Research And Design Of High-power IGBT Driven Circuit Based On Digital Control

Since the 1980s,IGBTs have been widely used in various power conversion devices due to their advantages such as small drive power,fast switching speed,and low saturation voltage.The drive protection circuit is the most important part of controlling the turn-on and turn-off of the IGBT,and it is related to whether the conversion device composed of IGBT can operate safely,reliably,and efficiently.In order to improve these problems,this thesis designs an IGBT digital drive protection circuit with intelligent fault management system based on digital chip CPLD.The main research work is as follows:First,the mechanism of IGBT is studied.Including the basic structure,working principle,basic characteristics,SOA;combined with the voltage and current changes in the IGBT conduction pass,a detailed analysis of the conduction pass;a short-term failure of the three short circuit forms and hazards were studied in detail;The cause and mechanism of failure were analyzed in detail.Secondly,the basic requirements and basic principles of IGBT drive protection circuit were analyzed.The design method of the driving part,protection part and DC-DC power supply part of the IGBT drive protection circuit is studied in detail.Then the digital control IGBT drive protection hardware circuit is designed,and the overall drive protection circuit hardware architecture is built.Under this architecture,detailed hardware circuit design and parameter calculations were performed for CPLD core modules,serial communication modules,gate driver modules,isolation modules,fault protection modules,and isolated DC-DC power supply modules.According to the requirements of the drive protection circuit,the simulation test of the partial drive protection hardware circuit was completed.Finally,the Quartz II tool was used to develop the IGBT drive protection circuit program.According to the designed drive protection hardware circuit,the gate driver,serial communication program and fault protection program were designed respectively,and the sequential and logic simulations of the normal and faulted programs were performed;the codes and fault signals fed back under different faults were coded.At the time of going low,an intelligent fault management system was developed,and communication between the system and the CPLD was tested using a serial communication program.An experimental test platform based on double pulse was set up,and the designed digital drive protection circuit was tested and analyzed.The test results show that the digital drive protection circuit designed in this paper not only has a perfect fault protection mechanism,but also can realize the designation of the IGBT drive pulse dead time and the intelligent management of IGBT faults.