Research On High Reliability Drive And Communication Technology Of High Power IGBT Modules

With the development of semiconductor devices, power electronics have been widely used in various fields of the power industry. As the typical representative of power semiconductor devices, IGBT gets popular application for its excellent performance. As a result, the high-power, integration and modularity technique of power electronic devices becomes a new trend. In power electronics modular system, the technology of drive circuit and modules’ communication has great contribution to the control efficiency and reliability, which is very important to the safety of PEBB system. In this paper, the highly reliable driver circuit and communication technologies for PEBBs were studied basing on the high-power PEBB module.Firstly, the general design methods of IGBT driver circuit was presented. In order to solve the imbalance current problem in IGBT parallel application, general solutions have been studied. Then, this paper purposed some schemes to detect and protect the IGBT failures. Because the switching speed of power semiconductor devices continue increasing, the voltage spike at switching off time of PWM inverter becomes a serious problem. After indicating the shortcomings of traditional ways to reduce the switching voltage spike, a new technique on driving pulse edge modulation was purposed which is based on digital control. By using the technique in a digital-analog hybrid driver, the voltage spike of IGBTs can be reduced. It only needs to modulate the density and width of pre-pulse-train to control the slope of the driving signal which can avoid the changes of driver circuit. This method is universal and economical.In traditional PEBB systems, much more optical fibers are needed when power modules increase. And it brings many difficulties in assembling which is not good for the reliability of the PEBB system. To solve this problem, a Single-fiber ring communication method was presented in this paper. With this method, the data was transported in a pseudo-synchronous way, and the transmission time could be highly reduced. It can improve the IGBT driver’s synchronization.Finally, the half-bridge power module based on parallel IGBTs was designed, and it was applied in an H-bridge inverter. The experiment proved the validity and practicability of the methods.