针对现有无线能量和信号同步传输(Simultaneous wireless power and signal transmission,SWPST)系统存在功率密度低、系统结构复杂及能量与信号互扰等问题,提出一种基于单管逆变的高频注入式SWPST系统。首先,给出了基于单管逆变的SWPS...针对现有无线能量和信号同步传输(Simultaneous wireless power and signal transmission,SWPST)系统存在功率密度低、系统结构复杂及能量与信号互扰等问题,提出一种基于单管逆变的高频注入式SWPST系统。首先,给出了基于单管逆变的SWPST系统结构,详细分析了系统的工作原理及P^(#)型单管逆变电路的软开关工作特性,构建了能量传输通道和信号传输通道的等效电路模型,并给出了系统参数对信号传输速率和能量传输增益的影响关系;然后,通过对系统参数对能量通道与信号通道相互干扰的电压增益分析,提出了抑制干扰、提升信号传输增益的系统参数优化设计方法,实现了信号的双向传输;最后,搭建了120 W试验平台,对系统的能量传输特性、信号传输性能及互扰特性进行了测试与验证。试验结果表明,在保证恒流输出特性的同时,实现了240 kbit/s的信号传输速率,误码率为零,系统最高效率达88.7%,验证了理论分析的正确性与有效性。展开更多
传统移相控制下,无线电能传输(Wireles power transfer,WPT)系统输出功率宽范围调节时逆变器开关管易丢失零电压开关(Zero voltage switching,ZVS)状态,导致逆变器切换损耗增大甚至损坏。阶跃脉冲调制(Stepped Pulse Modulation)是一种...传统移相控制下,无线电能传输(Wireles power transfer,WPT)系统输出功率宽范围调节时逆变器开关管易丢失零电压开关(Zero voltage switching,ZVS)状态,导致逆变器切换损耗增大甚至损坏。阶跃脉冲调制(Stepped Pulse Modulation)是一种低输出纹波调制方法,可实现宽负载范围内的ZVS运行。但是,该调制方法包含有限状态机等环节,不易采用传统的机理建模访求进行建模,给控制器设计带来困难。在Simulink电路的基础上,基于数据驱动方法辨识了无线电能传输在阶跃脉冲调制下传递函数模型,并基于该模型设计内模控制器。实验表明,基于Simulink电路仿真方法获取采样数据,能够有效解决实物实验在某些场景下难以获取实验数据的难题,获得满意的辨识模型。同时,基于辨识模型设计的内模控制器,能够精确估计不同控制参数下的系统控制性能,满足了阶跃脉冲调制无线电能传输输出电压闭环控制的性能需求。展开更多
目前水下无线电能传输(wireless power transfer,WPT)系统电池负载端电压等级较低,为有效提升功率密度及直流电压利用率,同时降低高频逆变环节电压电流应力,最为有效的方式是在系统初级引入高频降压式直流变换环节。为此,本文在系统初...目前水下无线电能传输(wireless power transfer,WPT)系统电池负载端电压等级较低,为有效提升功率密度及直流电压利用率,同时降低高频逆变环节电压电流应力,最为有效的方式是在系统初级引入高频降压式直流变换环节。为此,本文在系统初级引入隔离型高频双管正激变换器,考虑到传统稳定性分析方法的局限性,拟采用适用于高频系统的模值分析法对直流变换器动态特征展开分析。仿真与实验结果表明,该方法可使水下WPT系统初级直流变换器稳定性能得到显著提升,具有一定的工程应用价值。展开更多
In this paper, we propose the decode-and-forward(DF) based bidirectional wireless information and power transfer(BWIPT) in two-hop relay systems, where the bidirectional relay can decode and forward information from t...In this paper, we propose the decode-and-forward(DF) based bidirectional wireless information and power transfer(BWIPT) in two-hop relay systems, where the bidirectional relay can decode and forward information from the user to the access point(AP), and assist the wireless power transfer from the AP to the user. To maximize the information rate from the user to the AP, we derive the closed form expression of the optimal power splitting(PS) factor, and the time allocation scheme to obtain the optimal time switching(TS) factor. Simulation results show that for both PS and TS protocols, the proposed DF based bidirectional relay systems can improve the information rate as compared with the amplify-and-forward(AF) based bidirectional relay systems.展开更多
There are lots of factors that can influence the wireless charging efficiency in practice, such as misalignment and air-gap difference, which can also change all the charging parameters. To figure out the relationship...There are lots of factors that can influence the wireless charging efficiency in practice, such as misalignment and air-gap difference, which can also change all the charging parameters. To figure out the relationship between those facts and system, this paper presents a serial-parallel compensated(SPC) topology for electric vehicle/plug-in hybrid electric vehicle(EV/PHEV) wireless charger and provides all the parameters changing with corresponding curves. An ANSYS model is built to extract the coupling coefficient of coils. When the system is works at constant output power, the scan frequency process can be applied to wireless power transfer(WPT) and get the resonant frequency. In this way, it could determine the best frequency for system to achieve zero voltage switching status and force the system to hit the maximum transmission efficiency. Then frequency tracking control(FTC) is used to obtain the highest system efficiency. In the paper, the designed system is rated at 500 W with 15 cm air-gap, the overall efficiency is 92%. At the end, the paper also gives the consideration on how to improve the system efficiency.展开更多
文摘针对现有无线能量和信号同步传输(Simultaneous wireless power and signal transmission,SWPST)系统存在功率密度低、系统结构复杂及能量与信号互扰等问题,提出一种基于单管逆变的高频注入式SWPST系统。首先,给出了基于单管逆变的SWPST系统结构,详细分析了系统的工作原理及P^(#)型单管逆变电路的软开关工作特性,构建了能量传输通道和信号传输通道的等效电路模型,并给出了系统参数对信号传输速率和能量传输增益的影响关系;然后,通过对系统参数对能量通道与信号通道相互干扰的电压增益分析,提出了抑制干扰、提升信号传输增益的系统参数优化设计方法,实现了信号的双向传输;最后,搭建了120 W试验平台,对系统的能量传输特性、信号传输性能及互扰特性进行了测试与验证。试验结果表明,在保证恒流输出特性的同时,实现了240 kbit/s的信号传输速率,误码率为零,系统最高效率达88.7%,验证了理论分析的正确性与有效性。
文摘传统移相控制下,无线电能传输(Wireles power transfer,WPT)系统输出功率宽范围调节时逆变器开关管易丢失零电压开关(Zero voltage switching,ZVS)状态,导致逆变器切换损耗增大甚至损坏。阶跃脉冲调制(Stepped Pulse Modulation)是一种低输出纹波调制方法,可实现宽负载范围内的ZVS运行。但是,该调制方法包含有限状态机等环节,不易采用传统的机理建模访求进行建模,给控制器设计带来困难。在Simulink电路的基础上,基于数据驱动方法辨识了无线电能传输在阶跃脉冲调制下传递函数模型,并基于该模型设计内模控制器。实验表明,基于Simulink电路仿真方法获取采样数据,能够有效解决实物实验在某些场景下难以获取实验数据的难题,获得满意的辨识模型。同时,基于辨识模型设计的内模控制器,能够精确估计不同控制参数下的系统控制性能,满足了阶跃脉冲调制无线电能传输输出电压闭环控制的性能需求。
文摘目前水下无线电能传输(wireless power transfer,WPT)系统电池负载端电压等级较低,为有效提升功率密度及直流电压利用率,同时降低高频逆变环节电压电流应力,最为有效的方式是在系统初级引入高频降压式直流变换环节。为此,本文在系统初级引入隔离型高频双管正激变换器,考虑到传统稳定性分析方法的局限性,拟采用适用于高频系统的模值分析法对直流变换器动态特征展开分析。仿真与实验结果表明,该方法可使水下WPT系统初级直流变换器稳定性能得到显著提升,具有一定的工程应用价值。
基金supported in part by the National Natural Science Foundation of China(No.61401330,No.61371127)
文摘In this paper, we propose the decode-and-forward(DF) based bidirectional wireless information and power transfer(BWIPT) in two-hop relay systems, where the bidirectional relay can decode and forward information from the user to the access point(AP), and assist the wireless power transfer from the AP to the user. To maximize the information rate from the user to the AP, we derive the closed form expression of the optimal power splitting(PS) factor, and the time allocation scheme to obtain the optimal time switching(TS) factor. Simulation results show that for both PS and TS protocols, the proposed DF based bidirectional relay systems can improve the information rate as compared with the amplify-and-forward(AF) based bidirectional relay systems.
基金Department of Technology in Shaanxi Province,China(No.2016GY-126)
文摘There are lots of factors that can influence the wireless charging efficiency in practice, such as misalignment and air-gap difference, which can also change all the charging parameters. To figure out the relationship between those facts and system, this paper presents a serial-parallel compensated(SPC) topology for electric vehicle/plug-in hybrid electric vehicle(EV/PHEV) wireless charger and provides all the parameters changing with corresponding curves. An ANSYS model is built to extract the coupling coefficient of coils. When the system is works at constant output power, the scan frequency process can be applied to wireless power transfer(WPT) and get the resonant frequency. In this way, it could determine the best frequency for system to achieve zero voltage switching status and force the system to hit the maximum transmission efficiency. Then frequency tracking control(FTC) is used to obtain the highest system efficiency. In the paper, the designed system is rated at 500 W with 15 cm air-gap, the overall efficiency is 92%. At the end, the paper also gives the consideration on how to improve the system efficiency.
