提出一种适用于V2G(Vehicle tǒgrid,VZG)和电网-蓄电池储能等系统的单级双向隔离AC-DC变换器。该变换器可实现高效率、高功率密度,及能量双向传输。该文介绍该变换器的工作原理、功率传输特性,分析并设计软开关ZVS(zero voltage switch...提出一种适用于V2G(Vehicle tǒgrid,VZG)和电网-蓄电池储能等系统的单级双向隔离AC-DC变换器。该变换器可实现高效率、高功率密度,及能量双向传输。该文介绍该变换器的工作原理、功率传输特性,分析并设计软开关ZVS(zero voltage switching,ZVS)的实现,最终可在宽增益范围和全负载情况下实现软开关,并制作一台500 W的实验样机进行验证。展开更多
为了解决传统的两级式光伏交流模块PV AC module存在的结构复杂、成本高、效率低等问题,提出了一种新型PV AC module。该AC module的前级为传统的Boost变换器,完成光伏组件的最大功率点跟踪和光伏接口电压的泵升;后级采用高增益集成式...为了解决传统的两级式光伏交流模块PV AC module存在的结构复杂、成本高、效率低等问题,提出了一种新型PV AC module。该AC module的前级为传统的Boost变换器,完成光伏组件的最大功率点跟踪和光伏接口电压的泵升;后级采用高增益集成式逆变器,实现直流母线电压的泵升和并网发电功能。分析了PV AC module的系统结构,工作原理及控制策略,并通过一套250 W/40 kHz的样机仿真模型,验证了方案的可行性与理论分析的正确性。研究结果表明:该新型PV AC module具有结构简洁、控制简单、成本低、效率高等优点。展开更多
A novel topology of Integrated Boost-SEPIC (IBS) AC-DC converter using common part sharing method (CPSM) has been proposed in this paper. Conventional boost converters with bridge rectifier configuration are inefficie...A novel topology of Integrated Boost-SEPIC (IBS) AC-DC converter using common part sharing method (CPSM) has been proposed in this paper. Conventional boost converters with bridge rectifier configuration are inefficient due to limited voltage step-up ratio which may not be applicable for high step-up applications as in the case of micro generators. The proposed IBS topology is based on the common part sharing method capable of operating both for positive and negative half cycle of the input signal. Result and simulation were conducted using PSIM environment. The proposed AC-DC IBS topology eliminates the requirement of bridge rectifier achieving high efficiency (about 99%), improved power factor (0.75, leading) and lower THD (about 38.8%) which is within IEEE standard.展开更多
Aims: To assess the hearing outcome in patients who have undergone stapes surgery using polytetrafluoroethylene (PTFE) and Titanium prosthesis at 1 and 3 months post operatively. Material & Methods: Research desig...Aims: To assess the hearing outcome in patients who have undergone stapes surgery using polytetrafluoroethylene (PTFE) and Titanium prosthesis at 1 and 3 months post operatively. Material & Methods: Research design: Prospective study. Setting: ENT department, Pushpagiri Medical College. Study population: All age groups with clinical diagnosis of otosclerosis and air-bone gap more than 15 dB irrespective of sex difference. Patients with Meniere’s disease are excluded. Method: A prospective study was conducted for a period of one and a half years from January 2014 to July 2015 to find out the hearing outcome of stapes surgery in patients with otosclerosis using polytetrafluoroethylene (PTFE) and Titanium prostheses, attending our outpatient department. Results: In this study, 84.21% of ears with polytetrafluoroethylene (PTFE) and 81.81% of ears with titanium were able to achieve good results in terms of Air-Bone gap (ABG) closure (ABG Conclusion: Stapes surgery is the surgical procedure of choice for otosclerosis. In our study, a significant hearing improvement was seen in majority of cases. None of the factors considered relevant for the success of stapes surgery like age, sex, type of prosthesis appeared to affect the post-operative hearing significantly. Hence stapes surgery can be effectively used to improve hearing in otosclerosis.展开更多
文摘提出一种适用于V2G(Vehicle tǒgrid,VZG)和电网-蓄电池储能等系统的单级双向隔离AC-DC变换器。该变换器可实现高效率、高功率密度,及能量双向传输。该文介绍该变换器的工作原理、功率传输特性,分析并设计软开关ZVS(zero voltage switching,ZVS)的实现,最终可在宽增益范围和全负载情况下实现软开关,并制作一台500 W的实验样机进行验证。
文摘为了解决传统的两级式光伏交流模块PV AC module存在的结构复杂、成本高、效率低等问题,提出了一种新型PV AC module。该AC module的前级为传统的Boost变换器,完成光伏组件的最大功率点跟踪和光伏接口电压的泵升;后级采用高增益集成式逆变器,实现直流母线电压的泵升和并网发电功能。分析了PV AC module的系统结构,工作原理及控制策略,并通过一套250 W/40 kHz的样机仿真模型,验证了方案的可行性与理论分析的正确性。研究结果表明:该新型PV AC module具有结构简洁、控制简单、成本低、效率高等优点。
文摘A novel topology of Integrated Boost-SEPIC (IBS) AC-DC converter using common part sharing method (CPSM) has been proposed in this paper. Conventional boost converters with bridge rectifier configuration are inefficient due to limited voltage step-up ratio which may not be applicable for high step-up applications as in the case of micro generators. The proposed IBS topology is based on the common part sharing method capable of operating both for positive and negative half cycle of the input signal. Result and simulation were conducted using PSIM environment. The proposed AC-DC IBS topology eliminates the requirement of bridge rectifier achieving high efficiency (about 99%), improved power factor (0.75, leading) and lower THD (about 38.8%) which is within IEEE standard.
文摘Aims: To assess the hearing outcome in patients who have undergone stapes surgery using polytetrafluoroethylene (PTFE) and Titanium prosthesis at 1 and 3 months post operatively. Material & Methods: Research design: Prospective study. Setting: ENT department, Pushpagiri Medical College. Study population: All age groups with clinical diagnosis of otosclerosis and air-bone gap more than 15 dB irrespective of sex difference. Patients with Meniere’s disease are excluded. Method: A prospective study was conducted for a period of one and a half years from January 2014 to July 2015 to find out the hearing outcome of stapes surgery in patients with otosclerosis using polytetrafluoroethylene (PTFE) and Titanium prostheses, attending our outpatient department. Results: In this study, 84.21% of ears with polytetrafluoroethylene (PTFE) and 81.81% of ears with titanium were able to achieve good results in terms of Air-Bone gap (ABG) closure (ABG Conclusion: Stapes surgery is the surgical procedure of choice for otosclerosis. In our study, a significant hearing improvement was seen in majority of cases. None of the factors considered relevant for the success of stapes surgery like age, sex, type of prosthesis appeared to affect the post-operative hearing significantly. Hence stapes surgery can be effectively used to improve hearing in otosclerosis.
