistance resistor and is used for performing absolute value conversion on voltage; a comparator circuit which is connected the signal output end of the voltage difference detecting unit and is used for performing analog-to-digital conversion on the output voltage of the voltage difference detecting unit; a driving and detecting chip of which the overcurrent signal end is connected with the comparator circuit; and a DSP chip which is connected with the output end of the driving and detecting chip; wherein thereference ground end of the driving and detecting chip is connected with the output ground end of the voltage difference detecting unit. The driving end of the driving and detecting ship is connectedwith the driving circuit of the voltage difference detecting unit. Shortcircuit protection of the reverse blocking IGBT is realized, and damage of a driving protecting circuit is prevented.

Description

technical field [0001] The present invention relates to the technical field of protection circuits, more specifically, to a reverse resistance type IGBT short-circuit protection circuit, method and system, and a computer-readable storage medium. Background technique [0002] The IGBT short-circuit protection circuit in the prior art is as figure 1 Shown, by using the detection diode D to achieve. Its working process is briefly described as follows: [0003] (1) When the IGBT is turned off, the diode D blocks the influence of the IGBT collector high voltage on the detection circuit. [0004] (2) When the IGBT is turned on, the current source passes through the diode D, and the IGBT forms a loop. Since the tube voltage drop Vce is very low when the IGBT is saturated and turned on, the non-inverting terminal of the comparator is clamped at a low potential and does not output a short-circuit fault signal. [0005] (3) When the IGBT is short-circuited, it will quickly exit sa...

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Problems solved by technology

[0005] (3) When the IGBT is short-circuited, it will quickly exit saturation and Vce will rise

When the above short-circuit protection method of IGBT is applied to the reverse resistance IGBT figure 2 As shown, the reverse resistance IGBT works under the reverse blocking condition, the emitter potential is higher than the collector, forming a current loop in the figure, resulting in a negative potential at point A, which will damage the drive protection circuit

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