The Experts below are selected from a list of 765 Experts worldwide ranked by ideXlab platform
Mohammad Saleh Tavazoei - One of the best experts on this subject based on the ideXlab platform.
-
On time-constant robust tuning of fractional order proportional derivative controllers
IEEE CAA Journal of Automatica Sinica, 2019Co-Authors: Vahid Badri, Mohammad Saleh TavazoeiAbstract:This paper deals with analyzing a newly introduced method for tuning of fractional order [ proportional derivative ] ( FO[ PD ] ) controllers to be used in motion control. By using this tuning method, not only the phase margin and Gain Crossover Frequency are adjustable, but also robustness to variations in the plant time-constant is guaranteed. Conditions on the values of control specifications ( desired phase margin and Gain Crossover Frequency ) for solution existence in this tuning method are found. Also, the number of solutions is analytically determined in this study. Moreover, experimental verifications are presented to indicate the applicability of the obtained results.
-
Robust Control of a Class of Fractional Order Plants in the Presence of Pole Uncertainty
Electrical Engineering (ICEE) Iranian Conference on, 2018Co-Authors: Mohammad Hossein Basiri, Mohammad Saleh TavazoeiAbstract:In recent years some approaches for robust control of plants with uncertainty in their poles have been suggested. Recently a new approach for tuning controllers has been introduced that can preserve phase margin in desirable value despite large variations in location of one of the poles and also it is able to provide required Gain Crossover Frequency in the nominal case. In this paper by benefiting from this approach, a fractional order proportional derivative controller is introduced to control the plants with fractional order transfer function with uncertainty in their poles with order in the range (1, 2). Also, sufficient conditions on design specifications and plant parameters for ensuring applicability of the controller are derived. In addition, achievable region for the proposed FO[PD] controller is determined both analytically and graphically. Utilizing this proposed robust controller, not only gives desirable phase margin and Gain Crossover Frequency in the nominal value of the pole but also it preserves phase margin despite large variations in location of the uncertain pole. Numerical examples will show the effectiveness of the proposed controller.
-
An Efficient Method for Tuning of FOPI Controllers: Robustness to Order Variations of the Plant
Electrical Engineering (ICEE) Iranian Conference on, 2018Co-Authors: Mohammad Hossein Basiri, Mohammad Saleh TavazoeiAbstract:Existence of uncertainties in the model of real-world plants can trouble the control system designer in achievement of control objectives in control of such plants. In modeling of these plants by benefiting from fractional order models, one of the most commonplace types of uncertainties is the order uncertainty. This paper deals with presenting a method for tuning fractional order PI (FOPI) controllers to be used in control of plants, modeled by fractional order transfer functions consisting of a fractional order pole in addition to a time delay, such that the control system is robust aGainst order variations. By the proposed tuning method, values of phase margin and Gain Crossover Frequency are adjustable in the nominal case. Furthermore, the resulting control system will be robust aGainst order uncertainties. Numerical simulation results are presented to confirm the effectiveness of the proposed tuning method.
-
Some Analytical Results on Tuning Fractional-Order [Proportional–Integral] Controllers for Fractional-Order Systems
IEEE Transactions on Control Systems Technology, 2016Co-Authors: Vahid Badri, Mohammad Saleh TavazoeiAbstract:The first objective of this brief is to discover the solution existence conditions in the methods recently proposed for tuning fractional-order [proportional–integral] (FO-[PI]) controllers. The FO-[PI] controller tuned by these methods can simultaneously ensure the desired phase margin, the desired Gain Crossover Frequency, and the flatness of the phase Bode plot at such a Frequency. In this brief, the achievable performance region of these tuning methods is also found in the Gain Crossover Frequency–phase margin plane. Moreover, some results on the shape of this region and the uniqueness of the controller resulting from the considered tuning methods are given. By combining the presented results and those previously obtained on fractional-order [proportional–derivative] tuning methods, a useful result on the fractional-order control system design is derived. In addition, simplified forms for tuning methods previously proposed in the literature are obtained. Also to verify the practical usefulness of outcomes of this brief, some experimental results on velocity control of a dc motor are presented.
-
On Robust Control of Fractional Order Plants: Invariant Phase Margin
Journal of Computational and Nonlinear Dynamics, 2015Co-Authors: Mohammad Hossein Basiri, Mohammad Saleh TavazoeiAbstract:Recently, a robust controller has been proposed to be used in control of plants with large uncertainty in location of one of their poles. By using this controller, not only the phase margin and Gain Crossover Frequency are adjustable for the nominal case but also the phase margin remains constant, notwithstanding the variations in location of the uncertain pole of the plant. In this paper, the tuning rule of the aforementioned controller is extended such that it can be applied in control of plants modeled by fractional order models. Numerical examples are provided to show the effectiveness of the tuned controller.
Yangquan Chen - One of the best experts on this subject based on the ideXlab platform.
-
ON AUTO-TUNING OF FRACTIONAL ORDER PIλDµ CONTROLLERS
2015Co-Authors: Concepción A. Monje, Yangquan Chen, Blas M. Vinagre, Vicente Feliu, Escuela De Ingenierías Industriales, Extremadura Badajoz SpainAbstract:Abstract: In this paper, a method for the auto-tuning of fractional order PIλDµ controllers using relay feedback tests is proposed. A design method for this kind of controllers is discussed, based on the magnitude and phase measurement of the plant to be controlled from relay feedback tests at a Frequency of interest. Simple relationships among the parameters of the fractional controller are established and specifications such as the static error constant (kss), phase margin (ϕm) and Gain Crossover Frequency (ωc) can be fulfilled, with a robustness argument by inspecting the flatness of phase Bode plot of the controller. An illustrative example of application is presented to show the reliability and effectiveness of the method
-
CDC-ECE - Stabilizing and robust FOPI controller synthesis for first order plus time delay systems
IEEE Conference on Decision and Control and European Control Conference, 2011Co-Authors: Ying Luo, Yangquan ChenAbstract:For all first order plus time delay (FOPTD) systems, a fractional order PI (FOPI) or a traditional integer order PID (IOPID) controller can be designed to fulfill three design specifications: Gain Crossover Frequency, phase margin, and a flat phase constraint simultaneously. In this paper, a guideline for choosing feasible or achievable Gain Crossover Frequency and phase margin specifications, and a new FOPI/IOPID controller synthesis are proposed for all FOPTD systems. Using this synthesis scheme, the complete feasible region of the Gain Crossover Frequency and phase margin can be obtained and visualized in the plane. With this region as the prior knowledge, all combinations of the phase margin and Gain Crossover Frequency can be verified before the controller design. Only if the combination is chosen from this achievable region, the existence of the stabilizing and desired FOPI/IOPID controller design can be guaranteed. Especially, it is interesting to compare the areas of these two feasible regions for the IOPID controller and the FOPI controller. This area comparison reveals, for the first time, the potential advantages of one controller over the other in terms of achievable performances. As a basic step, a scheme for finding the stabilizing region of the FOPI/IOPID controller is presented first, and then a new scheme for designing a stabilizing FOPI/IOPID controller satisfying the given Gain Crossover Frequency, phase margin and flat phase constraint is proposed in details. Thereafter, the complete information about the feasible region of Gain Crossover Frequency and phase margin is collected. This feasible region for the FOPI controller is compared with that for the traditional IOPID controller. This area comparison shows the advantage of the FOPI over the traditional IOPID clearly. Simulation illustration is presented to show the effectiveness and the performance of the designed FOPI controller comparing with the designed IOPID controller following the same synthesis in this paper.
-
a fractional order proportional and derivative fopd motion controller tuning rule and experiments
IEEE Transactions on Control Systems and Technology, 2010Co-Authors: Ying Luo, Yangquan ChenAbstract:In recent years, it is remarkable to see the increasing number of studies related to the theory and application of fractional order controller (FOC), specially PI ? D ? controller, in many areas of science and engineering. Research activities are focused on developing new analysis and design methods for fractional order controllers as an extension of classical control theory. In this paper, a new tuning method for fractional order proportional and derivative (PD ?) or FO-PD controller is proposed for a class of typical second-order plants. The tuned FO-PD controller can ensure that the given Gain Crossover Frequency and phase margin are fulfilled, and furthermore, the phase derivative w. r. t. the Frequency is zero, i.e., the phase Bode plot is flat at the given Gain Crossover Frequency. Consequently, the closed-loop system is robust to Gain variations. The FOC design method proposed in the paper is practical and simple to apply. Simulation and experimental results show that the closed-loop system can achieve favorable dynamic performance and robustness.
-
FRACTIONAL ORDER PROPORTIONAL DERIVATIVE (FOPD) AND FO(PD) CONTROLLER DESIGN FOR NETWORKED POSITION SERVO SYSTEMS
Volume 4: 7th International Conference on Multibody Systems Nonlinear Dynamics and Control Parts A B and C, 2009Co-Authors: Yongshun Jin, Yangquan Chen, Chunyang Wang, Ying LuoAbstract:This paper considers the fractional order proportional derivative (FOPD) controller and fractional order [propor tional derivative] (FO[PD]) controller for networked position se rvo systems. The systematic design schemes of the networked position servo system with a time delay are presented. It follo ws from the Bode plot of the FOPD system and the FO[PD] that the given Gain Crossover Frequency and phase margin are fulfille d. Moreover, the phase derivative w.r.t. the Frequency is zero , which means that the closed-loop system is robust to Gain variatio ns at the given Gain Crossover Frequency. However, sometimes w e can not get the controller parameters to meet our robustnessrequirement. In this paper, we have studied on this situation a nd presented the requirement of the Gain cross Frequency, and p hase margin in the designing process. For the comparison of fractional order controllers with traditional integer order co ntroller, the integer order proportional integral differential (IOP ID) was also designed by using the same proposed method. The simulation results have verified that FOPD and FO[PD] are effective for networked position servo. The simulation results also r eveal
-
a fractional order proportional and derivative fopd controller tuning algorithm
Chinese Control and Decision Conference, 2008Co-Authors: Hong Sheng Li, Yangquan ChenAbstract:In recent years, it is remarkable to see the increasing number of studies related to the theory and application of fractional order controller (FOC), especially PID controller, in many areas of science and engineering. Research activities are focused on developing new analysis and design methods for fractional order controllers as an extension of classical control theory. In this paper, a new tuning method for fractional order proportional and derivative (PD) or FOPD controller is proposed for a class of typical second-order plants. The tuned PD controller can ensure that the given Gain Crossover Frequency and phase margin are fulfilled, and furthermore the phase derivative w.r.t. the Frequency is zero, i.e., phase bode plot is flat, at the given Gain Crossover Frequency so that the closed-loop system is robust to Gain variations and the step response exhibits an iso-damping property. The FOC design method proposed in the paper is practical and simple to apply. Simulation results show that the closed-loop system can achieve favorable dynamic performance and robustness.
Vahid Badri - One of the best experts on this subject based on the ideXlab platform.
-
On time-constant robust tuning of fractional order proportional derivative controllers
IEEE CAA Journal of Automatica Sinica, 2019Co-Authors: Vahid Badri, Mohammad Saleh TavazoeiAbstract:This paper deals with analyzing a newly introduced method for tuning of fractional order [ proportional derivative ] ( FO[ PD ] ) controllers to be used in motion control. By using this tuning method, not only the phase margin and Gain Crossover Frequency are adjustable, but also robustness to variations in the plant time-constant is guaranteed. Conditions on the values of control specifications ( desired phase margin and Gain Crossover Frequency ) for solution existence in this tuning method are found. Also, the number of solutions is analytically determined in this study. Moreover, experimental verifications are presented to indicate the applicability of the obtained results.
-
Some Analytical Results on Tuning Fractional-Order [Proportional–Integral] Controllers for Fractional-Order Systems
IEEE Transactions on Control Systems Technology, 2016Co-Authors: Vahid Badri, Mohammad Saleh TavazoeiAbstract:The first objective of this brief is to discover the solution existence conditions in the methods recently proposed for tuning fractional-order [proportional–integral] (FO-[PI]) controllers. The FO-[PI] controller tuned by these methods can simultaneously ensure the desired phase margin, the desired Gain Crossover Frequency, and the flatness of the phase Bode plot at such a Frequency. In this brief, the achievable performance region of these tuning methods is also found in the Gain Crossover Frequency–phase margin plane. Moreover, some results on the shape of this region and the uniqueness of the controller resulting from the considered tuning methods are given. By combining the presented results and those previously obtained on fractional-order [proportional–derivative] tuning methods, a useful result on the fractional-order control system design is derived. In addition, simplified forms for tuning methods previously proposed in the literature are obtained. Also to verify the practical usefulness of outcomes of this brief, some experimental results on velocity control of a dc motor are presented.
-
Fractional order control of thermal systems: achievability of Frequency-domain requirements
Nonlinear Dynamics, 2015Co-Authors: Vahid Badri, Mohammad Saleh TavazoeiAbstract:Fractional order models have been widely used in modeling and identification of thermal systems. General model in this category is considered as the model of thermal systems in this paper, and a fractional order controller is proposed for controlling such systems. The proposed controller is a generalization for the traditional PI controllers. The parameters of this controller can be obtained by using a recently introduced tuning method which can simultaneously ensure the following three requirements: desired phase margin, desired Gain Crossover Frequency, and flatness of the phase Bode plot at this Frequency. In this paper, it is found whether simultaneously achieving the mentioned Frequency-domain requirements will be possible in the control of the considered thermal systems. Numerical examples are presented to show the usefulness of the obtained results.
-
Achievable Performance Region for a Fractional-Order Proportional and Derivative Motion Controller
IEEE Transactions on Industrial Electronics, 2015Co-Authors: Vahid Badri, Mohammad Saleh TavazoeiAbstract:In recent years, design and tuning of fractional-order controllers for use in motion control have attracted much attention. This paper deals with one of the interesting methods that have been recently proposed for tuning fractional-order proportional and derivative (FOPD) motion controllers. The FOPD controller tuned based on the considered method results in simultaneously meeting the desired phase margin, the desired Gain Crossover Frequency, and the flatness of the phase Bode plot at such a Frequency. Since, in this tuning method, the derivative parameter and order are determined in a graphical way, in the first view, it is not clear for which pairs of phase margin and Gain Crossover Frequency an FOPD controller can be found to satisfy the mentioned specifications. In this paper, necessary and sufficient conditions are presented via an analytical approach to check the solution existence of the considered tuning method in both cases of absence and presence of time delay in feedback loop. Furthermore, the uniqueness of the controller parameters obtained from the method is investigated. Moreover, some numerical and experimental examples are presented to confirm the analytical results of this paper.
-
On tuning FO[PI] controllers for FOPDT processes
Electronics Letters, 2013Co-Authors: Vahid Badri, Mohammad Saleh TavazoeiAbstract:A method recently proposed for tuning fractional order [proportional integral] (FO[PI]) controllers is investigated. This tuning method, when applied in control of first-order plus dead time (FOPDT) processes, can ensure the desired phase margin, the desired Gain Crossover Frequency and the flatness of the phase Bode plot at such a Frequency. The necessary and sufficient condition for the applicability of the aforementioned tuning method is derived. Also, it is shown that this condition can be used in obtaining the achievable performance region of the tuning method in the Gain Crossover Frequency-phase margin plane.
Isabela R. Birs - One of the best experts on this subject based on the ideXlab platform.
-
A real life implementation of fractional order event based PI control
2020 IEEE International Conference on Automation Quality and Testing Robotics (AQTR), 2020Co-Authors: Isabela R. Birs, Cristina I. Muresan, Roxana Both, Ioan NascuAbstract:The paper presents a novel generalization of available integer-order event based control strategies into the fractional order field, offering a real life implementation possibility of event based fractional order control. A fractional order Proportional Integral (FOPI) controller is tuned using a set of Frequency domain specifications such as Gain Crossover Frequency, phase margin and robustness. A generalized theoretical approach is developed for FOPI event based control strategies. In addition, real-life solutions are provided in order to implement the FOPI controller on a Vertical Take-Off and Landing (VTOL) platform. The proposed methodology is validated experimentally by assessing the closed loop system performance in various scenarios such as step reference tracking, disturbance rejection and robustness to Gain uncertainties.
-
ICCMA - Design and Practical Implementation of a Fractional Order Proportional Integral Controller (FOPI) for a Poorly Damped Fractional Order Process with Time Delay
2019 7th International Conference on Control Mechatronics and Automation (ICCMA), 2019Co-Authors: Isabela R. Birs, Cristina I. Muresan, Ioan Nascu, Dana Copot, Clara M. IonescuAbstract:One of the most popular tuning procedures for the development of fractional order controllers is by imposing Frequency domain constraints such as Gain Crossover Frequency, phase margin and iso-damping properties. The present study extends the Frequency domain tuning methodology to a gen-eralized range of fractional order processes based on second order plus time delay (SOPDT) models. A fractional order PI controller is tuned for a real process that exhibits poorly damped dynamics characterized in terms of a fractional order transfer function with time delay. The obtained controller is validated on the experimental platform by analyzing staircase reference tracking, input disturbance rejection and robustness to process uncertainties. The paper focuses around the tuning methodology as well as the fractional order modeling of the process’ dynamics.
-
Tuning of fractional order proportional integral/proportional derivative controllers based on existence conditions:
Proceedings of the Institution of Mechanical Engineers Part I: Journal of Systems and Control Engineering, 2018Co-Authors: Cristina I. Muresan, Clara M. Ionescu, Isabela R. Birs, Robain De KeyserAbstract:Fractional order proportional integral and proportional derivative controllers are nowadays quite often used in research studies regarding the control of various types of processes, with several papers demonstrating their advantage over the traditional proportional integral/proportional derivative controllers. The majority of the tuning techniques for these fractional order proportional integral/fractional order proportional derivative controllers are based on three Frequency-domain specifications, such as the open-loop Gain Crossover Frequency, phase margin and the iso-damping property. The tuning parameters of the controllers are determined as the solution of a system of three nonlinear equations resulting from the performance criteria. However, as with any system of nonlinear equations, it might occur that for a certain process and with some specific performance criteria, the computed parameters of the fractional order proportional integral/fractional order proportional derivative controllers do not fall into a range of values with correct physical meaning. In this article, a study regarding this limitation, as well as the existence conditions for the fractional order proportional integral/fractional order proportional derivative parameters are presented. The method could also be extended to the more complex fractional order proportional-integral-derivative controller. The aim of this research is directed toward demonstrating that when designing fractional order proportional integral/fractional order proportional derivative controllers, the choice of the performance specifications should be done based on some specific design constraints. The article shows that given a specific process and open-loop modulus and phase specifications, the Gain Crossover Frequency (or in general, a certain test Frequency used in the design), specified as a performance specification, must be selected such that the process phase fulfills an important condition (design constraint). Once this is met, the proposed approach ensures that the tuning parameters of the fractional order controller will have a physical meaning. Illustrative examples are included to validate the results.
-
ICARCV - Experimental results of fractional order PI controller designed for second order plus dead time (SOPDT) processes
2018 15th International Conference on Control Automation Robotics and Vision (ICARCV), 2018Co-Authors: Isabela R. Birs, Cristina I. Muresan, Ioan Nascu, Silviu Folea, Clara M. IonescuAbstract:The present paper presentes the tuning of a Fractional Order Proportional Integral (FOPI) controller for second-order-plus-time-delay (SOPDT) plants. The tuning procedure is based on imposing Frequency domain constraints for the open loop system with the FOPI controller and the SOPDT plant. The Gain Crossover Frequency, phase margin and the iso-damping property that guarantees a certain degree of robustness to Gain variations are imposed in order to obtain the parameters of the fractional order controller. The proposed method is validated by real life implementation on a process whose dynamics are approximated to a SOPDT model. The settling time, steady state error, robustness and disturbance rejection capabilities are analyzed using experimental test cases.
-
Analytical modeling and preliminary fractional order velocity control of a small scale submersible
2018 SICE International Symposium on Control Systems (SICE ISCS), 2018Co-Authors: Isabela R. Birs, Cristina I. Muresan, Silviu Folea, Ovidiu Prodan, Clara M. IonescuAbstract:This paper presents the modeling and control of a small scale submersible equipped with one propeller. The modeling process takes into consideration physical elements such as fluid statics, viscous damping and propulsive thrust. A first order transfer function with time delay is developed to make the connection between the voltage applied to the motor actuating the propeller and the velocity of the submersible. The velocity control is realized with a Fractional Order Proportional Integral (FOPI) controller that ensures zero steady state error. The controller is designed based on Frequency domain specifications such as Gain Crossover Frequency, phase margin and robustness to Gain variations. The obtained fractional controller is validated through simulation in terms of steady state error and disturbance rejection performance.
Cristina I. Muresan - One of the best experts on this subject based on the ideXlab platform.
-
A real life implementation of fractional order event based PI control
2020 IEEE International Conference on Automation Quality and Testing Robotics (AQTR), 2020Co-Authors: Isabela R. Birs, Cristina I. Muresan, Roxana Both, Ioan NascuAbstract:The paper presents a novel generalization of available integer-order event based control strategies into the fractional order field, offering a real life implementation possibility of event based fractional order control. A fractional order Proportional Integral (FOPI) controller is tuned using a set of Frequency domain specifications such as Gain Crossover Frequency, phase margin and robustness. A generalized theoretical approach is developed for FOPI event based control strategies. In addition, real-life solutions are provided in order to implement the FOPI controller on a Vertical Take-Off and Landing (VTOL) platform. The proposed methodology is validated experimentally by assessing the closed loop system performance in various scenarios such as step reference tracking, disturbance rejection and robustness to Gain uncertainties.
-
ICCMA - Design and Practical Implementation of a Fractional Order Proportional Integral Controller (FOPI) for a Poorly Damped Fractional Order Process with Time Delay
2019 7th International Conference on Control Mechatronics and Automation (ICCMA), 2019Co-Authors: Isabela R. Birs, Cristina I. Muresan, Ioan Nascu, Dana Copot, Clara M. IonescuAbstract:One of the most popular tuning procedures for the development of fractional order controllers is by imposing Frequency domain constraints such as Gain Crossover Frequency, phase margin and iso-damping properties. The present study extends the Frequency domain tuning methodology to a gen-eralized range of fractional order processes based on second order plus time delay (SOPDT) models. A fractional order PI controller is tuned for a real process that exhibits poorly damped dynamics characterized in terms of a fractional order transfer function with time delay. The obtained controller is validated on the experimental platform by analyzing staircase reference tracking, input disturbance rejection and robustness to process uncertainties. The paper focuses around the tuning methodology as well as the fractional order modeling of the process’ dynamics.
-
Tuning of fractional order proportional integral/proportional derivative controllers based on existence conditions:
Proceedings of the Institution of Mechanical Engineers Part I: Journal of Systems and Control Engineering, 2018Co-Authors: Cristina I. Muresan, Clara M. Ionescu, Isabela R. Birs, Robain De KeyserAbstract:Fractional order proportional integral and proportional derivative controllers are nowadays quite often used in research studies regarding the control of various types of processes, with several papers demonstrating their advantage over the traditional proportional integral/proportional derivative controllers. The majority of the tuning techniques for these fractional order proportional integral/fractional order proportional derivative controllers are based on three Frequency-domain specifications, such as the open-loop Gain Crossover Frequency, phase margin and the iso-damping property. The tuning parameters of the controllers are determined as the solution of a system of three nonlinear equations resulting from the performance criteria. However, as with any system of nonlinear equations, it might occur that for a certain process and with some specific performance criteria, the computed parameters of the fractional order proportional integral/fractional order proportional derivative controllers do not fall into a range of values with correct physical meaning. In this article, a study regarding this limitation, as well as the existence conditions for the fractional order proportional integral/fractional order proportional derivative parameters are presented. The method could also be extended to the more complex fractional order proportional-integral-derivative controller. The aim of this research is directed toward demonstrating that when designing fractional order proportional integral/fractional order proportional derivative controllers, the choice of the performance specifications should be done based on some specific design constraints. The article shows that given a specific process and open-loop modulus and phase specifications, the Gain Crossover Frequency (or in general, a certain test Frequency used in the design), specified as a performance specification, must be selected such that the process phase fulfills an important condition (design constraint). Once this is met, the proposed approach ensures that the tuning parameters of the fractional order controller will have a physical meaning. Illustrative examples are included to validate the results.
-
ICARCV - Experimental results of fractional order PI controller designed for second order plus dead time (SOPDT) processes
2018 15th International Conference on Control Automation Robotics and Vision (ICARCV), 2018Co-Authors: Isabela R. Birs, Cristina I. Muresan, Ioan Nascu, Silviu Folea, Clara M. IonescuAbstract:The present paper presentes the tuning of a Fractional Order Proportional Integral (FOPI) controller for second-order-plus-time-delay (SOPDT) plants. The tuning procedure is based on imposing Frequency domain constraints for the open loop system with the FOPI controller and the SOPDT plant. The Gain Crossover Frequency, phase margin and the iso-damping property that guarantees a certain degree of robustness to Gain variations are imposed in order to obtain the parameters of the fractional order controller. The proposed method is validated by real life implementation on a process whose dynamics are approximated to a SOPDT model. The settling time, steady state error, robustness and disturbance rejection capabilities are analyzed using experimental test cases.
-
Analytical modeling and preliminary fractional order velocity control of a small scale submersible
2018 SICE International Symposium on Control Systems (SICE ISCS), 2018Co-Authors: Isabela R. Birs, Cristina I. Muresan, Silviu Folea, Ovidiu Prodan, Clara M. IonescuAbstract:This paper presents the modeling and control of a small scale submersible equipped with one propeller. The modeling process takes into consideration physical elements such as fluid statics, viscous damping and propulsive thrust. A first order transfer function with time delay is developed to make the connection between the voltage applied to the motor actuating the propeller and the velocity of the submersible. The velocity control is realized with a Fractional Order Proportional Integral (FOPI) controller that ensures zero steady state error. The controller is designed based on Frequency domain specifications such as Gain Crossover Frequency, phase margin and robustness to Gain variations. The obtained fractional controller is validated through simulation in terms of steady state error and disturbance rejection performance.
