A High-Speed IGBT Switching Characteristic Detection System Based on SoC and FPGA Acceleration

As an important condition parameter, turn-off time of insulated gate bipolar transistor (IGBT) has a close relationship with junction temperature and device health state. Researches show that it is effective to monitor the health state of IGBT by measuring turn-off time of each switching and junction temperature. However, traditional methods of calculating turnoff time either directly measure collector-emitter voltage or indirectly measure gate side parameters, which may have risks on safety and problems of complexity. In order to overcome these problems, in this paper, an IGBT switching characteristic detection system based on system-on-chip (SOC) is proposed, which takes IGBT turn-off time and output current as switching characteristic, and features in high-speed calculation (in microsecond level) of turn-off time in real time. The system uses a non-contact turn-off time calculating method to monitor the health state of IGBT in an online way and improves its performance by field programmable gate array (FPGA) acceleration on ZYNQ SoC. Compared with the existing technology, it has the advantages of high security, high performance and simple engineering implementation. Finally, the feasibility of the system is verified by experiments.

I. Introduction

Insulated Gate Bipolar Transistor (IGBT), as an important power electronic switching device, is widely used in various power converter systems in electric vehicle drive, power generation and transmission, and many other industries. Researches show that the failures of power electronic devices account for most of the failures of power converter systems and IGBT faults account for 42% [1]. With the increasing concern on IGBT reliability， condition monitoring (CM) has become an effective technique to prevent IGBT failures. By monitoring the health state of IGBT module, the CM system can give a timely warning before the failure [2]-[3], so that catastrophic accidents are prevented and the cost of operation as well as maintenance are reduced.