Somchai Chatratana - Academia.edu (original) (raw)
Papers by Somchai Chatratana
能源与动力工程 英文版, 2011
The unbalanced voltages cause negative effects on the doubly fed induction generator (DFIG) such ... more The unbalanced voltages cause negative effects on the doubly fed induction generator (DFIG) such as torque pulsation and increased stator current. Based on the symmetrical component theory, the torque pulsation is the consequence of the interaction of stator and rotor currents of different sequences. This paper presents a control technique to reduce the effect of unbalanced voltages on the DFIG in wind energy conversion systems. The negative sequence stator voltage is derived from the unbalanced three phase stator voltages. The compensated rotor voltage in terms of the derived negative sequence stator voltage and slip which minimizes the negative stator and rotor currents is proposed. The results from the simulation of control system with steady state model and dynamic model of the DFIG show that additional control loop with compensated voltage can significantly reduce torque and reactive power pulsations.
Abstract: This paper describes the dynamic behaviour of a doubly-fed induction machine, operating... more Abstract: This paper describes the dynamic behaviour of a doubly-fed induction machine, operating with wind turbine. The rotor circuit of the machine consists only of a generator-side converter working under abnormal condition at stator side (fault condition and voltage drop take place in transmission lines of the grid system). The induction machine model is based on the stationary reference frame and the control-unit model is based on the line-voltage oriented reference frame. The generator-side controller provides good decoupling between active and reactive power. A powerful MATLAB/SIMULINK was used for the simulation of the wind energy conversion system of a 4 kW wind generator. The simulation results of the generator side converter show that the speed, torque and the sinϕ (power factor) can be regulated independently to match the reference signals. The effects of assumed abnormal condition in the grid system are discussed with regard to stator current and rotor current of the in...
This paper explores the Triple Helix development by using the case of the Thai confectionery indu... more This paper explores the Triple Helix development by using the case of the Thai confectionery industry in Thailand which comprises mostly small and very small-sized enterprises. Technology development in small and medium-sized enterprises (SMEs) is considered crucial for innovation and growth of firms. Many government agencies in Thailand have generated support and intervention to promote research and development (R&D) in SMEs. The group approach on the technology development project initiated by the Industrial Technology Assistance Program (ITAP) is one of the most successful cases to significantly improve technology and innovation at the firm level. The group approach which is based on the concept of networking involves various steps of strategic innovation development. Activities in a project with group approach cover survey of industry, seminars and training, preliminary visit, technology acquisition, and business matching. These series of activities create a sustainable innovati...
The business incubator is an important process that admittedly can reduce the risk of failure of ... more The business incubator is an important process that admittedly can reduce the risk of failure of a new entrepreneur. It is also an important process to create a new high growth enterprise. Previously, business incubators in Thailand had been implemented in various departments. However, structural problems exist in such a way that the business incubator is not enough and not in line with business fundamentals and development. The success of a university’s business incubator sponsored by the Commission of Higher Education is that, averagely, in the first two years, there are two new companies and one fully operation company per one business incubator. When taking into account the limitations in various fields, this study proposes different ways to improve the management of the University Business Incubator, through increasing efficiency and preparing a support plan for incubator development on the public university campuses. Policies, strategies and goals of the university in the busi...
International Energy Journal, 2008
The Static Synchronous Series Compensator (SSSC) which is a Series FACT controller, becomes more ... more The Static Synchronous Series Compensator (SSSC) which is a Series FACT controller, becomes more attractive due to its superior abilities over the impedance-based series compensation. These superior abilities can only be achieved by appropriate control schemes and controller settings. This paper investigates two control schemes of the SSSC for the power flow control. In the first scheme, which is called Reactance Emulation Scheme, the SSSC performs a function of the series impedance connected to the transmission line. This performance can be achieved by controlling the quadrature voltage of the SSSC in relation to the transmission line current, and the required series impedance compensation. In t he second control scheme, which is called Quadrature Voltage Control Scheme , the SSSC injects a quadrature voltage into the transmission line. Three modes of compensation, which are capacitive compensation , inductive compensation , and reverse power flow, can be achieved by controlling th...
2009 6th International Conference on Electrical Engineering/Electronics, Computer, Telecommunications and Information Technology, 2009
ldquoManagement of Technology (MOT) is an interdisciplinary field that integrates science, engine... more ldquoManagement of Technology (MOT) is an interdisciplinary field that integrates science, engineering and management knowledge and practice. The focus is on technology as the primary factor in wealth creation. Wealth creation involves more than just money: it may encompass factors such as enhancement of knowledge, intellectual capital, effective exploitation of resources, preservation of the natural environment, and other factors that may contribute to raising the standard of living and quality of life. Managing technology implies managing the systems that enable the creation, acquisition, and exploitation of technology. It involves assuming responsibility for creating, acquiring and spinning out technology to aid human endeavors and satisfy customers' needs. Research, inventions, and development are essential components in technology creation and the enhancement of technology progress. However, more important for the creation of wealth is the exploitation and commercialization of technology. It is when the technology is connected with a customer and that its benefit is realized. A customer is a beneficiary and could be individual, a corporation, or a government entity such as a defense establishment. An invention made and put on a shelf is not contributing to wealth. An idea that emerges and is not exploited, even if it was patented does not bring monetary returns. Technology generates wealth when it is commercialized or used to achieve a desire strategic or operational objective for an organization.rdquo* ......
IEEE Transactions on Industry Applications, 2009
ABSTRACT This paper presents the harmonic study and evaluation when the low-voltage adjustable sp... more ABSTRACT This paper presents the harmonic study and evaluation when the low-voltage adjustable speed drives (ASDs) are applied in an industrial plant The input current characteristics of ASDs are analyzed. The procedure of harmonic study is proposed in step by step fashion. The single-tune filter design with the parameters of the actual network is reviewed and discussed. The evaluation of harmonic distortion for end users according to IEEE Standard 519 is described Finally, the harmonic analysis of an industrial plant is demonstrated by the developed computer program.
This paper describes the dynamic behaviour of a doubly-fed induction machine, operating with wind... more This paper describes the dynamic behaviour of a doubly-fed induction machine, operating with wind turbine. The rotor circuit of the machine consists only of a generator- side converter working under abnormal condition at stator side (fault condition and voltage drop take place in transmission lines of the grid system). The induction machine model is based on the stationary reference frame and the control-unit model is based on the line- voltage oriented reference frame. The generator-side controller provides good decoupling between active and reactive power. A powerful MATLAB/SIMULINK was used for the simulation of the wind energy conversion system of a 4 kW wind generator. The simulation results of the generator side converter show that the speed, torque and the sinϕ (power factor) can be regulated independently to match the reference signals. The effects of assumed abnormal condition in the grid system are discussed with regard to stator current and rotor current of the induction ...
Journal of Electrical Engineering and Technology
... Transm. Distrib., vol. 144, pp. 456-460, Sept. 1997. [7] K. Al-Anbarri, R. Ramanujam, T.Keert... more ... Transm. Distrib., vol. 144, pp. 456-460, Sept. 1997. [7] K. Al-Anbarri, R. Ramanujam, T.Keerthiga and K.Kuppusamy, "Analysis of nonlinear phenomena in MOV connected transformer," IEE Proc.-Gener. Transm. Distrib., vol. 148, pp. 562-566, Nov. 2001. ...
Industry and Higher Education, May 31, 2010
This paper examines the university–industry–government relationship as a mechanism for enhancing ... more This paper examines the university–industry–government relationship as a mechanism for enhancing the efficiency and competitiveness of small and medium-sized enterprises (SMEs). The case of a community enterprise producing dried banana products in the north of Thailand is used to demonstrate the significance of the Triple Helix model for business and technology development in SMEs. Government initiatives designed to promote innovation leading to price and quality competitiveness of the products of SMEs and community enterprises are explored and their effectiveness is discussed. In developing countries, where there are weak links and limited interactions between the institutional sectors of government, academia and industry, intermediaries play a crucial role in building networks to facilitate the transfer and exchange of knowledge. Effective network links would enable SMEs to have access to various sources of financial, knowledge, technology and market support. In Thailand, the Industrial Technology Assistance Programme (ITAP) plays an important intermediary role in identifying the needs of SMEs, accessing relevant knowledge and technology from universities and other sources of knowledge, and matching the demand of SMEs for knowledge/technology with the supply available from universities and research and development laboratories. The experience of the dried banana community enterprise discussed in this paper gives credence to the view that SMEs in developing countries such as Thailand would benefit significantly from technology policy based on the Triple Helix model and the proactive role of intermediary agencies such as ITAP.
Ieej Transactions on Industry Applications, 2008
This paper presents three alternative maxium peak power tracking-based control algorithms with st... more This paper presents three alternative maxium peak power tracking-based control algorithms with stall regulation for optimal wind energy capture: torque reference-based MPPT algorithm, searching-based MPPT algorithm and fuzzy-based MPPT algorithm. The first algorithm uses a torque reference as a guideline for tracking. The second method searches an optimal operating point from the slope of the power-rotational speed curve. The last one achieves the control objective using a developed fuzzy logic rule base. These three algorithms were implemented on a low cost digital signal controller board and tested with a real-time wind turbine simulator. It is found from the experiment that the three algorithms can manage to obtain the maximum power for any input wind speeds but with different control performance in terms of power fluctuation, rotational speed fluctuation and tracking time.
2007 7th International Conference on Power Electronics and Drive Systems, 2007
This paper presents a control technique to reduce the effect of unbalanced voltages in the doubly... more This paper presents a control technique to reduce the effect of unbalanced voltages in the doubly fed induction generator (DFIG) in wind energy conversion systems. The unbalanced voltages cause negative effects to the DFIG such as torque pulsation and increased stator current. Based on the symmetrical component theory, the negative sequence of the stator voltage can be extracted from the
2006 9th International Conference on Control, Automation, Robotics and Vision, 2006
ABSTRACT As the wind has become one of the fastest growing renewable energy sources, the key issu... more ABSTRACT As the wind has become one of the fastest growing renewable energy sources, the key issue of wind energy conversion systems is how to efficiently operate the wind turbines in a wide range of wind speeds. In this paper where small- and medium-sized fixed pitch wind turbines are focused, a control performance analysis of the feedforward and maximum peak power tracking (MPPT) to maximize the power of the turbines while operating in their below rated power and to limit the power while operating in their above rated power is presented. The algorithms were implemented on a low cost digital signal controller (DSC) board and tested with a developed real-time wind turbine simulator, consisting of an induction motor driven by a torque control inverter, and computer interface for data acquisition. The experimental results show that the feedforward performs more satisfactorily when compared to the MPPT and has better performance indices in overall operating conditions. However, the feedforward causes power oscillation in the above rated power and needs wind turbine parameters as a control reference, but those parameters are not necessary in the MPPT, which exhibits an attractive feature
2004 IEEE Region 10 Conference TENCON 2004., 2004
ABSTRACT
2007 International Conference on Electrical Engineering, 2007
This paper analyses the transient stability limit of stator reactive power compensation of doubly... more This paper analyses the transient stability limit of stator reactive power compensation of doubly fed induction machines under the operation of decoupled control of active power and reactive power. Based on the stator-fleld-oriented reference frame, voltage equations are linearized and the corresponding eigenvalues are determined to identify a stable operating region. With the eigenvalues, the maximum reactive power can be
2004 IEEE Region 10 Conference TENCON 2004., 2004
This paper presents the mapping of a hybrid of two most popular control strategies for induction ... more This paper presents the mapping of a hybrid of two most popular control strategies for induction motor drive: field oriented control (FOC) and direct torque control (DTC), with the multilayer feedforward neural network. One neural network is used to map FOC scheme and another network is used to map DTC scheme. The training is made separately with the input-output data obtained from the simulation result of the structural based models. Two trained networks are combined to represent the neural network hybrid control (NNHC). The criterion for switching between the two control schemes is the operating speed of the motor. The simulation results show that this proposed scheme is characterized by fast dynamic performance and good steady state characteristic. Real time implementation of NNHC scheme is discussed.
能源与动力工程 英文版, 2011
The unbalanced voltages cause negative effects on the doubly fed induction generator (DFIG) such ... more The unbalanced voltages cause negative effects on the doubly fed induction generator (DFIG) such as torque pulsation and increased stator current. Based on the symmetrical component theory, the torque pulsation is the consequence of the interaction of stator and rotor currents of different sequences. This paper presents a control technique to reduce the effect of unbalanced voltages on the DFIG in wind energy conversion systems. The negative sequence stator voltage is derived from the unbalanced three phase stator voltages. The compensated rotor voltage in terms of the derived negative sequence stator voltage and slip which minimizes the negative stator and rotor currents is proposed. The results from the simulation of control system with steady state model and dynamic model of the DFIG show that additional control loop with compensated voltage can significantly reduce torque and reactive power pulsations.
Abstract: This paper describes the dynamic behaviour of a doubly-fed induction machine, operating... more Abstract: This paper describes the dynamic behaviour of a doubly-fed induction machine, operating with wind turbine. The rotor circuit of the machine consists only of a generator-side converter working under abnormal condition at stator side (fault condition and voltage drop take place in transmission lines of the grid system). The induction machine model is based on the stationary reference frame and the control-unit model is based on the line-voltage oriented reference frame. The generator-side controller provides good decoupling between active and reactive power. A powerful MATLAB/SIMULINK was used for the simulation of the wind energy conversion system of a 4 kW wind generator. The simulation results of the generator side converter show that the speed, torque and the sinϕ (power factor) can be regulated independently to match the reference signals. The effects of assumed abnormal condition in the grid system are discussed with regard to stator current and rotor current of the in...
This paper explores the Triple Helix development by using the case of the Thai confectionery indu... more This paper explores the Triple Helix development by using the case of the Thai confectionery industry in Thailand which comprises mostly small and very small-sized enterprises. Technology development in small and medium-sized enterprises (SMEs) is considered crucial for innovation and growth of firms. Many government agencies in Thailand have generated support and intervention to promote research and development (R&D) in SMEs. The group approach on the technology development project initiated by the Industrial Technology Assistance Program (ITAP) is one of the most successful cases to significantly improve technology and innovation at the firm level. The group approach which is based on the concept of networking involves various steps of strategic innovation development. Activities in a project with group approach cover survey of industry, seminars and training, preliminary visit, technology acquisition, and business matching. These series of activities create a sustainable innovati...
The business incubator is an important process that admittedly can reduce the risk of failure of ... more The business incubator is an important process that admittedly can reduce the risk of failure of a new entrepreneur. It is also an important process to create a new high growth enterprise. Previously, business incubators in Thailand had been implemented in various departments. However, structural problems exist in such a way that the business incubator is not enough and not in line with business fundamentals and development. The success of a university’s business incubator sponsored by the Commission of Higher Education is that, averagely, in the first two years, there are two new companies and one fully operation company per one business incubator. When taking into account the limitations in various fields, this study proposes different ways to improve the management of the University Business Incubator, through increasing efficiency and preparing a support plan for incubator development on the public university campuses. Policies, strategies and goals of the university in the busi...
International Energy Journal, 2008
The Static Synchronous Series Compensator (SSSC) which is a Series FACT controller, becomes more ... more The Static Synchronous Series Compensator (SSSC) which is a Series FACT controller, becomes more attractive due to its superior abilities over the impedance-based series compensation. These superior abilities can only be achieved by appropriate control schemes and controller settings. This paper investigates two control schemes of the SSSC for the power flow control. In the first scheme, which is called Reactance Emulation Scheme, the SSSC performs a function of the series impedance connected to the transmission line. This performance can be achieved by controlling the quadrature voltage of the SSSC in relation to the transmission line current, and the required series impedance compensation. In t he second control scheme, which is called Quadrature Voltage Control Scheme , the SSSC injects a quadrature voltage into the transmission line. Three modes of compensation, which are capacitive compensation , inductive compensation , and reverse power flow, can be achieved by controlling th...
2009 6th International Conference on Electrical Engineering/Electronics, Computer, Telecommunications and Information Technology, 2009
ldquoManagement of Technology (MOT) is an interdisciplinary field that integrates science, engine... more ldquoManagement of Technology (MOT) is an interdisciplinary field that integrates science, engineering and management knowledge and practice. The focus is on technology as the primary factor in wealth creation. Wealth creation involves more than just money: it may encompass factors such as enhancement of knowledge, intellectual capital, effective exploitation of resources, preservation of the natural environment, and other factors that may contribute to raising the standard of living and quality of life. Managing technology implies managing the systems that enable the creation, acquisition, and exploitation of technology. It involves assuming responsibility for creating, acquiring and spinning out technology to aid human endeavors and satisfy customers' needs. Research, inventions, and development are essential components in technology creation and the enhancement of technology progress. However, more important for the creation of wealth is the exploitation and commercialization of technology. It is when the technology is connected with a customer and that its benefit is realized. A customer is a beneficiary and could be individual, a corporation, or a government entity such as a defense establishment. An invention made and put on a shelf is not contributing to wealth. An idea that emerges and is not exploited, even if it was patented does not bring monetary returns. Technology generates wealth when it is commercialized or used to achieve a desire strategic or operational objective for an organization.rdquo* ......
IEEE Transactions on Industry Applications, 2009
ABSTRACT This paper presents the harmonic study and evaluation when the low-voltage adjustable sp... more ABSTRACT This paper presents the harmonic study and evaluation when the low-voltage adjustable speed drives (ASDs) are applied in an industrial plant The input current characteristics of ASDs are analyzed. The procedure of harmonic study is proposed in step by step fashion. The single-tune filter design with the parameters of the actual network is reviewed and discussed. The evaluation of harmonic distortion for end users according to IEEE Standard 519 is described Finally, the harmonic analysis of an industrial plant is demonstrated by the developed computer program.
This paper describes the dynamic behaviour of a doubly-fed induction machine, operating with wind... more This paper describes the dynamic behaviour of a doubly-fed induction machine, operating with wind turbine. The rotor circuit of the machine consists only of a generator- side converter working under abnormal condition at stator side (fault condition and voltage drop take place in transmission lines of the grid system). The induction machine model is based on the stationary reference frame and the control-unit model is based on the line- voltage oriented reference frame. The generator-side controller provides good decoupling between active and reactive power. A powerful MATLAB/SIMULINK was used for the simulation of the wind energy conversion system of a 4 kW wind generator. The simulation results of the generator side converter show that the speed, torque and the sinϕ (power factor) can be regulated independently to match the reference signals. The effects of assumed abnormal condition in the grid system are discussed with regard to stator current and rotor current of the induction ...
Journal of Electrical Engineering and Technology
... Transm. Distrib., vol. 144, pp. 456-460, Sept. 1997. [7] K. Al-Anbarri, R. Ramanujam, T.Keert... more ... Transm. Distrib., vol. 144, pp. 456-460, Sept. 1997. [7] K. Al-Anbarri, R. Ramanujam, T.Keerthiga and K.Kuppusamy, "Analysis of nonlinear phenomena in MOV connected transformer," IEE Proc.-Gener. Transm. Distrib., vol. 148, pp. 562-566, Nov. 2001. ...
Industry and Higher Education, May 31, 2010
This paper examines the university–industry–government relationship as a mechanism for enhancing ... more This paper examines the university–industry–government relationship as a mechanism for enhancing the efficiency and competitiveness of small and medium-sized enterprises (SMEs). The case of a community enterprise producing dried banana products in the north of Thailand is used to demonstrate the significance of the Triple Helix model for business and technology development in SMEs. Government initiatives designed to promote innovation leading to price and quality competitiveness of the products of SMEs and community enterprises are explored and their effectiveness is discussed. In developing countries, where there are weak links and limited interactions between the institutional sectors of government, academia and industry, intermediaries play a crucial role in building networks to facilitate the transfer and exchange of knowledge. Effective network links would enable SMEs to have access to various sources of financial, knowledge, technology and market support. In Thailand, the Industrial Technology Assistance Programme (ITAP) plays an important intermediary role in identifying the needs of SMEs, accessing relevant knowledge and technology from universities and other sources of knowledge, and matching the demand of SMEs for knowledge/technology with the supply available from universities and research and development laboratories. The experience of the dried banana community enterprise discussed in this paper gives credence to the view that SMEs in developing countries such as Thailand would benefit significantly from technology policy based on the Triple Helix model and the proactive role of intermediary agencies such as ITAP.
Ieej Transactions on Industry Applications, 2008
This paper presents three alternative maxium peak power tracking-based control algorithms with st... more This paper presents three alternative maxium peak power tracking-based control algorithms with stall regulation for optimal wind energy capture: torque reference-based MPPT algorithm, searching-based MPPT algorithm and fuzzy-based MPPT algorithm. The first algorithm uses a torque reference as a guideline for tracking. The second method searches an optimal operating point from the slope of the power-rotational speed curve. The last one achieves the control objective using a developed fuzzy logic rule base. These three algorithms were implemented on a low cost digital signal controller board and tested with a real-time wind turbine simulator. It is found from the experiment that the three algorithms can manage to obtain the maximum power for any input wind speeds but with different control performance in terms of power fluctuation, rotational speed fluctuation and tracking time.
2007 7th International Conference on Power Electronics and Drive Systems, 2007
This paper presents a control technique to reduce the effect of unbalanced voltages in the doubly... more This paper presents a control technique to reduce the effect of unbalanced voltages in the doubly fed induction generator (DFIG) in wind energy conversion systems. The unbalanced voltages cause negative effects to the DFIG such as torque pulsation and increased stator current. Based on the symmetrical component theory, the negative sequence of the stator voltage can be extracted from the
2006 9th International Conference on Control, Automation, Robotics and Vision, 2006
ABSTRACT As the wind has become one of the fastest growing renewable energy sources, the key issu... more ABSTRACT As the wind has become one of the fastest growing renewable energy sources, the key issue of wind energy conversion systems is how to efficiently operate the wind turbines in a wide range of wind speeds. In this paper where small- and medium-sized fixed pitch wind turbines are focused, a control performance analysis of the feedforward and maximum peak power tracking (MPPT) to maximize the power of the turbines while operating in their below rated power and to limit the power while operating in their above rated power is presented. The algorithms were implemented on a low cost digital signal controller (DSC) board and tested with a developed real-time wind turbine simulator, consisting of an induction motor driven by a torque control inverter, and computer interface for data acquisition. The experimental results show that the feedforward performs more satisfactorily when compared to the MPPT and has better performance indices in overall operating conditions. However, the feedforward causes power oscillation in the above rated power and needs wind turbine parameters as a control reference, but those parameters are not necessary in the MPPT, which exhibits an attractive feature
2004 IEEE Region 10 Conference TENCON 2004., 2004
ABSTRACT
2007 International Conference on Electrical Engineering, 2007
This paper analyses the transient stability limit of stator reactive power compensation of doubly... more This paper analyses the transient stability limit of stator reactive power compensation of doubly fed induction machines under the operation of decoupled control of active power and reactive power. Based on the stator-fleld-oriented reference frame, voltage equations are linearized and the corresponding eigenvalues are determined to identify a stable operating region. With the eigenvalues, the maximum reactive power can be
2004 IEEE Region 10 Conference TENCON 2004., 2004
This paper presents the mapping of a hybrid of two most popular control strategies for induction ... more This paper presents the mapping of a hybrid of two most popular control strategies for induction motor drive: field oriented control (FOC) and direct torque control (DTC), with the multilayer feedforward neural network. One neural network is used to map FOC scheme and another network is used to map DTC scheme. The training is made separately with the input-output data obtained from the simulation result of the structural based models. Two trained networks are combined to represent the neural network hybrid control (NNHC). The criterion for switching between the two control schemes is the operating speed of the motor. The simulation results show that this proposed scheme is characterized by fast dynamic performance and good steady state characteristic. Real time implementation of NNHC scheme is discussed.