April 2024
·
13 Reads
This page lists the scientific contributions of an author, who either does not have a ResearchGate profile, or has not yet added these contributions to their profile.
It was automatically created by ResearchGate to create a record of this author's body of work. We create such pages to advance our goal of creating and maintaining the most comprehensive scientific repository possible. In doing so, we process publicly available (personal) data relating to the author as a member of the scientific community.
If you're a ResearchGate member, you can follow this page to keep up with this author's work.
If you are this author, and you don't want us to display this page anymore, please let us know.
April 2024
·
13 Reads
August 2023
·
1 Read
July 2023
·
144 Reads
Axioms
There is a permanent and strong need for energy recovery to improve the efficiency of the hydraulic system in the field of the construction machinery. In addition, the digital pump will become powerful and versatile by employing different configurations and intelligent control of the flow distribution valves. Considering this case, we have proposed a novel digital pump in which every plunger is equipped with two flow distribution valves. By controlling these two valves, external hydraulic energy can be directly reused without other components. Based on the structure and working principle of the digital pump, the mathematical model is established and three working modes are detailed. To verify the feasibility and correctness of control methods, a performance simulation testing platform including a digital pump, load module, hydraulic energy to be recovered, and controller module was developed in AMESim R15 software. The pressure, flow rate, and torque simulations of the digital pump in three working modes were carried out. The simulation results have shown that the digital pump not only can be used as an ordinary pump but also has the function of recovery and immediate reutilization of another hydraulic energy. Meanwhile, the corresponding variable displacement control strategy is effective and the positive torque required to drive the digital pump can be reduced, which verified the energy-saving of this scheme. The ideas and contents in this paper can offer significant references for energy conservation technology of various engineering machineries and the intensive study of digital hydraulics.
January 2023
·
132 Reads
·
1 Citation
Perfect flow distribution is extremely important and essential for digital pumps. However, the fluctuation of motor speed and the change of valve dynamic characteristics cause the flow distribution flaw, which generates the backflow of the oil in the piston chamber and the decrease in pump volumetric efficiency. Based on the three-dimensional and mathematical modeling of the digital pump, the perfect distribution state of the digital pump is analyzed. Then, the adverse effects of the variations in motor speed and valve dynamic characteristics on the flow distribution of the digital pump were simulated and investigated by the software AMESim. To overcome the aforementioned problems, we proposed an adaptive control method for the flow distribution valve of a digital pump, which was realized by adopting the axis rotation angle and the pressure difference between the inlet and outlet of the flow distribution valve. The results show that the control signal of the flow distribution valve can be regulated automatically along with the motor speed and the valve dynamic characteristics, achieving the ideal flow distribution of the digital pump designed in this paper. The study can be used as a reference for the optimal design and prototype manufacturing of the digital pump.
January 2022
·
125 Reads
·
8 Citations
Digital hydraulic technology as an emergent and important branch of fluid power offers good prospects for intelligence, integration, and energy saving of hydraulic systems. The high-speed on-off valve (HSV) that is a critical component of digital hydraulics has the drawbacks of specific design, narrow scope of application and high price compared to the commercial solenoid screw-in cartridge valve (SCV) widely used in the hydraulic industry at present. In this paper, a hybrid voltage control strategy composed of the preloading voltage, positive pulse voltage, holding voltage and negative pulse voltage is proposed to enhance the dynamic characteristics of the SCV, which makes it meet the demands of the digital hydraulics and achieve the end of replacing the HSV. Based on the structural analysis of the SCV, a mathematical model of the SCV is deduced. Subsequently, the simulation model of the SCV is developed in AMESim and validated by experimental measurements. The effects of the different duty ratios of the preloading voltage and holding voltage on the dynamic characteristics of SCV are studied, and the dynamic responses of the SCV under the normal voltage, positive and negative pulse and hybrid voltage control strategies are compared. The simulation results indicate that the increment of the preload voltage duty ratio and the reduction of the holding voltage duty ratio are conducive for decreasing the total opening and closing time of the SCV, especially the opening delay and closing delay time. The hybrid voltage control proposed has a better effect in dynamic characteristics than the other two strategies, using which the total opening time of the SCV reduces by 74.24% (from 29.5 ms to 7.60 ms), and the total closing time is drastically squeezed by 92.06% (from 136 ms to 10.8 ms). This provides a technical reference for improving the dynamic response speed of SCVs and popularizing digital hydraulic technology.
September 2021
·
83 Reads
·
9 Citations
Processes
The hydraulic high-speed on/off valve (HSV)—the critical core component of digital hydraulic technology—has a special structural design and manufacture due to its fast opening and closing, which results in high prices and maintenance costs. The solenoid screw-in cartridge valve (SCV) is widely used in the hydraulic industry because of its merits, such as mature technology, reliable quality, and low cost. The contribution of this study is to replace the high-speed on/off valve with the SCV in some areas of application by introducing positive and negative pulse voltage control for the coil of the SCV, which only modifies the control circuit and needs no change in structure. Based on the analysis of the structure of the SCV, the simulation model was developed in AMESim and validated by experiments to investigate the effects of the pulse voltage duration on the open–close dynamic characteristics and find the optimal pulse voltage duration, so that the SCV can open or close in the shortest time to reduce energy loss as far as possible. The simulation results showed that the positive and negative pulse voltage could quicken the rising or declining speed of the coil current and dramatically decrease the opening and closing delay time. By the experimental comparison with the original control method, the opening time of the SCV decreased from 30 ms to 13 ms, and the closing time was reduced from 139 ms to 14 ms.
... The two pumping cylinders alternately extend and retract to drive the concrete cylinders to suck and deliver concrete. The swing cylinder drives the distribution valve to swing and connects it to the concrete cylinder that pumps concrete [22]. The signal valves are used to sense the displacement of the pumping cylinders and provide a control signal to reverse the swing cylinder, so the signal valve is the unit that connects the pumping mechanism to the swing mechanism. ...
January 2023
... Two-stage proportional cartridge valves are used in such applications. Two-stage proportional cartridge valves with a poppet-type construction, which give better sealing compared with the traditional large flow proportional cartridge valve, have been succesfully used in large-flow, fast-response, and high-pressure applications [12,13]. ...
January 2022
... A directional control valve with a three-stage structure based on two high-speed on/off solenoid valves as the pilot stage and two poppet-type cartridge valves as the secondary stage was proposed in [21] to get a fast response and maximize the flow and pressure. Daling Yue et al. (2021) proposed a control strategy based on optimizing the duty ratios of positive and negative pulse voltages to decrease the opening and closing times of a screw-in cartridge valve [22]. The same research group further developed optimizations in the opening and closing times of a valve by proposing a hybrid voltage control strategy in which a preload voltage and hold voltage stage were added to the positive pulse and negative pulse voltages [13]. ...
September 2021
Processes