Digital Drive Technology Of High Power IGBT Based On High Speed Optical Fiber Loop Communication

Since1980s, the IGBT, as the third generation power electronic device, gets popular application in various occasions of high power for its outstanding performance. Presently, the fourth generation of IGBT has been fully developed; this rapid evolution of IGBT requires higher performance of its drive circuit and working environment in reverse. Some well sold drive module, which can meet the demands to some extent, however, let many potential consumers flinch for its excessive high price. Therefore, the paper designed a complete set of drive and protection circuit, based on fully analysis of the structure and working characteristics of IGBT and its demands on drive and protection. Aiming at the application on system level, the paper put forward a strategy of loop communication in electronic field.To realize reliably drive, double pulse test has been done on the chosen IGBT observing its performance indicators in actual circuits. Besides the paper research on the design of digital drive circuit applying programmable logic chips. After analyzing the causes and effects of the IGBT failures, a scheme of failure detection and protection circuit was purposed.For occasions in need of numerous IGBT modules, the traditional point to point communication raises the demand of optical fiber and optical fiber adapters and therefore increases cost, but aggrandizes the difficulty in wiring in the same time. Under the circumstances, the paper unprecedentedly introduces the loop communication into converter field, in which each PEBB module as well as the master controller is equipped with only two optical fiber converters, one as receiver and the other as the transmitter, communicating with external modules. This approach cuts the amount of optical fiber and its adapters tremendously, so does the workload of hardware design of master controller. On the other hand, fully analysis and calculation is provided to avoid the occurrence of IGBT driver asynchronous due to the potential asynchronous data receiving of different modules in loop communication.Finally, the paper expounds the software implementation of the drive and protection in high power IGBT modules. With FPGA of Cyclone series and CPLD of Max series of Altera Company, a complete set of digital driver circuit and protection monitoring circuit is worked out, which at the same time make the loop communication easy to realize.