Experimental Research On Hydraulic Cylinder Precision Drive Unit

With the advance of modern science and technology,computer technology, sensor technology and automatic control technology development, motor-driven approach has achieved obvious advantages in terms of location precision control of mechanical actuators.But with the magnetic material of magnetic saturation properties influence, the output capacity of the precision driving motor is relatively limited.Hydraulic driving has been known as Hercules and has a unique advantage in terms of power output.therefore, the use of a hydraulic drive system for precise position control has become a research hotspot. At present, the technology achieved by high precision hydraulic driving are mainly the servo control and direct digital control, servo control system is expensive, the media demanding and high failure rate; direct digital control of position precision is high, but by the mechanical structure and the step motor power constraints, can not meet the high pressure and large bore hydraulic system requirements.In view of the existing hydraulic cylinder precision control problems, put forward the concept of volume intrusive control, research to produce a "precision hydraulic cylinder drive unit", and the practical requirements of "long time stable decompression" and "stepping micro stroke control" and "travel of precision control performance was experimentally verification.Drive unit" with PLC controller, use displacement, pressure sensor for signal feedback to realize the closed-loop control of the step motor driven auxiliary fuel tank. This paper describes the theoretical basis of the principle of "precision hydraulic cylinder drive unit" can achieve high control accuracy, and built-intrusive control volume concept, introduced the principle structure "precision hydraulic cylinder drive unit," describes the experimental verification process and control methods, and the results were analyzed.The research results show that the "hydraulic cylinder precision drive unit" as hydraulic independent function modules, can achieve the precision control of the hydraulic cylinder speed, pressure, position,which is suitable for various specifications of hydraulic equipment,compared with the system using the hydraulic servo valve has the advantages of low cost,high rigidity, strong adaptability to the environment, energy utilization reasonable, high control precision.