A 50 MHz 1.8/0.9 V dual-mode buck DC-DC converter is proposed in this paper. A dual-mode control for high-frequency DC-DC converter is presented to enhance the conversion efficiency of light-load in this paper. A nove...A 50 MHz 1.8/0.9 V dual-mode buck DC-DC converter is proposed in this paper. A dual-mode control for high-frequency DC-DC converter is presented to enhance the conversion efficiency of light-load in this paper. A novel zero-crossing detector is proposed to shut down synchronous rectification transistor NMOS when the inductor crosses zero, which can decrease the power loss caused by reverse current and the trip point is adjusted by regulating IBIAS （BIAS current）. A new logic control for pulse-skipping modulation loop is also presented in this paper, which has advantages of simple structure and low power loss. The proposed converter is realized in SMIC 0.18μm 1-poly 6-metal mixed signal CMOS process. With switching loss, conduction loss and reverse current related loss optimized, an efficiency of 57% is maintained at 10 mA, and a peak efficiency of 71% is measured at nominal operating conditions with a voltage conversion of 1.8 to 0.9 V.展开更多
装设故障限流装置是解决日益严重的电网短路电流超标问题的有效技术措施之一。基于智能快速断路器技术、短路电流过零点精确相控开断技术研制了一套330 k V开关型零损耗电网故障限流装置。该装置采用模块化设计方法,在正常运行时损耗为...装设故障限流装置是解决日益严重的电网短路电流超标问题的有效技术措施之一。基于智能快速断路器技术、短路电流过零点精确相控开断技术研制了一套330 k V开关型零损耗电网故障限流装置。该装置采用模块化设计方法,在正常运行时损耗为零,短路故障发生20 ms内,可将80 k A及以下的短路电流限制在系统断路器安全开断水平。装置成功在330 k V线路上通过了带电、挂网运行和2次人工单相瞬时短路试验,验证了装置满足安全性、有效性和可靠性的要求。展开更多
针对煤矿井下选择性漏电保护的问题,着重围绕零序功率方向性原理对该问题进行了研究,并结合DSP(Digital Signal Processor)技术给出了一种基于TMS320LF2407A芯片的零序电压、电流相位比较方案。这一方案是通过过零触发电路捕捉零序电压...针对煤矿井下选择性漏电保护的问题,着重围绕零序功率方向性原理对该问题进行了研究,并结合DSP(Digital Signal Processor)技术给出了一种基于TMS320LF2407A芯片的零序电压、电流相位比较方案。这一方案是通过过零触发电路捕捉零序电压、电流的过零点,然后在软件上来比较零序电压、电流之间的相位关系,根据漏电故障支路与非故障支路中零序电压、电流之间相位的不同,从而实现漏电保护的选择性。同时为了验证过零触发电路的可行性,使用电子电路仿真软件Multisim9进行了触发电路的硬件仿真。最后根据选择性漏电保护的实现过程给出了软件设计流程图以及试验数据分析。展开更多
基金supported by the National Natural Science Foundation of China(Nos.61404043,61401137)the Key Laboratory of Infrared Imaging Material and Detectors,Shanghai Institute of Technical Physics,CAS(Nos.IIMDKFJJ-13-06,IIMDKFJJ-14-03)the Fundamental Research Funds for the Central University(No.2015HGZX0026)
文摘A 50 MHz 1.8/0.9 V dual-mode buck DC-DC converter is proposed in this paper. A dual-mode control for high-frequency DC-DC converter is presented to enhance the conversion efficiency of light-load in this paper. A novel zero-crossing detector is proposed to shut down synchronous rectification transistor NMOS when the inductor crosses zero, which can decrease the power loss caused by reverse current and the trip point is adjusted by regulating IBIAS （BIAS current）. A new logic control for pulse-skipping modulation loop is also presented in this paper, which has advantages of simple structure and low power loss. The proposed converter is realized in SMIC 0.18μm 1-poly 6-metal mixed signal CMOS process. With switching loss, conduction loss and reverse current related loss optimized, an efficiency of 57% is maintained at 10 mA, and a peak efficiency of 71% is measured at nominal operating conditions with a voltage conversion of 1.8 to 0.9 V.
文摘装设故障限流装置是解决日益严重的电网短路电流超标问题的有效技术措施之一。基于智能快速断路器技术、短路电流过零点精确相控开断技术研制了一套330 k V开关型零损耗电网故障限流装置。该装置采用模块化设计方法,在正常运行时损耗为零,短路故障发生20 ms内,可将80 k A及以下的短路电流限制在系统断路器安全开断水平。装置成功在330 k V线路上通过了带电、挂网运行和2次人工单相瞬时短路试验,验证了装置满足安全性、有效性和可靠性的要求。
文摘针对煤矿井下选择性漏电保护的问题,着重围绕零序功率方向性原理对该问题进行了研究,并结合DSP(Digital Signal Processor)技术给出了一种基于TMS320LF2407A芯片的零序电压、电流相位比较方案。这一方案是通过过零触发电路捕捉零序电压、电流的过零点,然后在软件上来比较零序电压、电流之间的相位关系,根据漏电故障支路与非故障支路中零序电压、电流之间相位的不同,从而实现漏电保护的选择性。同时为了验证过零触发电路的可行性,使用电子电路仿真软件Multisim9进行了触发电路的硬件仿真。最后根据选择性漏电保护的实现过程给出了软件设计流程图以及试验数据分析。
