Sy Najib Sy Salim | Universiti Teknikal Malaysia Melaka (original) (raw)

Papers by Sy Najib Sy Salim

2016 IEEE Conference on Systems, Process and Control (ICSPC), 2016

This paper presents the potential of the Model Reference Adaptive Control (MRAC) and Proportional... more This paper presents the potential of the Model Reference Adaptive Control (MRAC) and Proportional-Integral (PI) controller in improving the tracking performance and transient response of XY Table Ball Screw Driven System. The technique used to design MRAC controller is based on Lyapunov approach that is taken to account the stability of the system. Simulation and experimental test are conducted with two different inputs namely step and sinusoidal to evaluate the performance of this technique. The tracking performance is evaluated based on maximum tracking error and root mean square error (RMSE). In addition, the transient response properties are also evaluated. The results of the comparison between these two techniques are compared and presented.

Controlling Uncertainty, 2010

Journal of Telecommunication, Electronic and Computer Engineering, 2017

In this article, a precise positioning control strategy for the nonlinearity of machine tools is ... more In this article, a precise positioning control strategy for the nonlinearity of machine tools is thoroughly reviewed. Precise positioning is crucial in machine tools industry where nonlinear phenomenon must be considered. Therefore, this paper aims to review various techniques used to enhance the precision of nonlinearity of machine tools. In the introduction, a significant review of machine tools is discussed based on deadzone phenomenon and high bandwidth. After that, linear control strategies are reviewed involving Proportional-Integral-Derivative (PID) and Cascade P/PI controller. This is followed by nonlinear control strategies, Nonlinear PID (NPID), Adaptive NPID (ANPID), Feedforward NPID (FNPID), Adaptive Robust Controller (ARC), Nominal Characteristics Trajectory Following (NCTF) controller and lastly, the fuzzy and neural network control is then reviewed. Finally, conclusions are presented according to the past researches conducted. Further studies regarding the topic can b...

Lecture Notes in Electrical Engineering, 2019

In this paper, an evaluation of Nonlinear Proportional Integral (NPI) Double Hyperbolic controlle... more In this paper, an evaluation of Nonlinear Proportional Integral (NPI) Double Hyperbolic controller, which is tested on a pneumatic actuator system is performed. The NPI Double Hyperbolic controller consists of two nonlinear functions that are added before proportional and integral gains. These functions are named as nonlinear proportional and nonlinear integral, in which they are embedded with a hyperbolic function. This controller scheme is designed via MATLAB/Simulink software and it is run four times for simulation and experimental work. The scheme of this controller includes the system’s mathematical model, which is obtained by estimating model using System Identification Toolbox in MATLAB. In addition, the simulation and experimental works are tested using the step input. The performance of the proposed technique is compared between PI and NPI Double Hyperbolic controller based on the rise time and overshoot. The results show that the NPI Double Hyperbolic has better transient performance with smaller rise time and smaller overshoot via experimental work compared to the conventional PI controller.

JOURNAL OF MECHANICAL ENGINEERING AND SCIENCES, 2017

The high demand in tracking performance is crucial in machine tools application. Therefore, the p... more The high demand in tracking performance is crucial in machine tools application. Therefore, the purpose of this paper is to design a Nonlinear PID (NPID) controller for improvement of tracking performance via cutting force. The method was then compared with another method which was conventional PID controller. The configuration included different cutting force disturbances of 1500rpm, 2500rpm and 3500rpm. The parameters were set to 0.4Hz and 0.7Hz frequency for every 10mm and 20mm of amplitude, respectively. The investigation was centred on a comparative study of these two techniques which focused on x-axis of Googol Tech XY ball screw drive system. Results between the designed controllers were validated based on two types of errors; the maximum tracking error and root mean square error. Results showed that the NPID controller recorded better tracking performance compared to PID controller with an error reduction of about 33%. In addition, the results proved that NPID controller is highly practical and suitable to be used for ball screw drive. The controller can be further improved with the implementation of observer such as disturbance observer to compensate the cutting forces.

Proceeding of the Electrical Engineering Computer Science and Informatics, 2014

In psychology or educational research, we often want to test the validity of our instrument. Usua... more In psychology or educational research, we often want to test the validity of our instrument. Usually we use the Pearson coefficient of correlation in validity testing. However, the distribution of the data are not always normal distribution so it is also possible to use the Spearman and Kendall coefficient of correlation to test the validity of items. Valid items tend to have a positive and significant coefficient of correlation. It means the item is likely to be answered correctly by people who have a high total score and tend to be answered incorrectly by people who have a low total score. Item discrimination index is an index that measures the ability of item to be able to discriminate students who have high learning outcomes and students who have low learning outcomes. Simulation studies provide a clearer description and show that the item discrimination index has a significant relationship to validity testing that is commonly used in research.

TELKOMNIKA (Telecommunication Computing Electronics and Control), 2020

A pneumatic actuator is a device that converts compressed air into mechanical energy to perform v... more A pneumatic actuator is a device that converts compressed air into mechanical energy to perform varieties of work. It exhibits high nonlinearities due to high friction forces, compressibility of air and dead band of the spool movement which is difficult to manage and requires an appropriate controller for better performance. The purpose of this study is to review the controller design of pneumatic actuator recommended by previous researchers from the past years. Initially, the basic views of the pneumatic will be presented in terms of introduction to the pneumatic actuator and its applications in industries. At the end of this review, discussions on the design of the controllers will be concluded and further research will be proposed along with the improvement of control strategies in the pneumatic actuator systems.

International Journal of Electrical and Computer Engineering (IJECE), 2017

This paper demonstrates the effectiveness of applying constraints in a controller algorithm as a ... more This paper demonstrates the effectiveness of applying constraints in a controller algorithm as a strategy to enhance the pneumatic actuator system’s positioning performance. The aim of the present study is to reduce the overshoot in the pneumatic actuator positioning system’s response. An autoregressive with exogenous input (ARX) model structure has been used to model the pneumatic system, while a model predictive control (MPC) has been employed as a control strategy. The input constraint has been applied to the control signals (on/off valves signals) to ensure accurate position tracking. Results show that the strategy with constraint effectively reduced overshoot by more than 99.0837 % and 97.0596 % in simulation and real-time experiments, respectively. Moreover, the performance of the proposed strategy in controlling the pneumatic positioning system is considered good enough under various loads. The proposed strategy can be applied in any industry that used pneumatic actuator in t...

International Journal of Electrical and Computer Engineering (IJECE), 2019

The present article describes the improvement of Self-regulation Nonlinear PID (SN-PID) controlle... more The present article describes the improvement of Self-regulation Nonlinear PID (SN-PID) controller. A new function is introduced to improve the system performance in terms of transient without affecting the steady state performance. It is used to optimize the nonlinear function available on this controller. The signal error is reprocessed through this function, and the result is used to tune the nonlinear function of the controller. Furthermore, the presence of the dead zone on the proportional valve is solved using Dead Zone Compensator (DZC). Simulations and experiments were carried out on the pneumatic positioning system. Comparisons between the existing methods were examined and successfully demonstrated.

IFAC-PapersOnLine, 2019

The paper deals with the control of a wastewater treatment plant designed for a 250,000 inhabitan... more The paper deals with the control of a wastewater treatment plant designed for a 250,000 inhabitants city. In order to developed different control strategies a specific influent was defined. It is the influent from BSM1 calibrated according to the real data of the wastewaters collected from the wastewater treatment plant. Five control strategies were developed based on conventional controllers and compared to each other using the quality indicators specific to the wastewater treatment domain. Finally, an optimal setpoint-based control method has been developed which takes into consideration a criterion based on two very important factors in the case of a large-capacity wastewater treatment plant: the cost of the biological treatment and the effluent quality.

International Journal on Advanced Science, Engineering and Information Technology, 2017

An Intelligent Pneumatic Actuator (IPA) system is considered highly nonlinear and subject to nonl... more An Intelligent Pneumatic Actuator (IPA) system is considered highly nonlinear and subject to nonlinearities which make the precise position control of this actuator is difficult to achieve. Thus, it is appropriate to model the system using nonlinear approach because the linear model sometimes not sufficient enough to represent the nonlinearity of the system in the real process. This study presents a new modeling of an IPA system using Hammerstein model based Recursive Least Square (RLS) algorithm. The Hammerstein model is one of the blocks structured nonlinear models often used to model a nonlinear system and it consists of a static nonlinear block followed by a linear block of dynamic element. In this study, the static nonlinear block was represented by a deadzone of the pneumatic valve, while the linear block was represented by a dynamic element of IPA system. A RLS has been employed as the main algorithm in order to estimate the parameters of the Hammerstein model. The validity of the proposed model has been verified by conducting a real-time experiment. All of the criteria as outlined in the system identification's procedures were successfully complied by the proposed Hammerstein model as it managed to provide a stable system, higher best fit, lower loss function and lower final prediction error than a linear model developed before. The performance of the proposed Hammerstein model in controlling the IPA's positioning system is also considered good. Thus, this new developed Hammerstein model is sufficient enough to represents the IPA system utilized in this study.

International Review of Automatic Control (IREACO), 2016

This paper describes the potential of the fuzzy logic technique and cascade controller in improvi... more This paper describes the potential of the fuzzy logic technique and cascade controller in improving the tracking performance of the XY Table Ball Screw Driven System. The proposed controller used in this research is Cascade Fuzzy P+PI. This proposed technique is compared to other techniques, namely PI and Fuzzy-PI controllers, for the purpose of proving the ability of both techniques in producing good results. The performances of the systems are analyzed to two cases, with and without disturbance. The disturbance case involves the form of cutting force with different spindle speeds which are 1000 rpm, 2000 rpm, and 3000 rpm. Besides, in order to examine robustness, the system is operated under different frequencies of 0.3 Hz, 0.5 Hz, and 0.7 Hz. The results show that the combination of Fuzzy Logic technique with Cascade Controller, which is known as Cascade Fuzzy P+PI, successfully, provide a good performance with an increase of 55% to 71% compared to other methods tested in this research.

International Review of Automatic Control (IREACO), 2016

Instability may cause a system to move dangerously and suffer bodily damage, which can become cos... more Instability may cause a system to move dangerously and suffer bodily damage, which can become costly. One of the reasons for designing control systems is to stabilize an unstable system. However, control of unstable systems is primarily more difficult either due to lack of precise description of the system or incompletely modelled disturbances. Application of a classical control algorithm does not mostly yield the desired results. Advanced control is expensive and intelligent control has parameters' choice/tuning issues. This paper presents a comparison of optimal Proportional Integral Derivative (PID) controller design techniques for an inverted pendulum. The optimization approaches considered are the swarm intelligent based algorithm (Particle Swarm Optimization [PSO]) and Enhanced Nonlinear PID (EN-PID). The performances of the controllers were evaluated based on stabilizing the angle of the pendulum and disturbance rejection. Simulation results revealed that the PSO-PID outperformed the EN-PID and PID in maintaining the pendulum vertically and demonstrated an attractive ability in rejecting disturbances as compared to the PID and EN-PID. The PSO-PID may serve as a useful control algorithm for the system.

Arabian Journal for Science and Engineering, 2014

Wastewater treatment plant is a large-scale system and highly known with the nonlinearity of the ... more Wastewater treatment plant is a large-scale system and highly known with the nonlinearity of the parameters, making them a challenge to be controlled. In this paper, enhanced nonlinear PI (EN-PI) controller is developed for activated sludge process where a sector-bounded nonlinear gain with automatic gain adjustment is cascaded to conventional static-gain PI. The importance in controlling the dissolved oxygen concentration and the improvement of nitrogen removal process are discussed. The effectiveness of the proposed EN-PI controller is validated by comparing the performance of local control loops and the activated sludge process to the benchmark PI under three different weathers. The EN-PI controller is effectively applied in improving the performances of the static-gain PI, hence controlling the dynamic natures of the plant. It was proved by significant improvement in effluent violations, effluent quality index and energy saving of the Benchmark Simulation Model No.1.

This paper depicts the development of real time motor drive system. The modeling of Direct Curren... more This paper depicts the development of real time motor drive system. The modeling of Direct Current (DC) motor is vital in this work and hence is discussed in brief. Experimental setup consists of DC motor, rotary encoder, interface card and personal computer is thoroughly configured to obtain useful data such as control signal, speed and position of the motor. User interface and control algorithm is developed using Microsoft Visual C#. Proportional-Integral (PI) algorithm is developed to perform cascaded control of the DC motor. The system equipped with fixed inner current loop control parameters while the outer speed and position loop is varied to obtain the most satisfied position and speed of such motor. Through comparison of demanded speed and position, literal analysis of real time speed and position is thoroughly discussed.

International Journal of Electrical and Computer Engineering (IJECE), 2014

This paper presents the pneumatic positioning system controlled by Enhanced Nonlinear PID (NPID) ... more This paper presents the pneumatic positioning system controlled by Enhanced Nonlinear PID (NPID) controller. The characteristic of rate variation of the nonlinear gain that are readily available in NPID controller is utilized to improve the performance of the controller. A Self-regulation Nonlinear Function (SNF) is used to reprocess the error signals with the purpose of continuously generating the values for the rate variation. Subsequently, the controller has successfully been implemented on dynamically changing loads and pressures. The comparison with the other available method such as. NPID and conventional PID are performed and evaluated. The effectiveness of this method with Dead Zone Compensator (DZC) has also been successfully demonstrated and proven through simulations and experimental studies.

Pneumatic actuator system is inexpensive, high power to weight ratio, cleanliness and ease of mai... more Pneumatic actuator system is inexpensive, high power to weight ratio, cleanliness and ease of maintenance make it's a choice compared to hydraulic actuator and electromagnetic actuator. Nonetheless, the steady state error of the system is high due to the dead zone of the valve. In this paper, an Auto-Regressive with External Input (ARX) model structure is chosen to represent the pneumatic actuator system. The recursive least square method is used to estimate the model parameters. The poleassignment controller is then developed for position tracking. To cater the problem of high in steady state error, the dead zone compensation is added to the system. The dead zone controller was designed based on the inverse dead zone model and the dead zone compensation designed based on the desired error. The proposed method is then experimentally with varies load and compares with Nonlinear PID

Proceedings - 2013 IEEE 3rd International Conference on System Engineering and Technology, ICSET 2013, 2013

ABSTRACT

2016 IEEE Conference on Systems, Process and Control (ICSPC), 2016

This paper presents the potential of the Model Reference Adaptive Control (MRAC) and Proportional... more This paper presents the potential of the Model Reference Adaptive Control (MRAC) and Proportional-Integral (PI) controller in improving the tracking performance and transient response of XY Table Ball Screw Driven System. The technique used to design MRAC controller is based on Lyapunov approach that is taken to account the stability of the system. Simulation and experimental test are conducted with two different inputs namely step and sinusoidal to evaluate the performance of this technique. The tracking performance is evaluated based on maximum tracking error and root mean square error (RMSE). In addition, the transient response properties are also evaluated. The results of the comparison between these two techniques are compared and presented.

Controlling Uncertainty, 2010

Journal of Telecommunication, Electronic and Computer Engineering, 2017

In this article, a precise positioning control strategy for the nonlinearity of machine tools is ... more In this article, a precise positioning control strategy for the nonlinearity of machine tools is thoroughly reviewed. Precise positioning is crucial in machine tools industry where nonlinear phenomenon must be considered. Therefore, this paper aims to review various techniques used to enhance the precision of nonlinearity of machine tools. In the introduction, a significant review of machine tools is discussed based on deadzone phenomenon and high bandwidth. After that, linear control strategies are reviewed involving Proportional-Integral-Derivative (PID) and Cascade P/PI controller. This is followed by nonlinear control strategies, Nonlinear PID (NPID), Adaptive NPID (ANPID), Feedforward NPID (FNPID), Adaptive Robust Controller (ARC), Nominal Characteristics Trajectory Following (NCTF) controller and lastly, the fuzzy and neural network control is then reviewed. Finally, conclusions are presented according to the past researches conducted. Further studies regarding the topic can b...

Lecture Notes in Electrical Engineering, 2019

In this paper, an evaluation of Nonlinear Proportional Integral (NPI) Double Hyperbolic controlle... more In this paper, an evaluation of Nonlinear Proportional Integral (NPI) Double Hyperbolic controller, which is tested on a pneumatic actuator system is performed. The NPI Double Hyperbolic controller consists of two nonlinear functions that are added before proportional and integral gains. These functions are named as nonlinear proportional and nonlinear integral, in which they are embedded with a hyperbolic function. This controller scheme is designed via MATLAB/Simulink software and it is run four times for simulation and experimental work. The scheme of this controller includes the system’s mathematical model, which is obtained by estimating model using System Identification Toolbox in MATLAB. In addition, the simulation and experimental works are tested using the step input. The performance of the proposed technique is compared between PI and NPI Double Hyperbolic controller based on the rise time and overshoot. The results show that the NPI Double Hyperbolic has better transient performance with smaller rise time and smaller overshoot via experimental work compared to the conventional PI controller.

JOURNAL OF MECHANICAL ENGINEERING AND SCIENCES, 2017

The high demand in tracking performance is crucial in machine tools application. Therefore, the p... more The high demand in tracking performance is crucial in machine tools application. Therefore, the purpose of this paper is to design a Nonlinear PID (NPID) controller for improvement of tracking performance via cutting force. The method was then compared with another method which was conventional PID controller. The configuration included different cutting force disturbances of 1500rpm, 2500rpm and 3500rpm. The parameters were set to 0.4Hz and 0.7Hz frequency for every 10mm and 20mm of amplitude, respectively. The investigation was centred on a comparative study of these two techniques which focused on x-axis of Googol Tech XY ball screw drive system. Results between the designed controllers were validated based on two types of errors; the maximum tracking error and root mean square error. Results showed that the NPID controller recorded better tracking performance compared to PID controller with an error reduction of about 33%. In addition, the results proved that NPID controller is highly practical and suitable to be used for ball screw drive. The controller can be further improved with the implementation of observer such as disturbance observer to compensate the cutting forces.

Proceeding of the Electrical Engineering Computer Science and Informatics, 2014

In psychology or educational research, we often want to test the validity of our instrument. Usua... more In psychology or educational research, we often want to test the validity of our instrument. Usually we use the Pearson coefficient of correlation in validity testing. However, the distribution of the data are not always normal distribution so it is also possible to use the Spearman and Kendall coefficient of correlation to test the validity of items. Valid items tend to have a positive and significant coefficient of correlation. It means the item is likely to be answered correctly by people who have a high total score and tend to be answered incorrectly by people who have a low total score. Item discrimination index is an index that measures the ability of item to be able to discriminate students who have high learning outcomes and students who have low learning outcomes. Simulation studies provide a clearer description and show that the item discrimination index has a significant relationship to validity testing that is commonly used in research.

TELKOMNIKA (Telecommunication Computing Electronics and Control), 2020

A pneumatic actuator is a device that converts compressed air into mechanical energy to perform v... more A pneumatic actuator is a device that converts compressed air into mechanical energy to perform varieties of work. It exhibits high nonlinearities due to high friction forces, compressibility of air and dead band of the spool movement which is difficult to manage and requires an appropriate controller for better performance. The purpose of this study is to review the controller design of pneumatic actuator recommended by previous researchers from the past years. Initially, the basic views of the pneumatic will be presented in terms of introduction to the pneumatic actuator and its applications in industries. At the end of this review, discussions on the design of the controllers will be concluded and further research will be proposed along with the improvement of control strategies in the pneumatic actuator systems.

International Journal of Electrical and Computer Engineering (IJECE), 2017

This paper demonstrates the effectiveness of applying constraints in a controller algorithm as a ... more This paper demonstrates the effectiveness of applying constraints in a controller algorithm as a strategy to enhance the pneumatic actuator system’s positioning performance. The aim of the present study is to reduce the overshoot in the pneumatic actuator positioning system’s response. An autoregressive with exogenous input (ARX) model structure has been used to model the pneumatic system, while a model predictive control (MPC) has been employed as a control strategy. The input constraint has been applied to the control signals (on/off valves signals) to ensure accurate position tracking. Results show that the strategy with constraint effectively reduced overshoot by more than 99.0837 % and 97.0596 % in simulation and real-time experiments, respectively. Moreover, the performance of the proposed strategy in controlling the pneumatic positioning system is considered good enough under various loads. The proposed strategy can be applied in any industry that used pneumatic actuator in t...

International Journal of Electrical and Computer Engineering (IJECE), 2019

The present article describes the improvement of Self-regulation Nonlinear PID (SN-PID) controlle... more The present article describes the improvement of Self-regulation Nonlinear PID (SN-PID) controller. A new function is introduced to improve the system performance in terms of transient without affecting the steady state performance. It is used to optimize the nonlinear function available on this controller. The signal error is reprocessed through this function, and the result is used to tune the nonlinear function of the controller. Furthermore, the presence of the dead zone on the proportional valve is solved using Dead Zone Compensator (DZC). Simulations and experiments were carried out on the pneumatic positioning system. Comparisons between the existing methods were examined and successfully demonstrated.

IFAC-PapersOnLine, 2019

The paper deals with the control of a wastewater treatment plant designed for a 250,000 inhabitan... more The paper deals with the control of a wastewater treatment plant designed for a 250,000 inhabitants city. In order to developed different control strategies a specific influent was defined. It is the influent from BSM1 calibrated according to the real data of the wastewaters collected from the wastewater treatment plant. Five control strategies were developed based on conventional controllers and compared to each other using the quality indicators specific to the wastewater treatment domain. Finally, an optimal setpoint-based control method has been developed which takes into consideration a criterion based on two very important factors in the case of a large-capacity wastewater treatment plant: the cost of the biological treatment and the effluent quality.

International Journal on Advanced Science, Engineering and Information Technology, 2017

An Intelligent Pneumatic Actuator (IPA) system is considered highly nonlinear and subject to nonl... more An Intelligent Pneumatic Actuator (IPA) system is considered highly nonlinear and subject to nonlinearities which make the precise position control of this actuator is difficult to achieve. Thus, it is appropriate to model the system using nonlinear approach because the linear model sometimes not sufficient enough to represent the nonlinearity of the system in the real process. This study presents a new modeling of an IPA system using Hammerstein model based Recursive Least Square (RLS) algorithm. The Hammerstein model is one of the blocks structured nonlinear models often used to model a nonlinear system and it consists of a static nonlinear block followed by a linear block of dynamic element. In this study, the static nonlinear block was represented by a deadzone of the pneumatic valve, while the linear block was represented by a dynamic element of IPA system. A RLS has been employed as the main algorithm in order to estimate the parameters of the Hammerstein model. The validity of the proposed model has been verified by conducting a real-time experiment. All of the criteria as outlined in the system identification's procedures were successfully complied by the proposed Hammerstein model as it managed to provide a stable system, higher best fit, lower loss function and lower final prediction error than a linear model developed before. The performance of the proposed Hammerstein model in controlling the IPA's positioning system is also considered good. Thus, this new developed Hammerstein model is sufficient enough to represents the IPA system utilized in this study.

International Review of Automatic Control (IREACO), 2016

This paper describes the potential of the fuzzy logic technique and cascade controller in improvi... more This paper describes the potential of the fuzzy logic technique and cascade controller in improving the tracking performance of the XY Table Ball Screw Driven System. The proposed controller used in this research is Cascade Fuzzy P+PI. This proposed technique is compared to other techniques, namely PI and Fuzzy-PI controllers, for the purpose of proving the ability of both techniques in producing good results. The performances of the systems are analyzed to two cases, with and without disturbance. The disturbance case involves the form of cutting force with different spindle speeds which are 1000 rpm, 2000 rpm, and 3000 rpm. Besides, in order to examine robustness, the system is operated under different frequencies of 0.3 Hz, 0.5 Hz, and 0.7 Hz. The results show that the combination of Fuzzy Logic technique with Cascade Controller, which is known as Cascade Fuzzy P+PI, successfully, provide a good performance with an increase of 55% to 71% compared to other methods tested in this research.

International Review of Automatic Control (IREACO), 2016

Instability may cause a system to move dangerously and suffer bodily damage, which can become cos... more Instability may cause a system to move dangerously and suffer bodily damage, which can become costly. One of the reasons for designing control systems is to stabilize an unstable system. However, control of unstable systems is primarily more difficult either due to lack of precise description of the system or incompletely modelled disturbances. Application of a classical control algorithm does not mostly yield the desired results. Advanced control is expensive and intelligent control has parameters' choice/tuning issues. This paper presents a comparison of optimal Proportional Integral Derivative (PID) controller design techniques for an inverted pendulum. The optimization approaches considered are the swarm intelligent based algorithm (Particle Swarm Optimization [PSO]) and Enhanced Nonlinear PID (EN-PID). The performances of the controllers were evaluated based on stabilizing the angle of the pendulum and disturbance rejection. Simulation results revealed that the PSO-PID outperformed the EN-PID and PID in maintaining the pendulum vertically and demonstrated an attractive ability in rejecting disturbances as compared to the PID and EN-PID. The PSO-PID may serve as a useful control algorithm for the system.

Arabian Journal for Science and Engineering, 2014

Wastewater treatment plant is a large-scale system and highly known with the nonlinearity of the ... more Wastewater treatment plant is a large-scale system and highly known with the nonlinearity of the parameters, making them a challenge to be controlled. In this paper, enhanced nonlinear PI (EN-PI) controller is developed for activated sludge process where a sector-bounded nonlinear gain with automatic gain adjustment is cascaded to conventional static-gain PI. The importance in controlling the dissolved oxygen concentration and the improvement of nitrogen removal process are discussed. The effectiveness of the proposed EN-PI controller is validated by comparing the performance of local control loops and the activated sludge process to the benchmark PI under three different weathers. The EN-PI controller is effectively applied in improving the performances of the static-gain PI, hence controlling the dynamic natures of the plant. It was proved by significant improvement in effluent violations, effluent quality index and energy saving of the Benchmark Simulation Model No.1.

This paper depicts the development of real time motor drive system. The modeling of Direct Curren... more This paper depicts the development of real time motor drive system. The modeling of Direct Current (DC) motor is vital in this work and hence is discussed in brief. Experimental setup consists of DC motor, rotary encoder, interface card and personal computer is thoroughly configured to obtain useful data such as control signal, speed and position of the motor. User interface and control algorithm is developed using Microsoft Visual C#. Proportional-Integral (PI) algorithm is developed to perform cascaded control of the DC motor. The system equipped with fixed inner current loop control parameters while the outer speed and position loop is varied to obtain the most satisfied position and speed of such motor. Through comparison of demanded speed and position, literal analysis of real time speed and position is thoroughly discussed.

International Journal of Electrical and Computer Engineering (IJECE), 2014

This paper presents the pneumatic positioning system controlled by Enhanced Nonlinear PID (NPID) ... more This paper presents the pneumatic positioning system controlled by Enhanced Nonlinear PID (NPID) controller. The characteristic of rate variation of the nonlinear gain that are readily available in NPID controller is utilized to improve the performance of the controller. A Self-regulation Nonlinear Function (SNF) is used to reprocess the error signals with the purpose of continuously generating the values for the rate variation. Subsequently, the controller has successfully been implemented on dynamically changing loads and pressures. The comparison with the other available method such as. NPID and conventional PID are performed and evaluated. The effectiveness of this method with Dead Zone Compensator (DZC) has also been successfully demonstrated and proven through simulations and experimental studies.

Pneumatic actuator system is inexpensive, high power to weight ratio, cleanliness and ease of mai... more Pneumatic actuator system is inexpensive, high power to weight ratio, cleanliness and ease of maintenance make it's a choice compared to hydraulic actuator and electromagnetic actuator. Nonetheless, the steady state error of the system is high due to the dead zone of the valve. In this paper, an Auto-Regressive with External Input (ARX) model structure is chosen to represent the pneumatic actuator system. The recursive least square method is used to estimate the model parameters. The poleassignment controller is then developed for position tracking. To cater the problem of high in steady state error, the dead zone compensation is added to the system. The dead zone controller was designed based on the inverse dead zone model and the dead zone compensation designed based on the desired error. The proposed method is then experimentally with varies load and compares with Nonlinear PID

Proceedings - 2013 IEEE 3rd International Conference on System Engineering and Technology, ICSET 2013, 2013

ABSTRACT