Pressure Margin Controllable Pre-compensated Load Sensing System with Variable Speed-fixed Displacement Pumps for Electric Construction Machinery

doi:10.3901/JME.2025.22.355

Abstract

Abstract: The development of electrification and intelligence of construction machinery has put forward higher requirements for energy saving and maneuverability of load sensing system. Aiming at the problems of the conventional load sensing system, such as the lack of anti-flow saturation function of pre-compensated type, the extra energy consumption of post-compensated type, and the fixed setting of the pressure margin, a pressure margin controllable pre-compensated load sensing system with variable speed-fixed displacement pumps is proposed, and the variable speed-pressure margin regulation and anti-flow saturation control strategies are further designed, and simulation and experimental studies are carried out. The results show that,① the proposed system has good anti-flow saturation characteristics;② the proposed system can be operated at different pressure margins to obtain variable flow gains to avoid the system from entering flow saturation, and the effective control stroke of the main spool has been improved to have better fine-tuning and flow control characteristics compared with the LUDV system;③ The proposed system eliminates additional commutation throttling losses and reduces orifice throttling losses compared to the LUDV system, resulting in a reduction in system energy consumption of 6.3% to 13.7% at different actuator speed conditions.

Key words: load sensing, electric construction machinery, pre-compensation, anti-flow saturation, variable speed control, variable pressure margin control

CLC Number:

TH137

LIN Yuanzheng, LIN Tianliang, LI Zhongshen, MIAO Cheng, CHEN Qihuai, ZHAO Heng, SHI Jiarong. Pressure Margin Controllable Pre-compensated Load Sensing System with Variable Speed-fixed Displacement Pumps for Electric Construction Machinery[J]. Journal of Mechanical Engineering, 2025, 61(22): 355-369.

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