Particle Swarm Method-Based Hyperbolic Sliding Mode Control Strategy for the Optimal Design of Parallel-Connected UPS Systems

Abstract Building structures are prone to damage due to natural disasters, and this challenges structural engineers to design safer and more robust building structures. This study is conducted to prevent these consequences by implementing a control strategy that can enhance a building's stability and reduce the risk of damage. Therefore, to realize the structural integrity of a building, a hybrid control device is equipped with control strategies to enhance robustness. The control strategy proposed in this study is adaptive nonsingular terminal sliding mode control (ANTSMC). ANTSMC is an integrated controller of radial basis function neural network (RBFNN) and nonsingular terminal sliding mode control (NTSMC), which has a fast dynamic response, finite-time convergence, and the ability to enhance the control performance against a considerable uncertainty. The proposed controller is designed based on the sliding surface and the control law. The building with a two-degree-of-freedom (DOF) system is designed in Matlab/Simulink and validated with the experimental work connected to the LMSTest.Lab software. The performance of this controller is compared with those of the terminal sliding mode control (TSMC) and NTSMC in terms of the displacement response, sliding surface, and the probability of damage. The result showed that the proposed controller, ANTSMC can suppress vibrations up to 46%, and its percentage probability of complete damage is 15% from the uncontrolled structure. Thus, these findings are imperative towards increasing the safety level in building structures and occupants, and reducing damage costs in the event of a disaster.

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Super-Twisting Second-Order Sliding Mode Control of a Wind Turbine Coupled to a Permanent Magnet Synchronous Generator

International Journal of Intelligent Engineering and Systems ◽

10.22266/ijies2021.0228.45 ◽

2021 ◽

Vol 14 (1) ◽

pp. 484-495

Author(s):

Rania Moutchou ◽

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Ahmed Abbou ◽

Salah Rhaili ◽

◽

...

Keyword(s):

Sliding Mode Control ◽

Wind Turbine ◽

Permanent Magnet ◽

Control Strategy ◽

Sliding Mode ◽

Synchronous Generator ◽

Second Order ◽

Permanent Magnet Synchronous Generator ◽

Mode Control ◽

Second Order Sliding Mode

This paper presents a modelling study and focuses on an advanced higher order slip mode control strategy (Super Twisting Algorithm) for a variable speed wind turbine based on a permanent magnet synchronous generator to capture the maximum possible wind power from the turbine while simultaneously reducing the effect of mechanical stress, powered by a voltage inverter and controlled by vector PWM technique. This paper presents first and second order sliding mode control schemes. On the other hand, a challenging matter of pure SMC of order one can be summed up in the produced chattering phenomenon. In this work, this issue has been mitigated by implementing a new control. The proposed control, characterized by a precision in the case of a continuation of a significant reduction of the interference phenomenon, successfully addresses the problems of essential non-linearity of wind turbine systems. This type of control strategy presents more advanced performances such as behaviour without chattering (no additional mechanical stress), excellent convergence time, robustness in relation to external disturbances (faults in the network) and to non-modelled dynamics (generator and turbine) which have been widely used in power system applications by first order sliding mode control. In particular, second-order sliding regime control algorithms will be applied to the PMSG to ensure excellent dynamic performance. The suggested control is compared to the proportional-integral controller and sliding mode control of order one. The results of simulations under turbulent wind speed and parameter variations show the efficiency, robustness and significantly improved performance of the proposed control approach to distinguish and track quickly (about 10ms depending on the shading pattern) and at the same time saving the main priorities of the sliding mode of order one by reducing the existing chatter. The systems performances were tested and compared using Matlab/Simulink Software.

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Design of Composite Disturbance Observer and Continuous Terminal Sliding Mode Control for Piezoelectric Nanopositioning Stage

Electronics ◽

10.3390/electronics10182242 ◽

2021 ◽

Vol 10 (18) ◽

pp. 2242

Author(s):

Pengyu Qiao ◽

Jun Yang ◽

Chen Dai ◽

Xi Xiao

Keyword(s):

Sliding Mode Control ◽

Control Strategy ◽

Disturbance Observer ◽

Sliding Mode ◽

Accurate Estimation ◽

Terminal Sliding Mode Control ◽

External Disturbances ◽

Terminal Sliding Mode ◽

Composite Control ◽

Mode Control

The nonlinearities of piezoelectric actuators and external disturbances of the piezoelectric nanopositioning stage impose great, undesirable influences on the positioning accuracy of nanopositioning stage systems. This paper considers nonlinearities and external disturbances as a lumped disturbance and designs a composite control strategy for the piezoelectric nanopositioning stage to realize ultra-high precision motion control. The proposed strategy contains a composite disturbance observer and a continuous terminal sliding mode controller. The composite disturbance observer can estimate both periodic and aperiodic disturbances so that the composite control strategy can deal with the disturbances with high accuracy. Meanwhile, the continuous terminal sliding mode control is employed to eliminate the chattering phenomenon and speed up the convergence rate. The simulation and experiment results show that the composite control strategy achieves accurate estimation of different forms of disturbances and excellent tracking performance.

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