抄録
Recently, highly energy efficient products have become more and more valuable. However, in hydraulic excavators, saving energy sometimes causes hunting. Here, excavators have Pressure-Displacement Capacity Control (P-Q Control). The purpose of this study is designing a control system to suppress hunting with highly efficient. In this paper, the hydraulic system is first modeled to clarify the reason of hunting, and P-Q Control is changed for PID control which can compensate delay time. Furthermore, PID parameters are determined based on closed loop data. To calculate PID parameters without simulator, modeling error is excluded.