Super-twisting Sliding Mode Control Strategy Research Articles

Improved super-twisting sliding mode control strategy in permanent magnet synchronous motors for hydrogen fuel cell centrifugal compressor

This paper rigorously addresses the intricate control demands of high-speed, high-pressure, wide adjustable speed range, and high energy utilization efficiency required in hydrogen fuel cell centrifugal compressor, with a focus on the speed control of 40,000 RPM permanent magnet synchronous motors (PMSMs). An improved second-order super twisting sliding mode control (STSMC) strategy is proposed to enhance system stability and robustness by integrating the beetle antennae search (BAS) algorithm and grey wolf optimization (GWO) algorithm. The global search capability of BAS is used to improve the local optima issues of GWO, and then the improved GWO algorithm is utilized to address the issues related to parameter selection and convergence speed inherent in the STSMC. Theoretical validity of the proposed strategy is asserted through Quadratic Lyapunov Function, and its practicality is affirmed by thorough simulation. Comparative analyses are conducted with PI controller, traditional Sliding Mode Controller (SMC), and standard Super-Twisting Sliding Mode Controller (ST) under several case studies to show the superiority of the propose STSMC.

Distributed total-amount optimal coordinated control of multi-motors with input and output saturation

Specific to the double saturation constraints of input and output in multimotor network systems, an anti-windup control framework with distributed total-amount optimal coordination is constructed, and a new saturated super-twisting sliding mode control strategy is designed in this paper. First, a mathematical model of direct torque and flux control of a multipermanent magnet synchronous motor is established. Next, the consistency of the total amount and output saturation are taken as the constraint conditions. Considering the lowest total energy consumption, the optimal multi-axis total-amount coordinated allocation algorithm is designed on the basis of the Karush-Kuhn-Tucker (KKT) condition. Then, the input saturation is introduced into the dynamic integral part of the super-twisting algorithm. A new saturated super-twisting sliding mode tracking control algorithm is designed, and the barrier Lyapunov function is used to prove the input constraint. Finally, the Matlab/Simulink simulation and RT-LAB semi-physical experiments verify that the anti-windup control strategy of distributed total-amount optimal coordination can effectively solve the double saturation constraints of input and output.

Finite‐time super twisting sliding mode controller based on higher‐order sliding mode observer for real‐time trajectory tracking of a quadrotor

The main focus of this study is to develop a finite-time super-twisting sliding mode control strategy for the quadrotor based on a higher-order sliding mode observer (HOSMO). 12 state variables are required to describe the motion of the quadrotor, of which six state variables, namely the position, altitude, and orientation, are assumed to be obtained from the sensors. The remaining state variables, i.e. the linear and angular velocities, are determined using the HOSMO. Besides, the HOSMO aids in determining the unknown bounded lumped disturbances acting on the quadrotor. The output of the HOSMO is utilised for implementing the finite-time super-twisting sliding mode controller (FTSTSMC). The proposed FTSTSMC ensures finite-time convergence of tracking error with chattering attenuation. The chattering analysis for a super-twisting algorithm is presented in this work. Moreover, the overall system stability is investigated using the Lyapunov theory, and an expression for the time of convergence of the tracking and estimation error is presented. The effectiveness of the proposed methodology is established using numerical simulations and its performance is compared to a finite-time sliding mode observer coupled with a combination of proportional–integral–derivative and continuous sliding-mode controller. This is then validated in real-time using the DJI Matrice 100.

HGO-based adaptive super-twisting sliding mode power level control with prescribed performance for modular high-temperature gas-cooled reactors

This paper proposes a high-gain observer-based adaptive super-twisting sliding mode control strategy with prescribed performance (HGO-ASTSMCS-PP) for the power level of a modular high-temperature gas-cooled reactor (MHTGR). The dynamic model of the MHTGR is firstly described. By using this established model, a high-gain observer is constructed to recover the unmeasured states including relative density of delayed neutron precursor and reactor core temperature in real time. On the basis of the recovering values from the HGO, an adaptive super-twisting sliding mode control method with prescribed performance is designed. The super-twisting sliding mode control approach is adopted to improve control performance of power level for a MHTGR and suppress high-frequency chattering effects simultaneously. An adaptive mechanism is introduced to tune the control gains online so as to overcome the overestimation of the unknown disturbance boundary. In addition, by error transformation and introduction of performance function, the prescribed control performance of power level is guaranteed, which implies that the desirable convergence rate, steady power error, and maximum overshoot can be prescribed in advance. It is verified through Lyapunov stability theory that the overall closed-loop control system is globally uniformly ultimately bounded (GUUB). Finally, simulation and comparison results are presented to reveal the effectiveness of the proposed control scheme in terms of the steady and dynamic performance.

Particle swarm optimization–based adaptive super-twisting sliding mode control design for 2-degree-of-freedom helicopter

This paper presents a novel design of adaptive super-twisting sliding mode controller for two-axis helicopter with model uncertainties. The high-order super-twisting sliding mode control strategy is used to guarantee that the sliding surface can reach the equilibrium point in a shorter time and to avoid the chattering problem. The adaptive control algorithm has been developed based on Lyapunov theory to estimate the unknown parameters of 2-degree-of-freedom helicopter such that the global stability of the controlled system based on adaptive super-twisting sliding mode is guaranteed. A comparison study between conventional and adaptive super-twisting sliding mode controllers is made and the effectiveness of the proposed scheme is verified via computer simulation.

Adaptive super-twisting sliding mode control for stabilization platform of laser seeker based on extended state observer

In this paper, the stabilization platform of the seeker is analyzed to stabilize the photo-electric device by isolating the disturbances caused by vibration and turbulence from external conditions, as well as mechanical coupled torque, coiling, unbalanced torque and plant parameter uncertainty due to inner conditions. There are two important indexes to describe the performance of disturbance isolation, and these are the coupling coefficient and disturbance rejection rate. In order to improve the disturbance isolation performance of the stabilization platform of the seeker, an adaptive super-twisting sliding mode controller with an extended state observer is proposed. The adaptive super-twisting sliding mode control strategy is designed to achieve stabilized control of the stabilization platform of the seeker. The extended state observer is used to estimate and compensate for disturbances and model uncertainties. The stability analysis of the control strategy is discussed using Lyapunov stability theory. Simulation and experimental results are also presented to illustrate the effectiveness of the proposed control strategy. The proposed controller provides a better level of disturbance rejection compared to the conventional PI-DOB controller.

Design and analysis of adaptive Super-Twisting sliding mode control for a microgyroscope.

This paper proposes a novel adaptive Super-Twisting sliding mode control for a microgyroscope under unknown model uncertainties and external disturbances. In order to improve the convergence rate of reaching the sliding surface and the accuracy of regulating and trajectory tracking, a high order Super-Twisting sliding mode control strategy is employed, which not only can combine the advantages of the traditional sliding mode control with the Super-Twisting sliding mode control, but also guarantee that the designed control system can reach the sliding surface and equilibrium point in a shorter finite time from any initial state and avoid chattering problems. In consideration of unknown parameters of micro gyroscope system, an adaptive algorithm based on Lyapunov stability theory is designed to estimate the unknown parameters and angular velocity of microgyroscope. Finally, the effectiveness of the proposed scheme is demonstrated by simulation results. The comparative study between adaptive Super-Twisting sliding mode control and conventional sliding mode control demonstrate the superiority of the proposed method.

A Robust Double Closed-Loop Control Scheme for PMLSM Drives

In this paper, a novel velocity and current double closed-loop control scheme applied to the permanent magnet linear synchronous motor (PMLSM) drives is proposed, and to suppress various uncertainties and disturbances, the advanced observation technique is introduced. First, as the inner loop, the current loop adopts the predictive current control method, which can increase the current control bandwidth and tracking precision. To improve the dynamic response and robustness of the velocity loop, a super-twisting sliding-mode control strategy is presented. Second, to overcome the parameter mismatch issue in the current loop and suppress different force disturbances in the velocity loop, their respective super-twisting sliding-mode observers are structured, and the corresponding estimated values are injected into the double closed loops by the feedforward method. At last, based on the precise PMLSM testing platform, the experimental studies are carried out to prove the effectiveness and correctness of the proposed scheme.