A mathematic model is built up to analyze the influences of a pilot valve'sleakage on the performances of pneumatic pressure proportional valve, and the performances aresimulated by using MATLAB. The results indic...A mathematic model is built up to analyze the influences of a pilot valve'sleakage on the performances of pneumatic pressure proportional valve, and the performances aresimulated by using MATLAB. The results indicate that using slide pilot valve in the valve system isfeasible, but the leakage's influences can not be neglected, especially it may induce instability ina low output pressure situation. A pilot valve using too large throttle window will cause the valveoscillate. To improve the working condition of pilot valve, a method adopting different widths oftwo throttle window is proposed. According to our simulation, this method balances the pressure dropbetween the two stage throttle ports, and reduces the influences of pilot valve's leakage.展开更多
Hydro-pneumatic suspension is widely used in heavy vehicles due to its nonlinear characteristics of stiffness and damping. However, the conventional passive hydro-pneumatic suspension can’t adjust parameters accordin...Hydro-pneumatic suspension is widely used in heavy vehicles due to its nonlinear characteristics of stiffness and damping. However, the conventional passive hydro-pneumatic suspension can’t adjust parameters according to the complicated road environment of heavy vehicles to fulfill the requirements of the vehicle ride comfort. In this paper, a semi-active hydro-pneumatic suspension system based on the electro-hydraulic proportional valve control is proposed, and fuzzy control is used as the control strategy to adjust the?damping force of the semi-active hydro-pneumatic suspension. A 1/4?semi-active hydro-pneumatic suspension model is established, which is co-simulated with AMESim and MATLAB/Simulink. The co-simulation results show that the semi-active hydro-pneumatic suspension system can significantly reduce vibration of the vehicle body, and improve the suspension performance comparing with passive hydro-pneumatic suspension.展开更多
Pneumatic proportional control servo regulator is the core component of a pneumatic-loading experimental system,which is very important in solving the overcharging problem.However,previous research on control of pneum...Pneumatic proportional control servo regulator is the core component of a pneumatic-loading experimental system,which is very important in solving the overcharging problem.However,previous research on control of pneumatic proportional regulator in a pneumatic-loading experimental system led to failure in analysis of the influence of opening error of the switch regulator because it did not analyze the regulator basic working principle and process.The traditional control method cannot fully solve the overcharging problem nor ensure adequate control performance of the regulator.After seriously studying the working principle and key mechanical parameters of the valve,a fuzzy parameter-adaptive controller is designed by introducing a linear mixture of the pressure and opening errors of the switch regulator to reduce pressure overshoot and optimize its control performance.According to the fuzzy-control strategy based on the working characteristics and mechanical parameters of the valve,the overshoot phenomenon of the pneumatic-loading system is solved,and the pressure overshoot is eliminated.The error of the output air pressure of the regulator is 1.24%,which is small.The adjustable pressure range of the regulator is 0.2–0.6 MPa.The maximum deviation is 0.012 MPa.The linearity of the case is 1.34%F.S.展开更多
基金This project is supported by National Natural Science Foundation of China (No.50122115)the National 10th Five Years Plan Special Research Programs of China(No.2003BA408B14).
文摘A mathematic model is built up to analyze the influences of a pilot valve'sleakage on the performances of pneumatic pressure proportional valve, and the performances aresimulated by using MATLAB. The results indicate that using slide pilot valve in the valve system isfeasible, but the leakage's influences can not be neglected, especially it may induce instability ina low output pressure situation. A pilot valve using too large throttle window will cause the valveoscillate. To improve the working condition of pilot valve, a method adopting different widths oftwo throttle window is proposed. According to our simulation, this method balances the pressure dropbetween the two stage throttle ports, and reduces the influences of pilot valve's leakage.
文摘Hydro-pneumatic suspension is widely used in heavy vehicles due to its nonlinear characteristics of stiffness and damping. However, the conventional passive hydro-pneumatic suspension can’t adjust parameters according to the complicated road environment of heavy vehicles to fulfill the requirements of the vehicle ride comfort. In this paper, a semi-active hydro-pneumatic suspension system based on the electro-hydraulic proportional valve control is proposed, and fuzzy control is used as the control strategy to adjust the?damping force of the semi-active hydro-pneumatic suspension. A 1/4?semi-active hydro-pneumatic suspension model is established, which is co-simulated with AMESim and MATLAB/Simulink. The co-simulation results show that the semi-active hydro-pneumatic suspension system can significantly reduce vibration of the vehicle body, and improve the suspension performance comparing with passive hydro-pneumatic suspension.
基金supported by the China Postdoctoral Science Foundation(Grant No. 2019M660392)the Open Research Project of the State Key Laboratory of Media Convergence and Communication, Communication University of China (Grant No. SKLMCC2020KF002)the National Key Research and Development Project (Grant Nos. 2019YFC0121700,2021YFC0122502)
文摘Pneumatic proportional control servo regulator is the core component of a pneumatic-loading experimental system,which is very important in solving the overcharging problem.However,previous research on control of pneumatic proportional regulator in a pneumatic-loading experimental system led to failure in analysis of the influence of opening error of the switch regulator because it did not analyze the regulator basic working principle and process.The traditional control method cannot fully solve the overcharging problem nor ensure adequate control performance of the regulator.After seriously studying the working principle and key mechanical parameters of the valve,a fuzzy parameter-adaptive controller is designed by introducing a linear mixture of the pressure and opening errors of the switch regulator to reduce pressure overshoot and optimize its control performance.According to the fuzzy-control strategy based on the working characteristics and mechanical parameters of the valve,the overshoot phenomenon of the pneumatic-loading system is solved,and the pressure overshoot is eliminated.The error of the output air pressure of the regulator is 1.24%,which is small.The adjustable pressure range of the regulator is 0.2–0.6 MPa.The maximum deviation is 0.012 MPa.The linearity of the case is 1.34%F.S.
