PI Fuzzy Logic Research Articles

A Fuzzy Logic PI Trajectory Following Control in a Chaotically Loaded Real Mechatronic Dynamical System with Stick-Slip Friction

Fuzzy logic control algorithms are regarded to as a relatively new concept in modern control theory. This paper presents a comparative analysis of two qualitatively different approaches used for angular velocity control of a DC motor subject to chaotic disturbances coming from a gear with a transmission belt carrying a vibrating load. The purpose is to achieve accurate control of speed of the DC motor (a plant), especially, when the motor parameters and some external loading conditions are partially unknown. First, the classical approach based on the PID control is considered, and then a fuzzy logic based alternative is proposed. Two different controllers are developed, i.e. the classical PID controller and a Mamdani type fuzzy logic PI controller. Both control algorithms are implemented on an 8-bit AVR ATmega644PA microcontroller. Based on step responses of the plant, an analysis as well as an interesting comparison of the controllers’ performance has been presented.

Design, simulation and comparative evaluation of both a classic and a fuzzy logic PI controller applied to a DC-DC converter

Design, simulation and comparative evaluation of both a classic and a fuzzy logic PI controller applied to a DC-DC converter

Controller design and stability analysis of grid connected DC microgrid

DC microgrids are desired to provide the electricity for the remote areas which are far from the main grid. The microgrid gets popularity because DC power sources such as photovoltaics (PVs), battery banks, and fuel cells can be interconnected without AC/DC converters. The stochastic nature of PV power and variation in the demand are responsible for voltage fluctuations in the DC microgrids. The voltage stability is a most important issue in the case of DC microgrids. The challenging thing is to maintain the microgrid voltage up to a reference value for the variable load. This paper focuses on designing a controller to obtain the voltage stability of the microgrid. Two controllers [PI and fuzzy logic PI (FL-PI)] are designed for the voltage stability analysis of the DC microgrid. Real-time simulation results show that upon appropriate choice of controller parameters, the DC microgrid voltage can be kept constant regardless of the wide range of voltage variations of the source and the load. The simulation results show the comparison of two controllers. The FL-PI controller shows much better performance than the conventional PI controller for the DC grid voltage control. With the inclusion of the proposed controllers, controlled voltage will be obtained, whatever may be the load and its variation.

Power quality problems mitigation using dynamic voltage restorer (DVR) with pi controller and fuzzy logic controller

The existence of non-standard currents, frequencies and voltages enhances the Power Quality (PQ) problems. Power consumed by the consumers and losses occurred in power system are deciding factors for the utility to determine the performance of the power system in terms of Power Quality. These Power Quality problems lead to failure of end user equipments as well as creates disturbances in power distribution network, thereby deteriorates residual life assessment of major equipments used in substation. The PQ problems can be characterized as voltage surges, sags, swells, harmonic distortions, etc. There are many reasons for the determination of Power Quality. The loads used by the consumers of electricity abnormally leads to deprove the Power Quality. Low power factor loads are taken care of by the utilities in the form of financial penalty. However, occurrence of harmonics, voltage swells and sags in the system is the most powerful reason behind degradation of Power Quality. To mitigate these issues, use of Custom Power Devices (CPD) in the distribution network is the most significant solution. Paper presents the design of the CPD like Dynamic Voltage Restorer (DVR) using two control strategies i.e. PI Controller and Fuzzy Logic Controller (FLC). MATLAB/SIMULINK is used to analyze the effectiveness of these control strategies.

Load frequency control of an asynchronous restructured power system: a fuzzy logic approach

This paper presents the analysis of load frequency control (LFC) of a two-area restructured power system interconnected via parallel ac/dc transmission links. Simulation results show that the limitations of PI controller can be overcome by including Fuzzy logic concept and thereby the dynamic performance can be improved substantially following a load change in any area. The dynamic responses for small perturbation have been observed with PI controller and fuzzy logic based PI controller and result of both have been compared.Keywords: Asynchronous tie-lines; Restructured power system; HVDC transmission links; Load frequency control; Fuzzy Logic based PI controller

A Comparative Strategy Using PI & Fuzzy Controller for Optimization of Power Quality Control

This paper explores the analytical study and simulation of fuzzy logic controller and PI controller, to control the dc output voltage of shunt active power filter for harmonic reduction and power quality improvement in case of nonlinear load. Here we have exercised an effort to design and evaluate a converter to compensate the harmonics for 1-phase AC to DC bridge rectifier which is working as the main converter in unregulated mode. The work depends on the scheme where an ancillary converter is linked in shunt with the main or primary converter whose turn on and turn off time is controlled by an appropriate controller (pi/fuzzy logic) for harmonic compensation of the primary converter which is working as nonlinear load. The Model of converter is proposed on MATLAB\SIMULINK Software and the results are analyzed satisfactorily.

A Comparative Strategy Using PI & Fuzzy Controller for Optimization of Power Quality Control

This paper explores the analytical study and simulation of fuzzy logic controller and PI controller, to control the dc output voltage of shunt active power filter for harmonic reduction and power quality improvement in case of nonlinear load. Here we have exercised an effort to design and evaluate a converter to compensate the harmonics for 1-phase AC to DC bridge rectifier which is working as the main converter in unregulated mode. The work depends on the scheme where an ancillary converter is linked in shunt with the main or primary converter whose turn on and turn off time is controlled by an appropriate controller (pi/fuzzy logic) for harmonic compensation of the primary converter which is working as nonlinear load. The Model of converter is proposed on MATLAB\SIMULINK Software and the results are analyzed satisfactorily.

Improved Time Responses of PI & FL Controlled SEPIC Converter based Series Resonant Inverter fed Induction Heating System

This work deals with the Power Factor Corrected Single-Ended Primary Inductor Converter (PFC-SEPIC) based voltage fed closed loop full bridge series resonant induction heating system for household induction heating applications. The output voltage of the front end PFC-SEPIC converter fed series resonant inverter governs the controllers, which may be PI controller or Fuzzy Logic Controller (FLC). The analysis and comparison of time responses are presented in this paper. The PFC-SEPIC converter is used to improve the output power and the THD of source side current are compared for PI and FLC controllers. PFC-SEPIC converter maintains improved current and voltage at unity power factor through the input mains. The SEPIC converter based Voltage Fed Full Bridge Series Resonant Inverter (VFFBSRI) converts the voltage at a frequency of 10 kHz to a level suitable for household induction heating. A 1 kW SEPIC converter based VFFBSRI with RLC load is designed and simulated using MATLAB/ Simulink and hardware is fabricated.

Design and implementation of an advanced controller in plant distributed control system for improving control of non-linear belt weigh feeder

A Belt Weigh Feeder (BWF) is a flat belt conveyor designed for feeding bulk material into a chemical process in a controlled fashion for better process control. The dynamic weight of bulk material is measured with a belt weigh bridge and the belt speed is controlled to compensate for any variation in the weight so that the mass feed rate is maintained as per the set feed rate. The problem of belt speed control is challenging as the dynamic response of system is non-linear and there are frequent changes in belt load due to variation in bulk material characteristics. The control accuracy of belt weigh feeder is fully dependent on the controller’s performance in providing precise control of speed of motor/belt. Any delay in achieving the set feed rate or frequent deviation between set and actual feed rate affects the quality and efficiency of downstream process. Conventional PI controller is unable to provide optimum control due to system non-linearity. To overcome this problem, in this paper first the operating data of the BWF system is analysed and the nature and cause for the nonlinearity is investigated. The system is then modelled using the design parameters of plant belt weigh feeder, which is then simulated to have a better insight into its non-linear response. Subsequently, based on simulation results, a PI Fuzzy Logic (PI-FL) controller is designed to improve the control accuracy of the system. Further, to ensure the stability of the system, an adaptive controller is introduced in cascade to fine tune the gains of PI-FL controller as per the operating speed of the BWF. Finally, an advanced PI-FL with cascade adaptive controller is implemented in the plant DCS (microprocessor based process control system). The actual test results indicate reduction in the Integral of Absolute Error (IAE) of the system by about 34% using this controller.

Enhanced Improvement in Dynamic Behavior of Hybrid Active Power Filter using PI Controllers and Fuzzy Logic

Enhanced Improvement in Dynamic Behavior of Hybrid Active Power Filter using PI Controllers and Fuzzy Logic

A comparative analysis of DFPI correctors and different techniques to regulate a shunt active power filter

Power quality is a subject of intense study over recent years, given that it affects the economic impact and costs of utilities, supply and manufacturing. Modern powered electronic equipment is usually nonlinear in nature and causes propagation of harmonic current. This disruptive current can be countered by various solutions, but active power filtering is the most captivating solution. In this paper, a Shunt Active Power Filter (SAPF) system is considered with a new corrector design for both the DC and AC sides. The new design is based on an association between double fuzzy logic and single PI correctors resulting in two 'DFPI' correctors devoted to regulating the DC voltage and the AC current of the SAPF. The DFPI corrector is more advantageous than the classic PI or fuzzy controllers implemented alone for regulation purposes of the SAPF control variables (DC voltage and the AC current). This is demonstrated, in this paper, through the addressed theoretical analysis of the proposed DFPI corrector and the studies shown in the simulation section comparing the proposed DFPI, single fuzzy, double fuzzy and PI controllers. Performances in terms of the filtering quality of the AC feeder side and the SAPF DC-bus voltage regulation quality (THDis%/THDVs%) are noted. The obtained numerical results prove the effectiveness of the DFPI corrector which also described a faster response time, a reduced overshoot and a lessened static error.

A Comparative Study of Fuzzy Logic Controllers for Wind Turbine Based on PMSG

This paper gives a complete design and comparative study of vector control based on Proportional Integral, fuzzy logic, and self-tuned PI by the fuzzy logic controllers of a Permanent Magnet Synchronous Generator. The direct-quadrature currents components will be controlled by the proposed controllers in order to achieve the desired performance. A complete modeling of control strategies of the overall system is presented. In order to analyze the dynamic and transient performance of the control system, some simulations are done by Matlab-Simulink.

A comparative analysis of DFPI correctors and different techniques to regulate a shunt active power filter

Power quality is a subject of intense study over recent years, given that it affects the economic impact and costs of utilities, supply and manufacturing. Modern powered electronic equipment is usually nonlinear in nature and causes propagation of harmonic current. This disruptive current can be countered by various solutions, but active power filtering is the most captivating solution. In this paper, a Shunt Active Power Filter (SAPF) system is considered with a new corrector design for both the DC and AC sides. The new design is based on an association between double fuzzy logic and single PI correctors resulting in two 'DFPI' correctors devoted to regulating the DC voltage and the AC current of the SAPF. The DFPI corrector is more advantageous than the classic PI or fuzzy controllers implemented alone for regulation purposes of the SAPF control variables (DC voltage and the AC current). This is demonstrated, in this paper, through the addressed theoretical analysis of the proposed DFPI corrector and the studies shown in the simulation section comparing the proposed DFPI, single fuzzy, double fuzzy and PI controllers. Performances in terms of the filtering quality of the AC feeder side and the SAPF DC-bus voltage regulation quality (THDis%/THDVs%) are noted. The obtained numerical results prove the effectiveness of the DFPI corrector which also described a faster response time, a reduced overshoot and a lessened static error.

Development of Power Electronic Distribution Transformer Based on Adaptive PI Controller

In recent years, power electronic distribution transformers (PEDTs) have become an attractive replacement for conventional transformers. This is due to their smaller size, improved dynamic performance, and better power quality. However, their operation with a conventional controller such as a proportional integral (PI) does not give satisfactory performance. Thus, improved dynamic performance and high power quality of the PEDT can be achieved with an intelligent control. In this paper, a novel design topology and an improved controller for a PEDT are proposed. The proposed controller is based on the adaptive PI-fuzzy logic controller (API-FLC). The FLC is applied to adapt the PI controller gains when there is a sudden change in the system parameters. The PEDT with the novel controller is designed to achieve constant dc link voltages, sinusoidal voltage, and current with unity power factor under different operating conditions. The model is simulated and validated using MATLAB/Simulink software. Different operating conditions, including voltage sag, voltage harmonics, sudden load change, and short circuit, have been investigated. The results obtained with the API-FLC controller give a better dynamic performance and improved power quality when compared to the conventional PI controller. Therefore, the PEDT based on API-FLC has the advantages of eliminating transient power quality problems and improving system efficiency.

A novel optimized hybrid fuzzy logic intelligent PID controller for an interconnected multi-area power system with physical constraints and boiler dynamics

In the fast developing world nowadays, load frequency control (LFC) is considered to be a most significant role for providing the power supply with good quality in the power system. To deliver a reliable power, LFC system requires highly competent and intelligent control technique. Hence, in this article, a novel hybrid fuzzy logic intelligent proportional-integral-derivative (FLiPID) controller has been proposed for LFC of interconnected multi-area power systems. A four-area interconnected thermal power system incorporated with physical constraints and boiler dynamics is considered and the adjustable parameters of the FLiPID controller are optimized using particle swarm optimization (PSO) scheme employing an integral square error (ISE) criterion. The proposed method has been established to enhance the power system performances as well as to reduce the oscillations of uncertainties due to variations in the system parameters and load perturbations. The supremacy of the suggested method is demonstrated by comparing the simulation results with some recently reported heuristic methods such as fuzzy logic proportional-integral (FLPI) and intelligent proportional-integral-derivative (PID) controllers for the same electrical power system. the investigations showed that the FLiPID controller provides a better dynamic performance and outperform compared to the other approaches in terms of the settling time, and minimum undershoots of the frequency as well as tie-line power flow deviations following a perturbation, in addition to perform appropriate settlement of integral absolute error (IAE). Finally, the sensitivity analysis of the plant is inspected by varying the system parameters and operating load conditions from their nominal values. It is observed that the suggested controller based optimization algorithm is robust and perform satisfactorily with the variations in operating load condition, system parameters and load pattern.

Adaptive Fuzzy Logic PI Control for Switched Reluctance Motor Based on Inductance Model

Adaptive Fuzzy Logic PI Control for Switched Reluctance Motor Based on Inductance Model

Optimized MPPT Controllers Using GA for Grid Connected Photovoltaic Systems, Comparative study

In this paper, comparisons between control strategies for grid connected photovoltaic system are proposed. MPPT algorithms P&O-PI, fuzzy logic-PI and optimized with genetic algorithm(GA) are used to control the DC/DC boost converter responsible to connect and extract the maximum power from the solar panel and transfer it to the DC-link. Another PI controller is used to maintain the DC-link voltage constant and close to its reference value under different conditions. Simulation results under different environmental and operating conditions are presented and discussed to verify the satisfactory of the performance of the proposed control strategies, in which the optimized fuzzy –PI controller by GA algorithms gives the better performance specification regarding the P&O-PI algorithm.

BRUSHLESS SPEED CONTROL WITH THE USE FUZZY LOGIC PI REGULATOR

This paper presents the fuzzy PI controllers for brushless speed control. The controller uses fuzzy logic controllers and PI controllers. The outputs of PI controllers are summarized and designated as input to the current controller. The current controller uses P controller. To simulate the proposed scheme uses the software Simulink. The results obtained for variable moment load.

Voltage Regulation Using Hybrid PI-Fuzzy Logic Controller Based Static Var Compensator for Maintaining Power Quality

Voltage Regulation Using Hybrid PI-Fuzzy Logic Controller Based Static Var Compensator for Maintaining Power Quality

Comparison Analysis of Zeta PFC Converter to Improve Power Quality Improvement by PI Controller, Hysteresis Controller and Fuzzy Logic Controller for Speed Control of Induction Motor

Comparison Analysis of Zeta PFC Converter to Improve Power Quality Improvement by PI Controller, Hysteresis Controller and Fuzzy Logic Controller for Speed Control of Induction Motor