With the increasing of electric vehicles(EVs)penetration in power grids,the charging of EVs will have significant impacts on power system planning and operation.It is necessary to note that the majority of EVs are not...With the increasing of electric vehicles(EVs)penetration in power grids,the charging of EVs will have significant impacts on power system planning and operation.It is necessary to note that the majority of EVs are not in use in most ofthe time in a day.Therefore,the onboard batteries can be utilized as energy storage devices.This article reviews and discusses the current related research in the following areas.展开更多
Global effects caused by the detonation of an IED near a military vehicle induce subsequent severe acceleration effects on the vehicle occupants.Two concepts to minimize these global effects were developed,with the he...Global effects caused by the detonation of an IED near a military vehicle induce subsequent severe acceleration effects on the vehicle occupants.Two concepts to minimize these global effects were developed,with the help of a combined method based on a scaled experimental technology and numerical simulations.The first concept consists in the optimization of the vehicle shape to reduce the momentum transfer and thus the occupant loading.Three scaled V-shaped vehicles with different ground clearances were built and compared to a reference vehicle equipped with a flat floor.The second concept,called dynamic impulse compensation(DIC),is based on a momentum compensation technique.The principal possibility of this concept was demonstrated on a scaled vehicle.In addition,the numerical simulations have been performed with generic full size vehicles including dummy models,proving the capability of the DIC technology to reduce the occupant loading.展开更多
The joint resource block(RB)allocation and power optimization problem is studied to maximize the sum-rate of the vehicle-to-vehicle(V2V)links in the device-to-device(D2D)-enabled V2V communication system,where one fea...The joint resource block(RB)allocation and power optimization problem is studied to maximize the sum-rate of the vehicle-to-vehicle(V2V)links in the device-to-device(D2D)-enabled V2V communication system,where one feasible cellular user(FCU)can share its RB with multiple V2V pairs.The problem is first formulated as a nonconvex mixed-integer nonlinear programming(MINLP)problem with constraint of the maximum interference power in the FCU links.Using the game theory,two coalition formation algorithms are proposed to accomplish V2V link partitioning and FCU selection,where the transferable utility functions are introduced to minimize the interference among the V2V links and the FCU links for the optimal RB allocation.The successive convex approximation(SCA)is used to transform the original problem into a convex one and the Lagrangian dual method is further applied to obtain the optimal transmit power of the V2V links.Finally,numerical results demonstrate the efficiency of the proposed resource allocation algorithm in terms of the system sum-rate.展开更多
It is essential to maximize capacity while satisfying the transmission time delay of unmanned aerial vehicle(UAV)swarm communication system.In order to address this challenge,a dynamic decentralized optimization mecha...It is essential to maximize capacity while satisfying the transmission time delay of unmanned aerial vehicle(UAV)swarm communication system.In order to address this challenge,a dynamic decentralized optimization mechanism is presented for the realization of joint spectrum and power(JSAP)resource allocation based on deep Q-learning networks(DQNs).Each UAV to UAV(U2U)link is regarded as an agent that is capable of identifying the optimal spectrum and power to communicate with one another.The convolutional neural network,target network,and experience replay are adopted while training.The findings of the simulation indicate that the proposed method has the potential to improve both communication capacity and probability of successful data transmission when compared with random centralized assignment and multichannel access methods.展开更多
双向功率变换器是实现电动汽车V2G(Vehicle to grid)技术的关键性设备。引入集成技术,利用共享车载驱动电机和驱动电力电子变换装置,提出一种新的集成式双向车载功率变换器。它既可以将电动汽车蓄电池能量回馈给电网,又可完成蓄电池充...双向功率变换器是实现电动汽车V2G(Vehicle to grid)技术的关键性设备。引入集成技术,利用共享车载驱动电机和驱动电力电子变换装置,提出一种新的集成式双向车载功率变换器。它既可以将电动汽车蓄电池能量回馈给电网,又可完成蓄电池充电功能。集成式功率变换器具有单相、三相充/放电接口,实现了一机多口,增强了车载系统的紧凑性。分析不同充/放电模式下的集成功率变换器拓扑,给出了充/放电模式下的控制策略。最后,给出了仿真和试验结果,验证了多端口集成车载功率变换器的可行性。展开更多
Large-scale electric vehicles(EVs) connected to the micro grid would cause many problems. In this paper, with the consideration of vehicle to grid(V2 G), two charging and discharging load modes of EVs were constructed...Large-scale electric vehicles(EVs) connected to the micro grid would cause many problems. In this paper, with the consideration of vehicle to grid(V2 G), two charging and discharging load modes of EVs were constructed. One was the disorderly charging and discharging mode based on travel habits, and the other was the orderly charging and discharging mode based on time-of-use(TOU) price;Monte Carlo method was used to verify the case. The scheme of the capacity optimization of photovoltaic charging station under two different charging and discharging modes with V2 G was proposed. The mathematical models of the objective function with the maximization of energy efficiency, the minimization of the investment and the operation cost of the charging system were established. The range of decision variables, constraints of the requirements of the power balance and the strategy of energy exchange were given. NSGA-Ⅱ and NSGA-SA algorithm were used to verify the cases, respectively. In both algorithms, by comparing with the simulation results of the two different modes, it shows that the orderly charging and discharging mode with V2 G is obviously better than the disorderly charging and discharging mode in the aspects of alleviating the pressure of power grid, reducing system investment and improving energy efficiency.展开更多
为了降低车联网(Long Term Evolution-Vehicle to Everything,LTE-V)终端间的相互干扰并提升通信的可靠性,提出通过资源分配和拥塞控制来解决资源碰撞的问题。依据信道忙率(Channel Busy Ratio,CBR)划分拥塞等级,融合资源分配与拥塞控...为了降低车联网(Long Term Evolution-Vehicle to Everything,LTE-V)终端间的相互干扰并提升通信的可靠性,提出通过资源分配和拥塞控制来解决资源碰撞的问题。依据信道忙率(Channel Busy Ratio,CBR)划分拥塞等级,融合资源分配与拥塞控制提出相应的方案,形成资源碰撞避免机制。为了减少重选资源时发生的碰撞,提出了资源重选竞争退避机制以降低重选带来的不确定性;针对拥塞导致的碰撞,改变调制编码策略从而优化资源占用。仿真结果表明,与标准中基于感知的半持续调度(Semi-persistent Scheduling,SPS)相比,所提出的机制在传输距离为300 m时可以实现0.85以上的数据包投递率,有效减少资源碰撞,提升传输可靠性。展开更多
文摘With the increasing of electric vehicles(EVs)penetration in power grids,the charging of EVs will have significant impacts on power system planning and operation.It is necessary to note that the majority of EVs are not in use in most ofthe time in a day.Therefore,the onboard batteries can be utilized as energy storage devices.This article reviews and discusses the current related research in the following areas.
基金Herr TRDir K.Husing from the German test range WTD-91 GF-440 in MeppenHerr TRDir K.Neugebauer from BAAINBw
文摘Global effects caused by the detonation of an IED near a military vehicle induce subsequent severe acceleration effects on the vehicle occupants.Two concepts to minimize these global effects were developed,with the help of a combined method based on a scaled experimental technology and numerical simulations.The first concept consists in the optimization of the vehicle shape to reduce the momentum transfer and thus the occupant loading.Three scaled V-shaped vehicles with different ground clearances were built and compared to a reference vehicle equipped with a flat floor.The second concept,called dynamic impulse compensation(DIC),is based on a momentum compensation technique.The principal possibility of this concept was demonstrated on a scaled vehicle.In addition,the numerical simulations have been performed with generic full size vehicles including dummy models,proving the capability of the DIC technology to reduce the occupant loading.
基金the National Natural Scientific Foundation of China(61771291,61571272)the Major Science and Technological Innovation Project of Shandong Province(2020CXGC010109).
文摘The joint resource block(RB)allocation and power optimization problem is studied to maximize the sum-rate of the vehicle-to-vehicle(V2V)links in the device-to-device(D2D)-enabled V2V communication system,where one feasible cellular user(FCU)can share its RB with multiple V2V pairs.The problem is first formulated as a nonconvex mixed-integer nonlinear programming(MINLP)problem with constraint of the maximum interference power in the FCU links.Using the game theory,two coalition formation algorithms are proposed to accomplish V2V link partitioning and FCU selection,where the transferable utility functions are introduced to minimize the interference among the V2V links and the FCU links for the optimal RB allocation.The successive convex approximation(SCA)is used to transform the original problem into a convex one and the Lagrangian dual method is further applied to obtain the optimal transmit power of the V2V links.Finally,numerical results demonstrate the efficiency of the proposed resource allocation algorithm in terms of the system sum-rate.
基金supported by the National Natural Science Foundation of China(62031017,61971221).
文摘It is essential to maximize capacity while satisfying the transmission time delay of unmanned aerial vehicle(UAV)swarm communication system.In order to address this challenge,a dynamic decentralized optimization mechanism is presented for the realization of joint spectrum and power(JSAP)resource allocation based on deep Q-learning networks(DQNs).Each UAV to UAV(U2U)link is regarded as an agent that is capable of identifying the optimal spectrum and power to communicate with one another.The convolutional neural network,target network,and experience replay are adopted while training.The findings of the simulation indicate that the proposed method has the potential to improve both communication capacity and probability of successful data transmission when compared with random centralized assignment and multichannel access methods.
文摘双向功率变换器是实现电动汽车V2G(Vehicle to grid)技术的关键性设备。引入集成技术,利用共享车载驱动电机和驱动电力电子变换装置,提出一种新的集成式双向车载功率变换器。它既可以将电动汽车蓄电池能量回馈给电网,又可完成蓄电池充电功能。集成式功率变换器具有单相、三相充/放电接口,实现了一机多口,增强了车载系统的紧凑性。分析不同充/放电模式下的集成功率变换器拓扑,给出了充/放电模式下的控制策略。最后,给出了仿真和试验结果,验证了多端口集成车载功率变换器的可行性。
基金Project(3502Z20179026)supported by Xiamen Science and Technology Project,China。
文摘Large-scale electric vehicles(EVs) connected to the micro grid would cause many problems. In this paper, with the consideration of vehicle to grid(V2 G), two charging and discharging load modes of EVs were constructed. One was the disorderly charging and discharging mode based on travel habits, and the other was the orderly charging and discharging mode based on time-of-use(TOU) price;Monte Carlo method was used to verify the case. The scheme of the capacity optimization of photovoltaic charging station under two different charging and discharging modes with V2 G was proposed. The mathematical models of the objective function with the maximization of energy efficiency, the minimization of the investment and the operation cost of the charging system were established. The range of decision variables, constraints of the requirements of the power balance and the strategy of energy exchange were given. NSGA-Ⅱ and NSGA-SA algorithm were used to verify the cases, respectively. In both algorithms, by comparing with the simulation results of the two different modes, it shows that the orderly charging and discharging mode with V2 G is obviously better than the disorderly charging and discharging mode in the aspects of alleviating the pressure of power grid, reducing system investment and improving energy efficiency.
文摘为了降低车联网(Long Term Evolution-Vehicle to Everything,LTE-V)终端间的相互干扰并提升通信的可靠性,提出通过资源分配和拥塞控制来解决资源碰撞的问题。依据信道忙率(Channel Busy Ratio,CBR)划分拥塞等级,融合资源分配与拥塞控制提出相应的方案,形成资源碰撞避免机制。为了减少重选资源时发生的碰撞,提出了资源重选竞争退避机制以降低重选带来的不确定性;针对拥塞导致的碰撞,改变调制编码策略从而优化资源占用。仿真结果表明,与标准中基于感知的半持续调度(Semi-persistent Scheduling,SPS)相比,所提出的机制在传输距离为300 m时可以实现0.85以上的数据包投递率,有效减少资源碰撞,提升传输可靠性。
