针对新能源领域对开关变换器具有宽电压增益范围的要求,提出一种多模式变频宽输出LLC变换器。该变换器原边为全桥结构,副边整流器为两级倍压结构,通过控制副边开关管的导通与截止,具有3种不同的电路模式,其增益比为1∶2∶4。各种模式对...针对新能源领域对开关变换器具有宽电压增益范围的要求,提出一种多模式变频宽输出LLC变换器。该变换器原边为全桥结构,副边整流器为两级倍压结构,通过控制副边开关管的导通与截止,具有3种不同的电路模式,其增益比为1∶2∶4。各种模式对应不同的输出电压等级,采用变频控制方式,变换器可以实现50~430 V的宽输出电压范围。多种模式切换,使得变换器具有较窄的开关频率范围(65~100 k Hz)。通过合理的参数设计,变换器可以实现原边开关管零电压开通(ZVS)和副边二极管零电流关断(ZCS)。新的电路拓扑结构降低了副边二极管和副边电容的电压应力,仅为输出电压的一半。在理论和仿真分析基础上,制作了1.3 kW的实验样机。实验结果表明,该变换器可以在保证效率的同时实现宽输出电压范围,适合应用于宽输出场合。展开更多
[ Objective] The paper aimed to provide more information for effective prevention and control of clinical canine diarrhea. [ Method] 156 cases of dogs with clinical diarrhea were selected as objects to analyze the rea...[ Objective] The paper aimed to provide more information for effective prevention and control of clinical canine diarrhea. [ Method] 156 cases of dogs with clinical diarrhea were selected as objects to analyze the reasons for its diarrhea and observe the therapeutic effect. [ Result] Bacterial and viral diarrhea are major causes of canine diarrhea; The cure rate of parasitic diarrhea was high while that of viral diarrhea was poor; That probiotics and white clay combined with conventional therapies had a good therapeutic effect on canine diarrhea. [ Conclusion] It was essential to keep exploring more effective therapies to treat canine diarrhea matched with basic therapies.展开更多
文摘针对新能源领域对开关变换器具有宽电压增益范围的要求,提出一种多模式变频宽输出LLC变换器。该变换器原边为全桥结构,副边整流器为两级倍压结构,通过控制副边开关管的导通与截止,具有3种不同的电路模式,其增益比为1∶2∶4。各种模式对应不同的输出电压等级,采用变频控制方式,变换器可以实现50~430 V的宽输出电压范围。多种模式切换,使得变换器具有较窄的开关频率范围(65~100 k Hz)。通过合理的参数设计,变换器可以实现原边开关管零电压开通(ZVS)和副边二极管零电流关断(ZCS)。新的电路拓扑结构降低了副边二极管和副边电容的电压应力,仅为输出电压的一半。在理论和仿真分析基础上,制作了1.3 kW的实验样机。实验结果表明,该变换器可以在保证效率的同时实现宽输出电压范围,适合应用于宽输出场合。
基金Supported by Jiangsu Animal Husbandry and Veterinary Medicine College College-level Subjects(YB200916)"Blue Project"of Jiangsu Province Universities[Jiangsu teachers(2010),27th]
文摘[ Objective] The paper aimed to provide more information for effective prevention and control of clinical canine diarrhea. [ Method] 156 cases of dogs with clinical diarrhea were selected as objects to analyze the reasons for its diarrhea and observe the therapeutic effect. [ Result] Bacterial and viral diarrhea are major causes of canine diarrhea; The cure rate of parasitic diarrhea was high while that of viral diarrhea was poor; That probiotics and white clay combined with conventional therapies had a good therapeutic effect on canine diarrhea. [ Conclusion] It was essential to keep exploring more effective therapies to treat canine diarrhea matched with basic therapies.
