Wireless charging has played a crucial role in electric vehicle charging market presently.As electric vehicles will be important nodes access to the smart grid in the future,the security flow of energy and information...Wireless charging has played a crucial role in electric vehicle charging market presently.As electric vehicles will be important nodes access to the smart grid in the future,the security flow of energy and information between wireless charging infrastructure and the smart grid will directly affect the security of the smart grid.A novel secure wireless transfer method for energy and information transfer simultaneously has been represented in this paper by designing a reasonable dual-band coil for simultaneous transmission of energy and information,using improved chaotic modulation and a three times handshake protocol for encrypting energy and information between wireless charging infrastructure and the smart grid.Both the simulation and experiments show that the security of energy transmission can be effectively improved by this structure,in the premise of ensuring the power and efficiency of wireless energy transmission.展开更多
When private electric vehicles(EVs),which will be the main part of the EVs’cluster in the future,are plugged in power system by single phase power line,can result to three-phase unbalance problem of distribution netw...When private electric vehicles(EVs),which will be the main part of the EVs’cluster in the future,are plugged in power system by single phase power line,can result to three-phase unbalance problem of distribution network.In this work,a phased-controlled coordinated charging method was put forward to solve this problem.Firstly,the impacts of charging load to distribution network was analyzed based on the equivalent circuit;and then an architecture of the control method and its corresponding optimal control model were introduced.The optimal model is a multi-objective optimization model,which includes minimizing load variance of each phase and minimizing the power asymmetrical degree of three-phase load;lastly,three scenarios considering balance and unbalance cases were envisioned to verify the reasonableness of this control method based on IEEE-37 distribution network.Results show that the phased-controlled coordinated charging method can minimize the load variance as well as the negative sequence current.展开更多
Capacitive power transfer(CPT)technology is a newly emerging research focus for EV charging applications.Due to the absence of eddy current loss and light weight of the capacitive coupling metal plates,CPT technology ...Capacitive power transfer(CPT)technology is a newly emerging research focus for EV charging applications.Due to the absence of eddy current loss and light weight of the capacitive coupling metal plates,CPT technology is considered to be a promising alternative to the inductive power transfer(IPT)technology.In this paper,the recent designs of large-gap CPT systems designed for EV charging applications are summarized.And a graphical method based on Smith chart is proposed to analyze the characteristics of the compensation designs.With the design objectives graphically represented,the Smith chart can be used to visually analyze the performance of a compensation design,which could be helpful in multi-objectives design of the CPT system.The graphic features of three major design objectives on the Smith chart are investigated.Several guidelines of a good compensation design are concluded.展开更多
基金This work is supported by International Science&Technology Cooperation Program of China under contract No.2016YFE0102200.
文摘Wireless charging has played a crucial role in electric vehicle charging market presently.As electric vehicles will be important nodes access to the smart grid in the future,the security flow of energy and information between wireless charging infrastructure and the smart grid will directly affect the security of the smart grid.A novel secure wireless transfer method for energy and information transfer simultaneously has been represented in this paper by designing a reasonable dual-band coil for simultaneous transmission of energy and information,using improved chaotic modulation and a three times handshake protocol for encrypting energy and information between wireless charging infrastructure and the smart grid.Both the simulation and experiments show that the security of energy transmission can be effectively improved by this structure,in the premise of ensuring the power and efficiency of wireless energy transmission.
基金This work was supported by the national high technology research and development program of China(863 Program)(No.2011AA05A109).
文摘When private electric vehicles(EVs),which will be the main part of the EVs’cluster in the future,are plugged in power system by single phase power line,can result to three-phase unbalance problem of distribution network.In this work,a phased-controlled coordinated charging method was put forward to solve this problem.Firstly,the impacts of charging load to distribution network was analyzed based on the equivalent circuit;and then an architecture of the control method and its corresponding optimal control model were introduced.The optimal model is a multi-objective optimization model,which includes minimizing load variance of each phase and minimizing the power asymmetrical degree of three-phase load;lastly,three scenarios considering balance and unbalance cases were envisioned to verify the reasonableness of this control method based on IEEE-37 distribution network.Results show that the phased-controlled coordinated charging method can minimize the load variance as well as the negative sequence current.
基金This work was supported by National Natural Science Foundation of China(51507168)International Science&Technology Cooperation Program of China(2016YFE0102200)Beijing information science and technology university 2017'training plan"project.
文摘Capacitive power transfer(CPT)technology is a newly emerging research focus for EV charging applications.Due to the absence of eddy current loss and light weight of the capacitive coupling metal plates,CPT technology is considered to be a promising alternative to the inductive power transfer(IPT)technology.In this paper,the recent designs of large-gap CPT systems designed for EV charging applications are summarized.And a graphical method based on Smith chart is proposed to analyze the characteristics of the compensation designs.With the design objectives graphically represented,the Smith chart can be used to visually analyze the performance of a compensation design,which could be helpful in multi-objectives design of the CPT system.The graphic features of three major design objectives on the Smith chart are investigated.Several guidelines of a good compensation design are concluded.
