PSEUDO-PROPORTIONAL POSITION CONTROL OF WATER HYDRAULIC CYLINDER USING ON/OFF VALVES
- Resource Type
- Journal Article
- Authors
- Kari T. KOSKINEN; Matti LINJAMA; Matti VILENIUS
- Source
- Proceedings of the JFPS International Symposium on Fluid Power. 2002, 2002(5-1):155
- Subject
- Water hydraulics
on/off control
pulse code modulation
- Language
- English
- ISSN
- 2185-6303
The paper studies the possibility to replace expensive water hydraulic proportional valve with a number of low-cost on/off valves. A position control system of a water hydraulic cylinder is realized with eight two-way solenoid valves and one four-way on/off valve. A pulse code modulation is used to achieve almost proportional control. A position controller based on multi-rate sampling is developed to minimize position error. Experimental results with a high inertial load show smooth movements, 0.2mm position accuracy and 200mm/s maximum velocity. The advantages and disadvantages of the on/off valve system are discussed.