HOIST MOTION CONTROL: HYDRAULIC SOLENOID VALVE CURRENT REGULATION AND IDENTIFICATION OF MINIMUM CURRENT FOR MOTION
Open Access
- Author:
- Devadoss, Daphny Oviya
- Graduate Program:
- Electrical Engineering
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- June 27, 2019
- Committee Members:
- Jeffrey Louis Schiano, Thesis Advisor/Co-Advisor
- Keywords:
- hoist control
PI controller
current regulation in solenoid valve
minimum current for hydraulic motion
averaging state-space model - Abstract:
- This thesis addresses two challenges in optimizing the operation of hydraulic systems on a boom crane. The first challenge is to develop an algorithm for choosing control gains for the proportional-integral controllers that regulate the average current in hydraulic solenoid cartridge valves. The second challenge is to develop an algorithm that determines the minimum average current Imin through a solenoid cartridge valve that produces motion in a hydraulic actuator. The proposed control algorithm achieves an over damped response with a rise-time of about a second in response to a step change in the commanded average current. In addition, the algorithm places the poles so that Imin is reached early during the one second rise-time. The minimum average current Imin required through the solenoid valve for hydraulic motion is affected by the solenoid valve parameters and the hydraulic motor coupling to the load. A binary search algorithm is proposed as it has a maximum complexity of O(log n), for the determination of Imin across different hydraulic mechanisms. The algorithms for determining control gains and Imin are validated using hardware-in-the-loop simulation and on a Grove Rough Terrain crane at the Manitowoc Product Verification centre located in Shady Grove, Pennsylvania. As the cranes are operated across various geographical locations with temperatures ranging from -40 deg F to 120 deg F, the effect of the temperature variation on the solenoid parameters and on the controller design is also studied.