Energy-Efficient Robust Control for Direct Drive and Energy Recuperation Hydraulic Servo System

Abstract

During the vertical cyclic actuation process of heavy materials handling, the gravitational potential energy will be converted to heat in the form of throttle in the traditional hydraulic system. Therefore, large energy dissipation is inevitable is this process. In order to achieve energy recuperation, as well as precise trajectory tracking, a direct drive and energy recuperation system is developed. To be specific, the function of direct drive and energy recovery is realized via the three-chamber actuator and a hydraulic accumulator. Moreover, the optimized parameters are obtained by the simulated annealing algorithm. To further reduce the energy consumption, the variable supply pressure control circuit is introduced into the system. Furthermore, the prescribed tracking performance is guaranteed by the proposed robust controller. To compensate for the uncertainties, both in the variable supply pressure control circuit and the robust controller, the RBF neural network is employed to approximate the unknown function. The presented approach theoretically possesses the ability to minimize the energy consumption while maintaining satisfied tracking accuracy. The results demonstrate that the proposed approach can save nearly 90 percent of the energy, and the maximum tracking error is 2 mm.

Output feedback motion control of pneumatic servo systems with desired compensation approach

“…According to the mean value theorem of multivariate function and noting (28), (31), one obtains where x 2 is a value between ̇x d and x 2 , and x 3 is a value between ẍ d and x 3 , It can be seen from (38) and (39) that the extent of N 1 and N 2 can be made arbitrarily small by tuning the gains of the proposed ESMO and robust controller.…”

“…However, numerous parameter-adaptive algorithms in the literature depend on the measurable system states such as the RBF neural network-based algorithms [31] and least square method [32], which is not applicable in output feedback system. Hence, in this study, a desired compensation indirect-type estimation method based on physical model and desired system states is designed to achieve parameter estimates, which can be regarded as an offline compensation component.…”

Optimal Control for a Hydraulic Recuperation System Using Endoreversible Thermodynamics

“…For achieving the global goal of reduced fossil fuel consumption and CO 2 emissions the automotive sector plays an important role. In particular, energy recovery systemselectrical, mechanical or hydraulic-are an effective approach to use otherwise wasted energy and improve the vehicles overall efficiency [1][2][3][4][5][6][7][8][9]. The starting point of this work is a research project that focuses on hydraulic recuperation systems for medium and heavy commercial vehicles with tipper bodies.…”