PI-type Iterative Learning Control for Nonlinear Electro-hydraulic Servo Vibrating System

Proceedings of the Institution of Mechanical Engineers, Part I:

Zhao

2013

In order to simulate the vibrating condition of composite insulators in breeze, and carry out its fatigue test under loading and vibrating conditions, the electro-hydraulic loading and testing technology for the composite insulators is researched in this study. A compound electro-hydraulic loading system is first designed, including two subsystems, the static proportional loading system and the dynamic servo loading system. Then, the working principle based on this system is analyzed, and the mathematic model of electro-hydraulic servo system is also built, proved to be an inertial element with high gain. The control method based on proportional-derivative-type iterative learning control has been applied to such a dynamic servo loading system, to achieve the high-precision control for dynamic load force with repetitive regularity. Both mathematic simulation and actual experiments have been designed and carried out, and their results proved that the load principle and the control method are feasible and applicable and have the ability of achieving high-precision control effects. Based on this discussed electro-hydraulic technology, an actual electro-hydraulic loading and testing system for different kinds of composite insulators has been researched and developed, with the advanced technology indices of six loading channels, 20 kN maximum dynamic force, 0.3 kN force control precision and 100 Hz maximum vibrating frequency.

Section: Control Methods Based On Ilcmentioning

confidence: 99%

Section: Mathematic Model Of Servo Loading Systemmentioning

confidence: 99%

See 1 more Smart Citation

A case study of electro-hydraulic loading and testing technology for composite insulators based on iterative learning control

Proceedings of the Institution of Mechanical Engineers, Part I:

Zhao

2013

“…Learning-based control is another very useful method for EHSs. Luo et al (2009), Zhao et al (2005) and Zheng et al (2010) used iterative learning control to implement the accuracy position control of a hydraulic system, and Yao et al (2015) proposed a repetitive learning method to deal with the non-linear problem of a hydraulic system. Learning-based methods can work well for the systems in which the reference input signal is regular.…”

Section: Introductionmentioning

confidence: 99%

The fractional order PI control for an energy saving electro-hydraulic system

Zhao

Transactions of the Institute of Measurement and Control

2015

In an electro-hydraulic system (EHS), the throttling phenomenon of the hydraulic valve leads to the problem of low utilization efficiency of hydraulic energy and severe increases in temperature. To alleviate this problem, this paper presents a type of one-chamber-controlled hydraulic circuit. In some applications where elastic load is dominant, this hydraulic circuit can achieve a significant energy-saving effect. For a valve-controlled system, the orifice non-linearity and the slowly varying parameter significantly influence the control performance of the electro-hydraulic system. With this aim in mind, the orifice compensation method is proposed to deal with the orifice non-linearity. Based on the compensation, the fractional order proportional–integral (FOPI) controller is adopted to deal with the problem of fluid parameter variation. In the controller designing process, this paper proposes a controller parameter tuning method based on system frequency characteristic data. Simulation and experiment results show that the strategy presented in this paper can reduce the energy losses dramatically and, at the same time, the control performance of electro-hydraulic system can be guaranteed.

“…15 ILC is also a low-complexity and robust controller for identification, model reduction, and controller reduction of higher order systems, which can meet real-time control requirement of motion control systems. 12 Therefore, ILC has provided a feasible solution for the control issues of vibration simulation.…”

Section: Controller Design For Composite Actuatormentioning

confidence: 99%

Design and control of a hydraulic composite actuator for vibration simulation

Xuan

Advances in Mechanical Engineering

Liu

2018

A hydraulic composite actuator is developed for vibration simulation. The hydraulic scheme and control principle are introduced and an open-closed-loop iterative learning control method is proposed for control issue. A special composite cylinder controlled by servo valve and proportional relief valve is designed to generate static force with large amplitude and dynamic force with small amplitude but high frequency. The control subsystem for dynamic force is a zero-type system with very high open-loop gain and uncertainty of parameters; therefore, an open-closed-loop proportional-derivative-type iterative learning control scheme is designed to solve this challenging control issue. A principle prototype of this hydraulic has been developed, and the experiments have been designed for this actuator. Different control methods are experimented for verification and comparison, and experiment results have verified practical applicability of this actuator and the superiority of control scheme.