For the battery only power system is hard to meet the energy and power requirements reasonably, a hybrid power system with uhracapacitor and battery is studied. A Topology structure is analyzed that the uhracapacitor ...For the battery only power system is hard to meet the energy and power requirements reasonably, a hybrid power system with uhracapacitor and battery is studied. A Topology structure is analyzed that the uhracapacitor system is connected with battery pack parallel after a bidirectional DC/DC converter. The ultracapacitor, battery and the hybrid power system are modeled. For the plug-in hybrid electric vehicle (PHEV) application, the control target and control strategy of the hybrid power system are put forward. From the simulation results based on the Chinese urban driving cycle, the hybrid power system could meet the peak power requirements reasonably while the battery pack' s current is controlled in a reasonable limit which will be helpful to optimize the battery pack' s working conditions to get long cycling life and high efficiency.展开更多
Electrifying the transport sector requires new possibilities for power electronics converters to attain reliable and efficient charging solutions for electric vehicles(EVs).With the continuous development in power ele...Electrifying the transport sector requires new possibilities for power electronics converters to attain reliable and efficient charging solutions for electric vehicles(EVs).With the continuous development in power electronics converters,the desire to reduce gasoline consumption and to increase the battery capacity for more electric range is achievable for EVs in the near future.The main interface between the power network and EV battery system is a power electronics converter,therefore,there is a considerable need of new power converters with low cost and high reliability for the advance charging mechanism of EVs.The rapid growth in power converter topologies brings substantial opportunities in EV charging process.In view of this fact,this paper investigates the significant aspects,current progress,and challenges associated with several power converters to suggest further improvements in charging systems of EVs.In particular,an extensive analysis of front-end as well as back-end converter configurations is presented.Moreover,the comparative properties of resonant converter topologies along with other DCDC converters are discussed in detail.Additionally,isolated,and non-isolated topologies with soft switching techniques are classified and rigorously analyzed with a view to their respective issues and benefits.It is foreseen that this paper would be a valuable addition and a worthy source of information for researchers exploring the area of power converter topologies for charging solutions of EVs.展开更多
Network devices are equipped with low power states but they are rarely activated due to their inability of maintaining network connectivity. Recently, Network Connectivity Proxy (NCP) concept has been proposed in li...Network devices are equipped with low power states but they are rarely activated due to their inability of maintaining network connectivity. Recently, Network Connectivity Proxy (NCP) concept has been proposed in literature as an effective mechanism to exploit full potential of low power features on network devices by impersonating their virtual presence. However, the NCP concept faces several open issues and challenges especially related to proxying of TCP connections and majority of daily used proprietary dosed-source applications. This paper presents a new approach for reducing network energy waste through intelligent collaboration among daily used devices (e.g., desktop computers, laptops, tablets, smartphones, etc). It guarantees to run applications on only and only one user device that is under active use at that specific moment. To reduce energy waste and allow idle devices to sleep, our approach also takes benefit from a light- weight home gateway proxy with very basic practically realizable functionalities. The proposed system not just reduces energy waste of fixed devices but also enables mobile devices to significantly improve their battery life. Our developed software prototypes allow devices to autonomously and seamlessly collaborate with each other without requiring any configuration or user input. Further, this paper also presents the basic performance evaluation of developed prototypes in real networking environments.展开更多
文摘For the battery only power system is hard to meet the energy and power requirements reasonably, a hybrid power system with uhracapacitor and battery is studied. A Topology structure is analyzed that the uhracapacitor system is connected with battery pack parallel after a bidirectional DC/DC converter. The ultracapacitor, battery and the hybrid power system are modeled. For the plug-in hybrid electric vehicle (PHEV) application, the control target and control strategy of the hybrid power system are put forward. From the simulation results based on the Chinese urban driving cycle, the hybrid power system could meet the peak power requirements reasonably while the battery pack' s current is controlled in a reasonable limit which will be helpful to optimize the battery pack' s working conditions to get long cycling life and high efficiency.
文摘Electrifying the transport sector requires new possibilities for power electronics converters to attain reliable and efficient charging solutions for electric vehicles(EVs).With the continuous development in power electronics converters,the desire to reduce gasoline consumption and to increase the battery capacity for more electric range is achievable for EVs in the near future.The main interface between the power network and EV battery system is a power electronics converter,therefore,there is a considerable need of new power converters with low cost and high reliability for the advance charging mechanism of EVs.The rapid growth in power converter topologies brings substantial opportunities in EV charging process.In view of this fact,this paper investigates the significant aspects,current progress,and challenges associated with several power converters to suggest further improvements in charging systems of EVs.In particular,an extensive analysis of front-end as well as back-end converter configurations is presented.Moreover,the comparative properties of resonant converter topologies along with other DCDC converters are discussed in detail.Additionally,isolated,and non-isolated topologies with soft switching techniques are classified and rigorously analyzed with a view to their respective issues and benefits.It is foreseen that this paper would be a valuable addition and a worthy source of information for researchers exploring the area of power converter topologies for charging solutions of EVs.
文摘Network devices are equipped with low power states but they are rarely activated due to their inability of maintaining network connectivity. Recently, Network Connectivity Proxy (NCP) concept has been proposed in literature as an effective mechanism to exploit full potential of low power features on network devices by impersonating their virtual presence. However, the NCP concept faces several open issues and challenges especially related to proxying of TCP connections and majority of daily used proprietary dosed-source applications. This paper presents a new approach for reducing network energy waste through intelligent collaboration among daily used devices (e.g., desktop computers, laptops, tablets, smartphones, etc). It guarantees to run applications on only and only one user device that is under active use at that specific moment. To reduce energy waste and allow idle devices to sleep, our approach also takes benefit from a light- weight home gateway proxy with very basic practically realizable functionalities. The proposed system not just reduces energy waste of fixed devices but also enables mobile devices to significantly improve their battery life. Our developed software prototypes allow devices to autonomously and seamlessly collaborate with each other without requiring any configuration or user input. Further, this paper also presents the basic performance evaluation of developed prototypes in real networking environments.