Spiral springs have a wide range of applications in various fields.As a result of the complexity of friction,few theoretical analyses of spring belts under static loading have been carried out.Considering the piecewis...Spiral springs have a wide range of applications in various fields.As a result of the complexity of friction,few theoretical analyses of spring belts under static loading have been carried out.Considering the piecewise smooth property of the whole contact area,a simplified static model of spiral springs under loading is established in this paper.Besides,three main stress and friction distribution areas of the spring belt are proposed,namely,internal,transitional,and external regions.Since the outermost side of the spring is not subject to any pressure,a recursive method is adopted from the outside to the inside.The model provides the parameter conditions,i.e.,the internal and external forces are independent or dependent.Therefore,the case that the whole contact region of the spring belt has one subregion,two subregions,and three subregions is obtained.The model gives a theoretical basis for the parameter optimization of spiral springs.展开更多
Harvesting and storing energy is a key problem in some applications.Elastic energy storage technology has the advantages of wide-sources,simple structural principle,renewability,high effectiveness and environmental-fr...Harvesting and storing energy is a key problem in some applications.Elastic energy storage technology has the advantages of wide-sources,simple structural principle,renewability,high effectiveness and environmental-friendliness.This paper elaborates the operational principles and technical properties and summarizes the appli-cability of elastic energy storage technology with spiral springs.Elastic energy storage using spiral spring can realize the balance between energy supply and demand in some applications.Continuous input-spontaneous out-put working style can provide simple energy sources for short-time energy supply,and provide strong moment impact and rapid start,or realize the energy conservation for reciprocating movement.Uniform output working style can realize energy output with uniform speed for timekeeping and load-driving.Random input working style can harvest and store random mechanical energy or convert small torque into a large moment to drive external loads.Finally,this paper proposes new researches and developments of elastic energy storage technology on new materials and structures,mechanical properties and structural dynamics analyses,design and control for new functions.展开更多
For an innovative spiral spring energy storage system,the permanent magnet synchronous generator(PMSG)is utilized as the energy conversion device due to its simple structure,low weight and high torque.During power gen...For an innovative spiral spring energy storage system,the permanent magnet synchronous generator(PMSG)is utilized as the energy conversion device due to its simple structure,low weight and high torque.During power generation,the output torque and moment of inertia of the spiral spring are changing continuously and simultaneously and the parameters of the PMSG show uncertainties.Furthermore,the DC link voltage of the converter should be stable and the power injected into the grid needs to be controlled.First,the change features of the external power source and the uncertainties of the generator’s internal parameters are expressed as the comprehensive disturbances,which are introduced into the dynamic model of the PMSG and also modify the dynamic model.Then,the high gain observers are utilized to estimate the comprehensive disturbances,and an improved robust backstepping control scheme integrating L2 gain and high gain observers is proposed.Secondly,the gridside inverter controller for the DC voltage loop and reactive power loop is designed based on the backstepping theory.Finally,hardware implementation is fulfilled to verify the presented algorithm.The results show that high gain observers are able to accurately estimate the external and internal interferences;the proposed control scheme can effectively suppress the external and internal interferences and guarantees output current,operating speed of the PMSG and output reactive power to correctly track respective references,and effectively stabilize the DC link voltage.展开更多
As a driving element,the spiral torsion spring can control the release velocity by the optimization design of spring parameters and be used for separation devices,which is conducive to unlocking synchronicity and low-...As a driving element,the spiral torsion spring can control the release velocity by the optimization design of spring parameters and be used for separation devices,which is conducive to unlocking synchronicity and low-shock of the separation. On the basis of analyzing the performance requirements of the spiral torsion spring in a spacecraft device,the optimization design model of the spiral torsion spring is given, which takes the spiral torsion spring's length,width and thickness as the optimization variables,and the minimum volume as the optimization objective. The model considers output torque,strength,the maximal resetting load,holding force,and low shock as constraint conditions. A case is given to analyze the proposed model. The analysis results show the optimization scheme decreases the volume of the spiral torsion spring and meets the performance requirements of the separation device.展开更多
基金the National Natural Science Foundation of China(No.11972055)the National Defense Science and Technology Fund in the Technical Field of the Foundation Strengthening Plan(No.2020-JCJQ-JJ-009)the Civil Aerospace Pre-research Project(No.D020206)。
文摘Spiral springs have a wide range of applications in various fields.As a result of the complexity of friction,few theoretical analyses of spring belts under static loading have been carried out.Considering the piecewise smooth property of the whole contact area,a simplified static model of spiral springs under loading is established in this paper.Besides,three main stress and friction distribution areas of the spring belt are proposed,namely,internal,transitional,and external regions.Since the outermost side of the spring is not subject to any pressure,a recursive method is adopted from the outside to the inside.The model provides the parameter conditions,i.e.,the internal and external forces are independent or dependent.Therefore,the case that the whole contact region of the spring belt has one subregion,two subregions,and three subregions is obtained.The model gives a theoretical basis for the parameter optimization of spiral springs.
基金Thanks to Sichuan Province Innovation Team Project for Building Environment and Energy Efficient Utilization(No:2015TD0015)Major Project Engagement Fund of Southwest Jiaotong University,and Funda-mental Research Funds for the Central Universities(2682014CX014EM)for their financial aids.
文摘Harvesting and storing energy is a key problem in some applications.Elastic energy storage technology has the advantages of wide-sources,simple structural principle,renewability,high effectiveness and environmental-friendliness.This paper elaborates the operational principles and technical properties and summarizes the appli-cability of elastic energy storage technology with spiral springs.Elastic energy storage using spiral spring can realize the balance between energy supply and demand in some applications.Continuous input-spontaneous out-put working style can provide simple energy sources for short-time energy supply,and provide strong moment impact and rapid start,or realize the energy conservation for reciprocating movement.Uniform output working style can realize energy output with uniform speed for timekeeping and load-driving.Random input working style can harvest and store random mechanical energy or convert small torque into a large moment to drive external loads.Finally,this paper proposes new researches and developments of elastic energy storage technology on new materials and structures,mechanical properties and structural dynamics analyses,design and control for new functions.
基金This work was supported by the National Natural Science Foundation of China(No.51407077)the Fundamental Research Funds for the Central Universities of China(No.2014MS93)+1 种基金the Science and Technology Project of the State Grid Corporation of China Headquarters(No.5204BB16000F)and the Fundamental Research Funds for the State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(No.LAPS2016-28).
文摘For an innovative spiral spring energy storage system,the permanent magnet synchronous generator(PMSG)is utilized as the energy conversion device due to its simple structure,low weight and high torque.During power generation,the output torque and moment of inertia of the spiral spring are changing continuously and simultaneously and the parameters of the PMSG show uncertainties.Furthermore,the DC link voltage of the converter should be stable and the power injected into the grid needs to be controlled.First,the change features of the external power source and the uncertainties of the generator’s internal parameters are expressed as the comprehensive disturbances,which are introduced into the dynamic model of the PMSG and also modify the dynamic model.Then,the high gain observers are utilized to estimate the comprehensive disturbances,and an improved robust backstepping control scheme integrating L2 gain and high gain observers is proposed.Secondly,the gridside inverter controller for the DC voltage loop and reactive power loop is designed based on the backstepping theory.Finally,hardware implementation is fulfilled to verify the presented algorithm.The results show that high gain observers are able to accurately estimate the external and internal interferences;the proposed control scheme can effectively suppress the external and internal interferences and guarantees output current,operating speed of the PMSG and output reactive power to correctly track respective references,and effectively stabilize the DC link voltage.
基金Natural Science Foundation of Liaoning Province,China(No.2015020121)Research Fund for the Doctoral Program of Higher Education of China(No.20122125120013)the Fundamental Research Funds for the Central Universities,China(Nos.3132015087,3132014303)
文摘As a driving element,the spiral torsion spring can control the release velocity by the optimization design of spring parameters and be used for separation devices,which is conducive to unlocking synchronicity and low-shock of the separation. On the basis of analyzing the performance requirements of the spiral torsion spring in a spacecraft device,the optimization design model of the spiral torsion spring is given, which takes the spiral torsion spring's length,width and thickness as the optimization variables,and the minimum volume as the optimization objective. The model considers output torque,strength,the maximal resetting load,holding force,and low shock as constraint conditions. A case is given to analyze the proposed model. The analysis results show the optimization scheme decreases the volume of the spiral torsion spring and meets the performance requirements of the separation device.
