The synchronous virtual machine uses inverter power to imitate the performance of the conventional synchronous machine.It also has the same inertia,damping,frequency,voltage regulation,and other external performance a...The synchronous virtual machine uses inverter power to imitate the performance of the conventional synchronous machine.It also has the same inertia,damping,frequency,voltage regulation,and other external performance as the generator.It is the key technology to realize new energy grid connections’stable and reliable operation.This project studies a dynamic simulation model of an extensive new energy power system based on the virtual synchronous motor.A new energy storage method is proposed.The mathematical energy storage model is established by combining the fixed rotor model of a synchronous virtual machine with the charge-discharge power,state of charge,operation efficiency,dead zone,and inverter constraint.The rapid conversion of energy storage devices absorbs the excess instantaneous kinetic energy caused by interference.The branch transient of the critical cut set in the system can be confined to a limited area.Thus,the virtual synchronizer’s kinetic and potential energy can be efficiently converted into an instantaneous state.The simulation of power system analysis software package(PSASP)verifies the correctness of the theory and algorithm in this paper.This paper provides a theoretical basis for improving the transient stability of new energy-connected power grids.展开更多
The 2009 M W 7.8 Fiordland (New Zealand) earthquake is the largest to have occurred in New Zealand since the 1931 M W 7.8 Hawke’s Bay earthquake, 1 000 km to the northwest. In this paper two tracks of ALOS PALSAR i...The 2009 M W 7.8 Fiordland (New Zealand) earthquake is the largest to have occurred in New Zealand since the 1931 M W 7.8 Hawke’s Bay earthquake, 1 000 km to the northwest. In this paper two tracks of ALOS PALSAR interferograms (one ascending and one descending) are used to determine fault geometry and slip distribution of this large earthquake. Modeling the event as dislocation in an elastic half-space suggests that the earthquake resulted from slip on a SSW-NNE orientated thrust fault that is associated with the subduction between the Pacific and Australian Plates, with oblique displacement of up to 6.3 m. This finding is consistent with the preliminary studies undertaken by the USGS using seismic data.展开更多
Hydrogen is an important source of energy. The natural resouces of hydrogen is plenty and it gives us lots of heat, and it is clean. One of difficulties of developing hydrogen sources of energy is hydrogen storage. Hy...Hydrogen is an important source of energy. The natural resouces of hydrogen is plenty and it gives us lots of heat, and it is clean. One of difficulties of developing hydrogen sources of energy is hydrogen storage. Hydrogen storage tank is either dangous or a little of capacity. Liquid hydrogen occupys small space. Liquefaction temprature of hydrogen is - 253℃and need better heat insulation protection, the volumn and weight of heat insulation layer are equal to hydrogen storage tank. Hydrogen storage utillizing hydrogen storage material is a very safety、 economical and effective method. Hydrogen storage material is either a medium of solid hydrogen storage or is negative pole active material of Ni-H battery,and is the one of key technoloy of fuel and Ni-H battery, it is an important material of new sources of energy too. Nanotechnology is introduced Mg-matrix hydrogen storage alloy and is achieved progress gteatly,but hydrogen storage alloy need be mede further improvment on applying investigation.展开更多
文摘The synchronous virtual machine uses inverter power to imitate the performance of the conventional synchronous machine.It also has the same inertia,damping,frequency,voltage regulation,and other external performance as the generator.It is the key technology to realize new energy grid connections’stable and reliable operation.This project studies a dynamic simulation model of an extensive new energy power system based on the virtual synchronous motor.A new energy storage method is proposed.The mathematical energy storage model is established by combining the fixed rotor model of a synchronous virtual machine with the charge-discharge power,state of charge,operation efficiency,dead zone,and inverter constraint.The rapid conversion of energy storage devices absorbs the excess instantaneous kinetic energy caused by interference.The branch transient of the critical cut set in the system can be confined to a limited area.Thus,the virtual synchronizer’s kinetic and potential energy can be efficiently converted into an instantaneous state.The simulation of power system analysis software package(PSASP)verifies the correctness of the theory and algorithm in this paper.This paper provides a theoretical basis for improving the transient stability of new energy-connected power grids.
基金supported jointly by the GAS project (Ref: NE/H001085/1)a China 863 Project (No.2009AA12Z317)+2 种基金supported by the Natural Environmental Research Council (NERC) through the National Center of Earth Observation (NCEO) of which the Center for the Observation and Modelling of Earthquakesfunded by a general project of National Natural Science Foundation of China (NS- FC) (No. 40902081)a key project of the Ministry of Land & Resources, China (No. 1212010914015)
文摘The 2009 M W 7.8 Fiordland (New Zealand) earthquake is the largest to have occurred in New Zealand since the 1931 M W 7.8 Hawke’s Bay earthquake, 1 000 km to the northwest. In this paper two tracks of ALOS PALSAR interferograms (one ascending and one descending) are used to determine fault geometry and slip distribution of this large earthquake. Modeling the event as dislocation in an elastic half-space suggests that the earthquake resulted from slip on a SSW-NNE orientated thrust fault that is associated with the subduction between the Pacific and Australian Plates, with oblique displacement of up to 6.3 m. This finding is consistent with the preliminary studies undertaken by the USGS using seismic data.
文摘Hydrogen is an important source of energy. The natural resouces of hydrogen is plenty and it gives us lots of heat, and it is clean. One of difficulties of developing hydrogen sources of energy is hydrogen storage. Hydrogen storage tank is either dangous or a little of capacity. Liquid hydrogen occupys small space. Liquefaction temprature of hydrogen is - 253℃and need better heat insulation protection, the volumn and weight of heat insulation layer are equal to hydrogen storage tank. Hydrogen storage utillizing hydrogen storage material is a very safety、 economical and effective method. Hydrogen storage material is either a medium of solid hydrogen storage or is negative pole active material of Ni-H battery,and is the one of key technoloy of fuel and Ni-H battery, it is an important material of new sources of energy too. Nanotechnology is introduced Mg-matrix hydrogen storage alloy and is achieved progress gteatly,but hydrogen storage alloy need be mede further improvment on applying investigation.