Composite Pressure Control Method of Electro Hydraulic Power Source Based on Pressure Closed Loop Feedback and Speed Compensation

doi:10.3901/JME.260203

Abstract

Abstract: Pressure control is achieved by driving a fixed-displacement pump via servo motor torque control, offering faster dynamic response compared to variable speed pressure control. In torque-controlled electro-hydraulic power sources, reliance on pressure sensor feedback is typically required within a closed loop to maintain output pressure accuracy. Failure of the sensor causes significant pressure control deviation due to the nonlinear mapping relationship between torque and pressure. To address this, a compound pressure control method integrating pressure closed-loop feedback and speed compensation is proposed. During normal operation, pressure is regulated through the pressure closed loop. Upon pressure sensor failure, compensation control is implemented utilizing the servo motor's built-in speed feedback to sustain pressure control accuracy. Theoretical analysis and experimental validation demonstrate that the proposed scheme enables high-precision pressure control. When a pressure sensor fault occurs, the speed compensation control within the scheme effectively maintains the power source's output pressure accuracy, reducing the control deviation from 20% to approximately 2%.

Key words: electro-hydraulic power source, torque control, pressure control, speed compensation

CLC Number:

TH137

YANG Fei, ZHAO Lei, GE Lei, WANG Xiaohu, QUAN Long, XIONG Xiaoyan. Composite Pressure Control Method of Electro Hydraulic Power Source Based on Pressure Closed Loop Feedback and Speed Compensation[J]. Journal of Mechanical Engineering, 2025, 62(6): 400-408.

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URL: http://www.cjmenet.com.cn/EN/10.3901/JME.260203

http://www.cjmenet.com.cn/EN/Y2025/V62/I6/400

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