Simple Control Technique Research Articles

Combined simple adaptive and integral terminal sliding mode control for industrial feed drive systems

In the manufacturing industry, feed drive systems are utilized for various applications in industrial machines. These systems are crucial components for ensuring precision in motion control and are, therefore, expected to offer high tracking performance. This study focuses on application of integral terminal sliding mode control (ITSMC) to a feed drive system because of its robustness against disturbances and convergence of the tracking error in finite-time. However, its design requires plant dynamics model. To alleviate this concern, a solution of modifying the original ITSMC law to adaptive ITSMC law based on simple adaptive control (SAC) technique is used. To implement SAC-like adaptive law to a real plant, a property of “almost strictly positive real (ASPR)” is required to be satisfied. ASPR property is satisfied using velocity-based augmented output signal that ensures the stability. In experimental results, the adaptive controller follows the reference trajectory more precisely than conventional methods.

Improving Rotational Stability and Enhancing Efficiency with Variable Inertial Flywheels and Magneto-rheological Fluids

Variations in the rotational speed of a flywheel are naturally resisted by the moment of inertia. A high moment of inertia must be maintained to minimize angular velocity variations. Conversely, a significant moment of inertia makes it difficult to start spinning machines. A flywheel with a variable moment of inertia has been suggested to solve this issue. Although fluctuations between the masses' radii across the flywheel's axis may be used to approximate true inertia, the variable inertial flywheel's (VIF) control mechanisms are somewhat complex. Magneto-rheological (MR) Fluids can be utilized to avoid the complexity of the VIF. The applied device parameters determine the design and construction of the VIF system using a relatively simple control technique. To determine the relation between the semi-active VIF control system and the input parameters of a rotating electrical machine to decrease energy losses, adequate data from a VIF coupled with an induction motor (IM) system is gathered in this study. An analysis was done on the system, and the outcome showed a possible improvement in the performance of IM. This study significantly reduces power consumption and smooth speed build-up possibility for the proposed system.

Improvised direct torque control of a permanent magnet synchronous motor

Permanent magnet synchronous motor (PMSM) is widely used in different applications because of their different key operation features. But despite having important key features, PMSM suffers from torque ripple when simple control techniques like direct torque control (DTC) are employed. Several approaches have been raised by many researchers to lessen the ripple when DTC is used for controlling the PMSM drive. In this work, duty ratio-optimized DTC control, which has the same simplicity as conventional DTC (CDTC), and delay compensation for input signal prediction are proposed. In the proposed system, to determine the duty ratio, slope manipulation was made by considering the minimization of torque error and forcing the developed torque to be equal to the reference torque at the end of the span. An online slope determination approach was employed to compute the duty ratio. MATLAB 2021b is used for simulation purposes. The dynamics and steady-state performance of the proposed scheme were tested for both variable-load and variable-speed operations. In addition, the harmonic performance and ratio of harmonic power loss to total active power loss of the motor were evaluated. In general, the proposed scheme performs effectively in reducing steady-state ripple and harmonic.

Real-Time Implementation for the Robust Controller of the Switched Boost Inverter within an Autonomous Modified Nanogrid

SBI stands for switched-boost inverter and is a single-stage power converter used to connect low-power sources, such as solar photovoltaic (PV) arrays within a modified nanogrid, to loads. Despite its many benefits, such as the fact that it does not require expensive sophisticated dead-time circuitry, its duty ratio is limited to between 0 and 0.5. As a result, this publication is a contribution towards improving the SBI's performance for use in a modified nanogrid. Furthermore, it also presents a revolutionary strategy for a simple closed-loop control technique that overcomes the majority of inverter shortcomings and system nonlinearity. The suggested robust controller uses a metaheuristic optimization technique, called gorilla troops optimization (GTO), to optimize the performance of this controller. The robustness of the suggested controller is tested against the sudden change of the nanogrid input voltage (i.e., PV-voltage), modulation index of the inverter, and the step-change in DC-link output voltage of the inverter. The test results obtained from Matlab/Simulink software are compared with particle swarm optimization (PSO) – as another optimization algorithm. Furthermore, the proposed system is experimentally implemented with OPAL RT-4510v real-time hardware in the loop (HIL), rapid control prototyping, OP-8660 HIL controller and data acquisition platform.

Augmented dynamics of nonlinear systems: A review

We discuss a simple yet powerful control technique called “Linear Augmentation” (LA) for nonlinear dynamical systems. The linear augmentation can be perceived as a type of interaction that may occur naturally in dynamical systems as an environmental effect, or can be explicitly added to a system in order to control its collective dynamical behavior. LA has been known to effectively regulate resulting dynamics of various dynamical systems and can be used as a powerful control strategy in various applications. Examples include targeting attractor(s), regulating multistable dynamics, suppression of extreme events, and controlling chimera states in the nonlinear dynamical systems.

Converter Control During Low Voltage Ride Through Operation for Grid-Interfaced Solar PV Battery Assisted System

The grid interfaced solar PV based distributed generation system (DGS) installations have increased tremendously. The penetration of DGS into the grid requires the DGS converter to pose the fault ride through capability. It demands the converter to remain connected during sags and to provide reactive power support to the grid. In this work, the grid interfaced solar PV-battery assisted system for balanced as well as unbalanced power generation along with low voltage ride through (LVRT) functioning is presented. An efficient and simple control technique is developed for the system, such that the DGS converter stays connected to the grid under fault conditions till the LVRT required standards are fulfilled. The DC link voltage variations and LVRT control are achieved by the battery energy storage (BES) bidirectional DC-DC converter (BDDC). The positive sequence grid current components are considered to meet the LVRT standards. The controller ensures the DGS converter currents are within the rated limits. The presented control strategy of DGS converter operation during voltage sags and unbalanced power generation is simulated and validated in MATLAB/Simulink. The developed topology and its control are validated through test results.

A simple duty cycle control technique to minimize torque ripple in open-end winding induction motor

Modern electric vehicles (EVs) that drive an induction motor (IM) fed by a traction inverter are fast gaining popularity due to their simple configuration and robustness. The direct torque control (DTC) technique is one of the best control methods to drive the IM, especially in open-end winding configurations, as it offers more voltage vectors. However, the existence of hysteresis controllers and improper switching technique causes larger torque ripples that leads to variable switching frequency. The study will be focused on the open-end winding induction motor where the direct current (DC) power is fed from both sides of the stator windings using the dual inverter configuration. To minimize the torque ripples, a simple switching technique using the duty cycle control method is proposed by injecting a high-frequency square wave into the default inverter switching status to form the new pattern of voltage vectors. The effectiveness of the proposed technique is tested through MATLAB/Simulink software and validated experimentally with a lab-scale setup using a dSPACE controller. The findings show that the proposed method reduces torque ripple by over 50% while keeping the DTC's simple structure.

Experimental rotation control of the parametric pendulum using a velocity approach

This paper addresses the application of a simple control technique for reaching a stable rotational motion of the parametrically driven pendulum, starting from non-rotating responses. The control action consists of an assistance torque, which is provided conveniently to a pendulum wheel in order to increase its angular velocity. The magnitude of this torque is defined as inversely proportional to the magnitude of the angular velocity of the pendulum, which is computed in real time from angular position measurements. Maximum torque is applied when velocity is zero, while decreasing linearly as velocity increases. The assistance torque takes a very low value when the magnitude of the velocity reaches a threshold, which is defined in terms of the dynamics of the unforced pendulum. The direction of torque application depends on the sign of the angular velocity. The experiments show that rotations can be reached and maintained by means of this technique under a simple harmonic forcing and under an irregular forcing. Besides, since the control law is not dependent on the forcing period, it is intuited that it has the potential to produce good results under pseudo-stochastic forcing. This is of particular importance, with a view to a possible use in ocean wave energy converters, which is nowadays a promising engineering application of parametric pendulum systems. This is in line with the main motivation of this work, which is the implementation of this control technique to maintain the rotational motion of a pendulum-based wave energy converter.

Enhanced Motion Accuracy in Industrial Feed Drive Systems Using Simple Adaptive Control with a Jerk-Based Augmented Signal

In precision motion technology, motion accuracy is crucial to eliminate potential effects of screw compliance and improve the performance of feed drive systems. This study focuses on motion accuracy improvement for feed drive systems using simple adaptive control (SAC) technique. Almost strictly positive real (ASPR) is a key property to implement SAC to a system. The jerk-based augmented output signal is proposed for the ASPR property that includes velocity, acceleration, and jerk signals. The proposed approach allows the controller to achieve high tracking accuracy and faster adaptation by placing zeros of the controlled system at appropriate locations. To verify the feasibility of the proposed approach, control simulations are conducted and the results are compared with a typical parallel feedforward compensation method. Simulation results revealed that the proposed approach reduces tracking error significantly.

H-Infinity Electronic Controller Fails for Integrated Delay in Aircrafts

When the time delay is integrated into the dynamic system definition and the analysis of a complex dynamic system such as aircraft is carried out, it depicts that integrating the delay into the definition would be advantageous in evaluating the performance of the aircraft at a faster rate. It also stabilizes the plant at a faster rate when compared to classical control techniques applied on systems considering delay as a separate entity. An H-infinity controller is designed for the integrated system and analyzed as part of the studies that yielded interesting observations on the H-infinity limitations. The analysis of the system when compared to simple classical control techniques is vividly advantageous however when delays are integrated and critical delay impacts are not calculated, the chances for failure of a dynamic system control predominantly increase owing to varied complex governing equations which otherwise would be approximated with linear models.

Third Order Converters with Current Output for Driving LEDs

Light emitting diodes LEDs are highly efficient in changing electrical energy into light. The applications are lightning, but also medical treatments, and disinfection. After a short discussion of the simplest converter which is based on the Buck converter several third order current converters, which are suitable to drive an LED load, are treated. The Buck converter with input filter, the output current Boost converter, and the output current Cuk converter are shortly treated, but for the other topologies simple control techniques are given. These converters are the current output converter based on the Zeta converter, two converters with a quadratic term of the duty cycle in the voltage transformation ratio, the quadratic step-down converter with current output and the D square divided by one minus d current output converter, which is a step-up-down converter, and two converters which function only for a limited duty cycle, the (2d-1)/d step-down and the (2d- 1)/(1-d) step-up-down output current converters. The dynamics of example converters is shown with the help of LTSpice simulations.

Generalization of Reset Controllers to Fractional Orders

Reset control is a simple non-linear control technique that can help overcome the structural limitations of linear control. Fractional control uses the concept of fractional derivatives to expand the range of possibilities when modeling a controller, making it more robust. Fractional reset control merges the advantages of both areas and is the object of this paper. Fractional-order versions of different reset controllers were implemented, namely a fractional Clegg integrator, a fractional generalized first-order reset element, a fractional generalized second-order reset element, and fractional “constant in gain lead in phase” controllers with first- and second-order reset elements. These were computed directly from a numerical implementation of the Grünwald–Letnikov definition of fractional derivatives, and their performances were analyzed.

Synthesis and Implementation of a Multiport Dual Input-Dual Output Converter for Electric Vehicle Applications

In recent years, multiport DC-DC converters are seen in a variety of power converter applications in electric vehicles. The design of multiport converter architectures plays a major role in DC microgrids and electric vehicle applications. This research examines a modified multiport converter structure interface with dual inputs and dual outputs used in electric vehicles. The versatility of accommodating energy sources with varying voltage and current nature characteristics is the most notable feature of this converter. During operation, the proposed architecture can offer a boost as well as buck operations at the same time. The suggested dual input-dual output (DIDO) converter is built with fewer components and a simpler control technique which makes it more dependable and the converter is cost-effective. Furthermore, this structure allows the power to flow in both directions making it to be utilized in electric vehicle battery charging during regenerative braking. The converter’s steady-state and dynamic behavior are investigated, and a control strategy for regulating the power flow among the varied input energies is proposed. To develop the suggested converter, a small-signal model is modeled. MATLAB simulation and experimental findings are used for the verification of converter design and validated the performance behavior experimentally using a hardware setup.

Transient Stability Analysis of a Multi-Machine Power System Integrated with Renewables

The impact on the stability of power systems is rising as the penetration level of renewable energy with sporadic natures rises rapidly on the grid. However, the impact of different types of renewable energy sources (wind, solar) and their combination on system stability varies even with the same penetration level. This paper concentrates mainly on the stability analysis of multi-machine systems connected to various types of renewable energy sources. The study presents a simple and novel control technique named automatic reactive power support (ARS) for both single and combinations of renewable sources by injecting the available reactive power into the system during fault through converters to enhance system stability. The permanent magnet synchronous generator (PMSG) and doubly fed induction generator (DFIG) are both considered as wind generators in this paper for comparison. In addition, transient stability enhancement is carried out by improving critical clearing time of a three-phase fault in the power system. With the creation of a 3-phase fault at various buses, stability analysis is carried out on the 9-bus WSCC test bus system and also on the 68-bus IEEE test system. Comparative analysis of six test case conditions is provided and the considered cases are without renewable source, with DFIG as a wind generator, PMSG as a wind generator, solar PV farm, wind farm with DFIG and solar PV in combination and the combination of wind farm with PMSG and solar PV. Moreover, the improvement in critical clearing time of the system is compared using conventional and proposed controls with all the aforementioned renewable sources. Comparative results show that the proposed control technique improves system stability and also that the combination of renewable energy sources ought to enhance the critical clearing time of system.

Hardware Design of Low Cost Myoelectric Controlled Prosthetic Hand For Engineering Laboratory

This study presents a low cost, two-channel, on-off type, constant speed myo-electric controlled prosthetic hand project as an educational tool for Biomedical/Control/Mechatronic Engineering. Surface Electromyogram (sEMG) signals were recorded from the muscles of flexor carpi ulnaris and extensor digitorium on the forearm. Signal conditioning of these signals is performed in the analog stages of the system, before passing it on to a microcontroller for further filtering and implementation of control. The control logic is simplified to represent the muscles as being active or inactive, resulting in a very simple on/off control based on the two signals. The on/off control signals are used to drive a myo-electric controlled prosthetic hand-powered by a hobby RC servo motor. A printed circuit board has been designed for the analog stages of the system, and a simple Arduino Microcontroller is used for the digital stages. Other commercial off-the-shelf components were used to keep the cost of the hardware and the software components as low as possible. This project was used as a teaching aid for the final year undergraduate students to demonstrate the use of simple myo-electric signal processing and control techniques.

Gesture Controlled Robot with Robotic Arm

Abstract: In today's world, industry and daily routine tasks are increasingly attracted to and implemented through robotic automation. Well, this study proposes a method for replacing buttons and joysticks with a more novel technology, namely, commanding the entire Robotic Arm with the user's hand movement, motion, or gesture. The goal is to alter how people think about remote controllers for manually driven robotic arms. Pick and place robots are a type of technology used in the industrial industry to execute pick and place tasks. The system is constructed in such a way that it reduces human error and intervention, resulting in more exact work. The system is designed with a simple, flexible, and minimum control technique in mind. There are numerous domains in which human intervention is problematic, yet the process in question must be operated and regulated, which leads to the application of robots. According to the literature, pick and place robots are conceived and deployed in a variety of industries, including the bottle filling industry, surveillance to identify and eliminate bombs, and so on. The goal of the project is to create a gesture-controlled robot with a robotic arm that can perform any pick-and-place tasks. A radio frequency transmission is used to control the pick and place robot. For the gripper open and close, up and down, forward and backward, base clockwise and counterclockwise, the Robotic Hand has certain independent commands. Four Omni wheels support the robotic arm's displacement on the chassis. The implemented robotic arm has four degrees of freedom. Line follower, wall hugger, obstacle avoider, metal detector, and other capabilities can be added to this robot to increase its versatility. Index Terms: Pick & Place Robot, Robotic arm, Robotic Hand.

SCHEMING OF CONTROLLER FOR SINGLE STAGE SOLAR PV FED BLDC MOTOR-DRIVEN WATER PUMP

To optimize the solar photovoltaic (PV) generated power using a maximum power point tracking (MPPT) technique, a DC-DC conversion stage is usually required in solar PV-fed water pumping which is driven by a brushless DC (BLDC) motor. This power reformation stage leads to an increased cost, size, difficulty, and decreased efficiency. As a unique solution, this work addresses a single-stage solar PV energy conversion system feeding a BLDC motor pump, which eliminates the DC-DC conversion stage. A simple control technique capable of operating the solar PV array at its peak power using a common voltage source inverter (VSI), is proposed for BLDC motor control. The proposed control eliminates the BLDC motor phase current sensors. No supplementary control is associated with the speed control of the motor pump and its soft start. The speed is controlled through the optimum power of the solar PV array. The suitability of the proposed system is exhibited through its performance evaluation using MATLAB/Simulink-based simulated results. keywords: MPPT, solar PV array, BLDC motor, Water pump, Voltage source inverter (VSI)

Numerical Study on Rod Thrust Vector Control for Physical Applications

Mechanical thrust vector control is a classical and significant branch in the thrust vector control field, offering an extremely reliable control effect. In this article, steady-state and unsteady-state aerodynamic characteristics of the rod thrust vector control technology are numerically investigated in a two-dimensional supersonic nozzle. Complex flow phenomena caused by the penetrating rod in the diverging part of the supersonic nozzle are elucidated with the purpose of a profound understanding of this simple flow control technique for physical applications. Published experimental data are used to validate the dependability of current computational fluid dynamics results. A grid sensitivity study is carried through and analyzed. The result section discusses the impacts of two important factors on steady-state aerodynamic features, involving the rod penetration height and the rod location. Furthermore, unsteady-state flow features are analyzed under various rod penetration heights for the first time. Significant vectoring performance variations and flow topology descriptions are illuminated in full detail. While the rod penetration height increases, the vectoring angle increases, whereas the thrust coefficient decreases. As the rod location moves downstream close to the nozzle exit, the vectoring angle and thrust coefficient increase. In terms of unsteady-state aerodynamic effects, certain pressure oscillations occur upstream of the rod, which resulted from the expanding and shrinking of the upstream anticlockwise separation bubbles.

Investigation of Adaptive Droop Control Applied to Low-Voltage DC Microgrid

In a DC microgrid, droop control is the most common and widely used strategy for managing the power flow from sources to loads. Conventional droop control has some limitations such as poor voltage regulation and improper load sharing between converters during unequal source voltages, different cable resistances, and load variations. This paper addressed the limitations of conventional droop control by proposing a simple adaptive droop control technique. The proposed adaptive droop control method was designed based on mathematical calculations, adjusting the droop parameters accordingly. The primary objective of the proposed adaptive droop controller was to improve the performance of the low-voltage DC microgrid by maintaining proper load sharing, reduced circulating current, and better voltage regulation. The effectiveness of the proposed methodology was verified by conducting simulation and experimental studies.

A future concern of iterative learning control : A survey

The main idea of iterative learning control (ILC) was exposed when Arimoto’s first paper was published. Industrial tasks mainly in repetition are controlled by an iterative teaching controller in both iteration and time-domain which makes ILC unique. ILC is becoming very popular among control engineers because of its very simple and effective control techniques. This paper describes the basic key knowledge about ILC and its types of applications. The core concern of this paper is to elaborate and explore the future scope and key application areas of iterative learning control in engineering as well as other all subjects of interest.