This document summarizes research on controlling an electromechanical actuator for camless engines. It describes identifying physical parameters of the actuator based on frequency response data. A feedforward and feedback controller was developed to control the actuator for soft valve seating, achieving a seating speed of 0.61 m/s with low variability. A repetitive learning controller was also designed and testing, leading to further reduced seating speeds of 0.061 m/s.
Simulation, bifurcation, and stability analysis of a SEPIC converter control...IJECEIAES
This article presents some results of SEPIC converter dynamics when controlled by a center pulse width modulator controller (CPWM). The duty cycle is calculated using the ZAD (Zero Average Dynamics) technique. Results obtained using this technique show a great variety of non-linear phenomena such as bifurcations and chaos, as parameters associated with the switching surface. These phenomena have been studied in the present paper in numerical form. Simulations were done in MATLAB.
Design of an adaptive state feedback controller for a magnetic levitation sy...IJECEIAES
This paper presents designing an adaptive state feedback controller (ASFC) for a magnetic levitation system (MLS), which is an unstable system and has high nonlinearity and represents a challenging control problem. First, a nonadaptive state feedback controller (SFC) is designed by linearization about a selected equilibrium point and designing a SFC by pole-placement method to achieve maximum overshoot of 1.5% and settling time of 1s (5% criterion). When the operating point changes, the designed controller can no longer achieve the design specifications, since it is designed based on a linearization about a different operating point. This gives rise to utilizing the adaptive control scheme to parameterize the state feedback controller in terms of the operating point. The results of the simulation show that the operating point has significant effect on the performance of nonadaptive SFC, and this performance may degrade as the operating point deviates from the equilibrium point, while the ASFC achieves the required design specification for any operating point and outperforms the state feedback controller from this point of view.
Analysis of Simple Maglev System using SimulinkArslan Guzel
The document is a PowerPoint presentation analyzing a simple maglev system using Simulink. It includes:
- An introduction to maglev systems and their applications.
- Circuit diagrams and explanations of the position sensor, electromagnet actuator, and other system components.
- Derivations of the system's mathematical model and equations in state space form for both nonlinear and linear controller approaches.
- Descriptions of the Simulink models created to simulate the system, including blocks for the generalized system, nonlinear controller, and determining voltage and current.
- Analysis of simulation results for two air gap scenarios, comparing graphs of position, velocity, acceleration, and other signals between the scenarios.
DC Motor Modelling & Design Fullstate Feedback Controller Idabagus Mahartana
This document describes the design of a full-state feedback controller with an integral controller for a DC motor system to control angular position. It first presents the mathematical model and parameters of the DC motor. It then shows the open-loop response has infinite rise time. A full-state feedback controller is designed to meet criteria of settling time < 2s, overshoot < 5%, and steady-state error < 1%. Pole locations are varied to analyze responses. Finally, the model is modified to simulate a disturbance response by adding a load torque term.
DESIGN ,ANALYSIS &COMPARISON OF VARIOUS CONTROLLERS FOR DC MOTOR SPEED CON...Varun Kambrath
This document discusses the design, analysis, and comparison of various controllers for DC motor speed control. It first introduces DC motors and their applications. It then presents the modelling and characteristics of a sample DC motor. The document analyzes and compares the performance of open loop, closed loop, proportional, integral, proportional-integral, proportional-derivative, and proportional-integral-derivative controllers for the motor. It evaluates the controllers based on rise time, settling time, overshoot, and steady state error. Finally, it examines the gain and phase margins of the controlled motor system.
The control of motor rotation speed by the change of resistor resistance value in armature circuit is called ‘resistor control”. For the regulation of resistance value R0, included in armature winding circuit, we can use various technical solutions. The most used solution is the discrete variation of armature added resistance value by shunting its parts with contactors contacts. Nowadays, the change of resistor resistance in armature circuit can be realized by shunting with a given porosity γ of resistor R0 trough electronic keys. In this paper, we study the design of control system represented on figure 1.
This paper presents a nonlinear Integral backstepping control approach based on field oriented control technique, applied to a Double Star Induction Machine ‘DSIM’ feed by two power voltage sources. We present this technique of integral backstepping by using reduced and complete Model of DSIM. The objective is to improve the robustness of machine under internal parameter variation with nonlinear Integral backstepping control. The robustness test results obtained by simulation prove the effectiveness of control with using complete model of DSIM.
Simulation, bifurcation, and stability analysis of a SEPIC converter control...IJECEIAES
This article presents some results of SEPIC converter dynamics when controlled by a center pulse width modulator controller (CPWM). The duty cycle is calculated using the ZAD (Zero Average Dynamics) technique. Results obtained using this technique show a great variety of non-linear phenomena such as bifurcations and chaos, as parameters associated with the switching surface. These phenomena have been studied in the present paper in numerical form. Simulations were done in MATLAB.
Design of an adaptive state feedback controller for a magnetic levitation sy...IJECEIAES
This paper presents designing an adaptive state feedback controller (ASFC) for a magnetic levitation system (MLS), which is an unstable system and has high nonlinearity and represents a challenging control problem. First, a nonadaptive state feedback controller (SFC) is designed by linearization about a selected equilibrium point and designing a SFC by pole-placement method to achieve maximum overshoot of 1.5% and settling time of 1s (5% criterion). When the operating point changes, the designed controller can no longer achieve the design specifications, since it is designed based on a linearization about a different operating point. This gives rise to utilizing the adaptive control scheme to parameterize the state feedback controller in terms of the operating point. The results of the simulation show that the operating point has significant effect on the performance of nonadaptive SFC, and this performance may degrade as the operating point deviates from the equilibrium point, while the ASFC achieves the required design specification for any operating point and outperforms the state feedback controller from this point of view.
Analysis of Simple Maglev System using SimulinkArslan Guzel
The document is a PowerPoint presentation analyzing a simple maglev system using Simulink. It includes:
- An introduction to maglev systems and their applications.
- Circuit diagrams and explanations of the position sensor, electromagnet actuator, and other system components.
- Derivations of the system's mathematical model and equations in state space form for both nonlinear and linear controller approaches.
- Descriptions of the Simulink models created to simulate the system, including blocks for the generalized system, nonlinear controller, and determining voltage and current.
- Analysis of simulation results for two air gap scenarios, comparing graphs of position, velocity, acceleration, and other signals between the scenarios.
DC Motor Modelling & Design Fullstate Feedback Controller Idabagus Mahartana
This document describes the design of a full-state feedback controller with an integral controller for a DC motor system to control angular position. It first presents the mathematical model and parameters of the DC motor. It then shows the open-loop response has infinite rise time. A full-state feedback controller is designed to meet criteria of settling time < 2s, overshoot < 5%, and steady-state error < 1%. Pole locations are varied to analyze responses. Finally, the model is modified to simulate a disturbance response by adding a load torque term.
DESIGN ,ANALYSIS &COMPARISON OF VARIOUS CONTROLLERS FOR DC MOTOR SPEED CON...Varun Kambrath
This document discusses the design, analysis, and comparison of various controllers for DC motor speed control. It first introduces DC motors and their applications. It then presents the modelling and characteristics of a sample DC motor. The document analyzes and compares the performance of open loop, closed loop, proportional, integral, proportional-integral, proportional-derivative, and proportional-integral-derivative controllers for the motor. It evaluates the controllers based on rise time, settling time, overshoot, and steady state error. Finally, it examines the gain and phase margins of the controlled motor system.
The control of motor rotation speed by the change of resistor resistance value in armature circuit is called ‘resistor control”. For the regulation of resistance value R0, included in armature winding circuit, we can use various technical solutions. The most used solution is the discrete variation of armature added resistance value by shunting its parts with contactors contacts. Nowadays, the change of resistor resistance in armature circuit can be realized by shunting with a given porosity γ of resistor R0 trough electronic keys. In this paper, we study the design of control system represented on figure 1.
This paper presents a nonlinear Integral backstepping control approach based on field oriented control technique, applied to a Double Star Induction Machine ‘DSIM’ feed by two power voltage sources. We present this technique of integral backstepping by using reduced and complete Model of DSIM. The objective is to improve the robustness of machine under internal parameter variation with nonlinear Integral backstepping control. The robustness test results obtained by simulation prove the effectiveness of control with using complete model of DSIM.
This document presents a design of power system stabilizer (PSS) and static var compensator (SVC) controllers using particle swarm optimization (PSO) algorithm to improve power system stability. The controllers are tested on a single machine infinite bus system model in MATLAB/Simulink. Simulation results show that the proposed PSS and SVC controller designed using PSO effectively damps out oscillations under different disturbances like balanced/unbalanced faults and small disturbances, improving stability performance compared to conventional PSS alone. The parameters of the controllers are optimized using PSO to maximize efficiency. Nonlinear time-domain simulations demonstrate the effectiveness and robustness of the proposed control scheme in enhancing power system stability over a wide range of operating conditions.
Applying Parametric Functional Approximations for Teaching Electromechanical ...IOSRJEEE
In this paper functional approximations for the parameters of a DC machine are proposed. These nonlinear algebraic approximations are based on the experimental data that are obtained by carrying out several steady state and transient tests, besides, this method links mathematics and practical analysis of electromechanical systems, allowing students to improve their academic performance and comprehension by comparing estimated values with measured data. An excellent dynamic model results of combining the well known state space description and these parametric functional approximations. This augmented model provides reliable results even during demanding large-excursion transient conditions
Electromagnetic Levitation (control project)Salim Al Oufi
This project is about controlling the position of a magnetic ball by using PID controller. The ball position controlled by changing the magnetic field from the solenoid. Sensors give a feedback of the position of the magnetic ball. This is the simplest description for this paper.
The document describes a project to create a quasi-equilibrium state pendulum using a DC motor attached to a rod. The motor drives a propeller to allow the rod to swing. Angular position is measured by a potentiometer. The system is modeled and controlled using Scilab/Xcos. Initial PID tuning is done using Ziegler-Nichols method. Future work proposed includes expanding the controllable angle range and implementing advanced controllers like adaptive control to improve response. The appendix lists components used and conclusions reiterate the potential applications and limitations of PID control for this system.
The Polysolenoid Linear Motor (PLM) have been playing a crucial role in many industrial aspects because it provides a straight motion directly without mediate mechanical actuators. Some control methods for PLM based on Rotational Motor are applied to obtain several good performances, but position and velocity constraints which are important in real systems are ignored. In this paper, we analysis control problem of tracking position in PLM under state-independent disturbances via min-max model predictive control. The proposed controller brings tracking position error converge to zero and satisfies state including position and velocity and input constraints. The simulation results validity a good efficiency of the proposed controller.
Controller design of inverted pendulum using pole placement and lqreSAT 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.
This document proposes a sensorless estimator for speed, armature temperature, and resistance in brushed DC machines using a cascade-forward neural network (CFNN) and quasi-Newton BFGS backpropagation. A thermal model is used to estimate temperature without a thermal sensor. Simulation results show the CFNN estimates match the model outputs, estimating speed with less than 2% error. This approach provides sensorless simultaneous estimation of multiple parameters without some limitations of prior methods like the extended Kalman filter.
This document presents an implementation of space vector modulation (SVM) for a two-level three-phase inverter using a dSPACE DS1104 controller. It describes the principles of SVM, including voltage vector modeling, sector detection, and pulse generation. Hardware experiments were conducted to validate a SVM control algorithm developed in Simulink. Results showed line voltages from the real hardware matched simulation. THD comparisons confirmed SVM provides lower distortion and higher fundamental output than sinusoidal PWM. The dSPACE system allows real-time testing of control algorithms on actual hardware.
Stochastic estimation methods for induction motor transient thermal monitorin...Mellah Hacene
The induction machine, because of its robustness and low-cost, is commonly used in the industry. Nevertheless, as every type of electrical machine, this machine suffers of some limitations. The most important one is the working temperature which is the dimensioning parameter for the definition of the nominal working point and the machine lifetime. Due to a strong demand concerning thermal monitoring methods appeared in the industry sector. In this context, the adding of temperature sensors is not acceptable and the studied methods tend to use sensorless approaches such as observators or parameters estimators like the extended Kalman Filter (EKF). Then the important criteria are reliability, computational cost ad real time implementation.
The use of ekf to estimate the transient thermal behaviour of induction motor...Mellah Hacene
This document summarizes a journal article that examines using an Extended Kalman Filter (EKF) to estimate the transient thermal behavior of an induction motor drive without sensors. It first reviews common thermal modeling methods for induction motors, including simple, finite element, and electrical equivalent circuit models. It then presents the authors' thermal model of the induction motor in state-space form, incorporating linear relationships between resistance and temperature, power losses, heat transfer, and temperature rise in the stator and rotor. The resulting state equations can be used by the EKF for sensorless estimation of temperatures and resistances.
Cascade forward neural network based on resilient backpropagation for simulta...Mellah Hacene
Cascade-Forward Neural Network Based on Resilient Backpropagation for Simultaneous Parameters and State Space Estimations of Brushed DC Machines
Advances in Modelling and Analysis B
PID Controller Design for a Real Time Ball and Beam System – A Double Integra...idescitation
In this paper, the authors have discussed and shown
how to tune the PID controller in closed loop with time-delay
for the double integrator systems for a particular stability
margins. In math model it is assumed that time delay (ô) of
the plant is known. As a case study the authors have consid-
ered the mathematical model of the real-time beam and ball
system and analyzed the simulation and real time response.
Pwm Control Strategy for Controlling Of Parallel Rectifiers In Single Phase T...IJERA Editor
This paper explains that how to develop and design, control of single phase to three phase drive system. The
proposed topology of drive system consisting of two parallel connected rectifiers, inverter and induction motor,
connected through inductor and capacitor, where used to produce balanced output to the motor drive. The main
objective of this proposed method is to reduce the circulating currents and harmonic distortions at the converter
input side, here the control strategy of drive system is PWM (pulse width modulations techniques) control
strategy, the proposed topology also provides fault compensation in the case of short circuit faults and failure of
switches for uninterrupted Power supplies. We also develop and simulate the MATLAB models for proposed
drive system, by using MATLAB/ Simulink the output results simulate and observed.
MODELLING AND SIMULATION OF INVERTED PENDULUM USING INTERNAL MODEL CONTROLJournal For Research
The internal model control (IMC) philosophy relies on the internal model principle, which states that control can be achieved only if the control system encapsulates, either implicitly or explicitly, some representation of the process to be controlled. In particular, if the control scheme is developed based on an exact model of the process, then perfect control is theoretically possible. Transfer function of Inverted Pendulum is selected as the base of design, which examines IMC controller. Matlab/simulink is used to simulate the procedures and validate the performance. The results shows robustness of the IMC and got graded responses when compared with PID. Furthermore, a comparison between the PID and IMC was shows that IMC gives better response specifications.
This document summarizes a research paper that proposes a new control technique for a Doubly Fed Induction Generator (DFG) used in variable speed wind turbines. The technique uses a nonlinear sliding mode control approach with an exponential reaching law (ERL) to control the active and reactive powers generated by the wind turbine. Simulation results show that this sliding mode control with ERL is more robust and improves power quality and stability compared to traditional sliding mode control approaches. It reduces chattering phenomenon while also accelerating the system response for better tracking of the desired control objectives.
This document discusses symmetrical components analysis of unbalanced three-phase power systems. It defines symmetrical components as three balanced systems that a unbalanced three-phase system can be resolved into. It describes how to calculate the positive, negative, and zero sequence components of voltages and currents using phasor transformations. Examples are provided to demonstrate how to calculate symmetrical components for given unbalanced voltage and current values. The document also discusses sequence impedances of transformers and how to model zero sequence networks of different transformer configurations.
Power transformer faults diagnosis using undestructive methods and ann for dg...Mellah Hacene
Power transformer faults diagnosis using undestructive methods (Roger and IEC) and artificial neural network for dissolved gas analysis applied on the functional transformer in the Algerian north-eastern: a comparative study
Bouchaoui Lahcene, Kamel Eddine Hemsas, Hacene Mellah, saad eddine benlahneche
Nowadays, power transformer aging and failures are viewed with great attention in power transmission industry. Dissolved gas analysis (DGA) is classified among the biggest widely used methods used within the context of asset management policy to detect the incipient faults in their earlier stage in power transformers. Up to now, several procedures have been employed for the lecture of DGA results. Among these useful means, we find Key Gases, Rogers Ratios, IEC Ratios, the historical technique less used today Doernenburg Ratios, the two types of Duval Pentagons methods, several versions of the Duval Triangles method and Logarithmic Nomograph. Problem. DGA data extracted from different units in service served to verify the ability and reliability of these methods in assessing the state of health of the power transformer. Aim. An improving the quality of diagnostics of electrical power transformer by artificial neural network tools based on two conventional methods in the case of a functional power transformer at Sétif province in East North of Algeria. Methodology. Design an inelegant tool for power transformer diagnosis using neural networks based on traditional methods IEC and Rogers, which allows to early detection faults, to increase the reliability, of the entire electrical energy system from transport to consumers and improve a continuity and quality of service. Results. The solution of the problem was carried out by using feed-forward back-propagation neural networks implemented in MATLAB-Simulink environment. Four real power transformers working under different environment and climate conditions such as: desert, humid, cold were taken into account. The practical results of the diagnosis of these power transformers by the DGA are presented. Practical value.....
This document summarizes a paper presented at the International Conference on Mechatronics in Kumamoto, Japan in May 2007. The paper presents analysis and implementation of exact model knowledge and direct adaptive control schemes for a 4th order ball and beam system. Two controllers are designed - one using the exact model and one using direct adaptive control. Experimental results show that both controllers can track constant and sinusoidal references for the ball position asymptotically on a physical ball and beam system.
Camless engines eliminate mechanical linkages like camshafts that traditionally open and close intake and exhaust valves. Instead, camless engines use electro-hydraulic or electromechanical systems to provide infinite control over valve timing, lift, and duration. This allows for greater engine efficiency and power. Sensors detect operating conditions and an electronic control unit actuates solenoids and hydraulic systems to optimize valve behavior for each situation. While camless engines are more expensive and complex than traditional designs, their performance advantages are expected to lead to their increased adoption over time.
Sturman engines camless digital engines overview articleSteve Wittrig
Benefits of Sturman’s Camless Engine:
Independent valve lift and timing control allows mixed-charge combustion
Low parasitic loss, since most of the conventional valvetrain (including the camshaft) is eliminated
High-speed engine operation (up to 12,000 rpm)
Enables homogeneous charge compression ignition (HCCI) combustion
Enables cylinder de-activation and cylinder balancing
Scalable to any engine size and can be retrofitted to older engines since all the technology is in the head
Compatible with any fuel type
A square lift pattern compared to the lobe profiles a camshaft requires
Can be used to create an internal EGR system
Promises up to 60 percent thermal efficiency
Can be used to help eliminate the need for an exhaust aftertreatment
Only system able to run the Sturman Combustion Cycle
This document presents a design of power system stabilizer (PSS) and static var compensator (SVC) controllers using particle swarm optimization (PSO) algorithm to improve power system stability. The controllers are tested on a single machine infinite bus system model in MATLAB/Simulink. Simulation results show that the proposed PSS and SVC controller designed using PSO effectively damps out oscillations under different disturbances like balanced/unbalanced faults and small disturbances, improving stability performance compared to conventional PSS alone. The parameters of the controllers are optimized using PSO to maximize efficiency. Nonlinear time-domain simulations demonstrate the effectiveness and robustness of the proposed control scheme in enhancing power system stability over a wide range of operating conditions.
Applying Parametric Functional Approximations for Teaching Electromechanical ...IOSRJEEE
In this paper functional approximations for the parameters of a DC machine are proposed. These nonlinear algebraic approximations are based on the experimental data that are obtained by carrying out several steady state and transient tests, besides, this method links mathematics and practical analysis of electromechanical systems, allowing students to improve their academic performance and comprehension by comparing estimated values with measured data. An excellent dynamic model results of combining the well known state space description and these parametric functional approximations. This augmented model provides reliable results even during demanding large-excursion transient conditions
Electromagnetic Levitation (control project)Salim Al Oufi
This project is about controlling the position of a magnetic ball by using PID controller. The ball position controlled by changing the magnetic field from the solenoid. Sensors give a feedback of the position of the magnetic ball. This is the simplest description for this paper.
The document describes a project to create a quasi-equilibrium state pendulum using a DC motor attached to a rod. The motor drives a propeller to allow the rod to swing. Angular position is measured by a potentiometer. The system is modeled and controlled using Scilab/Xcos. Initial PID tuning is done using Ziegler-Nichols method. Future work proposed includes expanding the controllable angle range and implementing advanced controllers like adaptive control to improve response. The appendix lists components used and conclusions reiterate the potential applications and limitations of PID control for this system.
The Polysolenoid Linear Motor (PLM) have been playing a crucial role in many industrial aspects because it provides a straight motion directly without mediate mechanical actuators. Some control methods for PLM based on Rotational Motor are applied to obtain several good performances, but position and velocity constraints which are important in real systems are ignored. In this paper, we analysis control problem of tracking position in PLM under state-independent disturbances via min-max model predictive control. The proposed controller brings tracking position error converge to zero and satisfies state including position and velocity and input constraints. The simulation results validity a good efficiency of the proposed controller.
Controller design of inverted pendulum using pole placement and lqreSAT 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.
This document proposes a sensorless estimator for speed, armature temperature, and resistance in brushed DC machines using a cascade-forward neural network (CFNN) and quasi-Newton BFGS backpropagation. A thermal model is used to estimate temperature without a thermal sensor. Simulation results show the CFNN estimates match the model outputs, estimating speed with less than 2% error. This approach provides sensorless simultaneous estimation of multiple parameters without some limitations of prior methods like the extended Kalman filter.
This document presents an implementation of space vector modulation (SVM) for a two-level three-phase inverter using a dSPACE DS1104 controller. It describes the principles of SVM, including voltage vector modeling, sector detection, and pulse generation. Hardware experiments were conducted to validate a SVM control algorithm developed in Simulink. Results showed line voltages from the real hardware matched simulation. THD comparisons confirmed SVM provides lower distortion and higher fundamental output than sinusoidal PWM. The dSPACE system allows real-time testing of control algorithms on actual hardware.
Stochastic estimation methods for induction motor transient thermal monitorin...Mellah Hacene
The induction machine, because of its robustness and low-cost, is commonly used in the industry. Nevertheless, as every type of electrical machine, this machine suffers of some limitations. The most important one is the working temperature which is the dimensioning parameter for the definition of the nominal working point and the machine lifetime. Due to a strong demand concerning thermal monitoring methods appeared in the industry sector. In this context, the adding of temperature sensors is not acceptable and the studied methods tend to use sensorless approaches such as observators or parameters estimators like the extended Kalman Filter (EKF). Then the important criteria are reliability, computational cost ad real time implementation.
The use of ekf to estimate the transient thermal behaviour of induction motor...Mellah Hacene
This document summarizes a journal article that examines using an Extended Kalman Filter (EKF) to estimate the transient thermal behavior of an induction motor drive without sensors. It first reviews common thermal modeling methods for induction motors, including simple, finite element, and electrical equivalent circuit models. It then presents the authors' thermal model of the induction motor in state-space form, incorporating linear relationships between resistance and temperature, power losses, heat transfer, and temperature rise in the stator and rotor. The resulting state equations can be used by the EKF for sensorless estimation of temperatures and resistances.
Cascade forward neural network based on resilient backpropagation for simulta...Mellah Hacene
Cascade-Forward Neural Network Based on Resilient Backpropagation for Simultaneous Parameters and State Space Estimations of Brushed DC Machines
Advances in Modelling and Analysis B
PID Controller Design for a Real Time Ball and Beam System – A Double Integra...idescitation
In this paper, the authors have discussed and shown
how to tune the PID controller in closed loop with time-delay
for the double integrator systems for a particular stability
margins. In math model it is assumed that time delay (ô) of
the plant is known. As a case study the authors have consid-
ered the mathematical model of the real-time beam and ball
system and analyzed the simulation and real time response.
Pwm Control Strategy for Controlling Of Parallel Rectifiers In Single Phase T...IJERA Editor
This paper explains that how to develop and design, control of single phase to three phase drive system. The
proposed topology of drive system consisting of two parallel connected rectifiers, inverter and induction motor,
connected through inductor and capacitor, where used to produce balanced output to the motor drive. The main
objective of this proposed method is to reduce the circulating currents and harmonic distortions at the converter
input side, here the control strategy of drive system is PWM (pulse width modulations techniques) control
strategy, the proposed topology also provides fault compensation in the case of short circuit faults and failure of
switches for uninterrupted Power supplies. We also develop and simulate the MATLAB models for proposed
drive system, by using MATLAB/ Simulink the output results simulate and observed.
MODELLING AND SIMULATION OF INVERTED PENDULUM USING INTERNAL MODEL CONTROLJournal For Research
The internal model control (IMC) philosophy relies on the internal model principle, which states that control can be achieved only if the control system encapsulates, either implicitly or explicitly, some representation of the process to be controlled. In particular, if the control scheme is developed based on an exact model of the process, then perfect control is theoretically possible. Transfer function of Inverted Pendulum is selected as the base of design, which examines IMC controller. Matlab/simulink is used to simulate the procedures and validate the performance. The results shows robustness of the IMC and got graded responses when compared with PID. Furthermore, a comparison between the PID and IMC was shows that IMC gives better response specifications.
This document summarizes a research paper that proposes a new control technique for a Doubly Fed Induction Generator (DFG) used in variable speed wind turbines. The technique uses a nonlinear sliding mode control approach with an exponential reaching law (ERL) to control the active and reactive powers generated by the wind turbine. Simulation results show that this sliding mode control with ERL is more robust and improves power quality and stability compared to traditional sliding mode control approaches. It reduces chattering phenomenon while also accelerating the system response for better tracking of the desired control objectives.
This document discusses symmetrical components analysis of unbalanced three-phase power systems. It defines symmetrical components as three balanced systems that a unbalanced three-phase system can be resolved into. It describes how to calculate the positive, negative, and zero sequence components of voltages and currents using phasor transformations. Examples are provided to demonstrate how to calculate symmetrical components for given unbalanced voltage and current values. The document also discusses sequence impedances of transformers and how to model zero sequence networks of different transformer configurations.
Power transformer faults diagnosis using undestructive methods and ann for dg...Mellah Hacene
Power transformer faults diagnosis using undestructive methods (Roger and IEC) and artificial neural network for dissolved gas analysis applied on the functional transformer in the Algerian north-eastern: a comparative study
Bouchaoui Lahcene, Kamel Eddine Hemsas, Hacene Mellah, saad eddine benlahneche
Nowadays, power transformer aging and failures are viewed with great attention in power transmission industry. Dissolved gas analysis (DGA) is classified among the biggest widely used methods used within the context of asset management policy to detect the incipient faults in their earlier stage in power transformers. Up to now, several procedures have been employed for the lecture of DGA results. Among these useful means, we find Key Gases, Rogers Ratios, IEC Ratios, the historical technique less used today Doernenburg Ratios, the two types of Duval Pentagons methods, several versions of the Duval Triangles method and Logarithmic Nomograph. Problem. DGA data extracted from different units in service served to verify the ability and reliability of these methods in assessing the state of health of the power transformer. Aim. An improving the quality of diagnostics of electrical power transformer by artificial neural network tools based on two conventional methods in the case of a functional power transformer at Sétif province in East North of Algeria. Methodology. Design an inelegant tool for power transformer diagnosis using neural networks based on traditional methods IEC and Rogers, which allows to early detection faults, to increase the reliability, of the entire electrical energy system from transport to consumers and improve a continuity and quality of service. Results. The solution of the problem was carried out by using feed-forward back-propagation neural networks implemented in MATLAB-Simulink environment. Four real power transformers working under different environment and climate conditions such as: desert, humid, cold were taken into account. The practical results of the diagnosis of these power transformers by the DGA are presented. Practical value.....
This document summarizes a paper presented at the International Conference on Mechatronics in Kumamoto, Japan in May 2007. The paper presents analysis and implementation of exact model knowledge and direct adaptive control schemes for a 4th order ball and beam system. Two controllers are designed - one using the exact model and one using direct adaptive control. Experimental results show that both controllers can track constant and sinusoidal references for the ball position asymptotically on a physical ball and beam system.
Camless engines eliminate mechanical linkages like camshafts that traditionally open and close intake and exhaust valves. Instead, camless engines use electro-hydraulic or electromechanical systems to provide infinite control over valve timing, lift, and duration. This allows for greater engine efficiency and power. Sensors detect operating conditions and an electronic control unit actuates solenoids and hydraulic systems to optimize valve behavior for each situation. While camless engines are more expensive and complex than traditional designs, their performance advantages are expected to lead to their increased adoption over time.
Sturman engines camless digital engines overview articleSteve Wittrig
Benefits of Sturman’s Camless Engine:
Independent valve lift and timing control allows mixed-charge combustion
Low parasitic loss, since most of the conventional valvetrain (including the camshaft) is eliminated
High-speed engine operation (up to 12,000 rpm)
Enables homogeneous charge compression ignition (HCCI) combustion
Enables cylinder de-activation and cylinder balancing
Scalable to any engine size and can be retrofitted to older engines since all the technology is in the head
Compatible with any fuel type
A square lift pattern compared to the lobe profiles a camshaft requires
Can be used to create an internal EGR system
Promises up to 60 percent thermal efficiency
Can be used to help eliminate the need for an exhaust aftertreatment
Only system able to run the Sturman Combustion Cycle
This document is a seminar report on the Multi Air engine technology developed by Fiat. It discusses the history of the technology's development over 10 years at a cost of over $100 million. The Multi Air system allows variable valve lift and timing on individual cylinders using electro-hydraulic actuation of the intake valves. This precision air control enables improved fuel efficiency, power and emissions compared to conventional engines. Fiat claims the Multi Air technology is a breakthrough that will license to other manufacturers.
The document discusses camless engine technology as an alternative to conventional camshaft-controlled engines. It provides an overview of how camless engines work by directly controlling valve operation electronically rather than mechanically via camshafts. The key components of a camless engine include solenoid valves, hydraulic pumps and accumulators, and electronic control units that precisely time valve opening and closing for improved efficiency over traditional engine designs. Benefits of camless engines include more flexibility and accuracy in valve timing for better fuel economy and power.
This document presents an overview of camless valve systems in engines. It discusses the limitations of traditional camshaft-based systems and introduces two main types of camless systems - electro-mechanical and electro-hydraulic. Electro-mechanical systems use electromagnetic actuators like solenoids to directly open and close valves, allowing for variable valve timing and lift. Electro-hydraulic systems use pressurized hydraulic fluid and actuators controlled by solenoid valves to provide continuously variable control of valve parameters. Camless systems offer benefits like increased fuel efficiency and power but are more complex and expensive than traditional camshaft designs.
The document discusses camless engines, which eliminate mechanical linkages between the camshaft and valves. This allows for infinite variability of valve timing, lift, and duration compared to conventional engines with fixed cam profiles. Camless engines use electro-hydraulic actuators incorporating a hydraulic pendulum mechanism to independently control each valve with a hydraulic fluid-based liquid spring. The electronic control unit processes sensor inputs to command the actuators and optimize performance for factors like fuel efficiency and emissions. While more sophisticated than conventional engines, camless engines are expected to provide benefits like improved fuel economy and power.
CAMLESS ENGINE provide a great development in I C Engine and mark begining of 2nd generation engine...
Further Research and development are needed to take full advantage of the system !!!
This document discusses camless engines. A camless engine uses solenoid actuators instead of a camshaft to open and close valves. It describes the basic 4-stroke cycle of a camless engine involving intake, compression, combustion, and exhaust. It also discusses two methods for actuating the valves electronically without a camshaft: using electro-mechanical rotary solenoid actuators controlled by a microcontroller or a hydraulic system with an electrically operated hydraulic valve. The main sensors used in a camless engine are the engine load sensor, exhaust gas sensor, valve position sensor, and engine speed sensor.
Camless engine by Royal Madan & Vivek KumarRoyal Madan
The document discusses the development and benefits of a camless engine. A camless engine uses electromagnetic, hydraulic, or pneumatic actuators instead of a camshaft to open the engine valves. This allows for truly variable valve timing in each engine cycle. The document describes two main types of camless systems - electromechanical and electrohydraulic. An electromechanical system uses solenoid actuators controlled by a microcontroller to open the valves. An electrohydraulic system uses electrically controlled hydraulic valves and actuators. Simulation results show the camless engine improves fuel economy by up to 6.5% compared to existing cam-based systems, while producing more torque.
Camless engines eliminate mechanical linkages between the crankshaft and valves, allowing for infinite variability of valve timing, lift, and duration. Sensors monitor engine parameters and send signals to an ECU, which controls actuators to vary the valves as needed. This electrohydraulic camless system uses compressed hydraulic fluid and a hydraulic pendulum mechanism to accelerate and decelerate the valves independently according to requirements. Camless engines provide benefits like improved fuel efficiency, higher power and torque, and reduced size and weight compared to conventional camshaft engines. However, they also have disadvantages including added complexity and costs. Overall, camless valve technologies are expected to replace conventional camshaft designs in the future.
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Art is a creative expression that stimulates the senses or imagination according to Felicity Hampel. Picasso believed that every child is an artist but growing up can stop that creativity. Aristotle defined art as anything requiring a maker and not being able to create itself.
Passivity Based Control for PV Applications by Using a Buck Power Converter
The use of power converters for everyday applications is becoming more and more important. Current technological applications simultaneously demand a high level of precision and performance, so DC-DC converters have a very important role in systems requiring energy level conversion and adaptation. As part of the work of this paper, we are interested in an analysis of modeling and control law synthesis approaches to ensure stability and a certain level of performance in the entire operating domain. The objective of our research work is therefore to propose a control law whose synthesis is based on a formalized (modeling & control) approach with a view to obtaining a control law adapted to the operating point. The principles used are based on the control and observation by the theory of passivity for the synthesis of control law of buck power converter for PV Applications.
In this paper, a three-phase load connected to a NPC three-level inverter is presented. To generate gate signals for the multilevel inverter, two commands are developed and compared: the phase disposition pulse width modulation (PDPWM) and the space vector pulse width modulation (SVPWM). DC supply is provided by photovoltaic cells. Boost converter controls the power transfer from photovoltaic generator. Due to nonlinear I-V characteristics of photovoltaic cells, a maximum power point tracking algorithm is adopted to maximize the output power, the nonlinear controller (sliding mode) is developed and simulated. To verify the effectivnesse of the introdueced controller, it is compared with the fuzzy logic controller. Matlab-simulink is used for simulation, analysis and interpretation the results of these controllers.
This document summarizes a research paper that proposes a new sliding mode controller to control a buck converter for maximum power point tracking in photovoltaic applications. A block diagram of the proposed system is presented, including a buck converter, sliding mode controller, and battery. The theoretical background of photovoltaic modeling, sliding mode control surfaces, and buck converters is then explained. Simulation results showed that the sliding mode controller was able to track and achieve maximum power under varying temperature and irradiance conditions. The conclusion discusses potential improvements like adding a real-time clock to automate the system and notes applications for powering remote areas.
Comparison of backstepping, sliding mode and PID regulators for a voltage inv...IJECEIAES
In the present paper, an efficient and performant nonlinear regulator is designed for the control of the pulse width modulation (PWM) voltage inverter that can be used in a standalone photovoltaic microgrid. The main objective of our control is to produce a sinusoidal voltage output signal with amplitude and frequency that are fixed by the reference signal for different loads including linear or nonlinear types. A comparative performance study of controllers based on linear and non-linear techniques such as backstepping, sliding mode, and proportional integral derivative (PID) is developed to ensure the best choice among these three types of controllers. The performance of the system is investigated and compared under various operating conditions by simulations in the MATLAB/Simulink environment to demonstrate the effectiveness of the control methods. Our investigation shows that the backstepping controller can give better performance than the sliding mode and PID controllers. The accuracy and efficiency of the proposed backstepping controller are verified experimentally in terms of tracking objectives.
Iaetsd design of a robust fuzzy logic controller for a single-link flexible m...Iaetsd Iaetsd
This document describes the design of a fuzzy logic controller for a single-link flexible manipulator. A fuzzy-PID controller is used to control an uncertain flexible robotic arm and its internal motor dynamics parameters. The controller is tested against conventional integral and PID controllers in simulations. The results show the proposed fuzzy PID controller has better robustness under variations in motor dynamics compared to the other controllers.
This paper investigated the performance of the sliding mode control technique for dc/dc converter using frequency response method. The applications of the step down type switching regulator) buck converter (are found in the devices that use batteries as power source like laptop, cell phones, electric vehicle, and recently, it has also been used in the renewable energy processing, as a maximum output power can be achieved at higher efficiency. In order to optimize the efficiency and for convenient power management, the issues like power on transients, the effect of load variation, Switching and Electromagnetic interference (EMI) losses has to be overcome for which controllers are used. In the proposed method, pulse width modulation (PWM) based on proportional-integral-derivative sliding mode voltage controller (PID SMVC) is designed for a buck converter and the response for appropriate control parameters has been obtained. The system stability has been examined and analyzed from the performance characteristics, which shows clearly that the buck converter controlled by the sliding mode controller has fast dynamic response and it’s very efficient for various applications.
Body travel performance improvement of space vehicle electromagnetic suspensi...Mustefa Jibril
Electromagnetic suspension system (EMS) is mostly used in the field of high-speed vehicle. In this paper, a space exploring vehicle quarter electromagnetic suspension system is modelled, designed and simulated using linear quadratic optimal control problem. Linear quadratic Gaussian and linear quadratic integral controllers are designed to improve the body travel of the vehicle using bump road profile. Comparison between the proposed controllers is done and a promising simulation result have been analyzed.
Total Harmonic Distortion of Dodecagonal Space Vector ModulationIJPEDS-IAES
Space vector modulation technique is one of the best PWM techniques which have been implemented to the Multilevel inverter circuit to get the purely sinusoidal cuurent. This is a important algorithm which is implemented in open wind induction motor. This type of I.M has great impact on Electric Drive system. SVM is nothing but the technique of switching algorithm. The Hexagonal space vector modulation has been implemented before, but elimination of higher order harmonics is not possible. Torque pulsation arises. Speed control of Induction motor was not smooth. So Dodecagonal (12) structure developed. A 12 side polygonal space vector structure is meant for eliminating (6n±1) harmonics in the phase current waveform throughout the modulating range. A high resolution of PWM technique is proposed involving multiple 12 sided polygonal (Dodecagonal) structure that can generate highly sinusoidal voltage at a reduced switching frequency. In this paper different values of frequencies have been taken for harmonic analysis. SVM method features a higher level of dc-bus voltage utilization compared to the conventional PWM.
Adaptive terminal sliding mode control strategy for dc–dc buck convertersISA Interchange
This document presents an adaptive terminal sliding mode control (ATSMC) strategy for DC-DC buck converters. The strategy uses terminal sliding mode control (TSMC) to ensure finite time convergence of output voltage errors to equilibrium, and integrates an adaptive law to make the sliding line dynamic during load variations. Simulation and experimental results show the ATSMC exhibits faster output voltage response during load changes compared to conventional SMC and TSMC strategies.
Adaptive terminal sliding mode control strategy for DC–DC buck convertersISA Interchange
This document presents an adaptive terminal sliding mode control (ATSMC) strategy for DC-DC buck converters. The strategy uses terminal sliding mode control (TSMC) to provide finite time convergence of output voltage errors to equilibrium during load variations. An adaptive law is integrated into the TSMC to make the sliding line dynamic. Simulation and experimental results show the ATSMC exhibits faster output voltage response during load changes compared to conventional sliding mode control and TSMC. The influence of controller parameters like the fractional power used in the sliding function on startup and transient response is also analyzed.
This document summarizes a numerical study of airflow over an Ahmed body using RANS turbulence models. It finds that the k-ε-v2 model more accurately predicts separation and reattachment compared to other models. The study simulates flow over an Ahmed body with a 35 degree rear angle using various turbulence models and investigates the effects of grid layout and differencing schemes on the results. Numerical results agree well with experimental data on the wake structure and turbulent kinetic energy distribution behind the body.
17.pmsm speed sensor less direct torque control based on ekfMouli Reddy
This document presents a speed sensorless direct torque control method for permanent magnet synchronous motors (PMSM) using an Extended Kalman Filter (EKF). The EKF is used to estimate the stator flux linkage and rotor speed without needing a mechanical speed sensor. This overcomes issues with traditional direct torque control methods like large current and flux ripples. Simulation results show the EKF method maintains the fast torque response of direct torque control while improving dynamic and static performance and robustness to parameter and load variations compared to traditional methods.
In this paper, a new approach is proposed for keeping the RMS voltage output constant, the system is supplying by a self-excited induction generator (SEIG) driven by a controlled DC motor with variable speed and load. The scheme used in this paper is based on a classical Proportional-Integral regulator wich controls a SPWM switching. A MATLAB Simulink model of the system is developed to maintain the AC voltage at the desired value. Then a comparison is examined between simulation and experimental results using dSPACE board. The results are provided to verify the effectiveness of this approach and it gives very high performance.
This document describes using active disturbance rejection control (ADRC) for controlling a single-stage photovoltaic system connected to the electrical grid. It compares ADRC to the conventional perturb and observe (P&O) control method. ADRC combined with incremental conductance (ADRC-IC) is used for maximum power point tracking (MPPT) control. ADRC is also used to control the inverter to regulate the DC bus voltage and ensure unity power factor injection into the grid. The system aims to maximize power extraction from the PV array and regulate power injection into the grid with low harmonics.
This document proposes a digital state feedback control method for current control of parallel DC-DC converters. It derives the digital state feedback controller structures for both continuous and discrete time domains using a pole placement technique. This allows precise current sharing among converter modules while meeting performance specifications. It provides examples applying this control scheme to a bidirectional converter for a 42V/14V automotive system in continuous time and a parallel buck converter in discrete time. Both examples are implemented on a DSP to verify the proposed control method.
This document discusses the performance of hybrid intelligent controllers for load frequency control in multi-area interconnected power systems. It compares the performance of adaptive neuro-fuzzy inference system (ANFIS), artificial neural network (ANN), fuzzy, PI, and PID controllers. ANFIS combines the advantages of fuzzy systems and ANN's quick response and adaptability. The document finds that ANFIS has superior performance over ANN, fuzzy, PI, and PID controllers for a 1% step load variation based on simulations in MATLAB/Simulink of a four area hydro-thermal power system.
Output feedback trajectory stabilization of the uncertainty DC servomechanism...ISA Interchange
This work proposes a solution for the output feedback trajectory-tracking problem in the case of an uncertain DC servomechanism system. The system consists of a pendulum actuated by a DC motor and subject to a time-varying bounded disturbance. The control law consists of a Proportional Derivative controller and an uncertain estimator that allows compensating the effects of the unknown bounded perturbation. Because the motor velocity state is not available from measurements, a second-order sliding-mode observer permits the estimation of this variable in finite time. This last feature allows applying the Separation Principle. The convergence analysis is carried out by means of the Lyapunov method. Results obtained from numerical simulations and experiments in a laboratory prototype show the performance of the closed loop system.
In this paper, a new sliding mode controller is proposed as the indirect control method and compared to a simple direct control method in order to control a buck converter in photovoltaic applications. The solar arrays are dependent power sources with nonlinear voltage-current characteristics under different environmental conditions. From this point of view, the DC/DC converter is particularly suitable for the application of the sliding mode control in photovoltaic application, because of its controllable states. Solar tracking allows more energy to be produced because the solar array is able to remain aligned to the sun. This method has the advantage that it will guarantee the maximum output power possible by the array configuration. Problems and possible improvements will also be presented.
On the dynamic behavior of the current in the condenser of a boost converter ...TELKOMNIKA JOURNAL
In this paper, an analytical and numerical study is conducted on the dynamics of the current in the condenser of a boost converter controlled with ZAD, using a pulse PWM to the symmetric center. A stability analysis of periodic 1T-orbits was made by the analytical calculation of the eigenvalues of the Jacobian matrix of the dynamic system, where the presence of flip and Neimar–Sacker-type bifurcations was determined. The presence of chaos, which is controlled by ZAD and FPIC techniques, is shown from the analysis of Lyapunov exponents.
This document presents a second order integral sliding mode control approach for speed control of a DC motor system. The DC motor system is modeled as a second order system with uncertainty and disturbances. Three controllers are designed and compared - a second order integral sliding mode controller, a conventional sliding mode controller, and a PID controller. Simulation results show that the proposed second order integral sliding mode controller has the fastest response time, no overshoot, smooth control input, and drives the sliding surface to zero, performing better than the other controllers in terms of robustness and disturbance rejection.
This document outlines the syllabus, study, and evaluation scheme for various Bachelor of Technology programs including Mechanical Engineering, Production Engineering, Industrial and Production Engineering, and Mechanical and Industrial Engineering at the U.P. Technical University in Lucknow, India. It provides the course codes, subjects, credit hours, theory and practical class periods, evaluation criteria for sessional and semester exams, and other details for each semester of study from the second to sixth semester. Departmental electives and audit courses on human values and professional ethics are also included.
Nano batteries are batteries fabricated using nanotechnology. They have electrodes made of nanomaterials which allows lithium ions to move faster between electrodes during charging and discharging compared to conventional lithium-ion batteries. This enables nano batteries to charge and discharge more quickly. Additionally, the use of nanomaterials prevents the formation of a solid electrolyte interface barrier that conventional batteries experience at high temperatures. Nano batteries could potentially be used in applications like electronics, defense, aerospace, industrial, and healthcare due to their faster charging capabilities and ability to operate at higher temperatures than conventional lithium-ion batteries.
This document discusses the working principles of hydraulic lifts and presses. Hydraulic lifts use high-pressure liquid to lift passengers or goods between floors in multi-story buildings. Hydraulic presses apply Pascal's law to lift heavy weights using smaller applied forces. Hydraulic lifts consist of a fixed cylinder, cage, and sliding ram, while presses have two connected cylinders of different sizes. When fluid under pressure is forced into the cylinders, the rams or plungers are pushed upward to lift the load. Hydraulic systems allow heavy loads to be lifted efficiently using incompressible fluids and smaller input forces.
This document discusses the working principles of hydraulic lifts and presses. It explains that hydraulic lifts use high-pressure liquid to lift passengers or goods between floors in multi-story buildings. Hydraulic presses also use high fluid pressure to lift heavy weights using a much smaller applied force, based on Pascal's law that pressure in a fluid is transmitted equally in all directions. The document then provides details on the components and operating mechanisms of both hydraulic lifts and presses.
This document discusses thermodynamic properties of fluids, including:
1) Derivations of equations relating the primary thermodynamic properties of pressure, volume, temperature, internal energy, and entropy for homogeneous phases and fluids.
2) Calculations of changes in enthalpy, entropy, and internal energy based on changes in pressure and temperature.
3) The thermodynamic properties of Gibbs energy and residual properties.
4) An example problem calculating the enthalpy and entropy of saturated isobutane vapor at a specified temperature and pressure using compressibility factor and ideal gas heat capacity data.
The document describes boilers and their two main types. A boiler is a vessel that heats water under pressure using a fuel source, and the steam or hot fluid is used for heating or industrial processes. Boilers are either fire tube, where combustion gases pass through tubes to heat the water, or water tube, where water passes through tubes surrounded by exhaust gases heating the tube surfaces. The goal of both types is to maximize heat transfer between water and hot gases.
This document provides information about the key components and processes involved in a steam power plant. It discusses the essential equipment needed like the furnace, boiler, turbine, and piping system. It also describes the main circuits for feed water/steam, coal/ash, air/gas, and cooling water. The document outlines the basic Rankine cycle used in steam power plants and lists the common types of components used.
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
ACEP Magazine edition 4th launched on 05.06.2024Rahul
This document provides information about the third edition of the magazine "Sthapatya" published by the Association of Civil Engineers (Practicing) Aurangabad. It includes messages from current and past presidents of ACEP, memories and photos from past ACEP events, information on life time achievement awards given by ACEP, and a technical article on concrete maintenance, repairs and strengthening. The document highlights activities of ACEP and provides a technical educational article for members.
Comparative analysis between traditional aquaponics and reconstructed aquapon...bijceesjournal
The aquaponic system of planting is a method that does not require soil usage. It is a method that only needs water, fish, lava rocks (a substitute for soil), and plants. Aquaponic systems are sustainable and environmentally friendly. Its use not only helps to plant in small spaces but also helps reduce artificial chemical use and minimizes excess water use, as aquaponics consumes 90% less water than soil-based gardening. The study applied a descriptive and experimental design to assess and compare conventional and reconstructed aquaponic methods for reproducing tomatoes. The researchers created an observation checklist to determine the significant factors of the study. The study aims to determine the significant difference between traditional aquaponics and reconstructed aquaponics systems propagating tomatoes in terms of height, weight, girth, and number of fruits. The reconstructed aquaponics system’s higher growth yield results in a much more nourished crop than the traditional aquaponics system. It is superior in its number of fruits, height, weight, and girth measurement. Moreover, the reconstructed aquaponics system is proven to eliminate all the hindrances present in the traditional aquaponics system, which are overcrowding of fish, algae growth, pest problems, contaminated water, and dead fish.
Optimizing Gradle Builds - Gradle DPE Tour Berlin 2024Sinan KOZAK
Sinan from the Delivery Hero mobile infrastructure engineering team shares a deep dive into performance acceleration with Gradle build cache optimizations. Sinan shares their journey into solving complex build-cache problems that affect Gradle builds. By understanding the challenges and solutions found in our journey, we aim to demonstrate the possibilities for faster builds. The case study reveals how overlapping outputs and cache misconfigurations led to significant increases in build times, especially as the project scaled up with numerous modules using Paparazzi tests. The journey from diagnosing to defeating cache issues offers invaluable lessons on maintaining cache integrity without sacrificing functionality.
Use PyCharm for remote debugging of WSL on a Windo cf5c162d672e4e58b4dde5d797...shadow0702a
This document serves as a comprehensive step-by-step guide on how to effectively use PyCharm for remote debugging of the Windows Subsystem for Linux (WSL) on a local Windows machine. It meticulously outlines several critical steps in the process, starting with the crucial task of enabling permissions, followed by the installation and configuration of WSL.
The guide then proceeds to explain how to set up the SSH service within the WSL environment, an integral part of the process. Alongside this, it also provides detailed instructions on how to modify the inbound rules of the Windows firewall to facilitate the process, ensuring that there are no connectivity issues that could potentially hinder the debugging process.
The document further emphasizes on the importance of checking the connection between the Windows and WSL environments, providing instructions on how to ensure that the connection is optimal and ready for remote debugging.
It also offers an in-depth guide on how to configure the WSL interpreter and files within the PyCharm environment. This is essential for ensuring that the debugging process is set up correctly and that the program can be run effectively within the WSL terminal.
Additionally, the document provides guidance on how to set up breakpoints for debugging, a fundamental aspect of the debugging process which allows the developer to stop the execution of their code at certain points and inspect their program at those stages.
Finally, the document concludes by providing a link to a reference blog. This blog offers additional information and guidance on configuring the remote Python interpreter in PyCharm, providing the reader with a well-rounded understanding of the process.
Redefining brain tumor segmentation: a cutting-edge convolutional neural netw...IJECEIAES
Medical image analysis has witnessed significant advancements with deep learning techniques. In the domain of brain tumor segmentation, the ability to
precisely delineate tumor boundaries from magnetic resonance imaging (MRI)
scans holds profound implications for diagnosis. This study presents an ensemble convolutional neural network (CNN) with transfer learning, integrating
the state-of-the-art Deeplabv3+ architecture with the ResNet18 backbone. The
model is rigorously trained and evaluated, exhibiting remarkable performance
metrics, including an impressive global accuracy of 99.286%, a high-class accuracy of 82.191%, a mean intersection over union (IoU) of 79.900%, a weighted
IoU of 98.620%, and a Boundary F1 (BF) score of 83.303%. Notably, a detailed comparative analysis with existing methods showcases the superiority of
our proposed model. These findings underscore the model’s competence in precise brain tumor localization, underscoring its potential to revolutionize medical
image analysis and enhance healthcare outcomes. This research paves the way
for future exploration and optimization of advanced CNN models in medical
imaging, emphasizing addressing false positives and resource efficiency.
2. m2m1k1k3k2b3b1b2Fy1y2Spring 1Spring 2Solenoid 1Solenoid 2Armature00d1d2m2m1k1k3k2b3b1b2Fy1y2Spring 2Armature00d1d2
Figure 1. Schematic Diagram of EMCV System
Figure 2. Comparison between Ideal Correlation and Measured Data
The inductance of the coil was measured with the following procedure. At first, the two springs are removed and the armature is held at the armature seating position, i.e. y1 = -d1. The frequency response from voltage to current is measured by sinusoidal signal sweep. The magnitude of the excitation signal is limited to be small. The frequency response was then fit by a first-order model shown in (2). The fitted curve matches with the measured data in the sense of having the same static gain and 3dB frequency. Then the system is resembled and the armature is held such that the engine valve is at the mid-opening (equilibrium) position, i.e. y1 = 0. The frequency response from voltage to current is measured again by using the same method. The advantage of this method is that it avoids measuring force and short distance, which are difficult to gauge accurately. In addition, the values of L(-d1) and L(0) are different in magnitudes due to the nonlinearity of the system inductance, which leads to a precise measurement of air gap, g.
In the EMCV seating control, the nominal electromagnetic force for seating control is less than the spring force when the valve lift is relatively large. However, as the valve lift gets smaller and smaller, the electromagnetic force will get closer and closer to the spring force, and eventually totally balance the spring force and hold the valve at the seating position. Since almost-zero valve velocity at seating position is our control target, the system should be linearized around seating position, zero velocity and with holding current. The discrepancy between the non-saturation model and the measured data along the equilibrium points are quite significant, which indicates that equation (5) does not hold any longer for linearizing the system around seating position, zero velocity and with holding current.
To solve this problem, equation (5) is modified to reflect the effect of flux linkage saturation. See equation (6).
Based on the measurements, we may calculate g and L0 by using equations (3) and (4). Table 1 lists the identified and calculated parameters in these tests.
201211(,) 2()magLgiFydg ρ=− ++
i y (6)
0(1
) LLd=− (3)
By differentiating equation (6), we have
11(0) ()(0) LgdLdL= −− (4)
112magdFGdyGdi=⋅+⋅ (7)
where
2011211111(,)1(,) ()2LgiiyiyGydgydgy ρρ 1 ∂ =− ⋅ ++++∂ (8)
Table 1. Identified Parameters from Inductance Measurements
L(-d1) (H)
1.25
L(0) (H)
0.0770
L0 (H)
1.25
g (mm)
0.256
0121211(,)(,) ()2LgiiiyGiyydgi ρρ ∂=−+⋅++∂ (9)
The current-force relationship is, without consideration of the saturation of magnetic flux linkage, governed by the equation (5).
202112()magLgiFydg=− ++ (5)
For small-signal linearization around y1 = y1*, y2 = y2* and i = i*, the transfer functions from current to armature and valve positions are shown in (10). Interested readers could refer to the author’s previous paper [6] for detailed derivation. 2*2232322212*211212122323222()() (()())(()())() msbbskkGdibskdYmsbbskkGmsbbskkbskdY ++++ ⋅⋅+=++++−++++−+ 2
(10)
In the next test, the armature is held at different locations by balancing the spring force with electromagnetic force. The spring force can be calculated from the spring constants and valve lift when the actuator is held still. The measured points are drawn on Figure 2 as well as equation (5).
The transfer function from current to valve position can be rewritten as
22143243211dYBsdiAsAsAsAsA+ =
0 ++++ (11)
3114
Proceedings of the American Control Conference
Denver, Colorado June 4-6, 2003
3. where ** 1*212114* *** 201(,) () (,) 2iymmydgAikLgiiyi ρρ ++ =− ∂ +⋅ ∂ (12)
[] ** 1*2111232123* *** 201(,) ()()( (,) 2iyydgmbbmbbAikLgiiyi ρρ +++++ =− ∂ +⋅∂
) (13) ** 1** 1*2112* *** 201(,) 1232*** 01212*2* 11111(,) 212232() (,) 2() (,)1 ()2()()- iyiyydgAikLgiiyimkkLgiiymkkydgydgybbbbb ρρρρ ++ =− ∂+⋅∂ ++ ∂⋅+−−⋅ ++++∂ +++
(14) ** 1** 1*2111* *** 201(,) 2*** 0112*2* 11111(,) 22323122() (,) 2(,)1- ()2 ()()()-2iyiyydgAikLgiiyiLgiiykkydgydgybbkkbbb ρρρρ ++ =− ∂ +⋅∂ ∂+− ++++∂⋅ ⋅++++
⋅
(15) ** 1** 1*2110* *** 201(,) 2*** 20112232*2* 11111(,) () (,) 2(,)1- ()- ()2iyiyydgAikLgiiyiLgiiykkkkkydgydgy ρρρρ ++ =− ∂+⋅∂ ∂⋅+−⋅+ ++++∂
(16)
A0, A1, A2, A3 and A4 can be identified by curve-fitting with frequency response test data. There are seven unknown parameters in these equations, , ** 1(,)iyρ ** 1(,)iyi ρ∂ ∂ , ** 11(,)iyy ρ∂ ∂ , b1, b2, b3, k2. Two more equations are needed to solve for the unknown parameters, which are
*2**111312* 02()()(,)ydgkkyiyLgi ρ +++ =−
*1 (17)
(18) 13bbb+=
where b is the damping coefficient identified from the free response test, and F* is the balanced spring force at equilibrium position.
Frequency response tests were conducted on the experimental system to extract the unknown parameters in (10) - (18). The open-loop system is unstable. Therefore, the identification tests had to be conducted on a closed-loop system. Chirp signal was used as the excitation signal. The reason why sinusoidal signal sweep was not used is because of the fact that it takes long time to complete a test with sinusoidal signal sweep, and during that period the temperature of the actuator increases dramatically, which adversely affects the accuracy of the result. Data were recorded around three different armature positions. The regulated positions of these three runs are 0.3, 0.5 and 0.7 mm, respectively. The identified parameters are listed in Table 2.
Table 2. Parameters Identified from Closed-Loop Frequency Response Test
Spring constant k2 (kN/m)
751.6
Damping coefficient, b1 (kg/sec)
0.2
Damping coefficient, b2 (kg/sec)
1.5
Damping coefficient, b3 (kg/sec)
0.2
** 1(,)iyρ
0.092103 ** 11(,)iyy ρ∂ ∂ (m-1)
172.62 ** 1(,)iyi ρ∂ ∂ (A-1)
-0.035199
3. CONTROL DESIGN
The control structure is shown in Figure 3. Gp is the plant model. Gn is a notch filter. Gc is a stabilizing controller. uff0 is a fixed feedforward control sequence tuned offline. uff is the output of a repetitive learning controller. Gcuffufb+ + yref- +GnGpuf(Q, M) Error sequence fromthe previous cycleuff0+ + eGp'
Figure 3. Control Structure
A notch filter (19) is designed to cancel the lightly-damped second-order mode (see Tai and Tsao [7]).
222222323321() 21ssGnsss ζωωζωω ++ = ++ (19)
Ideally, 2ω should be equal to the resonant model 2ω for perfect cancellation. However, in real implementation, 2ω should be set to be a little bit smaller than 2ω for the robustness of design. The importance of having this notch filter is demonstrated in Tai and Tsao [7].
The notch filter needs to be discretized for the experimental implementation. Discretizing the notch filter using bilinear transformation with frequency pre-warping will get rid of the frequency distortion at notch frequency. The formula of bilinear transformation with frequency pre-warping at ω* is shown in (20).
* * * 1* 1tan21 i.e. ()() 1tan2zszTzsCzCszT ωωωω − →⋅ + − →⋅= + (20)
An experimental test was conducted to demonstrate the difference between using bilinear transformation with and without frequency pre-warping at notch frequency for the discretization of notch filter. More oscillatory response showed up in the step
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4. response test when no frequency pre-warping was applied. See Figure 4.
Figure 4. Experimental Demonstration of Frequency Prewarping for Notch Filter Discretization
The relatively large gain variation shown in the modeling process (see Tai and Tsao [8]) tells us that the designed control system should have relative large gain margin. Linear-quadratic optimal control design is chosen for this purpose. Please refer to [8] for the LQ optimal control design in this study. The detail of Feedforward Control Sequence and Trajectory Design is also shown in [8].
The identified plant could vary as system is in operation. It could be affected by certain factors such as temperature. Therefore, the feedforward control sequence tuned offline might need to be updated as the system is running. n-line. A repetitive learning controller was designed for such purpose by following the synthesis algorithm given by Tsao and Tomizuka [10]. Although it was originally formularized for repetitive feedback control design, the algorithm could also be applied for the auto- tuning of feedforward control signal. The closed-loop plant the repetitive learning controller “sees” is
1GnGpGcpGcGnGp⋅ = +⋅⋅ (21)
The learning control for the (i+1)’th cycle is then given by
(22) where {e,1,()(()())ffiffiriukQukkMek+=⋅+⋅⋅ i(k)} is the error sequence from the i’th cycle; {uff,i(k)} is the feedforward control sequence from the i’th cycle; M is a stable invert of the closed-loop plant Gcp with zero phase-error; kr is a gain to adjust the converging speed; Q is a low-pass filter to maintain the robust stability of the repetitive learner controller.
4. EXPERIMENTAL RESULTS
The closing and seating performance of the closed-loop controlled EMCV system can be quantified by using the following indices: Closing Time tc, Seating Tail-Length ts, Valve Seating Velocity vs, and Armature Seating Velocity va. Please refer to [8] for the definitions of these performance indices.
The control design in section 3 was conducted in continuous-time domain. For experimental implementation, the notch filter was discretized by frequency pre-warping at the resonant frequency. The rest of the feedback controller was discretized with bilinear transformation at 20 KHz sampling frequency.
The EMCV system has a natural frequency of 152 Hz. High natural frequency is necessary for fast valve opening and closing in order to operate at high engine speeds.
It does not mean much by just having one good response because the essential problem we had at the beginning was that the system was sensitive to unknown disturbance. (Indeed, even open-loop control could occasionally render us quiet-seating performance at certain engine cycles.) Therefore when we test our control design, the most important thing is to see if we can have good and consistent system responses.
Two hundred sweeps of engine cycle tests were conducted under closed-loop control. The result of this repeatability test is shown in Figure 5 and Figure 6. Statistical analysis results were listed in Figure 7 and
Table 3. The tracking error is less than 20 μm.
Figure 5. Closed-loop Repeatability Test for the EMCV System
Figure 6. Feedback Control with Switching to Open-Loop After Valve Seating
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5. Figure 7. Distribution of Valve Seating Velocity
Table 3. Summary of Seating Control Result
Mean
Std. Dev.
Valve Seating Velocity, vs, (m/s)
0.061
0.028
Armature Seating Velocity, vs, (m/s)
0.278
0.100
Seating Tail-Length, ts, (ms)
1.23
0.32
Closing Time, tc, (ms)
2.80
0.03
The designed feedback controller needs to be switched to open-loop control after the valve hits its seat because after the valve hits its seat, the armature and the valve starts to separate from each other, and so the system behavior will be different. More importantly, later the armature will hit its own seat, and once it hits, the closed-loop system tends to show unfavorable performance or even turn unstable due to the severe variation of the system stiffness caused by the armature seating. See Figure 8.
Figure 8. Feedback Control without Switching to Open-Loop After Valve Seating
It is possible to keep the closed-loop controller on without switching to open-loop control and yet without losing stability after armature and valve separates by using a low-gain feedback controller. This leads to smaller armature seating velocity (0.048 m/s with standard variation of 0.029 m/s) but larger valve seating velocity (0.093 m/s with standard variation of 0.034 m/s). See Figure 9. Since the valve seating is the main source of noise and mechanical wear, this might not be a favorable choice.
Based on the experimental results and analysis, it appears logical to use the high-gain feedback for valve soft seating and switch to the low-gain feedback for the armature soft seating. However, this approach has not been experimentally verified at this time.
Figure 9. Low-Gain Feedback Control
In the next test, a repetitive learning controller was turned on and used to update the feedforward control based on tracking error from previous cycles. The control signal and measured outputs are drawn in Figure 10. The RMS tracking error is shown in Figure 11. The learning controller needs to be turned off after the minimum current value along the seating control trajectory reaches zero, because further iteration might cause the current go negative, which will change the polarity of the system and cause the system to be unstable.
Figure 10. EMCV Learning Control
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6. [9] Tai, C., “Modeling and Control of Camless Engine Valvetrain Systems,” PhD Dissertation, University of California, Los Angeles, August 2002
[10] Tsao, T-C., and Tomizuka, M., “Robust Adaptive and Repetitive Digital Tracking Control and Application to a Hydraulic Servo for Noncircular Machining,” Transactions of ASME, 1994
[11] Wang, Y., Stefanopoulou, A., Haghgooie, M., Kolmanovsky, I., and Hammoud, M. “Modelling of an Electromechanical Valve Actuator for a Camless Engine,” 5th International Symposium on Advanced Vehicle Control, Ann Arbor, Michigan USA, 2000
Figure 11. RMS Tracking Error Through Learning Process
[12] Wang Y., Stefanopoulou A., Peterson K., Megli T.,Haghgooie M., "Modeling and Control of Electromechanical Valve Actuator," SAE Technical Paper 2002-01-1106, Detroit, MI, March 4-7, 2002
5. CONCLUSIONS
Parameter identification was conducted for a linear EMCV actuator model. A feedback controller was designed for stabilizing the actuator by LQR control design methodology. Repetitive learning control was designed to improve tracking performance by cycle-to-cycle learning process. The different control strategies have been demonstrated on experimental systems. Valve seating velocity of 0.061 m/s was achieved in repeatability test with a standard deviation of 0.028 m/s.
ACKNOWLEDGMENT
The authors gratefully thank Ford Research Lab for lending the electromechanical actuator and Visteon for providing the mechanical springs used in this work.
REFERENCES
[1] Butzmann, S., Melbert, J., and Koch, A., “Sensorless Control of Electromagnetic Actuators for Variable Valve Train,” SAE Paper 2000-01-1225
[2] Hoffmann, W., and Stefanopoulou, A., "Valve Position Tracking for Soft Land of Electromechanical Camless Valvetrain," 3rd IFAC Conference Advances in Automotive Control, 2001
[3] Hoffmann, W., and Stefanopoulou, A., "Iterative Learning Control of Electromechanical Camless Valve Actuator," Proceedings of the American Control Conference, Arlington, VA, June 2001
[4] Peterson, K., Stefanopoulou, A., Megli, T., and Haghgooie. M., “Output Observer Based Feedback for Soft Landing of Electromechanical Camless Valvetrain Actuator,” Proc. American Control Conference, Anchorage, AK, May 8-10, 2002
[5] Stubbs, A., “Modeling And Controller Design Of An Electromagnetic Engine Valve,” M.S. Thesis, University of Illinois at Urbana-Champaign, 2000
[6] Tai, C., Stubbs, A. and Tsao, T-C., “Modeling and Controller Design of an Electromagnetic Engine Valve,” Proc. American Control Conference, 2890-2895, Arlington, VA, June 25-27, 2001
[7] Tai, C. and Tsao, T-C., “Quiet Seating Control Design of an Electromagnetic Engine Valve Actuator,” ASME International Mechanical Engineering Congress and Exposition, New York, NY, November 11-16, 2001
[8] Tai, C. and Tsao, T-C., “Control of an Electromechanical Camless Valve Actuator,” Proc. American Control Conference, 262-267, Anchorage, AK, May 8-10, 2002
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