A kind of igbt parallel dynamic current sharing circuit and control method

Abstract

The invention provides an IGBT shunt-wound dynamic current-sharing circuit and a control method. The circuit comprises a global driving delay control module, at least two shunt-wound IGBTs, and local feedback control circuits and delayed information transceiving circuits which are arranged in one-to-one correspondence with the IGBTs; the emitters of the IGBTs are connected with the input ends of the corresponding local feedback control circuits and the delayed information transceiving circuits; the input end of the global driving delay control module is connected with the output ends of the delayed information transceiving circuits separately while the output end of the global driving delay control module is connected with the input ends of the local feedback control circuits separately; the output ends of the local feedback control circuits are connected with the gate electrodes of the corresponding IGBTs; the local feedback control circuits are used for adjusting the magnitude of driving signals sent to the corresponding IGBTs; and the global driving delay control module is used for obtaining switch-on and switch-off time differences of different IGBTs according to the collected switch-on and switch-off time of each IGBT, and adjusting the time for sending reference signals according to the time differences.

Description

technical field [0001] The invention relates to the technical field of power electronics, in particular to an IGBT parallel dynamic current sharing circuit and a control method. Background technique [0002] Insulated Gate Bipolar Transistor (IGBT) combines the advantages of power field effect transistor (MOSFET) and power transistor, and has the advantages of high input impedance, low driving power, and good switching characteristics. It is an ideal fully controlled device. It has been widely used in power electronic equipment. However, for high-voltage and high-power power electronic equipment, the current level of a single IGBT cannot meet the requirements of the equipment, which makes it an effective choice to connect multiple IGBTs in parallel as a basic unit. [0003] The key to the parallel application of IGBTs is to ensure the current balance of each IGBT during switching dynamics, so as to avoid serious overcurrent damage. The reasons for the uneven current balanc...

AI Technical Summary

Problems solved by technology

The inconsistency of the IGBT's own parameters will lead to the switching characteristics of each parallel IGBT (such as turn-on and turn-off delays, the current change rate di during turn-on and turn-off processes) ce / dt) is different, which leads to the unbalanced dynamic current of each parallel switch tube

In addition, the difference in the delay time of the driving signal will cause a higher dynamic current on the IGBT that is turned on first and turned off first, resulting in the problem of dynamic uneven current sharing of IGBTs in parallel.

Therefore, the core problem of IGBT parallel application is the dynamic current sharing problem

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