The high-speed on/off valve(HSV)serves as the fundamental component responsible for generating discrete fluids within digital hydraulic systems.As the switching frequency of the HSV increases,the properties of the gen...The high-speed on/off valve(HSV)serves as the fundamental component responsible for generating discrete fluids within digital hydraulic systems.As the switching frequency of the HSV increases,the properties of the generated discrete fluid approach those of continuous fluids.Therefore,a higher frequency response characteristic of HSV is the key to ensure the control accuracy of digital hydraulic systems.However,the current research mainly focuses on its dynamic performance,but neglect its FRC.This paper presents a theoretical analysis demonstrating that the FRC of the HSV can be enhanced by minimizing its switching time.The maximum switching frequency(MSF)is mainly determined by opening dynamic performance when HSV operates with low switching duty ratio(SDR),whereas the closing dynamic performance limits the MSF when HSV operates with high SDR.Building upon these findings,the pre-excitation control algorithm(PECA)is proposed to reduce the switching time of the HSV,and consequently enhance its FRC.Experimental results demonstrate that PECA shortens the opening delay time of HSV by 1.12 ms,the closing delay time by 2.54 ms,and the closing moving time by 0.47 ms in comparison to the existing advanced control algorithms.As a result,a larger MSF of 417 Hz and a wider controllable SDR range from 20%to 70%were achieved at a switching frequency of 250 Hz.Thus,the proposed PFCA in this paper has been verified as an effective and promising approach for enhancing the control performance of digital hydraulic systems.展开更多
To improve energy density,the transportation,storage,and operations of hydrogen,methane,and compressed air vehicles currently require high-pressure compression.High-pressure solenoid valve becomes the vital element to...To improve energy density,the transportation,storage,and operations of hydrogen,methane,and compressed air vehicles currently require high-pressure compression.High-pressure solenoid valve becomes the vital element to above system.In order to reduce leakage and aerodynamic force influence,a new type high-pressure solenoid valve was proposed.The simulation model which included electromagnetic model,aerodynamic force model was established by means of the nonlinear mathematic models.Using the software MATLAB/Simulink for simulation,the dynamic response characteristics of high-pressure pneumatic solenoid valve were obtained under different pulse width modulation(PWM)input control signals.Results show that,first of all,the new type of high-pressure solenoid valve can meet the switch requirement.Secondly,the opening movement and closing movement of the spool lags the PWM rising signal,and the coil current fluctuates significantly during the movement of the spool.Lastly,on/off status of high-pressure valve cannot be represented by the duty cycle.This research can be referred in the design of the high-pressure solenoid valve..展开更多
基金Supported by National Natural Science Foundation of China (Grant No.52005441)Young Elite Scientist Sponsorship Program by CAST of China (Grant No.2022-2024QNRC001)+4 种基金Zhejiang Provincial Natural Science Foundation of China (Grant No.LQ21E050017)Zhejiang Provincial“Pioneer”and“Leading Goose”R&D Program of China (Grant Nos.2022C01122,2022C01132)State Key Laboratory of Mechanical System and Vibration of China (Grant No.MSV202316)Fundamental Research Funds for the Provincial Universities of Zhejiang of China (Grant No.RF-A2023007)Research Project of ZJUT of China (Grant No.GYY-ZH-2023075)。
文摘The high-speed on/off valve(HSV)serves as the fundamental component responsible for generating discrete fluids within digital hydraulic systems.As the switching frequency of the HSV increases,the properties of the generated discrete fluid approach those of continuous fluids.Therefore,a higher frequency response characteristic of HSV is the key to ensure the control accuracy of digital hydraulic systems.However,the current research mainly focuses on its dynamic performance,but neglect its FRC.This paper presents a theoretical analysis demonstrating that the FRC of the HSV can be enhanced by minimizing its switching time.The maximum switching frequency(MSF)is mainly determined by opening dynamic performance when HSV operates with low switching duty ratio(SDR),whereas the closing dynamic performance limits the MSF when HSV operates with high SDR.Building upon these findings,the pre-excitation control algorithm(PECA)is proposed to reduce the switching time of the HSV,and consequently enhance its FRC.Experimental results demonstrate that PECA shortens the opening delay time of HSV by 1.12 ms,the closing delay time by 2.54 ms,and the closing moving time by 0.47 ms in comparison to the existing advanced control algorithms.As a result,a larger MSF of 417 Hz and a wider controllable SDR range from 20%to 70%were achieved at a switching frequency of 250 Hz.Thus,the proposed PFCA in this paper has been verified as an effective and promising approach for enhancing the control performance of digital hydraulic systems.
基金The research work presented in this paper is financially supported by a grant(NJZZ18139)from the scientific research project of Universities in Inner Mongoliaa grant(2018BS05003)from the Natural Science Foundation of Inner Mongoliaa grant(2017QDL-B07)from Inner Mongolia University of Science and Technology Innovation Fund Project.
文摘To improve energy density,the transportation,storage,and operations of hydrogen,methane,and compressed air vehicles currently require high-pressure compression.High-pressure solenoid valve becomes the vital element to above system.In order to reduce leakage and aerodynamic force influence,a new type high-pressure solenoid valve was proposed.The simulation model which included electromagnetic model,aerodynamic force model was established by means of the nonlinear mathematic models.Using the software MATLAB/Simulink for simulation,the dynamic response characteristics of high-pressure pneumatic solenoid valve were obtained under different pulse width modulation(PWM)input control signals.Results show that,first of all,the new type of high-pressure solenoid valve can meet the switch requirement.Secondly,the opening movement and closing movement of the spool lags the PWM rising signal,and the coil current fluctuates significantly during the movement of the spool.Lastly,on/off status of high-pressure valve cannot be represented by the duty cycle.This research can be referred in the design of the high-pressure solenoid valve..