A predictive current control algorithm for the Buck-Boost DC-DC converter is presented in this paper. The continuous time model of the system is properly introduced, then, by imposing a proper PWM modulation pattern, ...A predictive current control algorithm for the Buck-Boost DC-DC converter is presented in this paper. The continuous time model of the system is properly introduced, then, by imposing a proper PWM modulation pattern, its discrete time model is achieved. This last one is successfully employed in determining the steady state locus of the Buck-Boost converter, both in CCM （continuous conduction mode） and DCM （discontinuous conduction mode）. A novel continuous time equivalent circuit of the converter is introduced too, with the aim of determining a ripple free representation of the state variables of the system, over both transient and steady state operation. Then, a predictive current control algorithm, suitable in both CCM and DCM, is developed and properly checked by means of computer simulations. The corresponding results have highlighted the effectiveness of the proposed modelling and of the predictive control algorithm, both in CCM and DCM.展开更多
微波无线输能(microwave wireless power transmission,MPT)技术应用于不易获取直流电能的场合,是研制太阳能卫星、近空间飞行器的关键技术,也可应用于无线传感器网络节点供能及环境低微微波能量的回收.比较了微带线型和共面带状线型2...微波无线输能(microwave wireless power transmission,MPT)技术应用于不易获取直流电能的场合,是研制太阳能卫星、近空间飞行器的关键技术,也可应用于无线传感器网络节点供能及环境低微微波能量的回收.比较了微带线型和共面带状线型2种典型整流天线的单元和阵列性能,提出了对接收天线和整流电路的要求;以获得最大微波波束捕获效率为目标,分析了发射天线拓扑结构及高斯削尖口径电平分布.在研究以上关键技术的基础上设计了一套C波段微波输能系统,该系统从发射端到接收端的直流-直流效率为35%.最后指出了微波无线输能技术存在的问题和未来发展方向.展开更多
本文采用频率变换原理采集输电线周围电场能量,设计了一种能量采集电路,对超级电容充电。负载阻抗呈电容性,为非线性负载,充电过程中阻抗不断变化。为实现最大输出功率传输,设计了低功耗的最大输出功率追踪(MPPT)电路,采用频率值为32.76...本文采用频率变换原理采集输电线周围电场能量,设计了一种能量采集电路,对超级电容充电。负载阻抗呈电容性,为非线性负载,充电过程中阻抗不断变化。为实现最大输出功率传输,设计了低功耗的最大输出功率追踪(MPPT)电路,采用频率值为32.768 k Hz石英晶体构成方波振荡电路,因电容电压不能突变,通过充电电流控制开关导通时间,构成电流反馈最大输出功率点追踪系统。最大输出功率追踪电路的工作电流为1.2 u A,工作电压为5 V,功耗为6 u W。实验结果表明,在充电36min时达到最大功率输出,储能电容电压的大小为0.32 V,输出功率最大为18 u W。相比于直接充电电路,最大输出功率电路的能量采集效率提高了50%。展开更多
文摘A predictive current control algorithm for the Buck-Boost DC-DC converter is presented in this paper. The continuous time model of the system is properly introduced, then, by imposing a proper PWM modulation pattern, its discrete time model is achieved. This last one is successfully employed in determining the steady state locus of the Buck-Boost converter, both in CCM （continuous conduction mode） and DCM （discontinuous conduction mode）. A novel continuous time equivalent circuit of the converter is introduced too, with the aim of determining a ripple free representation of the state variables of the system, over both transient and steady state operation. Then, a predictive current control algorithm, suitable in both CCM and DCM, is developed and properly checked by means of computer simulations. The corresponding results have highlighted the effectiveness of the proposed modelling and of the predictive control algorithm, both in CCM and DCM.
文摘微波无线输能(microwave wireless power transmission,MPT)技术应用于不易获取直流电能的场合,是研制太阳能卫星、近空间飞行器的关键技术,也可应用于无线传感器网络节点供能及环境低微微波能量的回收.比较了微带线型和共面带状线型2种典型整流天线的单元和阵列性能,提出了对接收天线和整流电路的要求;以获得最大微波波束捕获效率为目标,分析了发射天线拓扑结构及高斯削尖口径电平分布.在研究以上关键技术的基础上设计了一套C波段微波输能系统,该系统从发射端到接收端的直流-直流效率为35%.最后指出了微波无线输能技术存在的问题和未来发展方向.
文摘本文采用频率变换原理采集输电线周围电场能量,设计了一种能量采集电路,对超级电容充电。负载阻抗呈电容性,为非线性负载,充电过程中阻抗不断变化。为实现最大输出功率传输,设计了低功耗的最大输出功率追踪(MPPT)电路,采用频率值为32.768 k Hz石英晶体构成方波振荡电路,因电容电压不能突变,通过充电电流控制开关导通时间,构成电流反馈最大输出功率点追踪系统。最大输出功率追踪电路的工作电流为1.2 u A,工作电压为5 V,功耗为6 u W。实验结果表明,在充电36min时达到最大功率输出,储能电容电压的大小为0.32 V,输出功率最大为18 u W。相比于直接充电电路,最大输出功率电路的能量采集效率提高了50%。
