In order to solve the multiple power extreme value point problem caused by system frequency splitting during wireless energy transmission at short distances a transmission model of the system is established.With the c...In order to solve the multiple power extreme value point problem caused by system frequency splitting during wireless energy transmission at short distances a transmission model of the system is established.With the comprehensive consideration of the resonance frequency load parameters and the coupling between coils the internal factors of frequency splitting and boundary conditions are discussed.The results show that under the condition of the fixed load the higher the natural resonance frequency the easier the frequency splitting. As the frequency splitting occurs the frequency of the maximum power transfer is no longer with the natural resonance frequency which can make the system unstable and the transfer power more difficult to control. Therefore a decreasing-frequency method is proposed to avoid the system frequency splitting. And decreasing the system resonance frequency can make the system successfully withdraw the frequency splitting area at a short-distance range.Under the fixed load condition the transmission power of the system can be increased by 400% and the transmission efficiency is reduced by only 14% which greatly improves the transmission performance of the system.展开更多
In order to address the issues that the magnetic coupled resonant wireless power transfer （MCR-WPT） system is sensitive to the resonant frequency and that transmission power is difficult to control with the non-resi...In order to address the issues that the magnetic coupled resonant wireless power transfer （MCR-WPT） system is sensitive to the resonant frequency and that transmission power is difficult to control with the non-resistive load in the MCR-WPT, a single-side regulation scheme for frequency and transmission power online is proposed, which is based on the inherent constraint relationships the among system parameters in the primary side. Thus, the communication between the primary side and the secondary side is avoided. First, the transfer models of resistance-capacitance load and resistance- inductance load are established, respectively. Next, the relationship between the input voltage phasor and the input current phasor is used to recognize the load property and value. Then, the coaxial rotation of the stepper motor and the rotating vacuum variable capacitor is conducted to unify resonant frequency both in the primary side and the secondary side. Finally, the regulations of both frequency and amplitude of input voltage are made to guarantee transmission power under a new resonant frequency point the same as the one when the only pure resistance part of load is accessed under the former resonant frequency point. Both simulation and experimental results indicate that the proposed regulation scheme can track remnant frequency and maintain transmission power constant.展开更多
近来,无线电能传输技术受到了越来越广泛的关注,同时,该技术也被尝试应用于电动汽车以实现电动汽车的无线充电。与能量在自由空间传播相比,电动汽车无线充电时的电磁环境有很大不同,而电磁安全问题也变得日益突出。基于上述问题,首先分...近来,无线电能传输技术受到了越来越广泛的关注,同时,该技术也被尝试应用于电动汽车以实现电动汽车的无线充电。与能量在自由空间传播相比,电动汽车无线充电时的电磁环境有很大不同,而电磁安全问题也变得日益突出。基于上述问题,首先分析了该领域的安全限制与标准问题;其次通过仿真分析了电动汽车充电时的参数变化、电磁环境以及对人体的影响;最后通过电动汽车试验来验证仿真结果,系统实现了约为3.5 k W的能量传输。该研究可为无线充电电动汽车的优化设计提供理论依据。展开更多
基金Scholarship Award for Excellent Doctoral Student granted by Ministry of Education of Chinathe Scientific Innovation Research of College Graduates in Jiangsu Province(No.CXZZ11-0150)+1 种基金the National Natural Science Foundation of China(No.51177011)the National High Technology Research and Development Program of China(863 Program)(No.2012AA050210)
文摘In order to solve the multiple power extreme value point problem caused by system frequency splitting during wireless energy transmission at short distances a transmission model of the system is established.With the comprehensive consideration of the resonance frequency load parameters and the coupling between coils the internal factors of frequency splitting and boundary conditions are discussed.The results show that under the condition of the fixed load the higher the natural resonance frequency the easier the frequency splitting. As the frequency splitting occurs the frequency of the maximum power transfer is no longer with the natural resonance frequency which can make the system unstable and the transfer power more difficult to control. Therefore a decreasing-frequency method is proposed to avoid the system frequency splitting. And decreasing the system resonance frequency can make the system successfully withdraw the frequency splitting area at a short-distance range.Under the fixed load condition the transmission power of the system can be increased by 400% and the transmission efficiency is reduced by only 14% which greatly improves the transmission performance of the system.
基金The National Natural Science Youth Foundation of China(No.51507032)the Natural Science Foundation of Jiangsu Province(No.BK20150617)the Fundamental Research Funds for the Central Universities
文摘In order to address the issues that the magnetic coupled resonant wireless power transfer （MCR-WPT） system is sensitive to the resonant frequency and that transmission power is difficult to control with the non-resistive load in the MCR-WPT, a single-side regulation scheme for frequency and transmission power online is proposed, which is based on the inherent constraint relationships the among system parameters in the primary side. Thus, the communication between the primary side and the secondary side is avoided. First, the transfer models of resistance-capacitance load and resistance- inductance load are established, respectively. Next, the relationship between the input voltage phasor and the input current phasor is used to recognize the load property and value. Then, the coaxial rotation of the stepper motor and the rotating vacuum variable capacitor is conducted to unify resonant frequency both in the primary side and the secondary side. Finally, the regulations of both frequency and amplitude of input voltage are made to guarantee transmission power under a new resonant frequency point the same as the one when the only pure resistance part of load is accessed under the former resonant frequency point. Both simulation and experimental results indicate that the proposed regulation scheme can track remnant frequency and maintain transmission power constant.
文摘近来,无线电能传输技术受到了越来越广泛的关注,同时,该技术也被尝试应用于电动汽车以实现电动汽车的无线充电。与能量在自由空间传播相比,电动汽车无线充电时的电磁环境有很大不同,而电磁安全问题也变得日益突出。基于上述问题,首先分析了该领域的安全限制与标准问题;其次通过仿真分析了电动汽车充电时的参数变化、电磁环境以及对人体的影响;最后通过电动汽车试验来验证仿真结果,系统实现了约为3.5 k W的能量传输。该研究可为无线充电电动汽车的优化设计提供理论依据。
