Research On Control And Driving Method Of RC-IGBT Bidirectional DC/DC Converter

Power electronic power devices have been widely used in important fields such as manufacturing,energy,and national defense.They are the core devices of various high-quality and high-precision power supply products,and are also the cornerstone and important guarantee for realizing electric energy conversion.Reverse-conducting IGBT(RC-IGBT)is a new power device that integrates IGBT and fast recovery diode on the same substrate.It can accommodate more RC-IGBT chips under the same package size and can meet the needs of small power supply products.The demand for high power density and high power has broad application prospects.However,due to the special structure of RC-IGBT,there is a body diode turn-on and turn-off process,and the application of bidirectional DC/DC converters will introduce new losses.Among them,the optimal design for the control and drive of such converters has not been able to draw a comparison.A good solution,so studying the optimized driving method of the RC-IGBT bidirectional DC/DC converter can provide an effective solution to the characteristics of the body diode of the RC-IGBT in the scenario of the bidirectional DC / DC converter.Reliable operation is of great significance.The main research of this article is as follows:(1)Compare the difference between the conventional IGBT bidirectional DC/DC converter and the RC-IGBT DC/DC converter,and analyze the RC-IGBT bidirectional DC / DC converter under two operating modes(Buck / Boost)The working state of each RC-IGBT.The dual-mode control strategy of the RC-IGBT bidirectional DC/DC converter is proposed,and the double hysteresis current direction detection link is introduced to effectively eliminate the interference of burrs and harmonics and realize the working mode.The reliable judgment of the state realizes the reliable operation of this type of converter in two operating modes(Buck / Boost).Secondly,the small signal model of the RC-IGBT bidirectional DC/DC converter is established,and the appropriate control parameters are selected.Finally The system was simulated to verify the correctness of relevant modal analysis and control methods.(2)Aiming at the problem of the turn-on and turn-off process of the RC-IGBT body diode,the driving characteristics and requirements of the RC-IGBT body diode turn-on and turn-off in the bidirectional DC/DC converter are analyzed,and an RC-IGBT is proposed The three-level low-power full-duty-cycle driving strategy solves the driving problem of RC-IGBT applied to bidirectional DC/DC converters.In the diode turn-on process,the gate-emitter negative level drive is used to reduce the turn-on loss of the RC-IGBT body diode;during the diode turn-off process,a desaturation pulse is introduced to reduce the turn-off loss of the RC-IGBT in diode mode;To avoid misoperation,introduce a 0V buffer voltage during desaturation.At the same time,a full-duty-cycle asymmetric modulation method is designed to eliminate the dead zone effect during the desaturation process.Finally,the principle of finite state machine is used to realize RC-IGBT modal identification and switching,and the overall driving scheme design of RC-IGBT low power consumption full duty cycle is given.(3)Designed the main circuit and parameters of the RC-IGBT bidirectional DC/ DC converter,the hardware circuit of the control system and its software control program,and built the RC-IGBT bidirectional DC/DC converter experimental prototype and test platform,The proposed dual-modal control strategy and three-level low-power full-duty-cycle driving strategy were experimentally verified.