Title: Valve-pump parallel control of hydraulic motor speed servos with large power

Authors: Haigang Ding; Jiyun Zhao

Addresses: School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou 221116, China; Department of Mechatronic Engineering, Xuzhou College of Industrial Technology, Xuzhou 221140, China ' School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou 221116, China

Abstract: This study proposes both replenishing type and leaking type valve-pump parallel controlled systems, and then establishes their mathematical principle models and simulated numerical models. Comparative analysis of performances and parameters of the pump controlled system and valve-pump parallel controlled system indicate that the proposed systems can respond faster with high efficiency than the pump controlled systems, just because the valve responds more rapidly than the variable pump and works at low flow status; total leakage coefficients and damping ratios of the proposed system are large and vary widely with the valve opening and load pressure. When suffering disturbance of variable loads, the replenishing type system has more stable damping ratios and speed stiffness compared with the leaking type system. In addition, it can further improve response and speed stiffness by raising the supply pressure of the controlled valve, while the leaking type system does not have this flexibility. Therefore, the replenishing type valve-pump parallel control is more suitable for hydraulic speed servo systems with large power to achieve rapid response and good speed stiffness with high efficiency.

Keywords: valve pumps; parallel control; rapid response; speed stiffness; efficiency; variable displacement pumps; proportional valve; hydraulic motors; motor speed servos; mathematical modelling; numerical simulation.

DOI: 10.1504/IJMIC.2014.062021

International Journal of Modelling, Identification and Control, 2014 Vol.21 No.4, pp.339 - 351

Published online: 23 Aug 2014 *

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