To ensure running safety,the secondary spring loads of railway vehicles must be well equalized.Due to the coupling interactive effects of these hyper static suspended structures,the equalization adjustment through shi...To ensure running safety,the secondary spring loads of railway vehicles must be well equalized.Due to the coupling interactive effects of these hyper static suspended structures,the equalization adjustment through shimming procedure is quite complex.Therefore,an effective and reliable method in application is developed in this paper.Firstly,the best regulation of spring load is solved based on a mechanical model of the secondary suspension system,providing a target for actual adjustment.To reveal the relationship between secondary spring load distribution and shim quantity sequence,a forecasting model is constructed and then modified experimentally with consideration of car body’s elastic deformation.Further,a gradient-based algorithm with a momentum operation is proposed for the load optimization.Effectiveness of the whole method has been verified on a test rig.It is experimentally confirmed that this research provides an important basis for achieving an optimal regulation of spring load distribution for multiple types of railway vehicles.展开更多
Droop control has been widely used for controlling distributed generators.As capacity of the MMC inverter may be insufficient,a power allocation method for grid-connected MMC inverter based on droop control is present...Droop control has been widely used for controlling distributed generators.As capacity of the MMC inverter may be insufficient,a power allocation method for grid-connected MMC inverter based on droop control is presented to improve the stability of the power system.As there is potential for large disturbances in the power grid,an equal speed regulation strategy is adopted to make the speed of the voltage collapse be the same as the frequency collapse.With obtaining the active and reactive power references of MMC inverter according to equal speed regulation strategy,the deadbeat control method is calculated using these power references and adopted to track the reference currents.The Routh criterion is used to analyze the influence of the inductance measurement error on the control system.Additionally,a simulation model is established with Matlab and Simulink.The simulation results show that the stability of the power grid has been improved with the proposed control method.展开更多
基金Project(51305467)supported by the National Natural Science Foundation of ChinaProject(12JJ4050)supported by the Natural Science Foundation of Hunan Province,China
文摘To ensure running safety,the secondary spring loads of railway vehicles must be well equalized.Due to the coupling interactive effects of these hyper static suspended structures,the equalization adjustment through shimming procedure is quite complex.Therefore,an effective and reliable method in application is developed in this paper.Firstly,the best regulation of spring load is solved based on a mechanical model of the secondary suspension system,providing a target for actual adjustment.To reveal the relationship between secondary spring load distribution and shim quantity sequence,a forecasting model is constructed and then modified experimentally with consideration of car body’s elastic deformation.Further,a gradient-based algorithm with a momentum operation is proposed for the load optimization.Effectiveness of the whole method has been verified on a test rig.It is experimentally confirmed that this research provides an important basis for achieving an optimal regulation of spring load distribution for multiple types of railway vehicles.
基金by the National Key Research and Development Plan of China under Grant 2016YFB0901001。
文摘Droop control has been widely used for controlling distributed generators.As capacity of the MMC inverter may be insufficient,a power allocation method for grid-connected MMC inverter based on droop control is presented to improve the stability of the power system.As there is potential for large disturbances in the power grid,an equal speed regulation strategy is adopted to make the speed of the voltage collapse be the same as the frequency collapse.With obtaining the active and reactive power references of MMC inverter according to equal speed regulation strategy,the deadbeat control method is calculated using these power references and adopted to track the reference currents.The Routh criterion is used to analyze the influence of the inductance measurement error on the control system.Additionally,a simulation model is established with Matlab and Simulink.The simulation results show that the stability of the power grid has been improved with the proposed control method.
