Stability Analysis of Backstepping Controller on Electrohydraulic System Using Disturbance Observer Mechanism

Abstract

In this research, the stability analysis of a backstepping controller on electro-hydraulic system using disturbance observer mechanism is presented. The proposed controller employs the parameter adaptation law designed according to Lyapunov analysis to guarantee the stability of the close loop system and the boundedness of the parameters, which is supported by the theorem. The materials used for this research include, Data from Electro hydraulic system, Matlab software and Computer system. The hydraulic system was built using Sim Hydraulic blocks imported from Matlab and the responses were analyzed from Matlab graph. The piston position was directly proportional to the Pump pressure where the hydraulic and spring forces were balanced. Discontinuities in the velocity at 0.04 sec and 0.05 sec indicates negligible mass of the piston. The model reaches a steady state when all the pump flow goes to leakage, this results to pressure drop across the control valves and brings about equal pressure at different locations of the valves. From the analysis, the position of the piston due to leakages was relatively poor. On implementation of disturbance observer the position tracking performance of the electro-hydraulic system was improved. The research concludes that the backstepping control using disturbance observer mechanism technique provided robust performance in the operation of electro-hydraulic system.