Multi-modular system plays an important role in power system architecture because low voltage and low power converters can be connected in any combination parallel or series at input/ output side in order to obtained ...Multi-modular system plays an important role in power system architecture because low voltage and low power converters can be connected in any combination parallel or series at input/ output side in order to obtained any given power system specifications. Multi-modular boost haft bridge DC-DC converter in the configuration of input series output parallel has been investigated in this paper. The boost half bridge DC-DC converters are connected in input series output parallel con- figuration in order to achieve equal input voltage sharing and output current sharing between the con- verters. This can be achieved with the help of dynamic control scheme which consists of two loops, a voltage loop and a current loop, for each module. Dynamic behavior of multi-modular converter configuration has been observe by varying the load condition. Moreover, the results obtained through multi-modular converter describe that the system has good dynamic and steady state response. Al- though two converter modules are focused in this paper but it can be modified to any number of modules.展开更多
The rapid expansion of enterprises makes product collaborative design （PCD） a critical issue under the distributed heterogeneous environment, but as the collaborative task of large-scale network becomes more complic...The rapid expansion of enterprises makes product collaborative design （PCD） a critical issue under the distributed heterogeneous environment, but as the collaborative task of large-scale network becomes more complicated, neither unified task decomposition and allocation methodology nor Agent-based network management platform can satisfy the increasing demands. In this paper, to meet requirements of PCD for distributed product development, a collaborative design mechanism based on the thought of modularity and the Agent technology is presented. First, the top-down 4-tier process model based on task-oriented modular and Agent is constructed for PCD after analyzing the mapping relationships between requirements and functions in the collaborative design. Second, on basis of sub-task decomposition for PCD based on a mixed method, the mathematic model of task-oriented modular based on multi-objective optimization is established to maximize the module cohesion degree and minimize the module coupling degree, while considering the module executable degree as a restriction. The mathematic model is optimized and simulated by the modified PSO, and the decomposed modules are obtained. Finally, the Agent structure model for collaborative design is put forward, and the optimism matching Agents are selected by using similarity algorithm to implement different task-modules by the integrated reasoning and decision-making mechanism with the behavioral model of collaborative design Agents. With the results of experimental studies for automobile collaborative design, the feasibility and efficiency of this methodology of task-oriented modular and Agent-based collaborative design in the distributed heterogeneous environment are verified. On this basis, an integrative automobile collaborative R＆D platform is developed. This research provides an effective platform for automobile manufacturing enterprises to achieve PCD, and helps to promote product numeralization collaborative R＆D and management development.展开更多
This paper presents a new topology to connect high voltage direct current(HVDC) offshore wind farm into the grid.The offshore part consists of five units,each unit contains permanent magnet synchronous generator(PMSG)...This paper presents a new topology to connect high voltage direct current(HVDC) offshore wind farm into the grid.The offshore part consists of five units,each unit contains permanent magnet synchronous generator(PMSG) connected to three-phase/three-phase matrix converter to control the generator speed by using a maximum power point tracking(MPPT) control.The offshore platform consists of a three-phase medium frequency transformer(MFT) and a modular multi-level converter(MMC).The primary of each phase of the transformer connected to one phase from each unit.The secondary of the transformer connected to MMC to get HVDC.The HVDC cable will be used to transfer power from the offshore side to the on-shore side.Five-level MMC is used in the onshore side to control the DC voltage and to connect the offshore wind farm into the grid by converting the HVDC to high voltage alternative current(HVAC).展开更多
A Cascade H Bridge (CHB) is evaluated for both electric vehicle motor traction control and off-vehicle charging against the Power ElectronicsUK Automotive Challenge for cost and mass for the year 2035. By combining th...A Cascade H Bridge (CHB) is evaluated for both electric vehicle motor traction control and off-vehicle charging against the Power ElectronicsUK Automotive Challenge for cost and mass for the year 2035. By combining the power electronics with batteries using low-voltage MOSFET transistors in a series cascade arrangement the cost and mass targets could be met 12 years earlier (in 2023 and 20 times lighter if an application specific integrated circuit (ASIC) is used. A 200 kW peak reference car was used to evaluate cost and mass benefits using four different topologies of power electronics. Vehicle installation is shown to be simplified as only passive cooling is required removing the need for liquid cooling systems and the arrangement is inherently safe;no high voltages are present when the vehicle is stationary. The inherently higher efficiency of CHB increases vehicle range. The converter with integrated batteries can also behave as an integrated on-board battery charger delivering additional off-vehicle benefits by removing the need for costly external chargers.展开更多
Considering research on multi-objective optimization for reliability and performance suffering cost constraints in digital circuits,an improved multi-objective optimization algorithm based on performance and reliabili...Considering research on multi-objective optimization for reliability and performance suffering cost constraints in digital circuits,an improved multi-objective optimization algorithm based on performance and reliability was proposed to solve the problem of discrete system resources configuration in this paper. This algorithm used the particle-swarm optimization( PSO) to evaluate the tradeoffs configuration of the system resources between reliability and performance and proved the feasibility through the simulation.Finally, the information of resources configuration from optimization algorithm was used to effectively guide the system design so as to mitigate soft errors caused by single event effect( SEE).展开更多
为解决复杂工况下分布式驱动电车(Distributed Drive Electric Vehicle,DDEV)的驱动防滑问题,基于模块化提出了一种多智能体分布式协同控制策略。首先,采用模块化的方法搭建了整车结构,将各轮毂电机车轮和控制器整体视为一个智能体,根...为解决复杂工况下分布式驱动电车(Distributed Drive Electric Vehicle,DDEV)的驱动防滑问题,基于模块化提出了一种多智能体分布式协同控制策略。首先,采用模块化的方法搭建了整车结构,将各轮毂电机车轮和控制器整体视为一个智能体,根据车轮运动学和整车运动学建立智能体的滑转率模型;然后,设计了基于多智能体的分布式模型预测控制策略,以多约束条件下的协同优化为目标函数,实现驱动防滑,在解决驱动力不足问题的同时,达到了低能耗和舒适性;最后,利用Simulink软件和CarSim软件进行仿真实验,实验结果证明了所提控制策略的有效性,为分布式驱动的进一步应用提供了新的控制方法。展开更多
文摘Multi-modular system plays an important role in power system architecture because low voltage and low power converters can be connected in any combination parallel or series at input/ output side in order to obtained any given power system specifications. Multi-modular boost haft bridge DC-DC converter in the configuration of input series output parallel has been investigated in this paper. The boost half bridge DC-DC converters are connected in input series output parallel con- figuration in order to achieve equal input voltage sharing and output current sharing between the con- verters. This can be achieved with the help of dynamic control scheme which consists of two loops, a voltage loop and a current loop, for each module. Dynamic behavior of multi-modular converter configuration has been observe by varying the load condition. Moreover, the results obtained through multi-modular converter describe that the system has good dynamic and steady state response. Al- though two converter modules are focused in this paper but it can be modified to any number of modules.
基金Supported by National Science and Technology Major Project of China(Grant No.2009ZX04014-103)PhD Programs Foundation of Ministry of Education of China(Grant No.20100072110038)+1 种基金National Natural Science Foundation of China(Grant Nos.61075064,61034004,61005090)Program for New Century Excellent Talents in University of Ministry of Education of China(Grant No.NECT-10-0633)
文摘The rapid expansion of enterprises makes product collaborative design （PCD） a critical issue under the distributed heterogeneous environment, but as the collaborative task of large-scale network becomes more complicated, neither unified task decomposition and allocation methodology nor Agent-based network management platform can satisfy the increasing demands. In this paper, to meet requirements of PCD for distributed product development, a collaborative design mechanism based on the thought of modularity and the Agent technology is presented. First, the top-down 4-tier process model based on task-oriented modular and Agent is constructed for PCD after analyzing the mapping relationships between requirements and functions in the collaborative design. Second, on basis of sub-task decomposition for PCD based on a mixed method, the mathematic model of task-oriented modular based on multi-objective optimization is established to maximize the module cohesion degree and minimize the module coupling degree, while considering the module executable degree as a restriction. The mathematic model is optimized and simulated by the modified PSO, and the decomposed modules are obtained. Finally, the Agent structure model for collaborative design is put forward, and the optimism matching Agents are selected by using similarity algorithm to implement different task-modules by the integrated reasoning and decision-making mechanism with the behavioral model of collaborative design Agents. With the results of experimental studies for automobile collaborative design, the feasibility and efficiency of this methodology of task-oriented modular and Agent-based collaborative design in the distributed heterogeneous environment are verified. On this basis, an integrative automobile collaborative R＆D platform is developed. This research provides an effective platform for automobile manufacturing enterprises to achieve PCD, and helps to promote product numeralization collaborative R＆D and management development.
文摘This paper presents a new topology to connect high voltage direct current(HVDC) offshore wind farm into the grid.The offshore part consists of five units,each unit contains permanent magnet synchronous generator(PMSG) connected to three-phase/three-phase matrix converter to control the generator speed by using a maximum power point tracking(MPPT) control.The offshore platform consists of a three-phase medium frequency transformer(MFT) and a modular multi-level converter(MMC).The primary of each phase of the transformer connected to one phase from each unit.The secondary of the transformer connected to MMC to get HVDC.The HVDC cable will be used to transfer power from the offshore side to the on-shore side.Five-level MMC is used in the onshore side to control the DC voltage and to connect the offshore wind farm into the grid by converting the HVDC to high voltage alternative current(HVAC).
文摘A Cascade H Bridge (CHB) is evaluated for both electric vehicle motor traction control and off-vehicle charging against the Power ElectronicsUK Automotive Challenge for cost and mass for the year 2035. By combining the power electronics with batteries using low-voltage MOSFET transistors in a series cascade arrangement the cost and mass targets could be met 12 years earlier (in 2023 and 20 times lighter if an application specific integrated circuit (ASIC) is used. A 200 kW peak reference car was used to evaluate cost and mass benefits using four different topologies of power electronics. Vehicle installation is shown to be simplified as only passive cooling is required removing the need for liquid cooling systems and the arrangement is inherently safe;no high voltages are present when the vehicle is stationary. The inherently higher efficiency of CHB increases vehicle range. The converter with integrated batteries can also behave as an integrated on-board battery charger delivering additional off-vehicle benefits by removing the need for costly external chargers.
文摘Considering research on multi-objective optimization for reliability and performance suffering cost constraints in digital circuits,an improved multi-objective optimization algorithm based on performance and reliability was proposed to solve the problem of discrete system resources configuration in this paper. This algorithm used the particle-swarm optimization( PSO) to evaluate the tradeoffs configuration of the system resources between reliability and performance and proved the feasibility through the simulation.Finally, the information of resources configuration from optimization algorithm was used to effectively guide the system design so as to mitigate soft errors caused by single event effect( SEE).
文摘为解决复杂工况下分布式驱动电车(Distributed Drive Electric Vehicle,DDEV)的驱动防滑问题,基于模块化提出了一种多智能体分布式协同控制策略。首先,采用模块化的方法搭建了整车结构,将各轮毂电机车轮和控制器整体视为一个智能体,根据车轮运动学和整车运动学建立智能体的滑转率模型;然后,设计了基于多智能体的分布式模型预测控制策略,以多约束条件下的协同优化为目标函数,实现驱动防滑,在解决驱动力不足问题的同时,达到了低能耗和舒适性;最后,利用Simulink软件和CarSim软件进行仿真实验,实验结果证明了所提控制策略的有效性,为分布式驱动的进一步应用提供了新的控制方法。
