Multi-switch synchronous isolation driving circuit with over-current protection

Abstract

The invention provides a multi-switch synchronous isolation driving circuit with over-current protection, and the circuit is used for synchronously driving a plurality of semiconductor switch tubes. The circuit comprises a control circuit which is used for generating and outputting an analog signal; a primary side driving circuit which is electrically connected with the control circuit and is usedfor converting the analog signal into a bipolar pulse signal; a magnetic isolation transformer which is provided with a primary side winding electrically connected with the primary side driving circuit, a plurality of cross-core magnetic rings connected to the primary side winding in series in an isolation manner, and a secondary side winding wound on the cross-core magnetic rings, and is used for transmitting the bipolar pulse signal; a secondary side driving control circuit which is electrically connected with a secondary side winding of the magnetic isolation transformer and is used for receiving the bipolar pulse signal and generating an isolation driving signal, wherein the primary side driving circuit is used for generating the bipolar pulse signal with adjustable pulse width, phaseand frequency, and the secondary side driving control circuit comprises a driving module and an overcurrent protection module.

Description

technical field [0001] The invention belongs to the technical field of pulse power, and in particular relates to a multi-switch synchronous isolation drive circuit with overcurrent protection. Background technique [0002] IGBT has the advantages of low driving power, low conduction voltage, large current capacity, and high withstand voltage, and is currently the mainstream semiconductor switching device. However, the current flow and withstand voltage capability of a single switch tube is still limited. When high voltage or high current is required, multiple IGBT or MOSFET switch tubes are usually used in series or in parallel, so multiple switch tubes need to be driven synchronously. However, the working potentials of different switching tubes are different, so the driving signals of the switching tubes also need to be isolated. [0003] Common isolation drive schemes include magnetic isolation drive, optical fiber or optocoupler isolation drive. The cost of optical fibe...

AI Technical Summary

Problems solved by technology

The above relationship exists because as the saturated conduction voltage drop decreases, the impedance of the IGBT also decreases, and the short-circuit current increases at the same time. The power consumption during the short-circuit increases with the square of the current, resulting in a rapid decrease in the short-circuit withstand time.

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