KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Search Results

Now showing 1 - 8 of 8

Some of the metrics are blocked by your
consent settings
Constrained Nonlinear Control of Semi-Active Hydro-Pneumatic Suspension System
(2025-09-01)
Qiu, Biao
;
Jettanasen, Chaiyan
Aiming at the characteristics of limited actuation capability of the semi-active control system and strong nonlinearity of the hydro-pneumatic suspension, a constrained nonlinear control strategy of a semi-active hydro-pneumatic suspension system is proposed. According to the mathematical model of nonlinear hydro-pneumatic suspension, the static stiffness and linear damping coefficient based on the equivalent energy are calculated, and then the control-oriented dynamic equation whose expression minimizes the nonlinear term is constructed. Combined with actuation capacity constraints, an optimization model with constraints is established to minimize the deviation between the actual overall control force and the expected optimal control force, and the optimal approximation from nonlinear control to linear quadratic optimal control is realized. The control simulation results of various methods show that the nonlinear control with constraints of the semi-active hydro-pneumatic suspension system, which effectively combines the actuation capacity constraints and nonlinear characteristics of the system, achieves a good comprehensive control effect for the nonlinear suspension control with constraints.
Some of the metrics are blocked by your
consent settings
Robust fixed-time control for DC-DC converter with matched and mismatched perturbations
(2025-08-01)
Cholahan, Varin
;
Tangsrirat, Worapong
This paper introduces a state-dependent variable exponent coefficient for fixed-time sliding mode control. The proposed state-dependent sliding surface ensures system stability and facilitates a rapid response within a fixed timeframe, while also addressing both matched and mismatched perturbations. This sliding mode control is applied to the DC-DC converter, a system that frequently encounters mismatched issues. By using the fixed-time concept, the designed sliding mode surface exhibits robustness, enabling it to manage both matched and mismatched perturbations within a fixed-time duration. We first present the average mathematical model for the continuous mode DC-DC converter. Next, a state-dependent sliding surface with a variable exponent coefficient is developed. Following next, the controller is designed to regulate the converter's voltage while effectively rejecting both matched and mismatched disturbances. The stability of the proposed approach is evaluated through the use of a Lyapunov function. Lastly, numerical simulations demonstrate rapid convergence and significant robustness against uncertainties in parameters, both matched and mismatched. When compared to other fixed-time and finite-time schemes, the proposed fixed-time controller is notable for its high efficiency and relatively straightforward control solution.
Some of the metrics are blocked by your
consent settings
FINITE-TIME NONLINEAR SPEED CONTROLLER OF PERMANENT MAGNET SYNCHRONOUS MOTOR USING C MEX S-FUNCTION
(2025-07-31)
Cholahan, Varin
;
Rattanakun, Kritsana
;
Tangsrirat, Worapong
Permanent magnet synchronous motor (PMSM) has high torque and possesses a simple structure relative to its capacity. It has been popularly applied in numerous industrial applications. Nonetheless, PMSM is sensitive to both internal and external disturbances. It exhibits significant nonlinearity and functions as a multi-variable coupling system. Therefore, a control system capable of delivering superior performance must be nonlinear. Owing to its considerable robustness capability, the sliding-mode control (SMC) technique is extensively utilized in this research. This work also demonstrates the use of C Mex S-function, the most efficient code-oriented tool, to simulate the operation of nonlinear systems. The C-Mex S-function is an effective and practical approach for developing models within the SIMULINK/MATLAB user interface environment and utilizing its requisite capabilities. Consequently, the nonlinear controller established in this study is carried out via the C-Mex S-function. Let’s manipulate the characteristics of the PMSM to converge to equilibrium within a finite time period. The tracking speed signal can be quickly followed with a high robustness against disturbances, uncertainties, and unmodeled variables. In addition, the Lyapunov function is employed to assess the stability of the developed SMC controllers, whereby the stable convergence property is demonstrated and proven. To illustrate the performance of the continuous fast-terminal sliding-mode control scheme, some simulation tests are performed on the speed regulation of the PMSM drive plant. The simulations are presented as code resembling the C programming language within SIMULINK/MATLAB. The findings show that the proposed controller achieves a speed overshoot of less than 3%, a settling time of approximately 0.15 seconds, and a steady-state error of less than 0.5 rad/s under a load torque of 1.5 Nm. These results highlight the high performance and robustness of the proposed speed controller.
Some of the metrics are blocked by your
consent settings
Observer-less Fixed-Time Speed Control For Permanent Magnet Synchronous Motors with matched-mismatched disturbances
(2025-01-01)
Cholahan, Varin
;
Wongvanich, Napasool
;
Tangsrirat, Worapong
This paper presents a state-dependent Variable Exponent Coefficient Sliding Mode Control (VECFSMC) By inducing fixed-time stability analysis, the proposed state-dependent sliding surface provides not only system stability but also a quick response in a fixed period of time as well as counteract with matched and mismatched disturbances. The proposed sliding mode control strategy does not use observers to estimate the disturbances. The designed sliding mode surface possesses robustness properties which is sufficient to cope with both matched and mismatch disturbances in a period of fixed time. Firstly, the mathematical model of permanent magnet synchronous motor and the mathematical background of variable exponent coefficient are demonstrated theoretically. Secondly, the state-dependent sliding surface with variable exponent coefficient is designed. The controller that can manipulate both the speed of PMSM and matched-mismatched disturbances is constructed. Lyapunov function is applied to assess the stability of the proposed method. Finally, a numerical simulation with PMSM drive shows fast convergence, good robustness against both matched and mismatched disturbances. The proposed fixed-time controller with this observer-less method offers high efficiency and offers not too complicated control solution comparing to the other fixed-time and finite-time methods with a small number of parameters.
Some of the metrics are blocked by your
consent settings
A Novel Practical Fixed-Time Speed Control of Permanent Magnet Synchronous Motors with Input Saturation
(2025-01-01)
Cholahan, Varin
;
Wongvanich, Napasool
;
Tangsrirat, Worapong
In this article, we focus on a control problem for the speed control of a permanent magnet synchronous motor (PMSM). An antisaturation adaptive fixed-time nonsingular sliding mode control (AFFTNSM) with disturbance estimation compensation is designed for a class of second-order nonlinear systems to improve PMSM system performance. Firstly, a novel fast fixed-time nonsingular sliding mode surface is chosen based on the error dynamic equation. Then, a practical fixed-time sliding mode control algorithm is proposed where the stability of the proposed controller is demonstrated to show the convergence of the velocity tracking error to a neighborhood of the origin in fixed-time. The implementation of feedforward compensation of disturbance enhances the dynamic performance of the fast fixed-time nonsingular sliding mode control rule, resulting in reduced chattering phenomena. Numerical simulation results are provided to verify the efficiency of the proposed method.
Some of the metrics are blocked by your
consent settings
Robust Practical Fixed-Time Control and Application to DC-DC Buck Converter
(2024-01-01)
Wongvanich, Napasool
;
Cholahan, Varin
;
Tangsrirat, Worapong
This work presents an adaptive fixed-time speed controller of permanent magnet synchronous motors for a class of second-order nonlinear systems based on practical fixed-time stability, in which a sliding mode surface with a constant exponent coefficient is designed to avoid singularities and achieve a fast convergence rate. This method is easy to implement compared to other sophisticated fixed-time controllers. In addition, the upper bound of control inputs is selected to prevent saturation limitations. Following that, the Lyapunov function expresses the close-loop stability of a practical fixed-time controller. An adaptive disturbance rejection with smooth function is presented to attenuate the total disturbances, chattering, and steady-state error. The tracking error is integrated into a bounded residual region within a specified time. Finally, numerical simulations are given to verify the performance of both controller and disturbance rejection mechanisms.
Some of the metrics are blocked by your
consent settings
On practical control of electronic throttle body
(2012-12-01)
Jansri, Anurak
;
Pongsuttiyakorn, Thadchapong
;
Sooraksa, Pitikhate
An electronic throttle body is a nonlinear device that includes effects on dead time, transmission friction, throttle plate friction and return spring limp-home. The effects are problem to precisely control of electronic throttle regulation. In recent year, various control designs have been proposed. This paper presents a simple yet effective nonlinear controller to enhance the regulator. The regulator is embedded using a discrete fuzzy PI algorithm, provided easy tuning, robustness and rapid development with simple architecture. The effects are also in consideration. The experiment results are carried out and show satisfactory performance using standard criteria such as an integral of absolute error (ITAE), an integral of square error (ISE) and a mean absolute error (MAE). © 2012 IEEE.
Some of the metrics are blocked by your
consent settings
Simple nonlinear air to fuel ratio control for spark ignition engines
(2012-07-30)
Jansri, Anurak
;
Sooraksa, Pitikhate
Development of a mathematical model of air to fuel ratio and control for SI engines has been proposed in various themes to satisfy technical specification. This paper reveals a simple yet effective nonlinear control to enhance the regulator. The mean value engine model (MVEM) is employed and enhanced to validate the effectiveness of the proposed scheme. The regulator is designed using a discrete fuzzy PI algorithm, provided easy tuning, robustness, and rapid development with simple architecture. Effects on dead time, exhausted delay, and chaotic disturbance are also included. The simulation results show satisfactory performance using standard criteria such as an integral of absolute error (ITAE), an integral of square error (ISE) and an integral of absolute control output (IACO) and a mean absolute error (MAE). © 2012 IEEE.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results