Traveling Wave Tubes(TWTs) are widely used in the radar and communications system as RF power amplifiers. A highly sophisticated power supply is required by TWT. In order to meet the severe requirements of Traveling W...Traveling Wave Tubes(TWTs) are widely used in the radar and communications system as RF power amplifiers. A highly sophisticated power supply is required by TWT. In order to meet the severe requirements of Traveling Wave Tube Amplifier(TWTA), a novel two-stage topology high voltage converter for TWTA is proposed.The converter is based on Zero-Voltage Switching and Zero-Current Switching(ZVS/ZCS) resonant techniques. The high voltage converter operation principles are investigated and major features of the converter are discussed. The power switching mode of ZVS/ZCS is obtained. The experimental results show that the converter has good soft switching characteristics. Compared to the conventional hard switched Pulse Width Modulation(PWM) techniques, the high efficiency and low ripple of the converter for TWTA are realized. The efficiency of High Voltage Electronic Power Conditioners(HV-EPC) over 93.5% under the condition of 38~46 V input voltage and 260~300 W input power. The switching frequency of first-stage(preregulator) of HV-EPC is 89 k Hz and the switching frequency of second-stage(postregulator) is 44.5 k Hz. The highest output voltage of the HV-EPC is helix voltage which is about –6.8 kV. It is especially suitable for TWTA utilized in space satellite applications due to its high switching frequency and high power density.展开更多
The folded double-ridged waveguide structure is presented and its properties used for wide-band traveling-wave tube are investigated. Expressions of dispersion characteristics, normalized phase velocity and interactio...The folded double-ridged waveguide structure is presented and its properties used for wide-band traveling-wave tube are investigated. Expressions of dispersion characteristics, normalized phase velocity and interaction impedance of this structure are derived and numerically calculated. The calculated results using our theory agree well with those obtained by using the 3D electromagnetic simulation software HFSS. Influences of the ridge-loaded area and broad-wall dimensions on the high frequency characteristics of the novel slow-wave structure are discussed. It is shown that the folded double-ridged waveguide structure has a much wider relative passband than the folded waveguide slow-wave structure and a relative passband of 67% could be obtained, indicating that this structure can operate in broad-band frequency ranges of beam-wave interaction. The small signal gain property is investigated for ensuring the improvement of bandwidth. Meanwhile, with comparable dispersion characteristics, the transverse section dimension of this novel structure is much smaller than that of conventional one, which indicates an available way to reduce the weight of traveling-wave tube.展开更多
该文对Ka波段空间行波管宽频带、高线性、高效率的慢波系统进行设计,通过动态渐变技术实现了低相位失真、高效率的指标要求。在此设计基础上研制的Ka波段空间行波管实现了宽频带(25~27 GHz)、低非线性失真(非线性相移≤40°,AM/PM≤...该文对Ka波段空间行波管宽频带、高线性、高效率的慢波系统进行设计,通过动态渐变技术实现了低相位失真、高效率的指标要求。在此设计基础上研制的Ka波段空间行波管实现了宽频带(25~27 GHz)、低非线性失真(非线性相移≤40°,AM/PM≤2.86°/d B,三阶交调≥10.39 d Bc)、高效率(总效率≥51.7%)。经数传系统测试,误码P_e优于10^(-6)的情况下C/N_0有2.4 d B裕度,满足了卫星数传系统对多通道并行传输方案的工作需求。展开更多
文摘Traveling Wave Tubes(TWTs) are widely used in the radar and communications system as RF power amplifiers. A highly sophisticated power supply is required by TWT. In order to meet the severe requirements of Traveling Wave Tube Amplifier(TWTA), a novel two-stage topology high voltage converter for TWTA is proposed.The converter is based on Zero-Voltage Switching and Zero-Current Switching(ZVS/ZCS) resonant techniques. The high voltage converter operation principles are investigated and major features of the converter are discussed. The power switching mode of ZVS/ZCS is obtained. The experimental results show that the converter has good soft switching characteristics. Compared to the conventional hard switched Pulse Width Modulation(PWM) techniques, the high efficiency and low ripple of the converter for TWTA are realized. The efficiency of High Voltage Electronic Power Conditioners(HV-EPC) over 93.5% under the condition of 38~46 V input voltage and 260~300 W input power. The switching frequency of first-stage(preregulator) of HV-EPC is 89 k Hz and the switching frequency of second-stage(postregulator) is 44.5 k Hz. The highest output voltage of the HV-EPC is helix voltage which is about –6.8 kV. It is especially suitable for TWTA utilized in space satellite applications due to its high switching frequency and high power density.
基金Project supported in part by the National Natural Science Foundation of China (Grant No. 60971038)in part by the Fundamental Research Funds for Central Universities,China (Grant No. ZYGX2009Z003)
文摘The folded double-ridged waveguide structure is presented and its properties used for wide-band traveling-wave tube are investigated. Expressions of dispersion characteristics, normalized phase velocity and interaction impedance of this structure are derived and numerically calculated. The calculated results using our theory agree well with those obtained by using the 3D electromagnetic simulation software HFSS. Influences of the ridge-loaded area and broad-wall dimensions on the high frequency characteristics of the novel slow-wave structure are discussed. It is shown that the folded double-ridged waveguide structure has a much wider relative passband than the folded waveguide slow-wave structure and a relative passband of 67% could be obtained, indicating that this structure can operate in broad-band frequency ranges of beam-wave interaction. The small signal gain property is investigated for ensuring the improvement of bandwidth. Meanwhile, with comparable dispersion characteristics, the transverse section dimension of this novel structure is much smaller than that of conventional one, which indicates an available way to reduce the weight of traveling-wave tube.
文摘该文对Ka波段空间行波管宽频带、高线性、高效率的慢波系统进行设计,通过动态渐变技术实现了低相位失真、高效率的指标要求。在此设计基础上研制的Ka波段空间行波管实现了宽频带(25~27 GHz)、低非线性失真(非线性相移≤40°,AM/PM≤2.86°/d B,三阶交调≥10.39 d Bc)、高效率(总效率≥51.7%)。经数传系统测试,误码P_e优于10^(-6)的情况下C/N_0有2.4 d B裕度,满足了卫星数传系统对多通道并行传输方案的工作需求。