P. Bussy

Sliding mode control based on field orientation for an induction motor

Sliding mode control is popular method for achieving robust tracking of nonlinear systems. The state is forced onto a manifold in state space by discontinuous control. This manifold is so that staying on it implies convergence to the state space origin. In this paper, the nonlinear sliding mode speed and flux control (SMC) based on field orientation for an induction motor drive is proposed, based on the transformed state coordinate representing the speed and flux magnitude dynamic. With the proposed control of speed and flux amplitude, the controlled induction motor drive possesses the advantages of robustness to parametric uncertainties and disturbances. Finally, some simulation results are given to validate the proposed controllers.

Design and implementation of Sliding Mode Controller with varying boundary layer for a coupled tanks system

In this paper, the nonlinear Sliding Mode Control (SMC) with varying boundary layers is implemented to improve the tracking performance of a nonlinear system. The key feature of the control scheme is the use of varying boundary layers instead of fixed boundary layers, which are usually employed in conventional SMC. The experimental results strongly suggest that the proposed control scheme is capable of improving the tracking precision without causing any chattering. In addition, the new control scheme seems to be very robust against various set point conditions.

Second order sliding mode induction motor control with a new Lyapunov approach

This paper, deals with the control and observation of an induction motor using second order sliding-mode technique. We present a new Lyapunov function for the stability analysis. This approach guarantees the same robustness and dynamic performance of traditional first-order SMC algorithms, and at the same time, attenuates the chattering phenomenon, which is the main drawback in the actual implementation of this technique. The magnitude of the rotor flux of the induction motor is determined by the output of the closed-loop rotor flux observer based on twisting algorithm control theory. This technique is proposed for the solution of chattering. Simulation results are presented to validate the effectiveness and the good performance of the proposed control technique.

Adaptive backstepping sliding mode control for hydraulic system without overparametrisation

advance practical applications. Therefore, an adaptive law is proposed to adapt the value of the lumped uncertainty in real time. The main novelty of the developed adaptive control laws is that the number of parameter estimates is exactly equal to the number of unknown parameters throughout the entire coupled tanks system. Consequently, the phenomenon of overparametrisation, a significant drawback of backstepping technique to treat the control of coupled tanks in the previous literature, is eliminated in this study. Finally, experimental results are given to illustrate the tracking performance of interconnected system with the developed adaptive control schemes.

Sliding mode control with integral corrector: Design and experimental application to an interconnected system

In this paper, a solution is proposed in order to solve the chattering avoidance problem in variable structure control for a class of uncertain non linear systems with external disturbances. This approach is based on Sliding Mode Control (SMC) with integral corrector in the boundary layer to synthesize a robust control system. The stability and the performances of the closed-loop system are proven analytically using the Lyapunov synthesis approach. The proposed methods attenuate the effect of both uncertainties and external disturbances; moreover it attenuates the chattering phenomenon introduced by classical sliding-mode control. The application of this method to the two-tank system illustrates the validity and the performances of this approach. The experimental results are presented and compared in this paper.

Robust control of the Photovoltaic system with improved maximum power point tracking

A robust voltage control intended for a photovoltaic system is considered. An improved maximum power points tracking (MPPT) is presented without Photovoltaic array characteristics known. In order to cope with large parameter variations and load disturbances, second order sliding mode controller, based on super twisting algorithm for DC-DC Boost converter is proposed. The designed control shows fast MPPT and good robustness with respect to parameter variations, measurement errors and unmodeled dynamics. The experimental results confirm the effectiveness of the proposed control.

Robust second order sliding mode controller for nonlinear hydraulic system

This paper deals with the robust control problem of two coupled tank subjected to parameters uncertainties and external disturbance. The Standard Sliding Mode (SSM) controller produces oscillations (or”chattering”) in the closed-loop system. The new approach High Order Sliding Mode (HOSM) is proposed to eliminate the undesired chattering effect by using the robust differentiator. The application of this method to the two-tank system illustrates the validity and the performances of our approach. The experimental results are presented and discussed in this paper.

Nonlinear sliding mode control with backstepping approach for a nonlinear three tank system

In this paper, the nonlinear sliding-mode control combined with the backstepping approach for a three tank system is proposed. The recursive nature of this approach is similar to the standard backstepping, and the difference is that we use backstepping to design virtual controller including a zero-order sliding mode at each recursive step. Stability analysis results are discussed, which show that the closed-loop system is ultimately bounded. The application of the proposed controller to a real three tank system is also presented; some results are included to demonstrate the good performance of the proposed controller.

A new second order sliding mode control approach for coupled MIMO nonlinear uncertain systems

The paper proposes a new second order sliding mode control (SOSMC) approach for coupled multi-input multi-output (MIMO) nonlinear uncertain systems. This proposed new SOSMC is designed by the choice of a judicious Lyapunov function which depends on the sliding surfaces and its derivative. This control can be applied to a large class of nonlinear coupled MIMO processes affected by uncertainties and disturbances. The applicability and the efficiency of our approach are illustrated by simulation results for an interconnected three-tank system.

Analysis and simulation of a 1.5 MVA doubly fed wind-power in MATLAB SimPowerSystems using crowbar during power systems disturbances

The performance of a 1.5 MVA wind-power doubly fed induction generator (DFIG) under network fault is studied using simulator developed in MATLAB-Simulink. The simulator consists of the DFIG analytical model, the detailed frequency converter model including passive crowbar protection, and model of the transformer. Simulation results show the transient behavior of the doubly fed induction generator when a sudden voltage dip is introduced with and without the crowbar implemented.