The interaction of U-shaped rings used for power transmission hardware with a wind-sand field is simulated numerically.A standard kturbulence model is used in synergy with an Eulerian-Lagrangian approach.The results...The interaction of U-shaped rings used for power transmission hardware with a wind-sand field is simulated numerically.A standard kturbulence model is used in synergy with an Eulerian-Lagrangian approach.The results show that the wind pressure on the windward side of the U-shaped ring is the highest,a negative pressure zone appears on both sides of the U-shaped ring,while a Kármán Vortex Street is created on its leeward side.There are three possible regimes of motion for the sand grains in the wind field.Sand grains with size below 0.125 mm can follow the airflow directly into the contact area of two U-shaped rings.When the sand size is about 0.1 mm,the number of sand grains that are blown into the contact area attains a maximum.Through the simulation of U-shaped rings in the wind-sand field,the dynamics of such processes are explained in detail,thereby providing relevant information for the subsequent protection and design of connecting hardware used for power transmission.展开更多
The distributed hierarchical control based on multi-agent system(MAS) is the main control method of micro-grids.By allowing more flexible interactions between computing components and their physical environments,cyber...The distributed hierarchical control based on multi-agent system(MAS) is the main control method of micro-grids.By allowing more flexible interactions between computing components and their physical environments,cyber physical system(CPS) presents a new approach for the distributed hierarchical engineering system,with micro-grids included.The object of this paper is to integrate the CPS concept with MAS technology and propose a new control framework for micro-grids.With the analysis of the operating mode and control method of micro-grids,the cyber physical control concepts of ontologybased semantic agent are discussed.Then an MAS-based architecture of cyber physical micro-grid system and an intelligent electronic device(IED) function structure are proposed.Finally,in order to operate and test the cyber physical micro-grid concept,an integrated simulation model is presented.展开更多
Based on the control requirements of artificial grass tufting machine,an overall plan is proposed on control of CANopen bus.In the control system,on the basis of CoDeSys soft PLC technology of fieldbus control system,...Based on the control requirements of artificial grass tufting machine,an overall plan is proposed on control of CANopen bus.In the control system,on the basis of CoDeSys soft PLC technology of fieldbus control system,LMC20 realizes the communication by making CANopen bus connect with ATV71,OTB module and these underlying slave stations.The humanized operation interface is realized by touch screens and user-friendly application which is developed through CoDeSys,and detailed analysis of the monitor system and the principle and method of monitor system are also provided in the paper.展开更多
基金National Natural Science Foundation of China(51865055)Tianshan Talents Plan of Xinjiang Autonomous Region of China(201720025)。
文摘The interaction of U-shaped rings used for power transmission hardware with a wind-sand field is simulated numerically.A standard kturbulence model is used in synergy with an Eulerian-Lagrangian approach.The results show that the wind pressure on the windward side of the U-shaped ring is the highest,a negative pressure zone appears on both sides of the U-shaped ring,while a Kármán Vortex Street is created on its leeward side.There are three possible regimes of motion for the sand grains in the wind field.Sand grains with size below 0.125 mm can follow the airflow directly into the contact area of two U-shaped rings.When the sand size is about 0.1 mm,the number of sand grains that are blown into the contact area attains a maximum.Through the simulation of U-shaped rings in the wind-sand field,the dynamics of such processes are explained in detail,thereby providing relevant information for the subsequent protection and design of connecting hardware used for power transmission.
基金National Natural Science Foundation of China(No.51477097)the State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources,China(No.LAPS13009)National High-Technology Research and Development Program of China(863 Program)(No.2013BAA01B04)
文摘The distributed hierarchical control based on multi-agent system(MAS) is the main control method of micro-grids.By allowing more flexible interactions between computing components and their physical environments,cyber physical system(CPS) presents a new approach for the distributed hierarchical engineering system,with micro-grids included.The object of this paper is to integrate the CPS concept with MAS technology and propose a new control framework for micro-grids.With the analysis of the operating mode and control method of micro-grids,the cyber physical control concepts of ontologybased semantic agent are discussed.Then an MAS-based architecture of cyber physical micro-grid system and an intelligent electronic device(IED) function structure are proposed.Finally,in order to operate and test the cyber physical micro-grid concept,an integrated simulation model is presented.
文摘Based on the control requirements of artificial grass tufting machine,an overall plan is proposed on control of CANopen bus.In the control system,on the basis of CoDeSys soft PLC technology of fieldbus control system,LMC20 realizes the communication by making CANopen bus connect with ATV71,OTB module and these underlying slave stations.The humanized operation interface is realized by touch screens and user-friendly application which is developed through CoDeSys,and detailed analysis of the monitor system and the principle and method of monitor system are also provided in the paper.
