Current-voltage （I-V） characteristics of a non-transferred DC arc plasma spray torch operated in argon at vacuum are reported. The arc voltage is of negative characteristics for a current below 200 A, fiat for a cur...Current-voltage （I-V） characteristics of a non-transferred DC arc plasma spray torch operated in argon at vacuum are reported. The arc voltage is of negative characteristics for a current below 200 A, fiat for a current between 200 A to 250 A and positive for a current beyond 250 A. The voltage increases slowly with the increase in carrier gas of arc. The rate of change in voltage with currents is about 3-4 V/100 A at a gas flow rate of about 1-1.5 V/10 standard liter per minute （slpm）. The I-V characteristics of the DC plasma torch are of a shape of hyperbola. Arc power increases with the argon flow rate. and the thermal efficiency of the torch acts in a similar way. The thermal efficiency of the non-transferred DC plasmatron is about 65-78%.展开更多
讲解了DC-DC变换器的基本工作原理,以及其中一个十分重要的使用参数——转换效率。基于转换效率的问题,仿真设计该电源需要用到电源芯片LM3150以及利用到美国设计的用来仿真的软件,WEBENCH Power Designer设置开关电源的每个元器件数值...讲解了DC-DC变换器的基本工作原理,以及其中一个十分重要的使用参数——转换效率。基于转换效率的问题,仿真设计该电源需要用到电源芯片LM3150以及利用到美国设计的用来仿真的软件,WEBENCH Power Designer设置开关电源的每个元器件数值,并综合考虑其价格、频率、精巧设计等方面的升级优化。最后通过软件仿真检验到设计出来的电源的稳定性很强,且转化效率更高。展开更多
传统桥式全波RF-DC变换电路在设计过程中忽略了二极管导通损耗,从而影响系统效率。采用了E类零电压开关(Zero Voltage Switching,ZVS)RF-DC变换电路,设计了谐振频率为8 MHz,输入功率为1.21 W的无线电力传输系统接收模块。并利用multisi...传统桥式全波RF-DC变换电路在设计过程中忽略了二极管导通损耗,从而影响系统效率。采用了E类零电压开关(Zero Voltage Switching,ZVS)RF-DC变换电路,设计了谐振频率为8 MHz,输入功率为1.21 W的无线电力传输系统接收模块。并利用multisim软件进行了仿真。结果表明,该设计方法降低了二极管导通损耗,有效避免了传统桥式全波RF-DC变换电路存在的缺陷,效率可达92%。展开更多
We developed a one-dimensional hybrid model to simulate the DC/RF combined driven capacitively coupled plasma for argon discharges. The numerical results are used to analyze the influence of the DC source on the plasm...We developed a one-dimensional hybrid model to simulate the DC/RF combined driven capacitively coupled plasma for argon discharges. The numerical results are used to analyze the influence of the DC source on the plasma density distribution, ion energy distributions （IEDs） and ion angle distributions （IADs） on both the RF and DC electrodes. The increase in DC voltage drives more high-energy ions to the electrode applied to the DC source, which makes the IEDs at the DC electrode shift towards higher energy, and the peaks in the IADs shift towards small angle regions. At the same time, it also decreases the ion energy at the RF electrode and enlarges the incident angles of the ions, which strike the RF electrode.展开更多
Combined with two-dimensional(2D)and three-dimensional(3D)finite element analysis and preliminary experimental tests,the effects of size and placement of the electromagnetic shield of the radio-frequency(RF)ion source...Combined with two-dimensional(2D)and three-dimensional(3D)finite element analysis and preliminary experimental tests,the effects of size and placement of the electromagnetic shield of the radio-frequency(RF)ion source with two drivers on plasma parameters and RF power transfer efficiency are analyzed.It is found that the same input direction of the current is better for the RF ion source with multiple drivers.The electromagnetic shield(EMS)should be placed symmetrically around the drivers,which is beneficial for the plasma to distribute uniformly and symmetrically in both drivers.Furthermore,the bigger the EMS shield radius is the better generating a higher electron density.These results will be of guiding significance to the design of electromagnetic shielding for RF ion sources with a multi-driver.展开更多
文摘Current-voltage （I-V） characteristics of a non-transferred DC arc plasma spray torch operated in argon at vacuum are reported. The arc voltage is of negative characteristics for a current below 200 A, fiat for a current between 200 A to 250 A and positive for a current beyond 250 A. The voltage increases slowly with the increase in carrier gas of arc. The rate of change in voltage with currents is about 3-4 V/100 A at a gas flow rate of about 1-1.5 V/10 standard liter per minute （slpm）. The I-V characteristics of the DC plasma torch are of a shape of hyperbola. Arc power increases with the argon flow rate. and the thermal efficiency of the torch acts in a similar way. The thermal efficiency of the non-transferred DC plasmatron is about 65-78%.
文摘讲解了DC-DC变换器的基本工作原理,以及其中一个十分重要的使用参数——转换效率。基于转换效率的问题,仿真设计该电源需要用到电源芯片LM3150以及利用到美国设计的用来仿真的软件,WEBENCH Power Designer设置开关电源的每个元器件数值,并综合考虑其价格、频率、精巧设计等方面的升级优化。最后通过软件仿真检验到设计出来的电源的稳定性很强,且转化效率更高。
文摘传统桥式全波RF-DC变换电路在设计过程中忽略了二极管导通损耗,从而影响系统效率。采用了E类零电压开关(Zero Voltage Switching,ZVS)RF-DC变换电路,设计了谐振频率为8 MHz,输入功率为1.21 W的无线电力传输系统接收模块。并利用multisim软件进行了仿真。结果表明,该设计方法降低了二极管导通损耗,有效避免了传统桥式全波RF-DC变换电路存在的缺陷,效率可达92%。
基金supported by the Scientific Foundation from Ministry of Education of China (No.N090305004)Doctor Startup Foundation Program of Liaoning Province (No.20111008)
文摘We developed a one-dimensional hybrid model to simulate the DC/RF combined driven capacitively coupled plasma for argon discharges. The numerical results are used to analyze the influence of the DC source on the plasma density distribution, ion energy distributions （IEDs） and ion angle distributions （IADs） on both the RF and DC electrodes. The increase in DC voltage drives more high-energy ions to the electrode applied to the DC source, which makes the IEDs at the DC electrode shift towards higher energy, and the peaks in the IADs shift towards small angle regions. At the same time, it also decreases the ion energy at the RF electrode and enlarges the incident angles of the ions, which strike the RF electrode.
基金supported by the Comprehensive Research Facility for Fusion Technology Program of China(No.2018-000052-73-01-001228)National Natural Science Foundation of China(No.11975263)the National Key R&D Program of China(No.2017YFE0300101)。
文摘Combined with two-dimensional(2D)and three-dimensional(3D)finite element analysis and preliminary experimental tests,the effects of size and placement of the electromagnetic shield of the radio-frequency(RF)ion source with two drivers on plasma parameters and RF power transfer efficiency are analyzed.It is found that the same input direction of the current is better for the RF ion source with multiple drivers.The electromagnetic shield(EMS)should be placed symmetrically around the drivers,which is beneficial for the plasma to distribute uniformly and symmetrically in both drivers.Furthermore,the bigger the EMS shield radius is the better generating a higher electron density.These results will be of guiding significance to the design of electromagnetic shielding for RF ion sources with a multi-driver.
