Abstract In general two basic methods are used for controlling the velocity of a hydraulic cylinder. First by an axial variable-displacement pump for controls flow to the cylinder. This configuration is commonly known as a hydrostatic transmission. Second by proportional valve powered by a constant-pressure source, such as a pressure compensated pump, drives the hydraulic cylinder. In this study, the electro-hydraulic servo system (EHSS) for velocity control of hydraulic cylinder is investigated experimentally and its analysis theoretically. Where the controlled hydraulic cylinder is altered by a swashplate axial piston pump or by proportional valve to achieve velocity control. The theoretical part includes the derivation of the mathematical model equations of combination system. Velocity control system for hydraulic cylinder using simple (PID) controller to get constant velocity range of hydraulic cylinder under applied external variable loads . An experimental set-up is constructed, which consists of the hydraulic test pump unit, the electro-hydraulic proportional valve unit, the hydraulic actuator unit , the external load control unit and interfacing electronic unit. The experimental results show that PID controller can be achieve good velocity control by variable displacement axial piston pump and also by proportional valve under external loads variations. Keywords: Velocity control, Swashplate, Proportional valve, Hydraulic cylinder, PID controller, Axial piston pump
This paper describes the design and the simulation of a non-linear controller for two-mass system using induction motor basing on the backstepping method. The aim is to control the speed actual value of load motor matching with the speed reference load motor, moreover, electrical drive’s respone ensuring the “fast, accurate and small overshoot” and reducing the resonance oscillations for two-mass system using induction motor fed by voltage source inveter with ideally control performance of stator current. Backstepping controller uses the non-linear equations of an induction motor and the linear dynamical equations of two-mass system, the Lyapunov analysis and the errors between the real and the desired values. The controller has been implemented in both simulation and hardware-in-the-loop (HIL) real-time experiments using Typhoon HIL 402 system, when the drive system operates at a stable speed (rotor flux is constant) and greater than rated speed (field weakening area). The simulation and HIL results presented the correctness and effectiveness of the controller is proposed; furthermore, compared to PI method to see the response of the system clearly.
Comparative Performance Study for Closed Loop Operation of an Adjustable Spee...IJPEDS-IAES
In this paper an extensive comparative study is carried out between PI
and PID controlled closed loop model of an adjustable speed Permanent
Magnet Synchronous Motor (PMSM) drive. The incorporation of Sinusoidal
Pulse Width Modulation (SPWM) strategy establishes near sinusoidal
armature phase currents and comparatively less torque ripples without
sacrificing torque/weight ratio. In this closed loop model of PMSM drive, the
information about reference speed is provided to a speed controller, to ensure
that actual drive speed tracks the reference speed with ideally zero steady
state speed error. The entire model of PMSM closed loop drive is divided
into two loops, inner loop current and outer loop speed. By taking the
different combinations of two classical controllers (PI & PID) related with
two loop control structure, different approximations are carried out. Hence a
typical comparative study is introduced to familiar with the different
performance indices of the system corresponding to time domain and
frequency domain specifications. Therefore overall performance of closed
loop PMSM drive is tested and effectiveness of controllers will be
determined for different combinations.
In recent advancements in electric machine and drives, wound rotor motor is extensively used. The merit of using wound rotor induction motor is to control speed/torque characteristics by inserting external resistance. Wound rotor induction motor can be used in the cases such as (a) low inrush current, (b) load requiring high starting torque, (c) lower starting current is required, (d) loads having high inertia, and (e) gradual built up of torque. Examples include conveyers, cranes, pumps, elevators, and compressors. This paper includes speed control of wound induction motor using MATLAB/Simulink for rotor resistance and slip power recovery method. The characteristics of these speed control methods are hence analysed.
Experimental study of the forces above and under the vibration insulators of ...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Experimental study of the forces above and under the vibration insulators of ...eSAT Journals
Abstract This paper presents an established measuring system of the forces above and under the vibration insulators of the unit with a four-cylinder diesel engine and electric generator. Here are presented the components of the measurement system and the methodology created for measurements of bearings reactions above and under the elastic suspension elements of the unit, in a vertical direction, in which the data for the measured value is stored, processed and visualized in a MATLAB environment. The results that were obtained from the measurements of the forces above and under the four vibration insulators of the diesel generator are analyzed and graphically presented in this paper, as a function of the time at the transitional modes: starting, stopping, uploading and downloading with electrical load. The results that were obtained from measurements of the forces above and under the four vibration insulators of the diesel generator and per one working cycle of the diesel engine are presented and analyzed in this paper, as a function of the angle of rotation of the crankshaft at full load (maximum electrical load) and at idle running (without electrical load). With the thus created measurement system and methodology, scientific and applied researches can be conducted, in order to determine the quality of the vibration insulation of machine units with internal combustion engines. Keywords: Internal combustion engines, diesel generator, measuring, experimental study.
Nonlinear control of WECS based on PMSG for optimal power extraction IJECEIAES
This paper proposes a robust control strategy for optimizing the maximum power captured in Wind Energy Conversion Systems (WECS) based on permanent magnet synchronous generators (PMSG), which is integrated into the grid. In order to achieve the maximum power point (MPPT) the machine side converter regulates the rotational speed of the PMSG to track the optimal speed. To evaluate the performance and effectiveness of the proposed controller, a comparative study between the IBC control and the vector control based on PI controller was carried out through computer simulation. This analysis consists of two case studies including stochastic variation in wind speed and step change in wind speed.
This paper describes the design and the simulation of a non-linear controller for two-mass system using induction motor basing on the backstepping method. The aim is to control the speed actual value of load motor matching with the speed reference load motor, moreover, electrical drive’s respone ensuring the “fast, accurate and small overshoot” and reducing the resonance oscillations for two-mass system using induction motor fed by voltage source inveter with ideally control performance of stator current. Backstepping controller uses the non-linear equations of an induction motor and the linear dynamical equations of two-mass system, the Lyapunov analysis and the errors between the real and the desired values. The controller has been implemented in both simulation and hardware-in-the-loop (HIL) real-time experiments using Typhoon HIL 402 system, when the drive system operates at a stable speed (rotor flux is constant) and greater than rated speed (field weakening area). The simulation and HIL results presented the correctness and effectiveness of the controller is proposed; furthermore, compared to PI method to see the response of the system clearly.
Comparative Performance Study for Closed Loop Operation of an Adjustable Spee...IJPEDS-IAES
In this paper an extensive comparative study is carried out between PI
and PID controlled closed loop model of an adjustable speed Permanent
Magnet Synchronous Motor (PMSM) drive. The incorporation of Sinusoidal
Pulse Width Modulation (SPWM) strategy establishes near sinusoidal
armature phase currents and comparatively less torque ripples without
sacrificing torque/weight ratio. In this closed loop model of PMSM drive, the
information about reference speed is provided to a speed controller, to ensure
that actual drive speed tracks the reference speed with ideally zero steady
state speed error. The entire model of PMSM closed loop drive is divided
into two loops, inner loop current and outer loop speed. By taking the
different combinations of two classical controllers (PI & PID) related with
two loop control structure, different approximations are carried out. Hence a
typical comparative study is introduced to familiar with the different
performance indices of the system corresponding to time domain and
frequency domain specifications. Therefore overall performance of closed
loop PMSM drive is tested and effectiveness of controllers will be
determined for different combinations.
In recent advancements in electric machine and drives, wound rotor motor is extensively used. The merit of using wound rotor induction motor is to control speed/torque characteristics by inserting external resistance. Wound rotor induction motor can be used in the cases such as (a) low inrush current, (b) load requiring high starting torque, (c) lower starting current is required, (d) loads having high inertia, and (e) gradual built up of torque. Examples include conveyers, cranes, pumps, elevators, and compressors. This paper includes speed control of wound induction motor using MATLAB/Simulink for rotor resistance and slip power recovery method. The characteristics of these speed control methods are hence analysed.
Experimental study of the forces above and under the vibration insulators of ...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Experimental study of the forces above and under the vibration insulators of ...eSAT Journals
Abstract This paper presents an established measuring system of the forces above and under the vibration insulators of the unit with a four-cylinder diesel engine and electric generator. Here are presented the components of the measurement system and the methodology created for measurements of bearings reactions above and under the elastic suspension elements of the unit, in a vertical direction, in which the data for the measured value is stored, processed and visualized in a MATLAB environment. The results that were obtained from the measurements of the forces above and under the four vibration insulators of the diesel generator are analyzed and graphically presented in this paper, as a function of the time at the transitional modes: starting, stopping, uploading and downloading with electrical load. The results that were obtained from measurements of the forces above and under the four vibration insulators of the diesel generator and per one working cycle of the diesel engine are presented and analyzed in this paper, as a function of the angle of rotation of the crankshaft at full load (maximum electrical load) and at idle running (without electrical load). With the thus created measurement system and methodology, scientific and applied researches can be conducted, in order to determine the quality of the vibration insulation of machine units with internal combustion engines. Keywords: Internal combustion engines, diesel generator, measuring, experimental study.
Nonlinear control of WECS based on PMSG for optimal power extraction IJECEIAES
This paper proposes a robust control strategy for optimizing the maximum power captured in Wind Energy Conversion Systems (WECS) based on permanent magnet synchronous generators (PMSG), which is integrated into the grid. In order to achieve the maximum power point (MPPT) the machine side converter regulates the rotational speed of the PMSG to track the optimal speed. To evaluate the performance and effectiveness of the proposed controller, a comparative study between the IBC control and the vector control based on PI controller was carried out through computer simulation. This analysis consists of two case studies including stochastic variation in wind speed and step change in wind speed.
Stability Analysis of DC-link Voltage Control on Autonomous Micro Hydro Power...IAES-IJPEDS
Micro Hydro Power Plant has become one of the interesting topics to be researched nowadays. This paper deals with the stability analysis on control system of excitation voltage in Micro Hydro Power Plant. The control of this voltage can be achieved by controlling the Permanent Magnet Synchronous Machine (PMSM) with particular algorithm so the voltage on the DC-link part of the system can be controlled. Without knowing the exact specification of system parameters, the system will be most likely unstable. The DC-link control system is modeled, simulated, and mathematically analyzed so the parameter specification for the stable system can be obtained.
Self-Tuning Fuzzy Based PI Controller for DFIM Powered by Two Matrix ConvertersIJPEDS-IAES
This paper presents a study of the Doubly Fed Induction Machine (DFIM) powered by two matrix converters; one connected to the stator windings and the other connected to the rotor windings. First, the mathematical model of DFIM and those of the matrix converters are developed. Then, the vector control technique is applied to the DFIM. Fuzzy logic is used in order to automatically adjust the parameters of the PI controller. The performance of this structure under different operating conditions is studied. Particular interest is given to the robustness of the fuzzy logic based control. The operation of the DFIM under overload conditions is also examined. Simulation results obtained in MATLAB/Simulink environment are presented and discussed.
Fuzzy Adaptive Control for Direct Torque in Electric VehicleIAES-IJPEDS
This paper presents a technique to control the electric vehicle (EV) speed and torque at any curve. Our propulsion model consists of two permanent magnet synchronous (PMSM) motors. The fuzzy adaptive PI controller is used to adjust the different static error constants, as per the speed error. The suggested based on the direct torque fuzzy control (DTFC). A Mamdani type fuzzy direct torque controller is first developed and then rules are modified using stator current membership functions. The computations are ensured by the electronic differential, this driving process permit to steer each driving wheels at any curve separately.Modeling and simulation are carried out using the Matlab/Simulink tool to investigate the performance of the proposed system.
ENERGY EFFICIENT VARIABLE SPEED HIGH POWER FACTOR THREE PHASE INDUCTION MOTOR...Journal For Research
Paper presents a new energy efficient technique of three phase AC to AC voltage control using medium frequency pulse width modulation and extinction angle control. This technique is deployed to obtain independent control on speed and power factor of the three phase induction motor, using four semiconductor controllable switches. The technique has been realized using AC freewheeling switch. Power factor (PF) of induction motor reduces as it depends on the load parameters, thus induction motor draws more current, increase stator copper losses. Increased stator copper losses of induction motor causes depreciation of power factor and efficiency. Proposed drive maintains power factor of induction motor at unity for controllable speed of the motor. Thus reduces current consumption of the motor at low speeds. Stator copper losses also reduce and efficiency of the motor is improved. Advantage of proposed drive is its higher efficiency and unity power factor with simplicity of control. .If number of motors are driven using the proposed drive, plenty of power conservation is possible.
Speed control of three phase im by vf open and close loop methodeSAT Journals
Abstract This paper presents the simulation method to control the speed of three phase induction motor by v/f method. Simulation model for speed control in both open loop and close loop is shown here because these motors are the most widely used electrical motor due to the reliability, cheaper cost and thew. Out of the several methods of speed control of an induction such as change of number of poles, variation in frequency, variable stator voltage, constant V/f control, variable rotor resistance, slip recovery method etc., the closed loop constant V/f speed control method is most widely used. Pulse width modulated inverter is the basic requirement of the scheme. Here first a PWM Inverter is modeled and its outputs is fed to the Induction Motor drivesA MATLAB SIMULINK MODEL was designed to successfully implement Open Loop V/f Control on a PWM-Inverter fed three-phase Induction Motor, and the torque is observed to be constant for various rotor speeds. Then a MATLAB model for Closed-Loop V/f Control on a PWM-Inverter fed 3-phase Induction Motor. It was noticed that using a Closed-Loop scheme with a Proportional Integral gave a superior way of controlling the speed of an Induction motor. Keywords: Close loop control, Modelling, Matlab, Open loop control, PWM inverter, Simulink
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
QUICK DYNAMIC TORQUE CONTROL IN DTC-HYSTERESIS-BASED INDUCTION MOTOR BY USING...ijiert bestjournal
Induction machines are widely employed in industries due to their r ugged structure,high maintainability and economy than DC motors. There has been constant development in the i nduction motor drive system and their implementation in industrial applications. The improvement of switching speed of power electronic devices has enabled control techniques which possess high switching f requency and feasibility of high efficiency drive systems. In this pretext,Direct Torque Contr ol (DTC) was introduced to obtain quick and better dynamic torque response. The DTC scheme in its basic c onfiguration comprises torque and flux estimator DTC controller,stator voltage vector selector and voltage source inverter. Direct Torque Control of induction motor has increasingly become the best alternative to Field- Oriented Control methods. The performance of an induction motor under the classical Direct Torque Control method and improved scheme have been studied and confirmed by simulation using MATLAB.
The efficiency of analyzing the rotor currents of asynchronous electric drives with frequency control is substantiated in the article. To assess the quality of torque generation in the engine it is suggested to use the spectral analysis of these currents and the fundamental harmonic, as the most accurate "conformity" of slip in an asynchronous motor. The proposed method showed that "sensorless vector" control leads to the appearance of high-frequency harmonics with significant amplitude. Because of these harmonics, a non-sinusoidal electromagnetic moment is created and the performance of the drive is decreased. The most effective method of torque generation is the frequency control with positive stator current feedback. This control is dominated by pronounced harmonic components, which indicates the proximity of this structure to linear and significantly better controllability of the drives, which makes promising their use in high-tech mechanisms, in particular, in industrial robots. Simulation and experiments confirm the proposed theoretical propositions.
In this article, we are interested in the improvement of the performances of Doubly Fed Induction Machine (DFIM) operating in motor mode by the use of the direct torque control (DTC). Firstly, we focused on the modeling of the DFIM and the study of the principle of functioning of the DTC control. Then, we implement this control on the Matlab/Simulink environment. Secondly, we present the simulation results of the proposed control. The analysis of these results shows clearly that the system based on the DFIM studied follows perfectly the set points, what allowed us to justify the efficiency of the elaborate control.
Numerous studies had been made to improve the switched reluctance motor operation depend on the modification of the machine design, proposing the converter designs and/or applying a suitable control method. This paper introduces the field orientation control method for that motor using a simple and very efficient DC-DC converter topology. This control method is presented by two techniques; first technique is the advance of the turn-on switching angle and the other technique is the retard/delay of the turn-off switching angle. Instantaneous and average motor characteristics are obtained using Matlab/Simulink software package. Comparison between the simulation results presented using two converter types. A precise speed and torque control are obtained. The average total torque per current is maximized.
A comparative study of performance of AC and DC electric drive control system...journalBEEI
In electric drive control systems, the main goal is to maintain the driving motor speed to meet the mechanism’s requirements. In some practical industrial applications the mechanically-coupled load to the motor shaft has a varying mass during the system operation. Therefore, the change of mass changes the value of the moment of inertia of the system. The moment of inertia impacts the system operation, particularly the transient performance. Therefore, the variation of moment of inertia on the motor shaft during its operation creates additional challenges to accomplish a high-quality speed control. The main purpose of the current work is to study the impact of the variation of moment of inertia on the performance of both AC and DC electric drive control systems and to make a comparison between them. A mathematical analysis and simulations of the control system models had been presented; one time with three-phase induction motor and another time with DC motor, both with variable moment of inertia. A simulation of both systems had been accomplished using the Simulink software in MATLAB. The simulation results of operation of these systems have been analysed in order to get useful conclusions and recommendations for the electric drive control system designer.
Vector Control of Three-Phase Induction Motor with Two Stator Phases Open-Cir...IJPEDS-IAES
Variable frequency drives are used to provide reliable dynamic systems and
significant reduction in usage of energy and costs of the induction motors.
Modeling and control of faulty or an unbalanced three-phase induction motor
is obviously different from healthy three-phase induction motor. Using
conventional vector control techniques such as Field-Oriented Control (FOC)
for faulty three-phase induction motor, results in a significant torque and
speed oscillation. This research presented a novel method for vector control
of three-phase induction motor under fault condition (two-phase open circuit
fault). The proposed method for vector control of faulty machine is based on
rotor FOC method. A comparison between conventional and modified
controller shows that the modified controller has been significantly reduced
the torque and speed oscillations.
Speed Control of The Three Phase Induction Motor via changing the line voltageYazan Yousef
This report introduces a method of speed control of the three-phase induction motor driving a fan using the MATLAB. A MATLAB code and Simulink are used to propose the system and to study the speed control method. The method is to control the speed by changing the line voltage. Moreover, the motor performance especially the torque and power are studied during varying the voltage.
BLDC motor driven electric skateboard using SVPWM IJECEIAES
Several problems are faced by today’s generation. One of them is the increase in pollution in our everyday life. Each of us can play a part in reducing this by using some environmentally friendly method such as cycles which requires mechanical force. Another way to accomplish this is by using electricity to produce this mechanical force i.e. electric motor. In this paper BLDC motor driven electric skateboard is designed with mathematical calculation, verified with simulation and developed as a experimental setup.
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology
Optimal turn on and turn-off angles for torque ripple minimization of switche...eSAT Journals
Abstract Due to double saliency nature and non-linear magnetic characteristics the torque ripple is high in Switched Reluctance Motor. The torque ripple depends on the operating speed, current and turn off and turn-on angles of the converter. The performance of the motor is analyzed for Hysteresis Current Control with Fan type load with respect to torque ripple. The SRM with Hysteresis Current Control is analyzed for different combinations of turn-off and turn-on at a fixed reference speed to find out a pair of turn-on and turn-off angles at which torque ripple is minimum. Key Words: Switched Reluctance Motor, Torque Ripple, Hysteresis Current Control
Fault Analysis of DFIG under Grid DisturbancesIJERA Editor
Doubly-fed induction generators (DFIG) are widely used in variable-speed variable-pitch wind energy
generation systems. These machines are controlled with the power converters connected to the rotor, where the
controlled power is only a fraction, approximately equal to the slip of the stator power. This characteristics of the
DFIG has increased the wind energy penetration, but it is more prone to the electrical grid disturbances. These
disturbances are classified as the voltage dips and the line faults. In the first section of this paper, PWM control
of the DFIG for maximum power extraction is presented. In the second section, the behaviour of the DFIG under
the various grid disturbances are modelled. In this paper, the behaviour of the wind turbines are studied through
various simulations done in the LABview environment.
Experimental Study of the Boost Converter under Current Mode ControlIAES-IJPEDS
This paper presents the practical analysis of Boost converter operating in
continuous conduction mode under current control. We start by theconverter
modeling, then experimental results will be exposed where we propose an
experimental circuit, to study the influence of the variation of different
circuit parameters such as reference current, input voltage and load. We also
analyze the control technique performances. The experimental results are
given and interpreted in each case.
This paper focuses on the modeling and control of a wind energy conversion chain using a permanent magnet synchronous machine. This system behaves a turbine, a generator, DC/DC and DC/AC power converters. These are connected on both sides to the DC bus, where the inverter is followed by a filter which is connected to the grid. In this paper, we have been used two types of controllers. For the stator side converter, we consider the Takagi-Sugeno approach where the parameters of controller have been computed by the theory of linear matrix inequalities. The stability synthesis has been checked using the Lyapunov theory. According to the grid side converter, the proportional integral controller is exploited to keep a constant voltage on the DC bus and control both types of powers. The simulation results demonstrate the robustness of the approach used.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Stability Analysis of DC-link Voltage Control on Autonomous Micro Hydro Power...IAES-IJPEDS
Micro Hydro Power Plant has become one of the interesting topics to be researched nowadays. This paper deals with the stability analysis on control system of excitation voltage in Micro Hydro Power Plant. The control of this voltage can be achieved by controlling the Permanent Magnet Synchronous Machine (PMSM) with particular algorithm so the voltage on the DC-link part of the system can be controlled. Without knowing the exact specification of system parameters, the system will be most likely unstable. The DC-link control system is modeled, simulated, and mathematically analyzed so the parameter specification for the stable system can be obtained.
Self-Tuning Fuzzy Based PI Controller for DFIM Powered by Two Matrix ConvertersIJPEDS-IAES
This paper presents a study of the Doubly Fed Induction Machine (DFIM) powered by two matrix converters; one connected to the stator windings and the other connected to the rotor windings. First, the mathematical model of DFIM and those of the matrix converters are developed. Then, the vector control technique is applied to the DFIM. Fuzzy logic is used in order to automatically adjust the parameters of the PI controller. The performance of this structure under different operating conditions is studied. Particular interest is given to the robustness of the fuzzy logic based control. The operation of the DFIM under overload conditions is also examined. Simulation results obtained in MATLAB/Simulink environment are presented and discussed.
Fuzzy Adaptive Control for Direct Torque in Electric VehicleIAES-IJPEDS
This paper presents a technique to control the electric vehicle (EV) speed and torque at any curve. Our propulsion model consists of two permanent magnet synchronous (PMSM) motors. The fuzzy adaptive PI controller is used to adjust the different static error constants, as per the speed error. The suggested based on the direct torque fuzzy control (DTFC). A Mamdani type fuzzy direct torque controller is first developed and then rules are modified using stator current membership functions. The computations are ensured by the electronic differential, this driving process permit to steer each driving wheels at any curve separately.Modeling and simulation are carried out using the Matlab/Simulink tool to investigate the performance of the proposed system.
ENERGY EFFICIENT VARIABLE SPEED HIGH POWER FACTOR THREE PHASE INDUCTION MOTOR...Journal For Research
Paper presents a new energy efficient technique of three phase AC to AC voltage control using medium frequency pulse width modulation and extinction angle control. This technique is deployed to obtain independent control on speed and power factor of the three phase induction motor, using four semiconductor controllable switches. The technique has been realized using AC freewheeling switch. Power factor (PF) of induction motor reduces as it depends on the load parameters, thus induction motor draws more current, increase stator copper losses. Increased stator copper losses of induction motor causes depreciation of power factor and efficiency. Proposed drive maintains power factor of induction motor at unity for controllable speed of the motor. Thus reduces current consumption of the motor at low speeds. Stator copper losses also reduce and efficiency of the motor is improved. Advantage of proposed drive is its higher efficiency and unity power factor with simplicity of control. .If number of motors are driven using the proposed drive, plenty of power conservation is possible.
Speed control of three phase im by vf open and close loop methodeSAT Journals
Abstract This paper presents the simulation method to control the speed of three phase induction motor by v/f method. Simulation model for speed control in both open loop and close loop is shown here because these motors are the most widely used electrical motor due to the reliability, cheaper cost and thew. Out of the several methods of speed control of an induction such as change of number of poles, variation in frequency, variable stator voltage, constant V/f control, variable rotor resistance, slip recovery method etc., the closed loop constant V/f speed control method is most widely used. Pulse width modulated inverter is the basic requirement of the scheme. Here first a PWM Inverter is modeled and its outputs is fed to the Induction Motor drivesA MATLAB SIMULINK MODEL was designed to successfully implement Open Loop V/f Control on a PWM-Inverter fed three-phase Induction Motor, and the torque is observed to be constant for various rotor speeds. Then a MATLAB model for Closed-Loop V/f Control on a PWM-Inverter fed 3-phase Induction Motor. It was noticed that using a Closed-Loop scheme with a Proportional Integral gave a superior way of controlling the speed of an Induction motor. Keywords: Close loop control, Modelling, Matlab, Open loop control, PWM inverter, Simulink
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
QUICK DYNAMIC TORQUE CONTROL IN DTC-HYSTERESIS-BASED INDUCTION MOTOR BY USING...ijiert bestjournal
Induction machines are widely employed in industries due to their r ugged structure,high maintainability and economy than DC motors. There has been constant development in the i nduction motor drive system and their implementation in industrial applications. The improvement of switching speed of power electronic devices has enabled control techniques which possess high switching f requency and feasibility of high efficiency drive systems. In this pretext,Direct Torque Contr ol (DTC) was introduced to obtain quick and better dynamic torque response. The DTC scheme in its basic c onfiguration comprises torque and flux estimator DTC controller,stator voltage vector selector and voltage source inverter. Direct Torque Control of induction motor has increasingly become the best alternative to Field- Oriented Control methods. The performance of an induction motor under the classical Direct Torque Control method and improved scheme have been studied and confirmed by simulation using MATLAB.
The efficiency of analyzing the rotor currents of asynchronous electric drives with frequency control is substantiated in the article. To assess the quality of torque generation in the engine it is suggested to use the spectral analysis of these currents and the fundamental harmonic, as the most accurate "conformity" of slip in an asynchronous motor. The proposed method showed that "sensorless vector" control leads to the appearance of high-frequency harmonics with significant amplitude. Because of these harmonics, a non-sinusoidal electromagnetic moment is created and the performance of the drive is decreased. The most effective method of torque generation is the frequency control with positive stator current feedback. This control is dominated by pronounced harmonic components, which indicates the proximity of this structure to linear and significantly better controllability of the drives, which makes promising their use in high-tech mechanisms, in particular, in industrial robots. Simulation and experiments confirm the proposed theoretical propositions.
In this article, we are interested in the improvement of the performances of Doubly Fed Induction Machine (DFIM) operating in motor mode by the use of the direct torque control (DTC). Firstly, we focused on the modeling of the DFIM and the study of the principle of functioning of the DTC control. Then, we implement this control on the Matlab/Simulink environment. Secondly, we present the simulation results of the proposed control. The analysis of these results shows clearly that the system based on the DFIM studied follows perfectly the set points, what allowed us to justify the efficiency of the elaborate control.
Numerous studies had been made to improve the switched reluctance motor operation depend on the modification of the machine design, proposing the converter designs and/or applying a suitable control method. This paper introduces the field orientation control method for that motor using a simple and very efficient DC-DC converter topology. This control method is presented by two techniques; first technique is the advance of the turn-on switching angle and the other technique is the retard/delay of the turn-off switching angle. Instantaneous and average motor characteristics are obtained using Matlab/Simulink software package. Comparison between the simulation results presented using two converter types. A precise speed and torque control are obtained. The average total torque per current is maximized.
A comparative study of performance of AC and DC electric drive control system...journalBEEI
In electric drive control systems, the main goal is to maintain the driving motor speed to meet the mechanism’s requirements. In some practical industrial applications the mechanically-coupled load to the motor shaft has a varying mass during the system operation. Therefore, the change of mass changes the value of the moment of inertia of the system. The moment of inertia impacts the system operation, particularly the transient performance. Therefore, the variation of moment of inertia on the motor shaft during its operation creates additional challenges to accomplish a high-quality speed control. The main purpose of the current work is to study the impact of the variation of moment of inertia on the performance of both AC and DC electric drive control systems and to make a comparison between them. A mathematical analysis and simulations of the control system models had been presented; one time with three-phase induction motor and another time with DC motor, both with variable moment of inertia. A simulation of both systems had been accomplished using the Simulink software in MATLAB. The simulation results of operation of these systems have been analysed in order to get useful conclusions and recommendations for the electric drive control system designer.
Vector Control of Three-Phase Induction Motor with Two Stator Phases Open-Cir...IJPEDS-IAES
Variable frequency drives are used to provide reliable dynamic systems and
significant reduction in usage of energy and costs of the induction motors.
Modeling and control of faulty or an unbalanced three-phase induction motor
is obviously different from healthy three-phase induction motor. Using
conventional vector control techniques such as Field-Oriented Control (FOC)
for faulty three-phase induction motor, results in a significant torque and
speed oscillation. This research presented a novel method for vector control
of three-phase induction motor under fault condition (two-phase open circuit
fault). The proposed method for vector control of faulty machine is based on
rotor FOC method. A comparison between conventional and modified
controller shows that the modified controller has been significantly reduced
the torque and speed oscillations.
Speed Control of The Three Phase Induction Motor via changing the line voltageYazan Yousef
This report introduces a method of speed control of the three-phase induction motor driving a fan using the MATLAB. A MATLAB code and Simulink are used to propose the system and to study the speed control method. The method is to control the speed by changing the line voltage. Moreover, the motor performance especially the torque and power are studied during varying the voltage.
BLDC motor driven electric skateboard using SVPWM IJECEIAES
Several problems are faced by today’s generation. One of them is the increase in pollution in our everyday life. Each of us can play a part in reducing this by using some environmentally friendly method such as cycles which requires mechanical force. Another way to accomplish this is by using electricity to produce this mechanical force i.e. electric motor. In this paper BLDC motor driven electric skateboard is designed with mathematical calculation, verified with simulation and developed as a experimental setup.
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology
Optimal turn on and turn-off angles for torque ripple minimization of switche...eSAT Journals
Abstract Due to double saliency nature and non-linear magnetic characteristics the torque ripple is high in Switched Reluctance Motor. The torque ripple depends on the operating speed, current and turn off and turn-on angles of the converter. The performance of the motor is analyzed for Hysteresis Current Control with Fan type load with respect to torque ripple. The SRM with Hysteresis Current Control is analyzed for different combinations of turn-off and turn-on at a fixed reference speed to find out a pair of turn-on and turn-off angles at which torque ripple is minimum. Key Words: Switched Reluctance Motor, Torque Ripple, Hysteresis Current Control
Fault Analysis of DFIG under Grid DisturbancesIJERA Editor
Doubly-fed induction generators (DFIG) are widely used in variable-speed variable-pitch wind energy
generation systems. These machines are controlled with the power converters connected to the rotor, where the
controlled power is only a fraction, approximately equal to the slip of the stator power. This characteristics of the
DFIG has increased the wind energy penetration, but it is more prone to the electrical grid disturbances. These
disturbances are classified as the voltage dips and the line faults. In the first section of this paper, PWM control
of the DFIG for maximum power extraction is presented. In the second section, the behaviour of the DFIG under
the various grid disturbances are modelled. In this paper, the behaviour of the wind turbines are studied through
various simulations done in the LABview environment.
Experimental Study of the Boost Converter under Current Mode ControlIAES-IJPEDS
This paper presents the practical analysis of Boost converter operating in
continuous conduction mode under current control. We start by theconverter
modeling, then experimental results will be exposed where we propose an
experimental circuit, to study the influence of the variation of different
circuit parameters such as reference current, input voltage and load. We also
analyze the control technique performances. The experimental results are
given and interpreted in each case.
This paper focuses on the modeling and control of a wind energy conversion chain using a permanent magnet synchronous machine. This system behaves a turbine, a generator, DC/DC and DC/AC power converters. These are connected on both sides to the DC bus, where the inverter is followed by a filter which is connected to the grid. In this paper, we have been used two types of controllers. For the stator side converter, we consider the Takagi-Sugeno approach where the parameters of controller have been computed by the theory of linear matrix inequalities. The stability synthesis has been checked using the Lyapunov theory. According to the grid side converter, the proportional integral controller is exploited to keep a constant voltage on the DC bus and control both types of powers. The simulation results demonstrate the robustness of the approach used.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Double flux orientation control for a doubly fed induction generator based wi...eSAT Journals
Abstract
Abstract In this paper we present a new strategy of vector control for variable speed wind turbines (WT) based on Doubly-Fed
Induction Generator (DFIG). It is based on the principle of a double flux orientation (DFOC) of stator and rotor at the same time.
This one creates the orthogonally between the two oriented fluxes, which must be strictly observed, and therefore leads to generate a
linear and decoupled control of the active and reactive powers. The simulation was performed using Simulink of Matlab to show the
effectiveness of the proposed control strategy.
Index Terms: Doubly fed induction generator (DFIG), wind turbine (WT), double flux Orientation control, vector control.
Wind energy has many advantages, it does not pollute and it is an inexhaustible source. However, the cost of this energy is still too high to compete with traditional fossil sources. The yield of a wind turbine depends on three parameters: the power of the wind, the turbine power curve and the ability of the generator to respond to fluctuations in the wind. This article presented the MPPT of a wind turbine system equipped with an asynchronous generator has dual power under MatlabSimulink program, in the first time we simulated all the conversion chain with complete model of DFIG and vector control in second stepthen applied the extracted maximum power MPPT strategists, this command is effective and has several advantages it offered to kept the maximum power delivered to network despite all the parameter is change.
The Nine-Switch Inverter(NSI) is a recently developed dual output converter. It can be used to drive two three-phase loads independently. As a substitute to two separate conventional voltage source inverters, the NSI has been, already, proposed in various industrial applications to reduce the numberof semiconductor switches and its associated energy losses and drive circuitry. On the other hand, the Direct Torque Control(DTC) is a robust control scheme of AC motors, which consist of selecting proper state vectors of a conventional voltage source inverter. The NSI, having a different working principle from the conventional voltage source inverter and taking into account the varying influence of active space vectors on motor’s torque and stator flux, a Direct Torque Control is suggested in this paper to, efficiently, drive two induction motors independently, while minimizing the torque and stator flux ripples of both motors. Simulations results confirm the effectiveness of the proposed algorithm. In addition, application of this newly proposed control scheme in operation of an Electric Vehicule (EV) is demonstrated.
Power Control of Wind Turbine Based on Fuzzy Sliding-Mode ControlIJPEDS-IAES
This paper presents the study of a variable speed wind energy conversion system (WECS) using a Wound Field Synchronous Generator (WFSG) based on a Fuzzy sliding mode control (FSMC) applied to achieve control of active and reactive powers exchanged between the stator of the WFSG and the grid to ensure a Maximum Power Point Tracking (MPPT) of a wind energy conversion system. However the principal drawback of the sliding mode, is the chattering effect which characterized by torque ripple, this phenomena is undesirable and harmful for the machines, it generates noises and additional forces of torsion on the machine shaft. A direct fuzzy logic controller is designed and the sliding mode controller is added to compensate the fuzzy approximation errors. The simulation results clearly indicate the effectiveness and validity of the proposed method, in terms of convergence, time and precision.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Adaptive Fuzzy Logic Control of Wind Turbine EmulatorIJPEDS-IAES
In this paper, a Wind Turbine Emulator (WTE) based on a separately excited direct current (DC) motor is studied. The wind turbine was emulated by controlling the torque of the DC motor. The WTE is used as a prime mover for Permanent Magnet Synchronous Machine (PMSM). In order to extract maximum power from the wind, PI and Fuzzy controllers were tested. Simulation results are given to show performance of proposed fuzzy control system in maximum power points tracking in a wind energy conversion system under various wind conditions. The strategy control was implemented in simulation using MATLAB/Simulink.
Analytical Description of Dc Motor with Determination of Rotor Damping Consta...theijes
DC motor as an electric machine have been applied in numerous control systems. However, a critical parameter of interest that must be evaluated in designing a DC motor based system is the damping constant of the rotor. This paper analytically examines how to determine the damping constant of the rotor of a 12V DC motor, with the determination based on the following parameters: Armature resistance (Ra), inductance (La), Capacitance, the Stall current and the Angular rate of excitation of the motor with varying armature excitation of the current. These parameters help to ascertain the maximum and the minimum operating limit of the motor so as not to exceed the boundary-operating limits of the 12V motor. Experiments were performed in the laboratory and at the end of the analysis, the result shows that the value of damping constant of a 12V DC motor was -3.317 10-4 N-m-sec 2 . This parameter can be factored in future control system designs.
Study and comparison results of the field oriented control for photovoltaic w...journalBEEI
In this papier, a low-cost solar photovoltaic water pumping system based on an induction motor without the use of chemical energy storage is presented. In literature, we can find several Maximum Power Point Tracking Algorithms, the choice of the algorithm is according to the nature of application. In this article, Variable Step Size Incremental Conductance MPPT method has been developed since it is fast and has less oscillations. The studied photovoltaic pumping system contains a centrifugal pump which is driven by a three-phase asynchronous motor. To control the water flow, the field-oriented control has been implemented. The control system is applied on two cities with different climatic conditions to evaluate their performance. The photovoltaic pumping system is developed using the MATLAB/Simulink software to discuss the results obtained. Consequently, the proposed MPPT based on the incremental conductance variable step shows good performances in terms of efficiency and tracking speed.
Experiment based comparative analysis of stator current controllers using pre...journalBEEI
The stator current control loop plays an important role in ensuring the quality of electric drives interm of producing fast and adequate required torque. When the current controller provides ideal responses, speed control design subsequently is in charge of improving the system performances. Classical PID control is commonly used in current loop design, this paper presents the comparative analysis of current stator controller using proportional integral control and predictive current control (PCC) in field-oriented control-based induction motor drives, with rigidly coupled loads. The experimental results show system responses with PID and PCC. Informative experiment-based analysis provides primary guidance in selection between the two controls.
Comparison of Estimated Torques Using Low Pass Filter and Extended Kalman Fil...IAES-IJPEDS
Torque calculation process is one of the major concerns for controlling induction motors in industry, which requires very accurate state estimation of unmeasurable variables of nonlinear models. This can be solved if the variables used for torque calculation is accurately estimated. This paper presents a torque calculation based on a voltage model represented with a low-pass filter (LPF), and an extended Kalman filter (EKF). The experimental results showed that the estimated torque at low speed based on EKF is more accurate in the expense of more complicated and larger computational time.
Advanced Control of Wind Electric Pumping System for Isolated Areas ApplicationIAES-IJPEDS
The supply water in remote areas of windy region is one of most attractive application of wind energy conversion. This paper proposes an advanced controller suitable for wind-electric pump in isolated applications in order to have a desired debit from variation of reference speed of the pump also the control scheme of DC voltage of SIEG for feed the pump are presented under step change in wind speed. The simulation results showed a good performance of the global proposed control system.
This paper presents simulation and experimental results of anti-windup PI controller to improve induction machine speed control based on direct torque control (DTC) strategy. Problems like rollover can arise in conventional PI controller due to saturation effect. In order to avoid such problems anti-windup PI controller is presented. This controller is simple for implementation in practice. The proposed anti-windup PI controller demonstrates better dynamic step changes response in speed in terms of overshoots. All simulation work was done using Simulink in the MATLAB software. The experimental results were obtained by practical implementation on a dSPACE 1104 board for a 1.5 KW induction machine. Simulation and experimental results have proven a good performance and verified the validity of the presented control strategy.
This research presents a very important industrial issue of controlling the production target, despite changing loads. Engines of various types, whether synchronous or synchronous, operate on single and three phase AC, DC motors or special motors such as stepper and servo. In all these motors, the speed control of the torque and speed of the above motors has gained considerable importance. There are three main ways reviewed in the current search, the second that completes the previous research referred to in the references. The three methods are PID method, LQR method and feeding –forward control methods. A real DC motor was used in electrical engineering machine laboratory at University of Diyala, Iraq. Where the actual parameters of the DC motor were actually calculated. The practical parameters were then integrated into the three control method Matlab codes for the purpose of comparing the results and representing the motor performance in the indicated control methods.
Mechanical properties of hybrid fiber reinforced concrete for pavementseSAT Journals
Abstract
The effect of addition of mono fibers and hybrid fibers on the mechanical properties of concrete mixture is studied in the present
investigation. Steel fibers of 1% and polypropylene fibers 0.036% were added individually to the concrete mixture as mono fibers and
then they were added together to form a hybrid fiber reinforced concrete. Mechanical properties such as compressive, split tensile and
flexural strength were determined. The results show that hybrid fibers improve the compressive strength marginally as compared to
mono fibers. Whereas, hybridization improves split tensile strength and flexural strength noticeably.
Keywords:-Hybridization, mono fibers, steel fiber, polypropylene fiber, Improvement in mechanical properties.
Material management in construction – a case studyeSAT Journals
Abstract
The objective of the present study is to understand about all the problems occurring in the company because of improper application
of material management. In construction project operation, often there is a project cost variance in terms of the material, equipments,
manpower, subcontractor, overhead cost, and general condition. Material is the main component in construction projects. Therefore,
if the material management is not properly managed it will create a project cost variance. Project cost can be controlled by taking
corrective actions towards the cost variance. Therefore a methodology is used to diagnose and evaluate the procurement process
involved in material management and launch a continuous improvement was developed and applied. A thorough study was carried
out along with study of cases, surveys and interviews to professionals involved in this area. As a result, a methodology for diagnosis
and improvement was proposed and tested in selected projects. The results obtained show that the main problem of procurement is
related to schedule delays and lack of specified quality for the project. To prevent this situation it is often necessary to dedicate
important resources like money, personnel, time, etc. To monitor and control the process. A great potential for improvement was
detected if state of the art technologies such as, electronic mail, electronic data interchange (EDI), and analysis were applied to the
procurement process. These helped to eliminate the root causes for many types of problems that were detected.
Managing drought short term strategies in semi arid regions a case studyeSAT Journals
Abstract
Drought management needs multidisciplinary action. Interdisciplinary efforts among the experts in various fields of the droughts
prone areas are helpful to achieve tangible and permanent solution for this recurring problem. The Gulbarga district having the total
area around 16, 240 sq.km, and accounts 8.45 per cent of the Karnataka state area. The district has been situated with latitude 17º 19'
60" North and longitude of 76 º 49' 60" east. The district is situated entirely on the Deccan plateau positioned at a height of 300 to
750 m above MSL. Sub-tropical, semi-arid type is one among the drought prone districts of Karnataka State. The drought
management is very important for a district like Gulbarga. In this paper various short term strategies are discussed to mitigate the
drought condition in the district.
Keywords: Drought, South-West monsoon, Semi-Arid, Rainfall, Strategies etc.
Life cycle cost analysis of overlay for an urban road in bangaloreeSAT Journals
Abstract
Pavements are subjected to severe condition of stresses and weathering effects from the day they are constructed and opened to traffic
mainly due to its fatigue behavior and environmental effects. Therefore, pavement rehabilitation is one of the most important
components of entire road systems. This paper highlights the design of concrete pavement with added mono fibers like polypropylene,
steel and hybrid fibres for a widened portion of existing concrete pavement and various overlay alternatives for an existing
bituminous pavement in an urban road in Bangalore. Along with this, Life cycle cost analyses at these sections are done by Net
Present Value (NPV) method to identify the most feasible option. The results show that though the initial cost of construction of
concrete overlay is high, over a period of time it prove to be better than the bituminous overlay considering the whole life cycle cost.
The economic analysis also indicates that, out of the three fibre options, hybrid reinforced concrete would be economical without
compromising the performance of the pavement.
Keywords: - Fatigue, Life cycle cost analysis, Net Present Value method, Overlay, Rehabilitation
Laboratory studies of dense bituminous mixes ii with reclaimed asphalt materialseSAT Journals
Abstract
The issue of growing demand on our nation’s roadways over that past couple of decades, decreasing budgetary funds, and the need to
provide a safe, efficient, and cost effective roadway system has led to a dramatic increase in the need to rehabilitate our existing
pavements and the issue of building sustainable road infrastructure in India. With these emergency of the mentioned needs and this
are today’s burning issue and has become the purpose of the study.
In the present study, the samples of existing bituminous layer materials were collected from NH-48(Devahalli to Hassan) site.The
mixtures were designed by Marshall Method as per Asphalt institute (MS-II) at 20% and 30% Reclaimed Asphalt Pavement (RAP).
RAP material was blended with virgin aggregate such that all specimens tested for the, Dense Bituminous Macadam-II (DBM-II)
gradation as per Ministry of Roads, Transport, and Highways (MoRT&H) and cost analysis were carried out to know the economics.
Laboratory results and analysis showed the use of recycled materials showed significant variability in Marshall Stability, and the
variability increased with the increase in RAP content. The saving can be realized from utilization of recycled materials as per the
methodology, the reduction in the total cost is 19%, 30%, comparing with the virgin mixes.
Keywords: Reclaimed Asphalt Pavement, Marshall Stability, MS-II, Dense Bituminous Macadam-II
Laboratory investigation of expansive soil stabilized with natural inorganic ...eSAT Journals
Abstract
Soil stabilization has proven to be one of the oldest techniques to improve the soil properties. Literature review conducted revealed
that uses of natural inorganic stabilizers are found to be one of the best options for soil stabilization. In this regard an attempt has
been made to evaluate the influence of RBI-81 stabilizer on properties of black cotton soil through laboratory investigations. Black
cotton soil with varying percentages of RBI-81 viz., 0, 0.5, 1, 1.5, 2, and 2.5 percent were studied for moisture density relationships
and strength behaviour of soils. Also the effect of curing period was evaluated as literature review clearly emphasized the strength
gain of soils stabilized with RBI-81 over a period of time. The results obtained shows that the unconfined compressive strength of
specimens treated with RBI-81 increased approximately by 250% for a curing period of 28 days as compared to virgin soil. Further
the CBR value improved approximately by 400%. The studies indicated an increasing trend for soil strength behaviour with
increasing percentage of RBI-81 suggesting its potential applications in soil stabilization.
Influence of reinforcement on the behavior of hollow concrete block masonry p...eSAT Journals
Abstract
Reinforced masonry was developed to exploit the strength potential of masonry and to solve its lack of tensile strength. Experimental
and analytical studies have been carried out to investigate the effect of reinforcement on the behavior of hollow concrete block
masonry prisms under compression and to predict ultimate failure compressive strength. In the numerical program, three dimensional
non-linear finite elements (FE) model based on the micro-modeling approach is developed for both unreinforced and reinforced
masonry prisms using ANSYS (14.5). The proposed FE model uses multi-linear stress-strain relationships to model the non-linear
behavior of hollow concrete block, mortar, and grout. Willam-Warnke’s five parameter failure theory has been adopted to model the
failure of masonry materials. The comparison of the numerical and experimental results indicates that the FE models can successfully
capture the highly nonlinear behavior of the physical specimens and accurately predict their strength and failure mechanisms.
Keywords: Structural masonry, Hollow concrete block prism, grout, Compression failure, Finite element method,
Numerical modeling.
Influence of compaction energy on soil stabilized with chemical stabilizereSAT Journals
Abstract
Increase in traffic along with heavier magnitude of wheel loads cause rapid deterioration in pavements. There is a need to improve
density, strength of soil subgrade and other pavement layers. In this study an attempt is made to improve the properties of locally
available loamy soil using twin approaches viz., i) increasing the compaction of soil and ii) treating the soil with chemical stabilizer.
Laboratory studies are carried out on both untreated and treated soil samples compacted by different compaction efforts. Studies
show that increase in compaction effort results in increase in density of soil. However in soil treated with chemical stabilizer, rate of
increase in density is not significant. The soil treated with chemical stabilizer exhibits improvement in both strength and performance
properties.
Keywords: compaction, density, subgradestabilization, resilient modulus
Geographical information system (gis) for water resources managementeSAT Journals
Abstract
Water resources projects are inherited with overlapping and at times conflicting objectives. These projects are often of varied sizes
ranging from major projects with command areas of millions of hectares to very small projects implemented at the local level. Thus,
in all these projects there is seldom proper coordination which is essential for ensuring collective sustainability.
Integrated watershed development and management is the accepted answer but in turn requires a comprehensive framework that can
enable planning process involving all the stakeholders at different levels and scales is compulsory. Such a unified hydrological
framework is essential to evaluate the cause and effect of all the proposed actions within the drainage basins.
The present paper describes a hydrological framework developed in the form of a Hydrologic Information System (HIS) which is
intended to meet the specific information needs of the various line departments of a typical State connected with water related aspects.
The HIS consist of a hydrologic information database coupled with tools for collating primary and secondary data and tools for
analyzing and visualizing the data and information. The HIS also incorporates hydrological model base for indirect assessment of
various entities of water balance in space and time. The framework would be maintained and updated to reflect fully the most
accurate ground truth data and the infrastructure requirements for planning and management.
Keywords: Hydrological Information System (HIS); WebGIS; Data Model; Web Mapping Services
Forest type mapping of bidar forest division, karnataka using geoinformatics ...eSAT Journals
Abstract
The study demonstrate the potentiality of satellite remote sensing technique for the generation of baseline information on forest types
including tree plantation details in Bidar forest division, Karnataka covering an area of 5814.60Sq.Kms. The Total Area of Bidar
forest division is 5814Sq.Kms analysis of the satellite data in the study area reveals that about 84% of the total area is Covered by
crop land, 1.778% of the area is covered by dry deciduous forest, 1.38 % of mixed plantation, which is very threatening to the
environmental stability of the forest, future plantation site has been mapped. With the use of latest Geo-informatics technology proper
and exact condition of the trees can be observed and necessary precautions can be taken for future plantation works in an appropriate
manner
Keywords:-RS, GIS, GPS, Forest Type, Tree Plantation
Factors influencing compressive strength of geopolymer concreteeSAT Journals
Abstract
To study effects of several factors on the properties of fly ash based geopolymer concrete on the compressive strength and also the
cost comparison with the normal concrete. The test variables were molarities of sodium hydroxide(NaOH) 8M,14M and 16M, ratio of
NaOH to sodium silicate (Na2SiO3) 1, 1.5, 2 and 2.5, alkaline liquid to fly ash ratio 0.35 and 0.40 and replacement of water in
Na2SiO3 solution by 10%, 20% and 30% were used in the present study. The test results indicated that the highest compressive
strength 54 MPa was observed for 16M of NaOH, ratio of NaOH to Na2SiO3 2.5 and alkaline liquid to fly ash ratio of 0.35. Lowest
compressive strength of 27 MPa was observed for 8M of NaOH, ratio of NaOH to Na2SiO3 is 1 and alkaline liquid to fly ash ratio of
0.40. Alkaline liquid to fly ash ratio of 0.35, water replacement of 10% and 30% for 8 and 16 molarity of NaOH and has resulted in
compressive strength of 36 MPa and 20 MPa respectively. Superplasticiser dosage of 2 % by weight of fly ash has given higher
strength in all cases.
Keywords: compressive strength, alkaline liquid, fly ash
Experimental investigation on circular hollow steel columns in filled with li...eSAT Journals
Abstract
Composite Circular hollow Steel tubes with and without GFRP infill for three different grades of Light weight concrete are tested for
ultimate load capacity and axial shortening , under Cyclic loading. Steel tubes are compared for different lengths, cross sections and
thickness. Specimens were tested separately after adopting Taguchi’s L9 (Latin Squares) Orthogonal array in order to save the initial
experimental cost on number of specimens and experimental duration. Analysis was carried out using ANN (Artificial Neural
Network) technique with the assistance of Mini Tab- a statistical soft tool. Comparison for predicted, experimental & ANN output is
obtained from linear regression plots. From this research study, it can be concluded that *Cross sectional area of steel tube has most
significant effect on ultimate load carrying capacity, *as length of steel tube increased- load carrying capacity decreased & *ANN
modeling predicted acceptable results. Thus ANN tool can be utilized for predicting ultimate load carrying capacity for composite
columns.
Keywords: Light weight concrete, GFRP, Artificial Neural Network, Linear Regression, Back propagation, orthogonal
Array, Latin Squares
Experimental behavior of circular hsscfrc filled steel tubular columns under ...eSAT Journals
Abstract
This paper presents an outlook on experimental behavior and a comparison with predicted formula on the behaviour of circular
concentrically loaded self-consolidating fibre reinforced concrete filled steel tube columns (HSSCFRC). Forty-five specimens were
tested. The main parameters varied in the tests are: (1) percentage of fiber (2) tube diameter or width to wall thickness ratio (D/t
from 15 to 25) (3) L/d ratio from 2.97 to 7.04 the results from these predictions were compared with the experimental data. The
experimental results) were also validated in this study.
Keywords: Self-compacting concrete; Concrete-filled steel tube; axial load behavior; Ultimate capacity.
Evaluation of punching shear in flat slabseSAT Journals
Abstract
Flat-slab construction has been widely used in construction today because of many advantages that it offers. The basic philosophy in
the design of flat slab is to consider only gravity forces; this method ignores the effect of punching shear due to unbalanced moments
at the slab column junction which is critical. An attempt has been made to generate generalized design sheets which accounts both
punching shear due to gravity loads and unbalanced moments for cases (a) interior column; (b) edge column (bending perpendicular
to shorter edge); (c) edge column (bending parallel to shorter edge); (d) corner column. These design sheets are prepared as per
codal provisions of IS 456-2000. These design sheets will be helpful in calculating the shear reinforcement to be provided at the
critical section which is ignored in many design offices. Apart from its usefulness in evaluating punching shear and the necessary
shear reinforcement, the design sheets developed will enable the designer to fix the depth of flat slab during the initial phase of the
design.
Keywords: Flat slabs, punching shear, unbalanced moment.
Evaluation of performance of intake tower dam for recent earthquake in indiaeSAT Journals
Abstract
Intake towers are typically tall, hollow, reinforced concrete structures and form entrance to reservoir outlet works. A parametric
study on dynamic behavior of circular cylindrical towers can be carried out to study the effect of depth of submergence, wall thickness
and slenderness ratio, and also effect on tower considering dynamic analysis for time history function of different soil condition and
by Goyal and Chopra accounting interaction effects of added hydrodynamic mass of surrounding and inside water in intake tower of
dam
Key words: Hydrodynamic mass, Depth of submergence, Reservoir, Time history analysis,
Evaluation of operational efficiency of urban road network using travel time ...eSAT Journals
Abstract
Efficiency of the road network system is analyzed by travel time reliability measures. The study overlooks on an important measure of
travel time reliability and prioritizing Tiruchirappalli road network. Traffic volume and travel time were collected using license plate
matching method. Travel time measures were estimated from average travel time and 95th travel time. Effect of non-motorized vehicle
on efficiency of road system was evaluated. Relation between buffer time index and traffic volume was created. Travel time model has
been developed and travel time measure was validated. Then service quality of road sections in network were graded based on
travel time reliability measures.
Keywords: Buffer Time Index (BTI); Average Travel Time (ATT); Travel Time Reliability (TTR); Buffer Time (BT).
Estimation of surface runoff in nallur amanikere watershed using scs cn methodeSAT Journals
Abstract
The development of watershed aims at productive utilization of all the available natural resources in the entire area extending from
ridge line to stream outlet. The per capita availability of land for cultivation has been decreasing over the years. Therefore, water and
the related land resources must be developed, utilized and managed in an integrated and comprehensive manner. Remote sensing and
GIS techniques are being increasingly used for planning, management and development of natural resources. The study area, Nallur
Amanikere watershed geographically lies between 110 38’ and 110 52’ N latitude and 760 30’ and 760 50’ E longitude with an area of
415.68 Sq. km. The thematic layers such as land use/land cover and soil maps were derived from remotely sensed data and overlayed
through ArcGIS software to assign the curve number on polygon wise. The daily rainfall data of six rain gauge stations in and around
the watershed (2001-2011) was used to estimate the daily runoff from the watershed using Soil Conservation Service - Curve Number
(SCS-CN) method. The runoff estimated from the SCS-CN model was then used to know the variation of runoff potential with different
land use/land cover and with different soil conditions.
Keywords: Watershed, Nallur watershed, Surface runoff, Rainfall-Runoff, SCS-CN, Remote Sensing, GIS.
Estimation of morphometric parameters and runoff using rs & gis techniqueseSAT Journals
Abstract
Land and water are the two vital natural resources, the optimal management of these resources with minimum adverse environmental
impact are essential not only for sustainable development but also for human survival. Satellite remote sensing with geographic
information system has a pragmatic approach to map and generate spatial input layers of predicting response behavior and yield of
watershed. Hence, in the present study an attempt has been made to understand the hydrological process of the catchment at the
watershed level by drawing the inferences from moprhometric analysis and runoff. The study area chosen for the present study is
Yagachi catchment situated in Chickamaglur and Hassan district lies geographically at a longitude 75⁰52’08.77”E and
13⁰10’50.77”N latitude. It covers an area of 559.493 Sq.km. Morphometric analysis is carried out to estimate morphometric
parameters at Micro-watershed to understand the hydrological response of the catchment at the Micro-watershed level. Daily runoff
is estimated using USDA SCS curve number model for a period of 10 years from 2001 to 2010. The rainfall runoff relationship of the
study shows there is a positive correlation.
Keywords: morphometric analysis, runoff, remote sensing and GIS, SCS - method
-
Effect of variation of plastic hinge length on the results of non linear anal...eSAT Journals
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The velocity control of the electro hydraulic servo system
1. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
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Volume: 03 Issue: 11 | Nov-2014, Available @ http://www.ijret.org 73
THE VELOCITY CONTROL OF THE ELECTRO-HYDRAULIC SERVO
SYSTEM
Magdy M. Abdelhameed1
, M. A. Abdelaziz2
, A. Bakarman3
1
Head of department, Professor, Mechatronics Engineering Department, Ain Shams University, Cairo
2
Assistant Professor, Mechatronics Engineering Department, Ain Shams University, Cairo
3
Engineering, Mechatronics Engineering Department, Ain Shams University, Cairo
Abstract
In general two basic methods are used for controlling the velocity of a hydraulic cylinder. First by an axial variable-displacement
pump for controls flow to the cylinder. This configuration is commonly known as a hydrostatic transmission. Second by
proportional valve powered by a constant-pressure source, such as a pressure compensated pump, drives the hydraulic cylinder.
In this study, the electro-hydraulic servo system (EHSS) for velocity control of hydraulic cylinder is investigated experimentally
and its analysis theoretically. Where the controlled hydraulic cylinder is altered by a swashplate axial piston pump or by
proportional valve to achieve velocity control. The theoretical part includes the derivation of the mathematical model equations
of combination system. Velocity control system for hydraulic cylinder using simple (PID) controller to get constant velocity
range of hydraulic cylinder under applied external variable loads . An experimental set-up is constructed, which consists of the
hydraulic test pump unit, the electro-hydraulic proportional valve unit, the hydraulic actuator unit , the external load control unit
and interfacing electronic unit. The experimental results show that PID controller can be achieve good velocity control by
variable displacement axial piston pump and also by proportional valve under external loads variations.
Keywords: Velocity control, Swashplate, Proportional valve, Hydraulic cylinder, PID controller, Axial piston pump
--------------------------------------------------------------------***----------------------------------------------------------------------
1. INTRODUCTION
EHSS is widely used in many industrial applications and
mobile systems because of their high power to weight ratio,
high stiffness, fast response, self cooling, good positioning
capabilities, etc. EHSS systems can be classified into two
different systems, hydraulic valve-controlled systems and
hydraulic displacement-controlled systems. The hydraulic
valve-controlled systems that have been applied widely in
industrial servo control have higher response but lower
energy efficiency. In contrast, hydraulic displacement-
controlled systems, where displacement is adjusted by a
variable displacement pump, have higher energy efficiency
but lower control response owing to their complexity.
Velocity control of EHSS problems are treated by
(Anderson, 1988; Bake, 1992; Jen and Lee,1992; Chern and
Wu, 1992; Lierschaft, 1993; Boes, 1995; Huang and Wang,
1995; Bernzen, 1999 )[9]. This study will focus on the
velocity control of hydraulic cylinder by two methods. First
method by swashplate axial piston pump where swashplat
controlled by stepper motor to change flowrate of pump and
then control velocity of hydraulic cylinder. Second method
by Proportional valve to control flow from pump to cylinder
and hence control velocity of hydraulic cylinder.
The rest of the paper is organized as follows. In Section 2, a
short description of the experimental set-up. Then, in
Section 3 mathematical model for the system is presented.
In section 4, the implementation of PID controller is
presented. Experimental results are presented in Section 5
and finally the paper is concluded.
2. EXPERIMENTAL SETUP DESCRIPTION
Figure 1 illustrates schematically the proposed system, it
consists of five main units; the hydraulic test pump unit, the
electro-hydraulic proportional valve unit, the hydraulic
actuator unit, the load disturbance unit and interfacing unit.
As shown in Figure 1, the unit of the hydraulic pump
consists mainly of the test pump (1), which is a piston pump
type (Model PVQ 06L ASY, OilGear) that has flowrate
about 6 L/min at 1000 rpm. The test pump is coupled with
an electric motor (2) that has 1.5 kW of output power and
uses a flexible coupling to absorb any axial and/or lateral
vibration between the connected shafts. The swashplate is
rigidly connected to a stepper motor (3), which drives the
swashplate to change its inclination angle.
As shown in Figure 1, the main part of electro-hydraulic
proportional valve unit is directional control valve (5),which
is 4/3 proportional control valve (Model TGL 55074,
ORSTA hydraulic). Two solenoids (6) actuate the spool of
valve in two sides using a coil. When the coil is energized,
the spool is moved to the desired position.
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Fig-1: Schematic diagram of the proposed system setup.
The actuator used is double acting hydraulic cylinder (8) as
shown in figure 1 . Hydraulic cylinder is equipped with
potentiometer transducer (12) (Gefran type) which has a
useful stroke of 250 mm. The velocity of hydraulic cylinder
detected with potentiometer, when potentiometer measured
physical position and convert it to analog signals. The
analog signals are sent to acquisition system and with
derivative function can be estimated the velocity of
hydraulic cylinder.
The load disturbance unit is built to simulate different
modes of change in external load. When return to figure 1
,seen that mechanical spring (9) represents to virtual
different load patterns. Mechanical spring connected to
hydraulic cylinder (8) in one side, while in other side
connected to ball screw lead (11) and dc motor (10).
Through properties of mechanical spring, find that the
changes force of spring proportional to its compression
distance. So that, the motor with ball screw lead can control
the changes force of spring based on other acting side force
through hydraulic cylinder. Light distance transducer (13)
used to estimated external different loads patterns by
knowing variable length of spring and fed back into
electronic control and data acquisition.
In interfacing and electronic unit, the PC sends an input
voltage signal through an analog and digital output ports on
the data acquisition card (DAQ) board (NI USB-6009) to the
drivers and amplifiers (such as swashplate stepper motor
driver and solenoid valve amplifier). The output voltage
from each sensor (potentiometer and light distance sensor)
is sent to the PC through analog input ports on the DAQ.
Simulink and Matlab are used as the user interface to
generate and analyze all data to and from the PC. A
photograph of the constructed experimental test set-up is
shown in Figure 2.
Fig-2: Photograph of the experimental setup.
3. MATHEMATICAL ANALYSIS AND
MODELING OF EHSS
3.1 Pump Unit Modeling
3.1.1 Mathematical Model of the Stepper Motor of
Swashplate
If a sinusoidal characteristic of the magnetic field in the air
gap is assumed, the contribution of each phase j on the
motor torque TMj can be written as, [1][2][3]
TMj = km sin Φj + Nθp t Ij(t) (1)
Where, km is the motor constant , θp is the actual rotor
position, Ij is the current in the coil as function of time, Φj is
the location of coil j in the stator, N is the number of rotor
pole and P is the number of stator phases.
However the current Ij(t) in the coil is a function of the
supplied voltage Vj (t) and the coil properties. A general
equation between Ij(t)and Vj (t) is given by,
Vj t = emfj + RIj t + L
dIj t
dt
(2)
Where emfj is the electromotive force induced in the phase
j, R is the resistance of the coils and L is the inductance of
the coils However, the emf in each coil can be expressed as
emfj = km sin Φj + Nθp t ωd (3)
Where ωd is the rotational velocity of the rotor.
The total torque produced by the stepper is given as
TM = TMj
P
j=1 (4)
3. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
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Using Equation (4), and considering the equation of motion
of a stepper motor,
TM = Jd
dωd
dt
+ Bdωd + Td (5)
Where, Jd is the inertia of the rotor, Bd is the viscous
damping constant and Td is the Load torque acting on the
stepper motor shaft.
The angular velocity is given by
ωd =
dθp
dt
(6)
Hence for a 2 phase PM motor with Nr rotor teeth and the
two phases Φj at 0 and (π/2) the following state space
equations can be derived.
dωd
dt
=
−km sin Nθp Ia +km cos Nθp Ib −Bd ωd −Tl
Jd
(7)
dIa
dt
=
Va −RIa +km ωd sin Nθp
L
(8)
dIb
dt
=
Vb −RIb +km ωd sin Nθp
L
(9)
3.1.2 Mathematical Model of the Pump
3.1.2.1 Torque Model
Figure 3 illustrates the components and forces that have an
effect on the total torque.
Fig-3: Forces that give rise to torques acting on the
swashplate and yoke assembly
The load exerted by the swashplate can be divided into the
following torques: [4][5-7]
Torque produced by friction forces, Tf,
Torque relating to the pressure effect, Tp,
Torque relating to the rotation of the barrel, Tr and
Torque required to overcome the swash plate inertia,
Jp θp
Td = Jp θp + Tf - Tp - Tr ( 10)
where Jp is the average moment of inertia of swashplate
yoke assembly and Td is the torque applied to the yoke by
the stepper motor.
The frictional torque includes coulomb friction, viscous
damping friction and stiction. As mentioned, the stiction
friction is assumed to be negligible. Hence the frictional
torque can be represented by
Tf = sign θp Tfc + Bpθp (11)
where Tfc is the torque produced by the coulomb friction
force, Bp is the damping coefficient of the swashplate yoke
assembly.
However, the torque applied to the swashplate due to the
pressure effect is significant. This torque is a function of
both the pump pressure and swashplate angle and can be
written as
Tp = Kp1Pp − Kp2Pp θp (12)
where Kp1 is the pressure torque constant, Kp2 is the pressure
torque constant and Pp is the pump pressure.
When the pump is in operation, there is a torque applied to
the swashplate by the piston slippers. This force is a result
of the inertia of pistons and the shoe plate and is known to
be a function of the swashplate angle. Therefore, this torque
is related to the rotation of the barrel and can be represented
as
Tr = −S1 − S2θp (13)
where S1 is the simplified pump model constant and S2 is the
simplified pump model constant.
Substituting Eqs. (11)-(13) into Eq.(10),
Td = Jp θp + S1 + S2θp + sgn θp Tfc + Bpθp + Kp2ppθp −
Kp1PP (14)
3.1.2.2 Flow Model of the Pump
The displacement of the pump is defined as follows:
[4][8][5-7]
Dp = NApRptanθp/π (15)
where Dp is the displacement of the pump, Rp is the radius
of the piston pitch, N is the Number of pistons and Ap is the
Area of the piston.
Assuming that the rotational speed of the prime mover is ωp,
the ideal flow rate of the pump is as follows
Qpidea = ωpDp = ωpNApRptanθp/π (16)
From the continuity equation, the flow equation for the
pump can be written as:
Qpidea − Qip − Qep − Qp =
Vp
B
dpp
dt
(17)
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where Qp is the output flow of the pump, Qip is the internal
leakage flow of the pump, Qep is the external leakage flow
of the pump, Vp is the volume of the pump forward chamber
and B is the bulk modulus of the fluid.
Since the suction pressure is assumed to be zero, the leakage
flow of the pump (including the internal leakage and the
external leakage flow) can be approximated by:
Qlp = Qip + Qep = Ctp pp (18)
where Ctp is the Total leakage flow coefficient.
Substituting Equations (16) and (18) into Equation (17),
yields
ωpNApRptanθp/π − Ctp pp − Qp =
Vp
B
dPp
dt
(19)
Equation (19) is thus the flow model of the pump.
3.2 Proportional Valve Model
3.2.1 Dynamics of the Spool Valve
The dynamic of a spool valve follows approximately a linear
differential equation of second order described in
equation,[1][35]
mvxv + cxv + kxv = F (20)
where mv is the mass of the spool, c the damping factor ,k is
the spring stiffness and xv is the spool valve position. The
force F can be seen as an input to the system, e.g. the input
voltage to the valves.
By substituting k = mv ωn
2
and c = 2𝛇 𝐤𝐦 𝐯, equation (20)
becomes
xv + 2ωn 𝛇xv + ωn
2
xv = ωn
2
kvu (21)
where u is the voltage control input, kv is the proportional
valve gain, ωn is the natural frequency and ζ is the damping
ratio.
Written equation (21)as a relation between input and output
finally yields in the transfer function of the form,
xv(s)
u(s)
=
ωn
2 kv
s2+2ωn 𝛇𝐬+ωn
2 (22)
3.2.2 Flowrate Through the Proportional Valve
Restriction Areas
The proportional valve spool displacement throttles oil flow
through the four control gaps of the valve since the valve
open center type as in figure 4., [11]
Qa = Cdw(xvmax − xv)
2(pA −pt )
ρ
(23)
Qb = Cdwxv
2(pp −pA )
ρ
(24)
Qc = Cdw(xvmax − xv)
2(pp −pB )
ρ
(25)
Qd = Cdwxv
2(pB −pt)
ρ
(26)
Where pp is the Supply pressure, pt is the Return pressure,
pA and pB are the pressure acting on the two sides of the
piston of the cylinder, ρ is the Oil density, Cd Discharge
coefficient and w is the width of the valve port.
QA = Qb−Qa (27)
QB = Qc−Qd (28)
Fig-4: Hydraulic actuator with four-way valve configuration
3.3 Hydraulic Cylinder Modeling
As in figure 4 the application of the continuity equation to
the cylinder chambers yields the following equations,[9][11]
pA =
B
Vo +Ap xp
(QA − Apxp) dt (29)
pB =
B
Vo −Ap xp
(QB − Apxp) dt (30)
where Ap is the Piston area, Vo is the half of volume of oil
filling the cylinder, B is the fluid bulk modulus and xp is the
piston position.
The piston is driven by the pressure difference in the
hydraulic cylinder chambers. The equation of motion of the
piston becomes as follows,[9][2]
pA − pB Ap = mxp + fv xp + FL (31)
Where m is the total mass of the piston and fv is the viscous
friction cofficient and FL is the external load variables.
3.4 Modeling of External loads Unit
Such as in Figure 1, the external load can be represented by
mechanical spring which attached by ball screw to control
the force. Th equation of external force formulated as
follows,
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FL = kmech (xp + x screw ) (32)
Where kmech is the stiffness of spring and xscrew is the
displacement of spring due to ball screw motion.
4. PROPORTION INTGRAL DERIVATIVE (PID)
CONTROLLER
Classical PID controllers are very popular in industries
because they can improve both the transient response and
steady state error of the system at the same time. The
performance specifications of the systems such as rise time,
overshoot, settling time and error steady state can be
improved by tuning value of parameters KP, KI and KD of
the PID controller, because each component has its own
special purposes. KP or proportional controller is used to
assure the output reach the reference input. However, the
output of the system with this controller will never reach
zero steady state error. In order to obtain zero or very small
steady state error, KI or integral controller is given to the
system. Derivative controller or KD will improve the speed
performance of the system. Mathematically it is represented
as
Fig-5: Block diagram of a PID controller.
u k = KP e k + KI e ik
i=0 + KD[e k − e(k − 1)] (33)
where e(k) is the error signal.
The PID control method has been widely used in industry
during last several decades because of its simplicity. To tune
these parameters, the model is linearized around different
equilibrium points. PID controller could be determined by
many methods which lead to regulate the (PID) controller
for example trial and error method or Ziegler and Nichols
method.
5. THE EXPERIMENTAL RESULTS
The aim of this section is to test the velocity control
strategy on the experimental set-up that shown in Figure 2.
PID controller applied to the variable pump controlled and
valve controlled by simulink and DAQ as the development
platform and shown in figure 6 and 7. A testing of response
of the system was performed using a step input to ensure
constant velocity of hydraulic cylinder .
Fig-6: The control velocities by variable pump and developed by simulink
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Fig-7: The control velocity by proportional valve and developed by simulink
5.1. Velocity Control of Hydraulic Cylinder by
Proportional Valve
Figure 8 shows the velocity form controlled under variable
linear external load. The parameter values tuned of the PID
controller are P=1.7, I=0.9, and D=0.1. Where external load
form changed, velocity response can be presented in figure 9
by same PID parameters. In figure 10 shows the tested
velocity response without any external load by PID
parameters as P= 1.2, I= 0.8 and D = 0.1.
(a)
(b)
Fig-8: Experimental results of constant velocity by
controlled valve under form of external loads.
(a)
(b)
Fig-9: Experimental results of constant velocity by
controlled valve under form of external loads
Fig-10: Experimental results of constant velocity by
controlled valve without any external loads
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5.2 Velocity Control of Hydraulic Cylinder by
Swashplate Axial Piston Pump
Fig. 11 shows the velocity form controlled under variable
external loads. The parameters values tuned of the PID
controller are P=70, I=70 and D=5.
Fig-11: Experimental results of constant velocity by
variable pump under external loads
6. CONCLUSION
A model equations for EHSS has been derived. PID
controller theory is introduced as the control technique to
accomplish this goal in this study, and the controllers
designed using this method are validated using experimental
tests. The comparison of the results between test responses
indicates the rising time of the various velocity valve
controlled responses are at 5 sec., while the rising time of
the velocity variable pump controlled response is at 6 sec.
Thus, the control velocity by controlled valve has higher
responses than variable pump controlled.
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the Arm Movements of a Stepper Motor
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[2] A. B. Kabde and A. Dominic Savio, “Position
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[3] Robert H. Bishop, „The Mechatronic Handbook‟,
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BIOGRAPHIES
Magdy Abdelhameed: received his
B.S.c., M.S.c. and PhD degrees from
AinShams University, faculty of
Engineering, Mechanical Engineering
Department in 1983, 1989 and 1994
respectively. Currently he is enrolled as a
head of the mechatronics Department at AinShams
University, faculty of Engineering. His research interests
lie in the field of electro-hydraulic system.
Mohamed A. Abdelaziz: received his
B.S.c., degrees from Ain Shams
University, faculty of Engineering,
Mechanical Engineering department in
2001. He then received his M.S.c and
PhD. degrees from University of Illinois,
Chicago, USA, faculty of Engineering, Mechanical
Engineering Department in 2007. Currently He is enrolled
as an associate professor in the Automotive Engineering
Department at Ain Shams University, faculty of Engineering
.His research interests lie in the field of automotive systems.
Amgad A. Bakarman : received his
B.Sc. degree in Mechanical engineering
department from Aden Univerity, Aden,
Yemen, in 2008 and the M.Sc. student in
Mechatronics at Ain Shams University,
Cairo, Egypt, Currently.