Proceedings of the 2nd Wseas International Conference on Computer Engineering and Applications, Jan 25, 2008
ABSTRACT Economical operation of large scale systems like a power plant depends on the plant oper... more ABSTRACT Economical operation of large scale systems like a power plant depends on the plant operators and their skills. The operators need to know how to operate the plant under different conditions especially in emergency cases. There are some specific training courses ...
Fault detection is one of the most important and challenging issues in engineering application. I... more Fault detection is one of the most important and challenging issues in engineering application. In this article fault detection of Gilan combined cycle power plant is investigated. To do so two neural network structures are applied. The first neural network which is trained by Kalman Filter. The second structure is NARX network which is trained by levenberg-marquardt method. The results obtained show that the neural network has a great capability in fault detection.
Controllers which are designed through traditional methods do not have proper performance due to ... more Controllers which are designed through traditional methods do not have proper performance due to parameters alternation, un-modeled dynamics, modeling error, unknown process and non-linearity of the process which is approximated linear and in some cases result in instability of the system. Hence in most modern controllers, robustness is major design feature. In this article a LQG controller for the Gas Turbine of Gilan combined cycle power plant is designed. This controller has a robust performance against noise and disturbances.
This study examines the performance of a high-temperature solid oxide fuel cell combined with a c... more This study examines the performance of a high-temperature solid oxide fuel cell combined with a conventional recuperative gas turbine (GT-SOFC) plant, as well as the irreversibility within the system. Individual models are developed for each component, based on the first and second laws of thermodynamics. The overall system performance is then analyzed by applying thermodynamic laws for the entire cycle, to evaluate the thermal efficiency and entropy production of the plant. The results of an assessment of the cycle for certain operating conditions are compared with conventional cycles. Further outcomes indicate that increasing the turbine inlet temperature results in decreasing the thermal efficiency of the cycle, whereas it improves the net specific power output. Moreover, an increase in either the turbine inlet temperature or compression ratio leads to a higher rate of entropy generation within the plant. It was found that about 58% of the irreversibility takes place in the combu...
2009 IEEE International Conference on Control Applications, 2009
ABSTRACT In this paper, an approach for constructing a nonlinear estimator for adaptive compensat... more ABSTRACT In this paper, an approach for constructing a nonlinear estimator for adaptive compensation of the Coulomb friction in mechanical control systems is proposed where the Coulomb friction coefficient is unknown but its variation with time is bounded. The design is based on Lyapunov technique and attempts to compensate the frictional force by estimating the Coulomb friction coefficient. It is shown that asymptotic stability of the error dynamics is guaranteed. The major contribution of this paper is an adaptive control law for friction compensation in the system in which the variation of the Coulomb coefficient with time has not any specified frequency. The simulation results confirm the advantages of the proposed approach against the previous methods for a simple single-mass system.
2009 IEEE International Conference on Control Applications, 2009
Abstract Load frequency control (LFC) issue has been one of the major subjects in electric power... more Abstract Load frequency control (LFC) issue has been one of the major subjects in electric power system operation and design. Nowadays, it is becoming much more significant in accordance to increasing size, changing structure and com-plexity of interconnected power systems. ...
2013 IEEE International Conference on Control Applications (CCA), 2013
ABSTRACT Power plants are highly nonlinear systems demand a powerful identification method for pr... more ABSTRACT Power plants are highly nonlinear systems demand a powerful identification method for prediction of their future values or for control applications. In this paper, a generalized predictive controller (GPC) is developed by neural network for application of power plants load-frequency. In this case, the identified model is characterized by nonlinear model structure based on neural network. The control objectives are to maintain the frequency within a desired range in the presence of load disturbance and governor parameters uncertainty. Based on the nonlinear model predictive control (NMPC), a controller is designed, with particular emphasis on an efficient quasi-Newton algorithm. Quasi newton optimization method is considered for update the inverse Hessian matrix for minimization of NMPC criteria. The algorithm is compared with common PID controller for reference tracking and disturbances rejection.
2009 IEEE Symposium on Industrial Electronics & Applications, 2009
ABSTRACT In this paper, temperature control of a batch tank in a glass factory is investigated. I... more ABSTRACT In this paper, temperature control of a batch tank in a glass factory is investigated. In a turbo-generator system a large amount of energy is wasted as thermal energy at the exhaust. Therefore, use of combined heat and power (CHP) systems is highly under attention. In this work a turbo-generator system and a glass factory are considered as a CHP system. Since the hot exhaust gas has emissions which have a bad effect on the quality of molten glass, therefore, the hot exhaust must be used indirectly in melting glass process, so a rotary regenerator is proposed to transfer gas turbine exhaust heat to the inlet air of the glass melting furnace. It is assumed that turbo-generator is operated at full load condition and gas turbine exhaust is directed into rotary regenerator to transfer gas turbine exhaust heat to inlet air of glass furnace. By controlling the speed of the rotary regenerator, the amount of exchanged energy is controlled. An adaptive control strategy, namely, neuro-PID controller is proposed in this paper. The simulation results depict the capabilities of the proposed controller in different working states.
… of the 2nd WSEAS International Conference …, 2008
Economical operation of large scale systems like a power plant depends on the plant operators and... more Economical operation of large scale systems like a power plant depends on the plant operators and their skills. The operators need to know how to operate the plant under different conditions especially in emergency cases. There are some specific training courses ...
Reliability analysis is one of the most important factors for designing and implementing systems ... more Reliability analysis is one of the most important factors for designing and implementing systems in transportation industry. locomotive, as operative motive, is the most important part in this industry. So researchers focus on reliability analysis to improve reliability for increasing performance and reducing operating cost in this system. Among the subsystems of locomotive, propulsion system plays the important role to transmit energy from power supply to traction motors and at the same time is one of the main causes of failure in locomotive. So reliability analysis in this subsystem is much more important than the others. Although fault tree is a strong method for computing reliability and can also find most probable failures in main systems, there are some drawbacks in using it to reliability analysis, such as uncertainty. To omit or at least to reduce this drawback, fuzzy fault tree has been suggested. In addition to the above mentioned issue, two other important factors which c...
In this paper, the sliding-mode principles are used to design a decentralized observer for indust... more In this paper, the sliding-mode principles are used to design a decentralized observer for industrial interconnected systems. In the design progress, the interaction between sub-systems has been considered as external disturbances. Also, some factors such as external disturbances have been considered. In this regard, a new sliding mode observer (SMO) for state estimation of interconnected linear systems with unknown time-varying delay, in the presence of unknown inputs has been presented. In the present work, the design procedure is simplified in comparison with the other similar SMO. With an adequate choice of a Lyapunov-Krasovskii functional, the sufficient conditions are obtained in LMIs terms to guarantee asymptotic stability of the state estimation errors. The effectiveness, simplicity and straight-forwardness of the method are shown by the simulation results for a two area power system.
1998 IEEE International Joint Conference on Neural Networks Proceedings. IEEE World Congress on Computational Intelligence (Cat. No.98CH36227), 1998
ABSTRACT Identification of a class of nonlinear systems by using two neuro-dynamic structures is ... more ABSTRACT Identification of a class of nonlinear systems by using two neuro-dynamic structures is addressed. The capabilities of the proposed structures for representing the class of system considered are shown analytically. Selection criteria for specifying the fixed structural parameters and adaptation laws for updating the adjustable parameters are provided. Numerical simulation results are also provided to illustrate the performance of the proposed structures
Proceedings of the 1998 IEEE International Conference on Control Applications (Cat. No.98CH36104), 1998
ABSTRACT This paper deals with identification of a multi-input multi-output (MIMO) nonlinear turb... more ABSTRACT This paper deals with identification of a multi-input multi-output (MIMO) nonlinear turbogenerator system by using dynamic neural networks. Using an adaptive time delay neural networks, a neuro-dynamic identifier is proposed. The capability of the proposed structure for representing the nonlinear input-output map of the turbogenerator system is shown analytically. The input-output data set is generated by PSCAD/EMTDC package for a turbogenerator system with default parameters. Simulation results reveal that the proposed neuro-dynamic structure is capable of successfully identifying a highly nonlinear turbogenerator system without any a priori information about the nonlinearities of the system and without any off-line training
Proceedings of 35th IEEE Conference on Decision and Control, 1996
ABSTRACT A simple method for constructing a nonlinear estimator for adaptive friction compensatio... more ABSTRACT A simple method for constructing a nonlinear estimator for adaptive friction compensation is developed. The design is based on Lyapunov technique and attempts to compensate for frictional force by estimating the unknown Coulomb friction coefficient. It is shown that asymptotic stability of the error dynamics is guaranteed without imposing a constraint on the velocity. Simulation results confirm the advantages of the proposed method
2007 International Conference on Intelligent and Advanced Systems, 2007
Arash Mehrafrooz, Alireza Yazdizadeh Dept. of Electrical Engineering, Power and Water University ... more Arash Mehrafrooz, Alireza Yazdizadeh Dept. of Electrical Engineering, Power and Water University of Technology, PO Box 16765-1719, Tehran, Iran arashmehrafrooz@yahoo.com, aryazdizadeh@yahoo.com ... Keywords: Adaptive Control, Smith Rule, Dead-Time Loop, ...
2006 IEEE Conference on Robotics, Automation and Mechatronics, 2006
Abstract Wheeled mobile robots are considered as the most widely used class of mobile robots. Thi... more Abstract Wheeled mobile robots are considered as the most widely used class of mobile robots. This is due to their fast maneuvering, simple controllers, and energy saving characteristics. A new adaptive algorithm for tracking control of these robots is presented in this paper which is robust against external and internal disturbances. A combination of model reference adaptive control and gain scheduling is used to control the robot motion. The simulation results indicate that the designed controller will preserve the robot on its ...
Proceedings of the 2nd Wseas International Conference on Computer Engineering and Applications, Jan 25, 2008
ABSTRACT Economical operation of large scale systems like a power plant depends on the plant oper... more ABSTRACT Economical operation of large scale systems like a power plant depends on the plant operators and their skills. The operators need to know how to operate the plant under different conditions especially in emergency cases. There are some specific training courses ...
Fault detection is one of the most important and challenging issues in engineering application. I... more Fault detection is one of the most important and challenging issues in engineering application. In this article fault detection of Gilan combined cycle power plant is investigated. To do so two neural network structures are applied. The first neural network which is trained by Kalman Filter. The second structure is NARX network which is trained by levenberg-marquardt method. The results obtained show that the neural network has a great capability in fault detection.
Controllers which are designed through traditional methods do not have proper performance due to ... more Controllers which are designed through traditional methods do not have proper performance due to parameters alternation, un-modeled dynamics, modeling error, unknown process and non-linearity of the process which is approximated linear and in some cases result in instability of the system. Hence in most modern controllers, robustness is major design feature. In this article a LQG controller for the Gas Turbine of Gilan combined cycle power plant is designed. This controller has a robust performance against noise and disturbances.
This study examines the performance of a high-temperature solid oxide fuel cell combined with a c... more This study examines the performance of a high-temperature solid oxide fuel cell combined with a conventional recuperative gas turbine (GT-SOFC) plant, as well as the irreversibility within the system. Individual models are developed for each component, based on the first and second laws of thermodynamics. The overall system performance is then analyzed by applying thermodynamic laws for the entire cycle, to evaluate the thermal efficiency and entropy production of the plant. The results of an assessment of the cycle for certain operating conditions are compared with conventional cycles. Further outcomes indicate that increasing the turbine inlet temperature results in decreasing the thermal efficiency of the cycle, whereas it improves the net specific power output. Moreover, an increase in either the turbine inlet temperature or compression ratio leads to a higher rate of entropy generation within the plant. It was found that about 58% of the irreversibility takes place in the combu...
2009 IEEE International Conference on Control Applications, 2009
ABSTRACT In this paper, an approach for constructing a nonlinear estimator for adaptive compensat... more ABSTRACT In this paper, an approach for constructing a nonlinear estimator for adaptive compensation of the Coulomb friction in mechanical control systems is proposed where the Coulomb friction coefficient is unknown but its variation with time is bounded. The design is based on Lyapunov technique and attempts to compensate the frictional force by estimating the Coulomb friction coefficient. It is shown that asymptotic stability of the error dynamics is guaranteed. The major contribution of this paper is an adaptive control law for friction compensation in the system in which the variation of the Coulomb coefficient with time has not any specified frequency. The simulation results confirm the advantages of the proposed approach against the previous methods for a simple single-mass system.
2009 IEEE International Conference on Control Applications, 2009
Abstract Load frequency control (LFC) issue has been one of the major subjects in electric power... more Abstract Load frequency control (LFC) issue has been one of the major subjects in electric power system operation and design. Nowadays, it is becoming much more significant in accordance to increasing size, changing structure and com-plexity of interconnected power systems. ...
2013 IEEE International Conference on Control Applications (CCA), 2013
ABSTRACT Power plants are highly nonlinear systems demand a powerful identification method for pr... more ABSTRACT Power plants are highly nonlinear systems demand a powerful identification method for prediction of their future values or for control applications. In this paper, a generalized predictive controller (GPC) is developed by neural network for application of power plants load-frequency. In this case, the identified model is characterized by nonlinear model structure based on neural network. The control objectives are to maintain the frequency within a desired range in the presence of load disturbance and governor parameters uncertainty. Based on the nonlinear model predictive control (NMPC), a controller is designed, with particular emphasis on an efficient quasi-Newton algorithm. Quasi newton optimization method is considered for update the inverse Hessian matrix for minimization of NMPC criteria. The algorithm is compared with common PID controller for reference tracking and disturbances rejection.
2009 IEEE Symposium on Industrial Electronics & Applications, 2009
ABSTRACT In this paper, temperature control of a batch tank in a glass factory is investigated. I... more ABSTRACT In this paper, temperature control of a batch tank in a glass factory is investigated. In a turbo-generator system a large amount of energy is wasted as thermal energy at the exhaust. Therefore, use of combined heat and power (CHP) systems is highly under attention. In this work a turbo-generator system and a glass factory are considered as a CHP system. Since the hot exhaust gas has emissions which have a bad effect on the quality of molten glass, therefore, the hot exhaust must be used indirectly in melting glass process, so a rotary regenerator is proposed to transfer gas turbine exhaust heat to the inlet air of the glass melting furnace. It is assumed that turbo-generator is operated at full load condition and gas turbine exhaust is directed into rotary regenerator to transfer gas turbine exhaust heat to inlet air of glass furnace. By controlling the speed of the rotary regenerator, the amount of exchanged energy is controlled. An adaptive control strategy, namely, neuro-PID controller is proposed in this paper. The simulation results depict the capabilities of the proposed controller in different working states.
… of the 2nd WSEAS International Conference …, 2008
Economical operation of large scale systems like a power plant depends on the plant operators and... more Economical operation of large scale systems like a power plant depends on the plant operators and their skills. The operators need to know how to operate the plant under different conditions especially in emergency cases. There are some specific training courses ...
Reliability analysis is one of the most important factors for designing and implementing systems ... more Reliability analysis is one of the most important factors for designing and implementing systems in transportation industry. locomotive, as operative motive, is the most important part in this industry. So researchers focus on reliability analysis to improve reliability for increasing performance and reducing operating cost in this system. Among the subsystems of locomotive, propulsion system plays the important role to transmit energy from power supply to traction motors and at the same time is one of the main causes of failure in locomotive. So reliability analysis in this subsystem is much more important than the others. Although fault tree is a strong method for computing reliability and can also find most probable failures in main systems, there are some drawbacks in using it to reliability analysis, such as uncertainty. To omit or at least to reduce this drawback, fuzzy fault tree has been suggested. In addition to the above mentioned issue, two other important factors which c...
In this paper, the sliding-mode principles are used to design a decentralized observer for indust... more In this paper, the sliding-mode principles are used to design a decentralized observer for industrial interconnected systems. In the design progress, the interaction between sub-systems has been considered as external disturbances. Also, some factors such as external disturbances have been considered. In this regard, a new sliding mode observer (SMO) for state estimation of interconnected linear systems with unknown time-varying delay, in the presence of unknown inputs has been presented. In the present work, the design procedure is simplified in comparison with the other similar SMO. With an adequate choice of a Lyapunov-Krasovskii functional, the sufficient conditions are obtained in LMIs terms to guarantee asymptotic stability of the state estimation errors. The effectiveness, simplicity and straight-forwardness of the method are shown by the simulation results for a two area power system.
1998 IEEE International Joint Conference on Neural Networks Proceedings. IEEE World Congress on Computational Intelligence (Cat. No.98CH36227), 1998
ABSTRACT Identification of a class of nonlinear systems by using two neuro-dynamic structures is ... more ABSTRACT Identification of a class of nonlinear systems by using two neuro-dynamic structures is addressed. The capabilities of the proposed structures for representing the class of system considered are shown analytically. Selection criteria for specifying the fixed structural parameters and adaptation laws for updating the adjustable parameters are provided. Numerical simulation results are also provided to illustrate the performance of the proposed structures
Proceedings of the 1998 IEEE International Conference on Control Applications (Cat. No.98CH36104), 1998
ABSTRACT This paper deals with identification of a multi-input multi-output (MIMO) nonlinear turb... more ABSTRACT This paper deals with identification of a multi-input multi-output (MIMO) nonlinear turbogenerator system by using dynamic neural networks. Using an adaptive time delay neural networks, a neuro-dynamic identifier is proposed. The capability of the proposed structure for representing the nonlinear input-output map of the turbogenerator system is shown analytically. The input-output data set is generated by PSCAD/EMTDC package for a turbogenerator system with default parameters. Simulation results reveal that the proposed neuro-dynamic structure is capable of successfully identifying a highly nonlinear turbogenerator system without any a priori information about the nonlinearities of the system and without any off-line training
Proceedings of 35th IEEE Conference on Decision and Control, 1996
ABSTRACT A simple method for constructing a nonlinear estimator for adaptive friction compensatio... more ABSTRACT A simple method for constructing a nonlinear estimator for adaptive friction compensation is developed. The design is based on Lyapunov technique and attempts to compensate for frictional force by estimating the unknown Coulomb friction coefficient. It is shown that asymptotic stability of the error dynamics is guaranteed without imposing a constraint on the velocity. Simulation results confirm the advantages of the proposed method
2007 International Conference on Intelligent and Advanced Systems, 2007
Arash Mehrafrooz, Alireza Yazdizadeh Dept. of Electrical Engineering, Power and Water University ... more Arash Mehrafrooz, Alireza Yazdizadeh Dept. of Electrical Engineering, Power and Water University of Technology, PO Box 16765-1719, Tehran, Iran arashmehrafrooz@yahoo.com, aryazdizadeh@yahoo.com ... Keywords: Adaptive Control, Smith Rule, Dead-Time Loop, ...
2006 IEEE Conference on Robotics, Automation and Mechatronics, 2006
Abstract Wheeled mobile robots are considered as the most widely used class of mobile robots. Thi... more Abstract Wheeled mobile robots are considered as the most widely used class of mobile robots. This is due to their fast maneuvering, simple controllers, and energy saving characteristics. A new adaptive algorithm for tracking control of these robots is presented in this paper which is robust against external and internal disturbances. A combination of model reference adaptive control and gain scheduling is used to control the robot motion. The simulation results indicate that the designed controller will preserve the robot on its ...
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