PI Controller Design Research Articles

Synchronized cell balancing charging of supercapacitors using PI control

This paper covers the synchronized cell balancing charging of supercapacitors using pi control. The main objective of this project is to design a balanced circuit for supercapacitor and balance the voltage for each supercapacitor in series using pi control. This project aims to introduce a switch resistor design for a supercapacitor to balance the cell. Due to its low cost, easy to implement, and charge/discharge, the switch resistor design was chosen as the balanced circuit. The switch resistor design process was accomplished taking into account all the calculation for the design parameters. Using the pi control given to the circuit the stability and balancing in the voltage. The pi control design process was accomplished with the calculation for the design parameters.

On Fractional Order Predictive PI Controller Design for a MIMO Reactive Distillation Process

Abstract In this paper, fractional-order predictive PID control scheme is applied in composition control of boiling fractions of a reactive distillation plant set up for the esterification reaction between acetic acid and ethanol. The controller shares similar structural features with Model-based Predictive Controller (MPC) as many attractive benefits of Dynamic Matrix Control (DMC) are retained such as constraint handling capability. However, it optimizes a different objective function formulated to achieve a more robust control action. These robust properties make it attractive to multivariable process control applications. Process’s state space model is assumed to be available and the model is augmented for prediction of future outputs. Thereafter, a structured cost function is defined which retains the design objective of fractional-order predictive PI controller. Optimisation of this cost function results in realising a near-optimal MIMO controller with reduced input control efforts. Simulation studies using Giwa’s reactive distillation column demonstrates better control performance over dynamic matrix control of the same system. It also rejects disturbances, both measured and unknown disturbances, better than Dynamic Matrix Control system under similar conditions. A major contribution of this paper is the development of a MIMO fractional order predictive PI controller for multivariable process control applications such as composition control of a reactive distillation column.

Design and Performance Evaluation of a Solar Assisted 25kW PMSM Drive for Four Wheeler Electric Car.

This paper presents a complete design and control of solar assisted passenger car electric engine which aims to overcome the disadvantages associated with present E-Rickshaw. Here a permanent magnet synchronous motor (PMSM) drive is considered as main electric engine fed from Battery and Solar PV cell. Generally in VSI fed PMSM drive the dc input voltage to the inverter is kept constant irrespective of the load demand. This leads to more losses in the dc bus and overall efficiency of the system decreases. This paper presents a noble control technique with variable dc link voltage to improve the efficiency of the PMSM drive by minimizing the dc link power losses. An additional separate PI controller is used to control the dc link voltage which adjusts dc- link voltage indirectly. The design of PI controller with basic principles is illustrated and the necessary conditions are analyzed. This control scheme is tested with a 25kW Permanent magnet synchronous motor (PMSM) drive suitable for application in electric vehicle. The effectiveness of the system is verified through simulation using Simulink/ MATLAB.

Design of Robust PI Controller with Decoupler for a Fluid Catalytic Cracking Unit

In this work, a decoupling control system is designed for the riser section of the fluid catalytic cracking unit (FCCU). The decentralized control system is implemented on FCCU to estimate the magnitude of the interactions using relative gain array (RGA). Interactions among the loops are minimized by applying the decoupling control strategy to decentralized FCCU. Relative normalized gain array and dynamic relative gain array (dRGA) are computed for the closed-loop FCCU and used to design the decouplers for the process. The advantages of the decoupling control strategy are a simple design and it does not need extensive calculations. This method gives a dynamic decoupler in the form of lead/lag modules with time delays. PI controllers can be designed efficiently for controlling the riser temperature, mass fractions of gasoline, and LPG. The decentralized controller and the decoupling control system performances are studied on the basis of the closed-loop performance of control variables, and it is found tha...

Design of Adaptive Fuzzy PI Controller for Electric Vehicle with BLDC Drives

Electric vehicles in concern with its innumerable advantages, replaces the internal combustion engine vehicles (ICEV). The efficiency and performance of the Electric Vehicle (EV) depends mainly on the electric motor and its control technique. The Brushless DC (BLDC) Motor is used as the electric motor in the EV as it has high efficiency and high starting torque. The sensorless direct torque control technique is used to enhance the performance of the EV. The Adaptive Fuzzy PI (AFPI) Controller is the proposed controller in the EV. The comparison of reference torque and actual torque produce the error. It is applied to the AFPI controller which produces an output of reference torque. The EV with stationary reference frame theory of direct torque control with AFPI controller is simulated using MATLAB/SIMULINK.

Design of PI controller for Liquid Level System using Siemens Distributed Control System

The PI controller design for a liquid level system using the weighted geometric center method is discussed. Every real-time process have dead time. This dead time leads to the generation of oscillation in the system response. The oscillation generated due to dead time introduces instability in system performance. This paper presents a tuning method based on calculating a geometric center in the stability region for a higher order system. In this, the stability region calculated by plotting (Kp, Ki)-plane based on boundary locus stability technique. Further centre point computed in the stability locus by a geometric center method. This center point will provide Kp, Ki value for tuning the PI controller. The First Order Plus Dead Time (FOPDT) process considered to elaborate the method for computing the tuning parameters. A nonlinear time-delay system and a plant having time-delay response are controlled in simulation. The performance of the newly obtained PI controller based on weighted geometric center method is compared with the existing results to show the usefulness of the control scheme. Moreover, disturbance rejection ability of the newly obtained PI controller based on weighted geometric center method is demonstrated by applying disturbances. In addition, the designed controller implemented using Siemens DCS PCS7 V8.1 platform.

An adaptive PI control design for multi-phase machines in healthy and faulty operations

Purpose This paper aims to present a novel robust control method based on an adaptive PI controller (APIC) to compensate for different disturbances and unknown dynamics for multi-phase induction machines.Design/methodology/approach The gains of the APIC are adapted online according to the tracking error. Proposed APIC is accompanied with designed linear disturbance observer (LDO) to present robust behavior to machine parameter variations and fault disturbances.Findings The results show remarkable dynamic performance in both healthy and faulty conditions when the six-phase induction machine works under APIC and LDO schemes.Originality/value The proposed controller need not readjust current controllers for the post-fault condition. The developed Simulink model efficiency is confirmed through experimental tests.

Decision making scheme of integration design and control under uncertainty for enhancing the economic performance of chemical processes with multiplicity behaviors

In this paper, a robust decision-making strategy for integration of design and control under uncertainty is developed for multiple steady-state processes. The major challenge in the integration of design and control is the presence of disturbances and process uncertainty, particularly in the nonlinear process with multiple steady states. A fuzzy model is used as a surrogate model to reduce computational loading in a large operating scope in this work. Based on fuzzy model rules, a robust PI controller design using linear matrix inequalities is developed to guarantee the disturbance rejection performance, stability, and robustness. Finally, through an illustrative process with multiplicity behaviors, the features of the proposed method are demonstrated. Comparisons between the proposed method and the conventional sequential approach are made. The resulting design shows that the proposed method under the designed process with uncertainty would gain more profits than the past design approaches.

Design and Simulation of PI Controller with Two Degrees of Freedom

Aiming at the fully coupled problem of steady state and dynamic performance of a PI controller with one degree of freedom, two kinds of two DOF PI controllers were designed based on the setpoint filter structure and the setpoint feed-forward structure, and the design method of compensation link was introduced.On this basis, a variable structure two-degree-of-freedom PI controller was designed with reference to the idea of variable gain PI controller.Finally, the simulation results show that the controller can not only simplify the process of setting control parameters, but also take into account the steady-state performance, dynamic performance and anti-jamming performance of the system, and realize the function of output fast, no overshoot, no error tracking input signal changes.

Design and Simulation of Variable Structure PI Controller

Aiming at the poor performance of IP control system in tracking continuously varying input signals, a variable structure PI controller was proposed, which can eliminate overshoot of step response and track continuously varying input signals without error. The controller performs as an IP controller for step input signals and a PI controller for continuously changing input signals. Firstly, the control performance defects of traditional IP controller were analyzed, and then the structure of variable structure PI controller was built. Finally, the simulation results show that the VSPI and IP control systems have the same control effect when the step signal is input. Compared with PI control system, the VSPI and IP control systems not only have no overshoot but also have better response stability. When the input is a continuous sinusoidal signal, VSPI and PI can track the input signal almost without error, and the control effect is obviously better than IP control. The anti-jamming performance of the system is inversely proportional to the bandwidth value, but has nothing to do with the control mode.

Process-Identification and Design of Robust PI Controller for a Self-Oscillating Integral Process with Dead Time

Process-Identification and Design of Robust PI Controller for a Self-Oscillating Integral Process with Dead Time

Microprocessor based prototype design of a PMDC motor with its system identification and PI controller design

This paper describes the development process of a permanent magnetic direct current (PMDC) motor prototype in details. The designed prototype is used for speed control purposes. The developed model is intended to have two types of inputs: one is analog input which accepts variable direct voltage for system identification purpose, and the other is the pulse width modulation input, which can be used to interface with the outside world such as microcontrollers or programmable logic controllers. A microprocessor (with 8 bit resolution and a high performance RISC CPU) acts as a core of the module as it accepts the inputs and accordingly provides the output. An IR sensor acts as feedback sensor and provides pulses to the microprocessor which performs frequency to voltage (F/V) converting function and gives a variable output direct voltage as the speed of the motor varies. The actuator is a permanent magnetic direct current motor driven using metal oxide semiconductor field effect transistor based driving circuit. A four stages magnetic load mechanism is attached to the motor shaft. For test experiment, an ARDUINO MEGA MATLAB SIMULINK support package-based module is developed to provide the inputs and measure the outputs, then open loop test, system identification and PI controller design are carried out and satisfying results are obtained. Illustrating the detailed procedure and the step by step work of the design process of the PMDC motor prototype is the main contribution of current work.

Design of Adaptive PI Controller of STATCOM for Voltage Stability

Design of Adaptive PI Controller of STATCOM for Voltage Stability

PI based indirect-type iterative learning control for batch processes with time-varying uncertainties: A 2D FM model based approach

A robust PI based indirect-type iterative learning control (ILC) is proposed in this paper for industrial batch processes with time-varying uncertainties, based on a two-dimensional (2D) Fornasini-Marchesini (FM) model description of the batch process dynamics. An important merit is that the proposed ILC design is independent of the PI tuning in the closed-loop system, owing to that the ILC updating law is only implemented through tuning the set-point of the closed-loop system. By introducing a specified pole location of the closed-loop system, a robust PI controller design is firstly given with the H infinity performance index to maintain the closed-loop robust stability. Then by developing a 2D FM description of the batch operation with the designed PI controller, the control objective of minimizing the tracking error along both the time and batch directions is formulated based on the 2D robust H infinity control theory, such that a robust ILC updating law is determined by solving the linear matrix inequality (LMI) conditions established for holding the 2D system stability. Moreover, the batch-direction convergence rate can be separately tuned via the performance index in the above LMI conditions. An illustrative application to batch injection molding is given to demonstrate the effectiveness and merit of the proposed method.

Robust PI, gain scheduled and PSS controller design using LMI regions: Comparative studies

Abstract This paper considers development of a new design procedure for PI and Gain scheduled robust controller with PSS for turbogenerator using LMI regional regions. The obtained PI+PSS and GSC+PSS robust controllers with output and state derivative feedback for uncertain polytopic turbogenerator model ensure that all closed -loop eigenvalues lay in the prescribed LMI region. The proposed method is to guarantee the less conservativeness with respect to previous methods due to introducing a design procedure based on new auxiliary matrices. The effectiveness of this procedure is illustrated by the examples of two controllers for turbogenerator.

Analytical Design of PI Controllers for Second Order plus Time Delay Systems

Analytical design scheme of a Proportional Integral controllers for the stability and performance of second order plus time delay systems is presented in this paper. The method proposed in the study achieves general computation equations for mentioned systems. Inspired from the Bode’s ideal transfer function characteristics, gain crossover frequency and phase margin specifications are considered for the system. Then, these specifications are used to obtain the parameters of the controller. Analytically derived formulas by the proposed method are tested with existing plants in the literature and the results are illustrated graphically. It is shown that the tuning method satisfies desired gain crossover frequency and phase margin specifications.

Controller Design of UPQC for Enhancing Power Quality in Distribution System

This paper presents the procedure of PI controller design of Unified Power Quality Conditioner (UPQC) for improving power quality in the distribution system. A mathematical model of the distribution system with the UPQC is thoroughly explained in this paper. The mathematical model that is founded has been used for designing the PI controller. In order to investigate the dynamic performance and design the controller, linear approximation technique is used. Linearization of the systems that is around the operating point provides a set of linear equations, and then multi-input multi-output (MIMO) transfer functions of the systems are obtained. Two controller design techniques are presented and compared. One is the sequential loop closure controller design with parameter tuning through the Bode diagram (SLC-BD). The other one is the controller optimization design with the genetic algorithms (CO-GA). The performances of these techniques are verified and compared by using MATLAB program. Simulation results reveal that the power quality in the distribution system can be enhanced by using UPQC with the proposed controller design.

Design and Comparison of PI and Back-Stepping Control for Single Phase Two-Stage Grid Connected PV System

Design and Comparison of PI and Back-Stepping Control for Single Phase Two-Stage Grid Connected PV System

Design of fractional order 2-DOF PI controller for real-time control of heat flow experiment

This paper presents a two degree of freedom fractional order PI controller for temperature control of a real-time Heat Flow Experiment (HFE). The introduction of two degrees of freedom and fractional calculus to PI controller enhances its flexibility at the cost of large number of tuning parameters and controller design becomes a combinatorial problem. Controller parameters are therefore optimized by a meta-heuristic algorithm called as water cycle algorithm (WCA) which leads to WCA tuned two degree of freedom fractional order PI (W2FPI) controller. The present work also explores the potential of WCA as an effective controller tuning technique. The convergence analysis of WCA justifies its effectiveness with respect to state-of-the-art optimizers i.e. genetic algorithm, simulated annealing, dragonfly algorithm, flower pollination algorithm, cuckoo search algorithm, particle swarm optimization, differential evolution and artificial bee colony algorithm. Investigation reveals the superiority of W2FPI controller in comparison to its WCA tuned integer order variant W2PI and conventional PI controller.

Linear Matrix Inequality Based Synthesis of PI Controllers for PMSM with Uncertain Parameters

This paper addresses the design of robust PI controllers for permanent magnet synchronous motors in terms of a linear matrix inequality based problem. A polytopic model of the plant is obtained and validated for the motor uncertain parameters belonging to intervals. The design procedure proposed here encompasses: i. suitable plant uncertainties inclusion and the use of practical design control constraints; ii. robust PI computation based on linear matrix inequalities with a very fast solution; iii. simulation analyses; and iv. experimental evaluations. The robust PI controller can produce superior speed regulation than a PI controller designed only for the nominal parameters, including better disturbance rejection and H-infinity performance. Experimental results confirm the viability of the proposal, which can be seen as an efficient alternative to trade off performance and robustness for PI controllers in this application.