Abstract The electro-hydraulic servo system (EHSS) usually faces multiple sensor faults and disturbances, which is difficult to achieve good tracking control, reliability, stability control. In this article, an advanced fault-tolerant controller proposed for EHSS deal with the above challenge. three fault observers, called nonlinear unknown input observers (NUIOs), are developed effectively est...

In order to study the numerical control (NC) servo press hydraulic control system and its control algorithm. The numerical control servo press performance and control principle of hydraulic control system are analyzed. According to the flow equation of the hydraulic control valve, hydraulic cylinder flow continuity equation and the force balance equation of the hydraulic cylinder with load pres...

The paper aims to develop a novel pitch control system for a large wind turbine driven by a variable-speed pump-controlled hydraulic servo system. To perform practical pitch control experiments, a full-scale test rig of the hydraulic pitch control system for a 2 MW wind turbine’s blade, including a novel pitch control mechanism, a variable-speed pump-controlled hydraulic servo system, a disturb...

In this paper, a fault management system for a hydraulic servo axis is described. This system is capable of sustaining faults in the piston displacement sensor of the position-controlled hydraulic servo axis. By means of a parity equation based fault detection stage, faults in the displacement sensor as well as other sensors and components of the servo axis can be detected and subsequently be d...

In this paper, a new control method based on FEL electro hydraulic servo control withnonlinear flux and internal friction, has been presented. The new approach based oncontrollers combined by a classic PD controller and a fuzzy controller is smart. This newtechnique has a good ability to control the performance and stability. Simulations have beencarried out in Matlab environment and the result...

In this paper the control problem of a hydraulic servo-system is addressed. The performance achievable by classical linear controllers, e.g. PD, are usually limited due to highly nonlinear behavior of the hydraulic dynamics. This paper adopts the backstepping design strategy to develop a Lyapunov-based nonlinear controller for a hydraulic servo-system. Load, hydraulic and valve dynamics are inc...

This chapter utilizes the direct neural control (DNC) based on back propagation neural networks (BPN) with specialized learning architecture applied to the speed control of DC servo motor. The proposed neural controller can be treated as a speed regulator to keep the motor in constant speed, and be applied to DC servo motor speed control. The proposed neural control applied to position control ...

This paper will address two issues associated with the implementation of a hydraulically powered dissimilar muster-slave teleoperated system. These issues are the overall system control architecture and the design of robust hydraulic servo controllers for the position control problem. Finally, a discussion of overall system performance on an actual teleoperated system will be presented. (Schill...

The conventional hydraulic valve-controlled systems have high response but low energyefficiency. Hydraulic pump-controlled servo systems have high energy efficiency. However, the conventional pump-controlled systems, which are altered by displacement via variable displacement pumps, have lower response. This paper aims to investigate the force control performance of the high response electro-hy...

Servo-hydraulic control is regarded as a key technology in most mechanical testing systems for the investigation of strength and fatigue properties of materials, mechanical components and structures. High performance but robust control strategies are necessary as part of the test control system to ensure high test quality and reproducible test results which are of special importance when consid...