提出一族基于反向耦合电感的非隔离双向直流变换器(bi-directional DC converter,BDC),通过引入反向耦合电感,利用电感感应电势阻断不工作MOSFET的体二极管,消除了传统双向变换器中开关管寄生体二极管的反向恢复问题;通过反向耦合电感...提出一族基于反向耦合电感的非隔离双向直流变换器(bi-directional DC converter,BDC),通过引入反向耦合电感,利用电感感应电势阻断不工作MOSFET的体二极管,消除了传统双向变换器中开关管寄生体二极管的反向恢复问题;通过反向耦合电感与滤波电感等效电路的分析,将反向耦合电感与滤波电感用一个同向耦合电感代替,提出一族基于PCI的非隔离双向直流变换器。所提出的变换器控制与传统单向变换器相同,不需要专门的软启动电路,兼顾了较高变换效率、控制简单和高可靠性。给出拓扑推演过程,详细分析拓扑工作原理,并通过实验验证理论分析的正确性。展开更多
为了研究VDMOS器件体二极管在反向恢复过程中的失效机理,详细分析了600 V VDMOS器件体二极管的工作过程,采用TCAD模拟软件研究了体二极管正向导通和反向恢复状态下的载流子密度分布及温度分布情况.模拟结果表明,VDMOS器件的体二极管在...为了研究VDMOS器件体二极管在反向恢复过程中的失效机理,详细分析了600 V VDMOS器件体二极管的工作过程,采用TCAD模拟软件研究了体二极管正向导通和反向恢复状态下的载流子密度分布及温度分布情况.模拟结果表明,VDMOS器件的体二极管在正向导通时,器件终端区同样会贮存大量的少数载流子,当体二极管从正向导通变为反向恢复状态时,贮存的少数载流子会以单股电流的形式被抽取,使得VDMOS器件中最靠近终端位置的原胞中的pbody区域温度升高,从而导致该区域寄生三极管基区电阻增大、发射结内建电势降低,最终触发寄生三极管开启,造成VDMOS器件失效.分析结果与实验结果一致.展开更多
The various configurations of multilevel inverter involve the use of more numbers of switching devices, energy storage devices and/or unidirectional devices. Each switching unit necessitates the add-on driver circuit ...The various configurations of multilevel inverter involve the use of more numbers of switching devices, energy storage devices and/or unidirectional devices. Each switching unit necessitates the add-on driver circuit for proper functionality. Cascaded H-Bridge Multilevel Inverter requires overlapped switching pulses for the switching devices in positive and negative arms of the bridge which may lead to short circuit during the device failure. This work addresses the problems in different configurations of multilevel inverter by using reduced number of switching and energy storage devices and driver circuits. In the present approach Single Switch is used for each stair case positive output and single H-Bridge for phase reversal. Driver circuits are reduced by using the property of body diode of the MOSFET. Switching pulses are generated by Arduino Development Board. The circuit is simulated using Matlab. More so, through experimental means, it is physically tested and results are analyzed for the 5-step inverter and thereby simulation is fully validated. Consequently, cycloconverter operation of the circuit is simulated using Matlab. Moreover, half bridge configuration of the multilevel inverter is also analyzed for high frequency induction heating applications.展开更多
SiC MOSFET体二极管双极退化是由材料缺陷导致的退化现象,严重影响器件的可靠性,目前没有统一的试验方法,影响了器件的推广和应用。从加电模式、加电条件、试验时间和失效判据4个方面对体二极管双极退化可靠性试验方法进行了研究,并编...SiC MOSFET体二极管双极退化是由材料缺陷导致的退化现象,严重影响器件的可靠性,目前没有统一的试验方法,影响了器件的推广和应用。从加电模式、加电条件、试验时间和失效判据4个方面对体二极管双极退化可靠性试验方法进行了研究,并编制了体二极管双极退化可靠性试验方法草案。展开更多
文摘提出一族基于反向耦合电感的非隔离双向直流变换器(bi-directional DC converter,BDC),通过引入反向耦合电感,利用电感感应电势阻断不工作MOSFET的体二极管,消除了传统双向变换器中开关管寄生体二极管的反向恢复问题;通过反向耦合电感与滤波电感等效电路的分析,将反向耦合电感与滤波电感用一个同向耦合电感代替,提出一族基于PCI的非隔离双向直流变换器。所提出的变换器控制与传统单向变换器相同,不需要专门的软启动电路,兼顾了较高变换效率、控制简单和高可靠性。给出拓扑推演过程,详细分析拓扑工作原理,并通过实验验证理论分析的正确性。
文摘为了研究VDMOS器件体二极管在反向恢复过程中的失效机理,详细分析了600 V VDMOS器件体二极管的工作过程,采用TCAD模拟软件研究了体二极管正向导通和反向恢复状态下的载流子密度分布及温度分布情况.模拟结果表明,VDMOS器件的体二极管在正向导通时,器件终端区同样会贮存大量的少数载流子,当体二极管从正向导通变为反向恢复状态时,贮存的少数载流子会以单股电流的形式被抽取,使得VDMOS器件中最靠近终端位置的原胞中的pbody区域温度升高,从而导致该区域寄生三极管基区电阻增大、发射结内建电势降低,最终触发寄生三极管开启,造成VDMOS器件失效.分析结果与实验结果一致.
文摘The various configurations of multilevel inverter involve the use of more numbers of switching devices, energy storage devices and/or unidirectional devices. Each switching unit necessitates the add-on driver circuit for proper functionality. Cascaded H-Bridge Multilevel Inverter requires overlapped switching pulses for the switching devices in positive and negative arms of the bridge which may lead to short circuit during the device failure. This work addresses the problems in different configurations of multilevel inverter by using reduced number of switching and energy storage devices and driver circuits. In the present approach Single Switch is used for each stair case positive output and single H-Bridge for phase reversal. Driver circuits are reduced by using the property of body diode of the MOSFET. Switching pulses are generated by Arduino Development Board. The circuit is simulated using Matlab. More so, through experimental means, it is physically tested and results are analyzed for the 5-step inverter and thereby simulation is fully validated. Consequently, cycloconverter operation of the circuit is simulated using Matlab. Moreover, half bridge configuration of the multilevel inverter is also analyzed for high frequency induction heating applications.