PID Regulator Research Articles

The use of the localization method for calculation of the robust PID regulator parameters for unmanned aircraft servo motor

The problem of controlling a typical nonlinear servo motor of an unmanned aercraft with non-stationary parameters using a robust PID controller is considered. The procedure for calculating the parameters of a robust PID controller based on the localization method (further - LM PID controller) for continuous and discrete control systems is studied. The influence of disturbing factors (internal and external) acting on the servo motor is considered. It is established that the main perturbations acting on the servo drive include internal perturbations, which are changes in the time constant and its gain from the temperature of the environment and the quality of the supply voltage. The simulation in the class of linear and nonlinear continuous systems showed that a servo drive with a ML PID controller has the property of robustness in the working range of changes in both the input signal and the parameters of the servo drive and controller. Simulation results showing the research are presented. When describing a servo motor with an LM PID controller in the class of linear discrete systems, its robustness is limited by a narrow range of variation of both its parameters and the quantization period of the input signal. As the degree of uncertainty in the parameters of the servo motor increases (approaching the working range of their change), the discrete system loses stability. For the synthesis of robust control circuits of an unmanned aercraft with given characteristics, mathematical dependences of the settling time and static error of a typical servo motor with LM PID controller from the quantization period of the input signal and the degree of uncertainty in its parameters are presented.

Dynamic modeling and control of five phase SVPWM inverter fed induction motor drive with intelligent speed controller

Multi-phase induction motor (IM) drive is an emerging field of electric drive applications. This enables us to use the multi-phase AC machine than a three-phase machine. Precision speed control is important for industrial applications. Hence, direct torque control (DTC) with PI or PID regulators used, and these regulators are not flexible because of a constant gain in all working conditions. Therefore, robust speed control is essential for the precision speed control in industrial applications. The major objective of this study is to investigate a novel speed control for DTC of 5-ϕ VSI with space vector PWM (SVPWM) technique fed IM drive using wavelet fuzzy logic interface system. In precise, wavelet-fuzzy controller is an alternative for the PID controller used for DTC IM drive. The speed error signal comprises many short and extraordinary-frequency components. The scaled gains are generated for a DTC IM drive by the decomposition of discrete wavelet transform and the fuzzy logic controller (FLC) from high and low-frequency signals. The investigation of 2 hp 5-ϕ VSI fed IMD is carried out using the simulation model developed in MATLAB2016a software and examined under various working conditions. The simulation results are shown in this paper to confirm the suitability for industrial applications.

Active Control Method for Torsional Vibration of DFIG Drive Chain Under Asymmetric Power Grid Fault

When the asymmetric fault occurs in power grid, it will cause the oscillation of the electromagnetic torque of the doubly-fed induction generator(DFIG). The oscillation of the electromagnetic torque will cause the torsional vibration of the drive chain, and the long-term torsional vibration will shorten the service life of DFIG. The analysis shows that the positive and negative sequence current components generated by DFIG terminals are the main factors that cause electromagnetic torque oscillation when the asymmetric faults occur. Therefore, the suppression of positive and negative sequence current components is the key to achieve active control of torsional vibration of drive chain, the traditional PID control can only adjust the direct-current(DC) component without static error, and cannot suppress the negative sequence alternating-current(AC) component. In this paper, based on the traditional PID regulator, the resonance(R) current regulator with the specific frequency is incorporated into the grid-side converter(GSC) to form the PID-R current controller. The PID-R current controller can realize accurate and effective control of the positive and negative sequence components in the forward rotation synchronous speed rotating coordinate system without decomposing the positive and negative sequence components, and can actively suppress the electromagnetic torque oscillation, thereby realize the active control of the drive chain torsional vibration. MATLAB/Simulink verifies the effectiveness of PID-R current controller.

Fractional Order PID Controller for DC Link Voltage Regulation in Hybrid System Including Wind Turbine- and Battery Packs- Experimental Validation

This paper presents a fractional order PID (FOPID) to control the operation of a stand-alone hybrid energy system with a wind turbine based on permanent magnet synchronous generator (PMSG) and a battery bank. In order to maintain the DC-link voltage at its reference value, regardless the variation in wind speed and load impedance a FOPID controller using a DC-DC buck-boost converter fed by a lead acid battery bank is used. The line to line AC output voltage regulation based on PID controller to supply RL load with constant amplitude and frequency has been achieved. The proposed FOPID controller is examined through simulation using MATLAB-simulink and experimentally via an experimental test bench under step change variation of wind speed and load impedance. The obtained simulation and experimental results using FOPID controller show better performances than the conventional PID regulator in terms of less settling time and lower overshoot in the transient state as well as a minimum steady state oscillation.

Dual Quaternion Delay Compensating Maneuver Regulation for Fully Actuated UAVs

Abstract In aerial robotics, path following constitutes a popular task requiring a vehicle to pursue a given trajectory. Resting upon the fulfillment of a desired time law, trajectory tracking techniques often turn out to be ineffective in presence of external disturbances, favoring the adoption of maneuver regulation strategies wherein the desired trajectory is parameterized in terms of the path-variable. In this scenario, this work proposes a new delay-compensating maneuver regulation controller for fully actuated aerial vehicles, whose aim is to guarantee the perfect tracking of a given path in the shortest time interval. The innovative aspect of such a solution relies on the introduction of a recovery term that compensates for possible delays in the task execution. The dual-quaternion formalism is adopted to model the dynamics of the aerial platforms allowing feedback linearization of the whole system, including both position and attitude, with a single controller. The tests conducted in Gazebo physics simulator show that the proposed controller outperforms the popular trajectory tracking PID regulators.

Interactive Software Tool for Design of Higher Derivative Degree PID Controllers

A new class recently developed controllers extends the family of PID regulators by several new features. The aim of this contribution is to present an interactive software tool for computer support of these controllers among researchers, students and broader research community by providing them with a graphical interface enabling to interact with the controllers and choose their tuning that best fulfils specified requirements. The main advantage of the new controllers, which cover the gap between traditional and fractional-order PID controllers, is that the more consistent solution to the noise filtering problem makes possible work with higher order derivatives and achieving broader spectrum of performance specifications. The paper briefly summarizes in a general way the design of PID controllers with higher derivative degree, noise attenuation and compensation of time delays. Based on this summary and further references the developed software tool is being described that takes the form of a virtual laboratory. The back-end of the tool relies on Matlab simulations, when it provides data of setpoint and disturbance step responses in the chosen loop, where the controlled system is represented by the first order time-delayed system distorted by a noise. The output data of Matlab simulations are processed with the front-end part of the software tool that uses possibilities of JavaScript programming language to interact with the control system and graphically visualize the results in different views within the Web browser environment.

Research and Application of Self-tuning PID Regulator

In industrial production, the application of PID regulators is becoming more widespread. Among them, the self-tuning PID regulator is used by many products in the production process because of its unique advantages. The self-tuning PID regulator refers to a controller that includes a parameter self-tuning of a proportional control module, an integral control module, and a differential control module. The proportional control unit is used to generate a stable error, the integral control unit is used to eliminate the error signal, and the differential control unit is used to handle the effects of the hysteresis component. The parameters of the PID regulator for parameter setting mainly include the Z2N method, the 4:1 attenuation method and the critical proportional method. The steps of PID parameter tuning include adjusting the proportional gain, integral time constant, differential time constant, and parameter trimming. It is necessary to adjust the parameters from the aspects of speed, efficiency, stability, etc., so that the parameters complement each other and continuously improve the overall performance of the system.

Design of torque system for electric bicycle based on fuzzy PID

This article analyses the structure and working principle of the brushless DC motor, the advantages and disadvantages of PID regulation and fuzzy control are analysed as well, and puts forward the fuzzy PID motor control technology with both advantages. The speed control of the brushless DC motor is carried out and the simulation model is built. The results show that, compared with the traditional PID adjustment, the fuzzy PID makes the motor speed more stable and the speed fluctuation decreases obviously, which satisfies the requirement of the speed control of the electric bicycle.

Evaluation of Mössbauer spectra linearization methods

Mossbauer spectra linearity is a critical parameter for Mossbauer spectrometer accuracy determination. This paper deals with comparison of various Mossbauer spectra linearizing methods. First method uses sine velocity waveform followed by linearization process. Next method introduces additional modulation based on the velocity error signal measured by laser vibrometer. Last evaluated method combines both. It uses the velocity error signal measured by laser vibrometer as linearization function. Custom Mossbauer spectrometer was constructed for the linearization evaluation. The spectrometer velocity driving system is based on the digital PID controller concept deployed in the FPGA chip of CompactRIO real-time hardware device. The obtained data demonstrate that all evaluated methods increases the linearity of spectra in a wider frequency and amplitude range of a drive signal in comparison with those measured using a traditional measurement method. Highest linearization effect has the method using sine velocity waveform, as generally harmonic movement is natural for used double loudspeaker type velocity transducers. Results show the possibility to use proposed linearization methods for higher velocity ranges using standard transducers and shows potential to be applied in the simple control of transducers without PID regulation or in piezoelectric transducer applications.

Modeling of the Controlled Air Spring

Abstract The pneumatic springs are frequently used as a machine component. They are mainly used for passive vibration damping with the possibility to regulate the working height of the springs. The paper describes the creation of a mathematical model of a spring controlled thru the PID regulator. At conclusion are summarized the limits of PID control and sketches the future possibility of substituting the PID controller by a neural network.

An ANN-Based Temperature Controller for a Plastic Injection Moulding System

This paper proposes an approach to an ANN-based temperature controller design for a plastic injection moulding system. This design approach is applied to the development of a controller based on a combination of a classical ANN and integrator. The controller provides a fast temperature response and zero steady-state error for three typical heaters (bar, nozzle, and cartridge) for a plastic moulding system. The simulation results in Matlab Simulink software and in comparison to an industrial PID regulator have shown the advantages of the controller, such as significantly less overshoot and faster transient (compared to PID with autotuning) for all examined heaters. In order to verify the proposed approach, the designed ANN controller was implemented and tested using an experimental setup based on an STM32 board.

A novel MPPT technique to increase accuracy in photovoltaic systems under variable atmospheric conditions using Fuzzy Gain scheduling

ABSTRACT Photovoltaic (PV) system has gradually become a research focus in the field of renewable energy power generation, and the output efficiency of PV system is the major concern of researchers. There are obvious non-linear characteristics in the output of PV system, and it will be greatly affected by the external environment. For achieving the maximum output power, PV system must operate under the guidance of maximum power point tracking (MPPT) methods. The tracking time and accuracy of these methods need to be improved. Therefore, this study contributes to increasing the output efficiency of PV system by improving the tracking time and accuracy with using Fuzzy Gain Scheduling of Proportional-Integral-Derivative (FGS-PID) regulator in the grid-connected mode. The suggested adaptive FGS-PID scheme is implemented using two-level control system architecture, combining the benefits of fuzzy logic as well as conventional PID regulator. Ziegler–Nichols tuning method is employed to select the initial values of PID gains. In the simulations of PV system under the varying irradiance and temperature, the tracking speed and tracking accuracy of FGS-PID (scaling factors) were higher than those of ANN, ANFIS, Fuzzy, INC, P&O, PID, and FGS-PID methods. In summary, FGS-PID (scaling factors) has better performance in tracking time and accuracy than other comparison algorithms. It can improve the output efficiency of PV system in practical application.

Modelling and analysis on the mechanism of electromagnetic driven weft insertion

In view of the difficulty in improving the weaving efficiency of the projectile weaving machine based on the traditional technology principle, This research presents the electromagnetic-drive gripper weft insertion mechanism, change the existing mechanical pick principle of weft insertion, its goal is to achieve “zero transmission” friction-free high-speed weft insertion, omit complex mechanical transmission mechanism in picking shaft, and breakthrough the bottleneck of the weft insertion rate, wide fabric problem in principle. Based on the theoretical study of electromagnetic projection and electromagnetic levitation, the structural model and motion model of electromagnetic pick and electromagnetic weft are established by comparing the electromagnetic and permanent magnetic model schemes. In order to meet the requirement of electromagnetic levitation, the linear hall sensor is selected and its driving circuit is designed to obtain the real-time height value of the chip shuttle. Through the analysis of the coil response, the advantages and disadvantages of DC-DC regulation and PWM wave regulation are compared, and the high response hardware circuit of DC-DC regulation is designed. MATLAB simulation ensures the feasibility of PID regulation. The feasibility of the scheme was verified by Maxwell electromagnetic picking simulation and electromagnetic filling insertion simulation. The first phase of picking experiment and static filling insertion experiment were carried out. In order to ensure the stability, the double-row soft iron chip shuttle was used, and good experimental results were obtained, which proved the feasibility of electromagnetic suspension weft insertion scheme.

Analytic Modeling Optimal Control of Pulsed Power Supply for Accelerator Magnet

This article introduces the analytic modeling optimal control method in details, aiming at solving special control problems of pulsed power supply for heavy-ion accelerator magnet. These problems include variable waveform, high speed, high precision, and wide dynamic range. To meet these requirements, this method has been proposed as a new choice. The mathematical model is analytic function, which is concerned with the continuous dynamics during topology switching period. Moreover, based on the analytic function, the optimal duty cycle can be calculated by high-performance controller. In simulations, compared with PID regulation, this method has a better ability to track a reference waveform which has a wide dynamic range. Meanwhile, we have made simulations with two magnets and four reference waveforms. The current can be controlled to the reference value at the end of each switching cycle. In experiments, the current of power supply can track above four reference waveforms and the maximum rate of current change is 8000 A/s. There is an excellent agreement between the results of experiments and simulations. Therefore, this control method has been verified.

Fuzzy Cognitive Network by Adaptive Fuzzy PID Controller and Hybrid Optimization Algorithm

Objectives: To improve the power produced by a photovoltaic system under varying climatic circumstances and thus improving the convergence speed. Methods: To improve power in this work a Fuzzy PID regulator is implemented which is tuned by hybrid Artificial Neural Network - Particle Swarm Optimization – Simulated Annealing (ANN-PSO-SA) and FCN (Fuzzy Cognitive Network) optimization algorithm. Additionally a DC/DC help converter is employed to regulate the yield intensity of the photovoltaic system. Findings: The proposed technique works on maximum power point and improves the performances of solar energy conversion capability and maintains system stability in case of quickly unstable atmospheric rules. To the best of knowledge no PID controller or regulator has implemented this hybrid optimization algorithm along with fuzzy concepts and works with differing climatic conditions. This method achieves the advantages of the fuzzy techniques along with optimization techniques. Along with achieving maximum power the proposed controller achieves constant voltage control. The DC-DC boost converter makes use of the output of PV panel and is responsible for regulating the output power. The FCN utilized is responsible for maintaining an equilibrium condition at varying climatic conditions. Improvements: The tuned controller is compared to the conventional MPPT algorithms with specification rise time, overshoot and delay time. This is demonstrated in the comparison results shown in the results section. Keywords: DC/DC Help Converter, Fuzzy Cognitive Network (FCN), Maximum Power Point Tracking (MPPT) and Photovoltaic (PV) System

The application of isodromic equation for calculation of PID-controller integrated component

A functional feature of the application of electronics used for the automatic control of internal combustion engines is necessity in the proportional conversion of ECU electrical signals into the mechanical processes based on corresponding elements motion. For such conversion of information actuating mechanisms are used, referred as actuators. Actuators in the form of electrical machines (stepper or precision electric motors) or electric apparatuses (electromagnets and solenoids) are the mostly widespread in ICE. As a physical object of the research, the unit of Heinzmann, model StG 6-02V that is based on a DC electric drive controlled by a pulse-width modulation signal, was selected in the current work. It has a toothed gearbox and a non-contact reverse positional connection. This actuator pro-vides an output torque of 6 Nm and 36-degree range of output shaft rotational angle. The functional scheme of the electronic system of automatic control of a diesel engine based on mentioned device is developed. The PID regulator with feedback is used to control the actuator. A design formula that can be incorporated in the controller algorithm to calculate the integral component of the PID regulator was also obtained. Values of empirical coefficients were determined in this formula. The results of experimental confirmation of the correctness of the approach taken are presented. Thus, the new formula for determining the integral component of the PID regulator differs positively from the well-known solutions because the new approach is free from storing the whole array of previous data with discrepancy in the controller’s RAM, that simplifies the application of the developed algorithm greatly and speeds up the computational capability of the controller.

Integrated Control Strategy for Islanded Operation in Smart Grids: Virtual Inertia and Ancillary Services

Distributed generation has become a consolidated phenomenon in distribution grids in the last few years. Even though the matter is very articulated and complex, islanding operation of distribution grids is being considered as a possible measure to improve service continuity. In this paper, a novel static converter control strategy to obtain frequency and voltage regulation in an islanded distribution grid is proposed. Two situations are investigated: in the former, one electronic converter and one synchronous generator are present, while in the latter only static generation is available. In the first case, converter control will realize virtual inertia and efficient frequency regulation by mean of a PID regulator; this approach allows to emulate high equivalent inertia, hence limiting the rate of change of frequency and maximum frequency deviation, and, in the meantime, to obtain faster frequency regulation, which could not be possible with traditional regulators. In the second situation, a Master–Slave approach will be adopted to maximize frequency and voltage stability. Even though the presented results are obtained in a grid with only two generators, the proposed approach can be extended to more general configurations with few generation units. Simulation results confirm that the proposed control allows islanded operation with high frequency and voltage stability under heavy load variations.

SCADA Class Software of the KOGA Control system of Jig Beneficiation Node

The article presents a proprietary visualization software for the coal beneficiation process, which enables monitoring of the jig node operation and full control of trends relating to all signals from sensors installed in the system and connected to the controller, among others a movement of the float, a position of the culvert and a position of the overflow threshold. The results of analyses regarding the selection of PID regulator settings, determined on the basis of industrial research, are also presented.

Active backlight for automating visual monitoring: An analysis of a lighting control technique for Caenorhabditis elegans cultured on standard Petri plates.

Lifespan and healthspan machines can undergo C. elegans image segmentation errors due to changes in lighting conditions, which produce non-uniform images. Most C. elegans monitoring machines use backlight techniques based on the transparency of both the container and media. Backlight illumination obtains high-contrast images with dark C. elegans and a bright background. However, changes in illumination or media transparency conditions can produce non-uniform images, which are currently alleviated by image processing techniques. Besides, these machines should avoid C. elegans exposure to light as much as possible because light stresses worms, and can even affect their lifespan, mainly when using (1) long exposure times, (2) high intensities or (3) wavelengths that come close to ultraviolet. However, if short exposure of worms to light is required for visual monitoring, then light can also be used as a movement stimulus. In this paper, an active backlight method is analysed. The proposed method consists of controlling the light intensities and wavelengths of an illumination dots matrix with PID regulators. These regulators adapt illumination to some changing conditions. The experimental results shows that this method simplifies the image segmentation problem because it is able to automatically compensate not only changes in media transparency throughout assay days, but also changes in ambient conditions, such as smooth condensation on the lid and light derivatives of the illumination source during its lifetime. In addition, the strategic application of wavelengths could be adapted for the requirements of each assay. For instance, a specific control strategy has been proposed to minimise stress to worms and trying to stimulate C. elegans movement in lifespan assays.

Compare of Transient Quality in Automatic Control Systems with Classic PID Algorithm and Optimal Regulator

Currently, about 90–95% of generic controllers use the PID algorithm to generate control actions, while 64% of the PID controllers are used in single-circuit automatic control systems. Most of industries (power industry among them) use hundreds of automatic control systems. The quality of their work is the basis of economic efficiency of technical processes, ensuring safety, reliability, durability and environmental friendliness of both technological equipment and automation equipment. There are different modifications of PID-controller structure implementation. In practice the ideal PID controller with a filter and the classic PID regulator (serial connection of the ideal PI controller and the real PD regulator as the direct action elements) are widely used. The problem of choosing a rational structure and a method of parametric optimization of PID controllers, which provide the best direct indicatives of the quality in the development of the main effects in single-circuit automatic control systems, becomes urgent. However, only for the classical PID controllers, which are widely used at present, there are more than three hundred methods for adjusting the three parameters of the optimal dynamic adjustment, as well as the ballast time constant. This results in arising a problem of substantiation of the best structure and method of parametric optimization of classical PID regulators. As a basic option, one of the simplest and most obvious one, viz. the method of automated adjustment of the controller in the Simulink MatLab environment had been chosen, which was compared with the method of full compensation in general for objects with a transfer function in the form of an inertial link with a conditional delay. Two variants of control action realization on the basis of the structural scheme of the optimal regulator developed by the Belarusian national technical University were also offered. In contrast with the classic PID controller, the optimal controller has one parameter of dynamic adjustment setting. The results of simulation of transients at basic perturbations confirmed that the best direct indicatives of the quality are provided with an optimal regulator, which makes it possible to recommend it for wide implementation instead of the classic PID controllers.