Summary: | 碩士 === 國立臺灣科技大學 === 工程技術研究所自動化及控制學程 === 88 === Hydraulic valve-controlled systems have high response, so they often are used in hydraulic servo control systems. However, in the traditional hydraulic valve-controlled system, supply pressure is set as constant by a relief valve. The most serious disadvantage of such systems lies in the low energy efficiency. As the high pressure hydraulic oil supplied by pumps flow through direction valves, only a part of hydraulic energy is transferred into mechanical energy by hydraulic actuators. The additional hydraulic energy is transferred into heat to make the oil temperature rising. It makes both energy consuming which reduces the system efficiency and oil temperature rising which affects the system performance. In order to improve this problem, we make a hydraulic pump with variable displacement adjusting supply pressure automatically. That is, the supply pressure rises if external load increases. On the contrary, it becomes smaller automatically if external load reduces. Such a system is so-called ‘Load-sensing system’.
In this paper, we apply SOC(self-organizing controller)and ANFIS(adaptive network-based fuzzy inference system)to a closed-loop system and ARMA model to a system modification between input and output. During the control process, the rules and membership functions can be adjusted respectively automatically. By modeling and experiment, we prove that the result for pressure difference control on a nonlinear and load-varying system is satisfied.
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