A novel fault ride-through strategy for wind turbines,based on permanent magnet synchronous generator,has been proposed.The proposed strategy analytically formulates the reference current signals,disregarding grid fau...A novel fault ride-through strategy for wind turbines,based on permanent magnet synchronous generator,has been proposed.The proposed strategy analytically formulates the reference current signals,disregarding grid fault type and utilizes the whole system capacity to inject the reactive current required by grid codes and deliver maximum possible active power to support grid frequency and avoid generation loss.All this has been reached by taking the grid-side converter’s phase current limit into account.The strategy is compatible with different countries’grid codes and prevents pulsating active power injection,in an unbalanced grid condition.Model predictive current controller is applied to handling rapid transients.During faults,the energy storage system maintains DC-link voltage,which causes voltage fluctuations to be eliminated,significantly.A fault ride-through strategy was proposed for PMSG-based wind turbines,neglecting fault characteristics,second,reaching maximum possible grid support in faulty grid conditions,while avoiding over-current and third,considerable reduction in energy storage system size and power rating.Inspiring simulations have been carried out through MATLAB/SIMULINK to validate the feasibility and competency of the proposed fault ride-through method and efficiency of the entire control system.展开更多
A set of water powered excavation test system was developed for the comprehensive performance testing and evaluation of water powered percussive rock drill indoors. The whole system contains hydraulic power section, e...A set of water powered excavation test system was developed for the comprehensive performance testing and evaluation of water powered percussive rock drill indoors. The whole system contains hydraulic power section, electronic control system, test and data acquisition system, and assistant devices, such as guideway and drilling bench. Parameters of the water powered percussive rock drill can be obtained by analyzing testing data, which contain impact energy, front and back cavity pressure, pressure and flow in each working part, drilling velocity, frequency and energy efficiency etc. The system is applied to test the self-designed water powered percussive rock drill SYYG65. The parameters of water powered percussive rock drill with impact pressure of about 8.9 MPa are 58.93 J for impact energy, and 8.97% for energy efficiency, which prove the effectiveness of system.展开更多
文摘A novel fault ride-through strategy for wind turbines,based on permanent magnet synchronous generator,has been proposed.The proposed strategy analytically formulates the reference current signals,disregarding grid fault type and utilizes the whole system capacity to inject the reactive current required by grid codes and deliver maximum possible active power to support grid frequency and avoid generation loss.All this has been reached by taking the grid-side converter’s phase current limit into account.The strategy is compatible with different countries’grid codes and prevents pulsating active power injection,in an unbalanced grid condition.Model predictive current controller is applied to handling rapid transients.During faults,the energy storage system maintains DC-link voltage,which causes voltage fluctuations to be eliminated,significantly.A fault ride-through strategy was proposed for PMSG-based wind turbines,neglecting fault characteristics,second,reaching maximum possible grid support in faulty grid conditions,while avoiding over-current and third,considerable reduction in energy storage system size and power rating.Inspiring simulations have been carried out through MATLAB/SIMULINK to validate the feasibility and competency of the proposed fault ride-through method and efficiency of the entire control system.
基金Project(2006AA06Z134) supported by the National High Technology Research and Development Program of ChinaProjects(50934006, 50904079) supported by the National Natural Science Foundation of China
文摘A set of water powered excavation test system was developed for the comprehensive performance testing and evaluation of water powered percussive rock drill indoors. The whole system contains hydraulic power section, electronic control system, test and data acquisition system, and assistant devices, such as guideway and drilling bench. Parameters of the water powered percussive rock drill can be obtained by analyzing testing data, which contain impact energy, front and back cavity pressure, pressure and flow in each working part, drilling velocity, frequency and energy efficiency etc. The system is applied to test the self-designed water powered percussive rock drill SYYG65. The parameters of water powered percussive rock drill with impact pressure of about 8.9 MPa are 58.93 J for impact energy, and 8.97% for energy efficiency, which prove the effectiveness of system.
