An Approach to Improve System Performance in the Vehicle-Grid System Using Sliding Mode Control Under Multiple Operation Conditions

To address the challenges of strong electromechanical coupling, nonlinear friction, and poor disturbance rejection in semi-direct-drive scraper conveyor systems under complex coal mining conditions, this paper aims to propose a high-performance drive control strategy that balances dynamic response speed with steady-state operational smoothness. First, an integrated electromechanical coupling dynamic model incorporating Permanent Magnet Synchronous Motor (PMSM) vector control and the time-varying meshing stiffness of a two-stage planetary gear train is established. Subsequently, a Sliding Mode Control (SMC) strategy optimized with a saturation boundary layer is designed and compared with traditional Proportional-Integral (PI) control under multiple operating conditions. Time-frequency domain analysis indicates that SMC significantly enhances the dynamic stiffness of the drive system. Under sudden load change conditions, the speed recovery time is shortened by approximately 76%, and the steady-state error is reduced by 37% compared to PI control. Microscopic characteristic evaluation based on FFT and Total Variation (TV) metrics reveals that SMC achieves active disturbance rejection through spectral broadening of the electromagnetic torque. Crucially, the steady-state cumulative control effort of SMC is equivalent to that of PI, implying no additional mechanical stress burden, while the equivalent dynamic transmission force fluctuation in the mechanical chain is reduced by about 3%. The study confirms that the proposed strategy successfully achieves a synergistic optimization of “macroscopic rapid response” and “microscopic smooth operation,” providing a theoretical basis for the high-precision control of heavy-duty underground transmission equipment.

A comparative analysis of sliding mode control and PI controller for the operation of boost converter is presented in this paper. Proportional (P), Proportional Integral (PI), Proportional Integral Derivative (PID) controllers are the widespread linear control technique which are very ordinary and less costly for adjustment to a particular specification or requirement. Many industries use these controllers. On the other hand there is one non-linear sliding mode control (SMC) technique. It has many advantages like fast dynamical response, ingrained robust features of SMC. In the present paper, the boost converter is modeled and Pulse Width Modulation (PWM) based SMC and PI controllers are designed and simulated using MATLAB/SIMULINK. SMC and PI controller performance areanalyzed and compared and the results are projected.

Multiport DC-DC converters have been most commonly used in stand-alone renewable power systems to provide smooth and constant power to the loads. To supply the load without any interruption under various disturbances, the centralised controller in various typologies of multiport converter has been implemented only by using conventional proportional integral (PI) controller. This study presents the output voltage control of the three-port full-bridge converter interfacing photovoltaic (PV) system with three different controllers. The dynamic response of the proposed converter is analysed with the PI controller, fuzzy logic controller (FLC), and the sliding mode controller (SMC). The state space model of the three-port full-bridge converter is developed to analyse the performance using SMC. PI, FLC, and SMC-based control scheme is developed using the MATLAB/Simulink environment. The response of the PI, FLC, and SMC are analysed for line regulation, load voltage regulation, and for the converter parameter variation. The simulation results illustrate that the SMC gives a better steady state and dynamic response when compared with the PI and FLC. The results are presented to confirm the proposed control schemes.

For improving the robustness and control performance of permanent magnet synchronous motor control systems, a sliding mode variable structure control strategy with variable exponential reaching law is designed in this paper. The stability of the control strategy is also analyzed and proven in this paper. This method overcomes the shortcomings of PI control; it decreases the problem of severe buffeting in traditional sliding-mode variable structure controllers. Simulation and real experiments results show that the method is very effective.

Sliding Mode – PI controller is recognized as robust controller with a high stability in a wide range of operating conditions, although it suffers from chattering problem. In addition, it cannot be directly applied to multi switches power converters. This paper concerns a sliding controller design with the proportional-integral (PI) control form. First, a theoretical analysis of the considered sliding PI controller is provided. Our analysis reveals that the proportional control term of the sliding PI controller, i.e., sliding proportional controller, can reduce the chattering problem and thus, the robustness can be established. Second, the chattering problem is eliminated by smoothing the control law in a narrow boundary layer, and a pulse width modulator produces the fixed frequency switching law for the inverter. The smoothing procedure is based on limitation of pulse width modulator. Therefore, the chattering problem of the proportional gain is resolved and the valuable robust control property of the sliding integral controller is illustrated again. The simulation model has been developed and tested using MATLAB software.

In order to solve the problem of large torque and flux ripple in the traditional direct torque control of permanent magnet synchronous motor, Super-Twisting sliding mode variable structure control strategy is adopted. Under the dl coor-dinate system, the torque and flux controller is designed. In the direct torque control, the problem of speed overshoot and considerable fluctuation during PI control is adopted. The synovial speed controller is designed, and the space vector pulse width modulation technology (SVPWM) is adopted to stabilize the inverter switching frequency. The simulation results demonstrate that the method can effectively reduce the torque and flux linkage and accelerate the system response.

Recently, the low-frequency oscillation (LFO) frequently happens in the vehicle-grid system of high-speed railways when electric multiple units (EMUs) are put into operation. As a possible solution, a single-phase cascaded H-bridge static synchronous compensator (CHB-STATCOM) directly connected to the traction network is applied to dynamically compensate the reactive power of vehicle-grid system. This paper focuses on the impedance modeling and stability analysis in the vehicle-grid system with CHB-STATCOM. Firstly, the vehicle-grid system is simplified to a single-phase rectifier with large grid inductance. The accurate dq-frame impedance of the rectifier system with CHB-STATCOM is derived in detail. Secondly, through the generalized Nyquist stability criterion (GNSC), the influence of CHB-STATCOM and its different control parameters on the stability of rectifier system is revealed. Thirdly, the excellent performance of CHB-STATCOM in suppressing the LFO and the accuracy of theoretical analysis are verified via time-domain simulations. Finally, to further verify the effectiveness of CHB-STATCOM in real applications, a dSPACE based controller hardware-in-the-loop (HIL) simulation platform is established, which includes the physical control circuits of eight EMUs. The experimental results show that the CHB-STATCOM has a good dynamic compensation effect and can efficiently suppress the LFO.

Augmenting effectiveness of control loops of a PMSG (permanent magnet synchronous generator) based wind energy conversion system by a virtually adaptive PI (proportional integral) controller

In this paper, a new compound control scheme is proposed for manipulator based on radial basis function neural network (RBFNNs), sliding mode controller (SMC) and proportional–integral (PI) controller. In this control scheme, the filtered tracking error is the input of the RBFNNs update laws, SMC, and PI controller. The RBFNNs uses three-layer to approximate uncertain nonlinear manipulator dynamics. A robust sliding function is selected as a second controller to guarantee the stability and robustness under various environments. By using additional PI controllers, the goal of manipulator tuning is to minimize chattering signal, tracking performance, and overshoot can be realized. Simulation results highlight performance of the controller to compensate the approximate errors and its simpleness in the adaptive parameter tuning process. To be concluded, the controller is suitable for robust adaptive control and can be used as supplementary of traditional neural network (NN) controllers.

The positive output elementary super lift Luo (POESLL) converter is a dc–dc converter with a simple structure, which can increase input voltage with low ripples and high voltage gain. This study proposes an adaptive estimator-based sliding mode control scheme for the POSELL converter considering a reduced-order model of the converter with an unknown load and unknown input voltage. The proposed controller is composed of two parts: 1) an adaptive estimator, and 2) the sliding mode controller. At first, it is assumed that the state variables of the converter are available and adaptive estimator is proposed to facilitate the design of adaptive laws for estimating unknown parameters. Then, the sliding mode control input is designed based on the estimation of unknown parameters. Stability analysis of the proposed scheme is provided and σ-modification type robust adaptive laws for estimating the uncertain parameters are derived based on the Lyapunov direct method. Furthermore, one modification term is proposed to satisfy the sliding condition. Finally, the proposed scheme is experimentally implemented in real time using STM32F407VG discrete signal processor board interfaced with MATLAB. In addition, in order to compare and highlight the effective performance of the proposed scheme, the proportional-integral (PI) controller is designed and implemented. Experimental results are presented for both of the proposed approach and the PI one. The results verify the ability of the proposed scheme for voltage regulation as well as its robustness against parameter uncertainties. Additionally, comparison results demonstrate that the proposed controller has superior performance than the PI controller.

In recent years, energy saving and reducing CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> are requested. Therefore thermoelectric generation is noticed. Thermoelectric is a generation technology which generates electricity due to the seebeck effect when temperature difference is given to thermoelectric element. A objective of this paper is to follow electric power to reference input with operator theory and sliding mode control(SMC). Also, SMC is compared proportional-integral (PI) control on simulation. As a result, when a DC-DC converter is controlled by SMC, time to converge on reference input is shorter than when it is controlled by PI control.

The main problem of using a Proportional Integral (PI) Controller in Brushless Direct Current (BLDC) motor speed control is tuning the PI’s parameter and its performance cannot adapt to the system behavior changes. Particle Swarm Optimization (PSO) has been chosen to optimize the tuning. Fuzzy Logic Controller (FLC) is used to online tuning PI’s parameters to adapt to system conditions. Optimal adaptive PI, which combines the PSO method and FLC method to tune PI, is proposed. It was successfully implemented in the simulation environment. The test was carried out in three conditions: step responses, set-point changes, and disturbance rejection. The proposed algorithm is superior with no overshoot/undershoot. Whereas in terms of settling time is in between PI and PI-PSO. PI controller has the smallest control effort. However, the other parameter is the worst. PI-PSO is superior in terms of settling time and Integral of Absolute Error (IAE) except for the step response test. The proposed method has lower IAE and higher control effort by 78.73 % and 60 % compared to PI control. On the other hand, it has a higher IAE dan lower control effort by 11.82 % and 33.88 % compared to PI-PSO. Therefore, the optimal adaptive PI control can reduce energy consumption compared to optimal PI with better performance than PI control.

Proportional Integral (PI) controller has attracted researchers in industrial control processes because of its simplicity and robust performance in a wide range of operating conditions. It has been used to provide proportional delay differentiation on web servers in previous work. However, PI controller cannot achieve satisfactory results due to (1) the web server's non-linearity properties, and (2) the difficulty of building an accurate model for the web server. To address these issues, a nonlinear fuzzy PI controller is proposed in this paper, which has the advantage of fuzzy controller while maintaining the simplicity and robustness of PI controller. The proposed controller are self-tuned according to the periodical online performance measurement. The experimental results demonstrate that our fuzzy PI controller outperforms the PI controller in several aspects.

With the increasing number of electric multiple units (EMUs) operating in a rail depot simultaneously, low frequency oscillation (LFO) may occur. In this paper, linear active disturbance rejection control (LADRC) is designed for the single-phase EMUs rectifier control. Moreover, Nyquist criterion is adopted to analyze the stability theoretically. Furthermore, the static and dynamic performance of the system based on LADRC is verified through the resistance mutation tests in MATLAB/Simulink comparing with traditional proportional integral (PI), nonlinear PI (NPI) and auto disturbance rejection error PI (ADRE-PI). Finally, the validity of the LFO suppression with LADRC is verified in the simulation.

In this paper, an industrial grade adaptive control scheme is proposed for a micro-grid integrated dual active bridge driven battery management system (DIBMS). A benchmark industrial grade adaptive control scheme depends on two factors namely robustness and computational resource utilization when such controllers are implemented over processors. The mathematical model of DIBMS system is nonlinear, thus for desired response, non-linear controllers based on sliding mode variable structure control theory suits it well for the state regulation problem of DIBMS, however such controllers utilize high computational resources when practically implemented over processors. Keeping in view the above performance indices, this paper proposes an industrial grade computationally efficient and finite time adaptive robust convergent control for DIBMS system. A proportional integral (PI) scheme is used as central control unit and Hebbian algorithm with double integration of the state error is introduced for online tuning the gains of central control unit. The robustness and computational resource efficiency of the proposed control paradigm is validated using a laboratory scale test bench through TI Launchpad (TMS320F28379D). The superiority of the proposed AI based PI control paradigm is compared with classical PI, integer order sliding mode control (SMC), and fractional order SMC (FOSMC) in terms of computational resource utilization and robustness under all test conditions.