This paper treats the modeling, and the control of a wind power system based on a doubly fed induction generator DFIG, the stator is directly connected to the grid, while the rotor is powered by multilevel inverters. In order to get a decoupled system of controlfor an independently transits of active and reactive power, a vector control method based on stator flux orientation SFOC is considered: Direct vector control based on PI controllers. Cascaded H-bridge CHBI multilevel inverters are used in the rotor circuit to study its effect on supply power quality. All simulation models are built in MATLAB/Simulink software. Results and waveforms clearly show the effectiveness of vector control strategy. Finally, performances of the system will tested and compared for each levels of inverter.
A Performance Comparison of DFIG using Power Transfer Matrix and Direct Power...IAES-IJPEDS
This paper presents a direct power control and power transfer matrix model for a doubly-fed induction generator (DFIG) wind energy system (WES). Control of DFIG wind turbine system is traditionally based on either stator- flux-oriented or stator-voltage-oriented vector control. The performance of Direct Power Control (DPC) and Power transfer Matrix control for the same wind speed are studied. The Power transfer matrix Control gave better results. The validity and performance of the proposed modelling and control approaches are investigated using a study system consisting of a grid connected DFIG WES. The performance of DFIG with Power Transfer Matrix and Direct Power Control (DPC) techniques are obtained through simulation. The time domain simulation of the study system using MATLAB Simulink is carried out. The results obtained in the two cases are compared.
In recent years, wind energy has become one of the most promising renewable energy sources. Various wind turbine concepts with different generator topologies have been developed to convert this abundant energy into electric power. The doubly-fed induction generator (DFIG) is currently the most common type of generator used in wind farms. Usually the DFIG generator is a wound rotor induction machine, where the stator circuit is directly connected to grid while the rotor’s winding is connected to the grid via a three-phase converter. This paper describes an approach for the independent control of the active and reactive powers of the variable-speed DFIG. The simulation model including a 1.5 MW-DFIG driven by a wind turbine, a PWM back-to-back inverter and the proposed control strategy are developed and implemented using MATLAB/Simulink/SimPowerSystems environment.
Indirect power control of DFIG based on wind turbine operating in MPPT using ...IJECEIAES
This paper describes a MPPT control of the stator powers of a DFIG operating within a wind energy system using the backstepping control technique. The objective of this work consists of providing a robust control to the rotor-side converter allowing the stator active power to be regulated at the maximum power extracted from the wind turbine, as well as maintaining the stator reactive power at zero to maintain the power factor at unity, under various conditions. We have used the Matlab/Simulink platform to model the wind system based on a 7.5 kW DFIG and to implement the MPPT control algorithm in a first step, then we have implemented the field-oriented control and the backstepping controller in a second step. The simulation results obtained were very satisfactory with a fast transient response and neglected power ripples. They furthermore confirmed the high robustness of the approach used in dealing with the variation of the internal parameters of the machine.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
A Performance Comparison of DFIG using Power Transfer Matrix and Direct Power...IAES-IJPEDS
This paper presents a direct power control and power transfer matrix model for a doubly-fed induction generator (DFIG) wind energy system (WES). Control of DFIG wind turbine system is traditionally based on either stator- flux-oriented or stator-voltage-oriented vector control. The performance of Direct Power Control (DPC) and Power transfer Matrix control for the same wind speed are studied. The Power transfer matrix Control gave better results. The validity and performance of the proposed modelling and control approaches are investigated using a study system consisting of a grid connected DFIG WES. The performance of DFIG with Power Transfer Matrix and Direct Power Control (DPC) techniques are obtained through simulation. The time domain simulation of the study system using MATLAB Simulink is carried out. The results obtained in the two cases are compared.
In recent years, wind energy has become one of the most promising renewable energy sources. Various wind turbine concepts with different generator topologies have been developed to convert this abundant energy into electric power. The doubly-fed induction generator (DFIG) is currently the most common type of generator used in wind farms. Usually the DFIG generator is a wound rotor induction machine, where the stator circuit is directly connected to grid while the rotor’s winding is connected to the grid via a three-phase converter. This paper describes an approach for the independent control of the active and reactive powers of the variable-speed DFIG. The simulation model including a 1.5 MW-DFIG driven by a wind turbine, a PWM back-to-back inverter and the proposed control strategy are developed and implemented using MATLAB/Simulink/SimPowerSystems environment.
Indirect power control of DFIG based on wind turbine operating in MPPT using ...IJECEIAES
This paper describes a MPPT control of the stator powers of a DFIG operating within a wind energy system using the backstepping control technique. The objective of this work consists of providing a robust control to the rotor-side converter allowing the stator active power to be regulated at the maximum power extracted from the wind turbine, as well as maintaining the stator reactive power at zero to maintain the power factor at unity, under various conditions. We have used the Matlab/Simulink platform to model the wind system based on a 7.5 kW DFIG and to implement the MPPT control algorithm in a first step, then we have implemented the field-oriented control and the backstepping controller in a second step. The simulation results obtained were very satisfactory with a fast transient response and neglected power ripples. They furthermore confirmed the high robustness of the approach used in dealing with the variation of the internal parameters of the machine.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This paper proposes a feedback linearization control of doubly fed induction generator based wind energy systems for improving decoupled control of the active and reactive powers stator. In order to enhance dynamic performance of the controller studied, the adopted control is reinforced by a fuzzy logic controller. This approach is designed without any model of rotor flux estimation. The difficulty of measuring of rotor flux is overcome by using high gain observer. The stability of the nonlinear observer is proved by the Lyapunov theory. Numerical simulations using MATLAB-SIMULINK shown clearly the robustness of the proposed control, particularly to the disturbance rejection and parametric variations compared with the conventional method.
In this research paper we investigate the modelling and control of a doubly fed induction generator (DFIG) driven in rotation by wind turbine, the control objectives is to optimize capture wind, extract the maximum of the power generated to the grid using MPPT algorithm (Maximum Power Point Tracking) and have a specified reactive power generated whatever wind speed variable, the indirect field oriented control IFOC with the PI correctors was used to achieve such as decoupled control. To validate the dynamique performance of our controller the whole system was simulated using dSPACE DS1104 Controller board Real Time Interface (RTI) which runs in Simulink/MATLAB software and ControlDesk 4.2 graphical interfaces.
Analysis of PMSG in Wind Integration using T Source Inverter with Simple Boos...IJTET Journal
The Analysis of PMSG in wind integration using a T-source Inverter with the Simple Boost Control technique for
improving voltage gain is proposed. The Permanent Magnet Synchronous Generator (PMSG) offers higher performance than other
generators because of its higher efficiency with less maintenance. Since they don’t have rotor current, can be used without a gearbox,
which also implies a reduction of the weight of the nacelle with a reduction of costs. T-Source Inverter has high frequency, low
leakage inductance transformer and one capacitance this is the main difference from the Z-source Inverter. It has low active
components in compare with conventional ZSI. The T source network has an ability to perform DC to AC power conversion. It
provides buck boost operation in a single stage, but the traditional Inverter cannot provide such feature. All the components of the
wind turbine and the grid-side converter are developed and implemented in MATLAB/Simulink.
Wind Energy Conversion System Using PMSG with T-Source Three Phase Matrix Con...IJTET Journal
This paper presents an analysis of a PMSG wind power system using T-Sourcethree phase matrix converter. PMSG using T-Source three phase matrix converterhas advantages that it can provide any desired AC output voltage regardless of DC input with regulation in shoot-through time. In this control system T-Source capacitor voltage can be kept stable with variations in the shoot-through time, maximum power from the wind turbine to be delivered. Inaddition, of a new future, the converter employs a safe-commutation strategy toconduct along a continuous current flow, which results in theelimination of voltage spikes on switches without the need for a snubber circuit. With the use of matrix converter the surely need forrectifier circuit and passive components to store energy arereduced. The MATLAB/Simulinkmodel of the overall system is carried out and theoretical wind energy conversion output load voltage calculations are madeand feasibility of the new topology has been verified and that theconverter can produce an output voltage and output current. This proposed method has greater efficiency and lower cost.
This paper focuses on the modeling and control of a wind energy conversion chain using a permanent magnet synchronous machine. This system behaves a turbine, a generator, DC/DC and DC/AC power converters. These are connected on both sides to the DC bus, where the inverter is followed by a filter which is connected to the grid. In this paper, we have been used two types of controllers. For the stator side converter, we consider the Takagi-Sugeno approach where the parameters of controller have been computed by the theory of linear matrix inequalities. The stability synthesis has been checked using the Lyapunov theory. According to the grid side converter, the proportional integral controller is exploited to keep a constant voltage on the DC bus and control both types of powers. The simulation results demonstrate the robustness of the approach used.
Intelligent Control for Doubly Fed Induction Generator Connected to the Elect...IJPEDS-IAES
In this paper we are interested in optimizing the wind power capture, using the Doubly Fed Induction Generator (DFIG). This machine is preferred to other types of variable speed generator because of their advantages in economic terms and control. The Artificial Neural Network (ANN) based on Direct Torque Control (DTC) which is used to control the electromagnetic torque in order to extract the maximum power. The main objective of this intelligent technique is to replace the conventional switching table by a voltage selector based on (ANN) to reduce torque and flux ripples. Moreover, the fuzzy logic controller is used to grid side converter to keep DC link voltage constant, and also to achieve unity power factor operation. The main advantage of the two control strategies proposed in this paper is that they are not influenced by the variation of the machine parameter. The pitch control is also presented to limit the generator power at its rated value. Simulation results of 1,5 MW, for (DFIG) based Wind Energy Conversion System (WECS) confirm the effectiveness and the performance of the global proposed approaches.
Power Control of Wind Turbine Based on Fuzzy Sliding-Mode ControlIJPEDS-IAES
This paper presents the study of a variable speed wind energy conversion system (WECS) using a Wound Field Synchronous Generator (WFSG) based on a Fuzzy sliding mode control (FSMC) applied to achieve control of active and reactive powers exchanged between the stator of the WFSG and the grid to ensure a Maximum Power Point Tracking (MPPT) of a wind energy conversion system. However the principal drawback of the sliding mode, is the chattering effect which characterized by torque ripple, this phenomena is undesirable and harmful for the machines, it generates noises and additional forces of torsion on the machine shaft. A direct fuzzy logic controller is designed and the sliding mode controller is added to compensate the fuzzy approximation errors. The simulation results clearly indicate the effectiveness and validity of the proposed method, in terms of convergence, time and precision.
Independent Control of Active and Reactive Powers of a DFIG Based Wind Energy...IJERA Editor
The paper deals with a design and implementation of a doubly fed induction generator (DFIG) wind energy conversion system (WECS) connected to the power grid. A back-to-back AC/DC/AC converter is incorporated between the stator and the rotor windings of a DFIG, in order to obtain variable speed operation. The DFIG can be controlled from sub-synchronous speed to super synchronous speed operation. The main objective of the paper is to control the flow of the Active and Reactive powers produced by the DFIG based wind energy conversion system. A vector control strategy with stator flux orientation is applied to both the grid side converter and the rotor side converter for the independent control of Active and reactive powers produced by the DFIG based wind energy conversion system. The system along with its control circuit were simulated in a Matlab/simulink and the results are presented and discussed.
Dynamic responses improvement of grid connected wpgs using flc in high wind s...ijscmcj
Environmental and sustainability concerns are developing the significance of distributed generation (DG) based on renewable energy sources. In this paper, dynamic responses investigation of grid connected wind turbine using permanent magnet synchronous generator (PMSG) under variable wind speeds and load circumstances is carried out. In order to control of turbine output power using Fuzzy Logic controller (FLC) in comparison with PI controller is proposed. Furthermore, the pitch angle based on FLC using wind speed and active power as inputs, can have faster responses, thereby leading to smoother power curves, enhancement of dynamic performance of wind turbine and prevention of mechanical damages to PMSG. Inverter adjusted the DC link voltage and active power is fed by d-axis and reactive power is fed by q-axis (using P-Q control mode). Simulation of wind power generation system (WPGS) is carried out in Matlab/Simulink, and the results verify the correctness and feasibility of control strategy.
The following article presents the control of the power generated by the Doubly Fed Induction Generator, integrated into the wind system, whose rotor is linked to the power converters (Rotor Side Convert (RSC) and Grid Side Converter (GSC)) interfaced by the DC-BUS and connected to the grid via a filter (Rf, Lf) in order to obtain an optimal power to the grid and to ensure system stability. The objective of this study is to understand and to make the comparison between Sliding mode Control technique and the Flux Oriented Control in order to control the Doubly Fed Induction Generator powers exchanged with the grid, it also aims at maintaining the DC-BUS voltage constant and a unit power factor at the grid connection point.The results of simulation show the performance of the Sliding mode Control in terms of monitoring, and robustness with regard to the parametric variations, compared to the Flux Oriented Control. The performance of the systems was tested and compared with the use of MATLAB/Simulink software.
Active and Reactive Power Control of a Doubly Fed Induction GeneratorIJPEDS-IAES
Wind energy has many advantages, it does not pollute and it is an inexhaustible source. However, the cost of this energy is still too high to compete with traditional fossil fuels, especially on sites less windy. The performance of a wind turbine depends on three parameters: the power of wind, the power curve of the turbine and the generator's ability to respond to wind fluctuations. This paper presents a control chain conversion based on a double-fed asynchronous machine (D.F.I.G). To improve the transient and steady state performance and the power factor of generation, a stator flux oriented vector control scheme is used in this work. The vector control structure employs conventional PI controllers for the decoupled control of the stator side active and reactive power. The whole system is modeled and simulated using Matlab/Simulink and the results are analyzed.
Modeling and Control of a Doubly-Fed Induction Generator for Wind Turbine-Gen...IJPEDS-IAES
This paper presents a vector control direct (FOC) of double fed induction generator intended to control the generated stator powers. This device is intended to be implemented in a variable-speed wind-energy conversion system connected to the grid. In order to control the active and reactive power exchanged between the machine stator and the grid, the rotor is fed by a bi-directional converter. The DFIG is controlled by standard relay controllers. Details of the control strategy and system simulation were performed using Simulink and the results are presented in this here to show the effectiveness of the proposed control strategy.
This paper presents the modeling and simulation of wind energy Conversion System using the Permanent Magnet Synchronous Generator (PMSG). The objectives are: to extract the maximum power of the wind speed by controlling the electromagnetic torque of the PMSG, to maintain constant the DC-link voltage despite the wind speed variations and to attain the unity power factor. In order to ensure a regulation with high performance and a good robustness against the internal and the external disturbances, a new control strategy called the Active Disturbance Rejection Control (ADRC) is used. Therefore, the Analysis and simulation of the ADRC and PI controllers are developed with MATLAB/Simulink software. The performance of these controllers is compared in term of references tracking, robustness and grid faults.
Most of generators utilized in wind turbines are the Doubly-Fed Induction Generator (DFIG). Indirect matrix converter (IMC) is a candidate for substituting the traditional back-to-back converter in the future due to advantages gained by elimination of electrolytic capacitor. Starting DFIG wind turbines and synchronizing to the grid is a challenge in practice because of large inrush currents that could damage switches. Synchronizing the DFIG wind turbine controlled by the IMC is presented in this paper. Also, maximum power point tracking algorithm performance of this configuration is examined. A laboratory scale prototype of the proposed configuration is built. Experimental results have confirmed effectiveness of this configuration.
Abstract: Wind energy is becoming the most effective renewable energy source mainly because of the growing concerns over carbon emissions and uncertainties in fossil fuel supplies and the government policy impetus. The increasing penetration of wind power in distribution systems may significantly affect VAR compensation and max. Power tracking of the systems, particularly during wind turbine cut-in and cut-off disturbances.
A DFIG based wind turbine has an ability to generate maximum power with varying and adjustable speed, ability to control active and reactive power by the integration of electronic power converters, low power rating of cost converter components, and so on. This study presents an overview and literature survey over past few decades on the different problems associated due to penetration of WT-DFIG in the power system and control aspects of DFIG.
This paper proposes a feedback linearization control of doubly fed induction generator based wind energy systems for improving decoupled control of the active and reactive powers stator. In order to enhance dynamic performance of the controller studied, the adopted control is reinforced by a fuzzy logic controller. This approach is designed without any model of rotor flux estimation. The difficulty of measuring of rotor flux is overcome by using high gain observer. The stability of the nonlinear observer is proved by the Lyapunov theory. Numerical simulations using MATLAB-SIMULINK shown clearly the robustness of the proposed control, particularly to the disturbance rejection and parametric variations compared with the conventional method.
In this research paper we investigate the modelling and control of a doubly fed induction generator (DFIG) driven in rotation by wind turbine, the control objectives is to optimize capture wind, extract the maximum of the power generated to the grid using MPPT algorithm (Maximum Power Point Tracking) and have a specified reactive power generated whatever wind speed variable, the indirect field oriented control IFOC with the PI correctors was used to achieve such as decoupled control. To validate the dynamique performance of our controller the whole system was simulated using dSPACE DS1104 Controller board Real Time Interface (RTI) which runs in Simulink/MATLAB software and ControlDesk 4.2 graphical interfaces.
Analysis of PMSG in Wind Integration using T Source Inverter with Simple Boos...IJTET Journal
The Analysis of PMSG in wind integration using a T-source Inverter with the Simple Boost Control technique for
improving voltage gain is proposed. The Permanent Magnet Synchronous Generator (PMSG) offers higher performance than other
generators because of its higher efficiency with less maintenance. Since they don’t have rotor current, can be used without a gearbox,
which also implies a reduction of the weight of the nacelle with a reduction of costs. T-Source Inverter has high frequency, low
leakage inductance transformer and one capacitance this is the main difference from the Z-source Inverter. It has low active
components in compare with conventional ZSI. The T source network has an ability to perform DC to AC power conversion. It
provides buck boost operation in a single stage, but the traditional Inverter cannot provide such feature. All the components of the
wind turbine and the grid-side converter are developed and implemented in MATLAB/Simulink.
Wind Energy Conversion System Using PMSG with T-Source Three Phase Matrix Con...IJTET Journal
This paper presents an analysis of a PMSG wind power system using T-Sourcethree phase matrix converter. PMSG using T-Source three phase matrix converterhas advantages that it can provide any desired AC output voltage regardless of DC input with regulation in shoot-through time. In this control system T-Source capacitor voltage can be kept stable with variations in the shoot-through time, maximum power from the wind turbine to be delivered. Inaddition, of a new future, the converter employs a safe-commutation strategy toconduct along a continuous current flow, which results in theelimination of voltage spikes on switches without the need for a snubber circuit. With the use of matrix converter the surely need forrectifier circuit and passive components to store energy arereduced. The MATLAB/Simulinkmodel of the overall system is carried out and theoretical wind energy conversion output load voltage calculations are madeand feasibility of the new topology has been verified and that theconverter can produce an output voltage and output current. This proposed method has greater efficiency and lower cost.
This paper focuses on the modeling and control of a wind energy conversion chain using a permanent magnet synchronous machine. This system behaves a turbine, a generator, DC/DC and DC/AC power converters. These are connected on both sides to the DC bus, where the inverter is followed by a filter which is connected to the grid. In this paper, we have been used two types of controllers. For the stator side converter, we consider the Takagi-Sugeno approach where the parameters of controller have been computed by the theory of linear matrix inequalities. The stability synthesis has been checked using the Lyapunov theory. According to the grid side converter, the proportional integral controller is exploited to keep a constant voltage on the DC bus and control both types of powers. The simulation results demonstrate the robustness of the approach used.
Intelligent Control for Doubly Fed Induction Generator Connected to the Elect...IJPEDS-IAES
In this paper we are interested in optimizing the wind power capture, using the Doubly Fed Induction Generator (DFIG). This machine is preferred to other types of variable speed generator because of their advantages in economic terms and control. The Artificial Neural Network (ANN) based on Direct Torque Control (DTC) which is used to control the electromagnetic torque in order to extract the maximum power. The main objective of this intelligent technique is to replace the conventional switching table by a voltage selector based on (ANN) to reduce torque and flux ripples. Moreover, the fuzzy logic controller is used to grid side converter to keep DC link voltage constant, and also to achieve unity power factor operation. The main advantage of the two control strategies proposed in this paper is that they are not influenced by the variation of the machine parameter. The pitch control is also presented to limit the generator power at its rated value. Simulation results of 1,5 MW, for (DFIG) based Wind Energy Conversion System (WECS) confirm the effectiveness and the performance of the global proposed approaches.
Power Control of Wind Turbine Based on Fuzzy Sliding-Mode ControlIJPEDS-IAES
This paper presents the study of a variable speed wind energy conversion system (WECS) using a Wound Field Synchronous Generator (WFSG) based on a Fuzzy sliding mode control (FSMC) applied to achieve control of active and reactive powers exchanged between the stator of the WFSG and the grid to ensure a Maximum Power Point Tracking (MPPT) of a wind energy conversion system. However the principal drawback of the sliding mode, is the chattering effect which characterized by torque ripple, this phenomena is undesirable and harmful for the machines, it generates noises and additional forces of torsion on the machine shaft. A direct fuzzy logic controller is designed and the sliding mode controller is added to compensate the fuzzy approximation errors. The simulation results clearly indicate the effectiveness and validity of the proposed method, in terms of convergence, time and precision.
Independent Control of Active and Reactive Powers of a DFIG Based Wind Energy...IJERA Editor
The paper deals with a design and implementation of a doubly fed induction generator (DFIG) wind energy conversion system (WECS) connected to the power grid. A back-to-back AC/DC/AC converter is incorporated between the stator and the rotor windings of a DFIG, in order to obtain variable speed operation. The DFIG can be controlled from sub-synchronous speed to super synchronous speed operation. The main objective of the paper is to control the flow of the Active and Reactive powers produced by the DFIG based wind energy conversion system. A vector control strategy with stator flux orientation is applied to both the grid side converter and the rotor side converter for the independent control of Active and reactive powers produced by the DFIG based wind energy conversion system. The system along with its control circuit were simulated in a Matlab/simulink and the results are presented and discussed.
Dynamic responses improvement of grid connected wpgs using flc in high wind s...ijscmcj
Environmental and sustainability concerns are developing the significance of distributed generation (DG) based on renewable energy sources. In this paper, dynamic responses investigation of grid connected wind turbine using permanent magnet synchronous generator (PMSG) under variable wind speeds and load circumstances is carried out. In order to control of turbine output power using Fuzzy Logic controller (FLC) in comparison with PI controller is proposed. Furthermore, the pitch angle based on FLC using wind speed and active power as inputs, can have faster responses, thereby leading to smoother power curves, enhancement of dynamic performance of wind turbine and prevention of mechanical damages to PMSG. Inverter adjusted the DC link voltage and active power is fed by d-axis and reactive power is fed by q-axis (using P-Q control mode). Simulation of wind power generation system (WPGS) is carried out in Matlab/Simulink, and the results verify the correctness and feasibility of control strategy.
The following article presents the control of the power generated by the Doubly Fed Induction Generator, integrated into the wind system, whose rotor is linked to the power converters (Rotor Side Convert (RSC) and Grid Side Converter (GSC)) interfaced by the DC-BUS and connected to the grid via a filter (Rf, Lf) in order to obtain an optimal power to the grid and to ensure system stability. The objective of this study is to understand and to make the comparison between Sliding mode Control technique and the Flux Oriented Control in order to control the Doubly Fed Induction Generator powers exchanged with the grid, it also aims at maintaining the DC-BUS voltage constant and a unit power factor at the grid connection point.The results of simulation show the performance of the Sliding mode Control in terms of monitoring, and robustness with regard to the parametric variations, compared to the Flux Oriented Control. The performance of the systems was tested and compared with the use of MATLAB/Simulink software.
Active and Reactive Power Control of a Doubly Fed Induction GeneratorIJPEDS-IAES
Wind energy has many advantages, it does not pollute and it is an inexhaustible source. However, the cost of this energy is still too high to compete with traditional fossil fuels, especially on sites less windy. The performance of a wind turbine depends on three parameters: the power of wind, the power curve of the turbine and the generator's ability to respond to wind fluctuations. This paper presents a control chain conversion based on a double-fed asynchronous machine (D.F.I.G). To improve the transient and steady state performance and the power factor of generation, a stator flux oriented vector control scheme is used in this work. The vector control structure employs conventional PI controllers for the decoupled control of the stator side active and reactive power. The whole system is modeled and simulated using Matlab/Simulink and the results are analyzed.
Modeling and Control of a Doubly-Fed Induction Generator for Wind Turbine-Gen...IJPEDS-IAES
This paper presents a vector control direct (FOC) of double fed induction generator intended to control the generated stator powers. This device is intended to be implemented in a variable-speed wind-energy conversion system connected to the grid. In order to control the active and reactive power exchanged between the machine stator and the grid, the rotor is fed by a bi-directional converter. The DFIG is controlled by standard relay controllers. Details of the control strategy and system simulation were performed using Simulink and the results are presented in this here to show the effectiveness of the proposed control strategy.
This paper presents the modeling and simulation of wind energy Conversion System using the Permanent Magnet Synchronous Generator (PMSG). The objectives are: to extract the maximum power of the wind speed by controlling the electromagnetic torque of the PMSG, to maintain constant the DC-link voltage despite the wind speed variations and to attain the unity power factor. In order to ensure a regulation with high performance and a good robustness against the internal and the external disturbances, a new control strategy called the Active Disturbance Rejection Control (ADRC) is used. Therefore, the Analysis and simulation of the ADRC and PI controllers are developed with MATLAB/Simulink software. The performance of these controllers is compared in term of references tracking, robustness and grid faults.
Most of generators utilized in wind turbines are the Doubly-Fed Induction Generator (DFIG). Indirect matrix converter (IMC) is a candidate for substituting the traditional back-to-back converter in the future due to advantages gained by elimination of electrolytic capacitor. Starting DFIG wind turbines and synchronizing to the grid is a challenge in practice because of large inrush currents that could damage switches. Synchronizing the DFIG wind turbine controlled by the IMC is presented in this paper. Also, maximum power point tracking algorithm performance of this configuration is examined. A laboratory scale prototype of the proposed configuration is built. Experimental results have confirmed effectiveness of this configuration.
Abstract: Wind energy is becoming the most effective renewable energy source mainly because of the growing concerns over carbon emissions and uncertainties in fossil fuel supplies and the government policy impetus. The increasing penetration of wind power in distribution systems may significantly affect VAR compensation and max. Power tracking of the systems, particularly during wind turbine cut-in and cut-off disturbances.
A DFIG based wind turbine has an ability to generate maximum power with varying and adjustable speed, ability to control active and reactive power by the integration of electronic power converters, low power rating of cost converter components, and so on. This study presents an overview and literature survey over past few decades on the different problems associated due to penetration of WT-DFIG in the power system and control aspects of DFIG.
Abstract: Wind energy is becoming the most effective renewable energy source mainly because of the growing concerns over carbon emissions and uncertainties in fossil fuel supplies and the government policy impetus. The increasing penetration of wind power in distribution systems may significantly affect VAR compensation and max. Power tracking of the systems, particularly during wind turbine cut-in and cut-off disturbances.
A DFIG based wind turbine has an ability to generate maximum power with varying and adjustable speed, ability to control active and reactive power by the integration of electronic power converters, low power rating of cost converter components, and so on. This study presents an overview and literature survey over past few decades on the different problems associated due to penetration of WT-DFIG in the power system and control aspects of DFIG.
Wind energy has many advantages, it does not pollute and it is an inexhaustible source. However, the cost of this energy is still too high to compete with traditional fossil sources. The yield of a wind turbine depends on three parameters: the power of the wind, the turbine power curve and the ability of the generator to respond to fluctuations in the wind. This article presented the MPPT of a wind turbine system equipped with an asynchronous generator has dual power under MatlabSimulink program, in the first time we simulated all the conversion chain with complete model of DFIG and vector control in second stepthen applied the extracted maximum power MPPT strategists, this command is effective and has several advantages it offered to kept the maximum power delivered to network despite all the parameter is change.
Improved Control Strategy for Low Voltage Ride Through Capability of DFIG wit...ecij
This paper deals with a protection and control strategy to enhance the low voltage ride through capability of a wind turbine driven doubly fed induction generator (DFIG). As the wind power penetration continues to increase, wind turbines are required to provide Low Voltage Ride-Through (LVRT) capability. Crowbars are commonly used to protect the power converters during voltage dips and their main drawback is that the DFIG absorbs reactive power from the grid during grid faults. According to emergency grid code requirements, wind farms should have the ability to stay connected and continue generation under external voltage failure conditions, that is, wind turbines have to keep in connection with grid and own continue reactive power supply. This paper proposes a hysteresis current control strategy for the crowbar protection
and a reactive power control to satisfy the grid code requirements. Consequently, the dynamic model of double fed wind turbines is established to study the transient behavior of DFIG. Simulation results are presented to show the effectiveness of the proposed control scheme.
This article addresses the problem of controlling an overall wind energy conversion system (WECS) formed by a wind turbine connected to the grid via a doubly fed introduction generator (DFIG) and an AC/DC/AC converter. The main control objectives are fourfold: (i) designing an output feedback speed controller that makes the DFIG rotate at the optimal value delivered by the MPPT strategy, (ii) controlling the stator reactive power so as to be null, (iii) guaranteeing the DC-link voltage in the grid side converter to be at a given constant value, (iv) ensuring a unitary power factor. A high gain observer is synthesized, in order to provide estimated values of the mechanical variables. To achieve the control objectives, a sliding mode controller involving the mechanical observer is designed. The performance of the system configuration based on the 2MW-DFIG with the proposed controller is evaluated by a numerical simulation under a realistic wind profile using MATLAB/SIMULINK/SimPowerSystems environment.
Indirect Control of a Doubly-Fed Induction Machine for Wind Energy ConversionIAES-IJPEDS
In this paper, a grid connected wind power generation scheme using a doubly fed induction generator (DFIG) is studied. The aims of this paper are: The modelling and simulation of the operating in two quadrants (torque-speed) of a DFIG, the analysis employs a stator flux vector control algorithm to control rotor current, the system enables optimal speed tracking for maximum energy capture from the wind and high performance active and reactive power regulation using the PI regulator. The simulation calculations were achieved ®®
using MATLAB -SIMULINK package. Lastly, the obtained results are presented, for different operating points, illustrating the good control performances of the system
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DYNAMIC RESPONSES IMPROVEMENT OF GRID CONNECTED WPGS USING FLC IN HIGH WIND S...ijscmcjournal
Environmental and sustainability concerns are developing the significance of distributed generation (DG) based on renewable energy sources. In this paper, dynamic responses investigation of grid connected wind turbine using permanent magnet synchronous generator (PMSG) under variable wind speeds and load circumstances is carried out. In order to control of turbine output power using Fuzzy Logic controller (FLC) in comparison with PI controller is proposed. Furthermore, the pitch angle based on FLC using wind speed and active power as inputs, can have faster responses, thereby leading to smoother power curves, enhancement of dynamic performance of wind turbine and prevention of mechanical damages to PMSG. Inverter adjusted the DC link voltage and active power is fed by d-axis and reactive power is fed by q-axis (using P-Q control mode). Simulation of wind power generation system (WPGS) is carried out in Matlab/Simulink, and the results verify the correctness and feasibility of control strategy.
The paper proposes a complete modeling and control technique of variable speed wind turbine system (WTS) based on the doubly fed induction generator (DFIG). Two levels back-to-back converter is used to ensure the energy transfer between the DFIG rotor and the grid. The wind turbine to operate efficiently, a maximum power point tracking (MPPT) algorithm is implemented. Then, direct power control (DPC) strategy has been combined with the MPPT technique in order to guarantee the selection of the appropriate rotor voltage vectors and to minimize the active and reactive power errors. Finally, the simulation is performed by using MATLAB/simulink platform basing on 7.5KW DFIG wind generation system, and the results prove the effectiveness of our proposed control technique.
ENHANCED CONTROL OF DFIG IN WIND ENERGY CONVERSION SYSTEMIjorat1
The doubly-fed induction generator (DFIG) wind turbine is a variable speed wind turbine widely used
in the modern wind power industries. At present, commercial DFIG wind turbines primarily make use of the
technology that was developed a decade ago. But, it is found in the paper that there is limitations conventional
control method. This project presents a fuzzy-logic approach to control the DFIG. Based on which fuzzy-logic
approach is controlled for real power, reactive power flow and electromagnetic torque of the wind turbine. A
direct current vector control strategy is developed to control the rotor side voltage source converter. This scheme
of direct current vector control strategy allows the independent control of the generated active and reactive
power as well as the rotor speed. In this project, a fuzzy-logic approach is proposed to control the DFIG. The
active and reactive power is controlled by rotor voltage, which goes through back-to-back voltage source
converter and DC-link voltage is also maintained stable. The conventional control approach is compared with the
proposed control techniques for DFIG wind turbine control under both steady and gusty wind conditions. A
MATLAB based simulation system was build to validate the effectiveness of the proposed method. The proposed
method waveforms of real power, reactive power, DC link voltage and generator speed are compared with
conventional method. This paper shows that under the fuzzy-logic approach control techniques, a DFIG system
have a superior performance in various aspects.
Optimized servo-speed control of wind turbine coupled to doubly fed inductio...IJECEIAES
Optimal control of any variable speed wind turbine needs maximum power point tracking (MPPT) coupled to doubly fed induction generator (DFIG) for better power generation. This paper offers a novel direct power servo-speed control of wind turbine. This latter is based on DFIG optimal hysteresis MPPT inverter current control combined with space voltage modulation (SVM) inverter voltage technique, thus providing a stable and continuous energy flow to power grid. In this design, the asynchronous machine stator is directly connected to the grid. Bidirectional power converter, acting as frequency converter, is rotor circuit located. Rectifier supplies rotor windings with voltages and reference frequency resulting from control procedure of the power exchange between the stator and grid. Inverter is directly controlled by means of SVM technique to maintain direct current (DC) bus voltage constant. Simulation results show that the proposed configuration improves power converters efficiency due that rotor circuit needs less power than stator circuit which is injected into the grid.
Integration of a Wind Turbine Based Doubly Fed Induction Generator Using STAT...IJERA Editor
Wind power stations mostly placed in remote areas; so they are characterized by weak grids and are often submitted to power system disturbance like faults, voltage sag etc. In this paper the crowbar protection method is used to ride through voltage sags and STATCOM is used to quickly sense the voltage sag and overcome it. The behavior of these machines during grid failure is an important issue. DFIG consists of a common induction generator with slip ring and a partial scale power electronic converter. Indirect field oriented controller is applied to rotor side converter for active power control and voltage regulation of wind turbine. On grid side PQ control scheme is applied. Wind turbine and its control units are described in details and also for STATCOM control. All power system components are simulated in MATLAB/ SIMULINK software. For studying the performance of controller, different abnormal conditions are applied even the worst case. Simulation results prove that the performance of STATCOM and DFIG control schemes as improving power quality and stability of wind turbine.
Enhanced Crowbar Protection for Fault Ride through Capability of Wind Generat...IAES-IJPEDS
Due to increasing demand in power, the integration of renewable sources like
wind generation into power system is gaining much importance nowadays.
The heavy penetration of wind power into the power system leads to many
integration issues mainly due to the intermittent nature of the wind and the
desirability for variable speed operation of the generators. As the wind power
generation depends on the wind speed, its integration into the grid has
noticeable influence on the system stability and becomes an important issue
especially when a fault occurs on the grid. The protective disconnection of a
large amount of wind power during a fault will be an unacceptable
consequence and threatens the power system stability. With the increasing
use of wind turbines employing Doubly Fed Induction Generator (DFIG)
technology, it becomes a necessity to investigate their behavior during grid
faults and support them with fault ride through capability. This paper
presents the modeling and simulation of a doubly fed induction generator
according to grid code compatibility driven by a wind turbine connected to
the grid. This paper analyses the voltage sag due to a three-phase fault in the
wind connected grid. A control strategy including a crowbar circuit has been
developed in MATLAB/SIMULINK to bypass the rotor over currents during
grid fault to enhance the fault ride through capability and to maintain system
stability. Simulation results show the effectiveness of the proposed control
strategies in DFIG based grid connected wind turbine system.
A Fuzzy Logic Control Strategy for Doubly Fed Induction Generator for Improve...IAES-IJPEDS
In this paper, which is t

decouple PI control for output active and reactive powers
he common control technique for power converter of Doubly Fed
Induction Generator (DFIG) is presented. But there are some disadvantages with this control method like uncertainty about the exact model, behavior of some parameters or unpredictable wind speed and tuning of PI parameters. To overcome the mentioned disadvantages a fuzzy logic control of DFIG wind turbine is presented and is compared with PI controller. To validate the proposed scheme, simulation results are presented, these results showed that the performance of fuzzy control of DFIG is excellent and it improves power quality and stability of wind turbine compared to PI controller. The Fuzzy logic controller is applied to rotor side converter for active power control and voltage regulation of wind turbine. The entire work is carried out in MATLab/Simulink. Different faulty operating conditions are considered to
prove the effective implementation of the proposed control scheme.
Real time simulation of nonlinear generalized predictive control for wind ene...ISA Interchange
In order to make a wind power generation truly cost-effective and reliable, an advanced control techniques must be used. In this paper, we develop a new control strategy, using nonlinear generalized predictive control (NGPC) approach, for DFIG-based wind turbine. The proposed control law is based on two points: NGPC-based torque-current control loop generating the rotor reference voltage and NGPC-based speed control loop that provides the torque reference. In order to enhance the robustness of the controller, a disturbance observer is designed to estimate the aerodynamic torque which is considered as an unknown perturbation. Finally, a real-time simulation is carried out to illustrate the performance of the proposed controller.
Load Frequency Control of DFIG-isolated and Grid Connected ModeIJAPEJOURNAL
Wind energy is one of the extraordinary promising sources of renewable energy due to its clean character, free availability and economic viability. A Doubly Fed Induction Generator (DFIG) feeds power from both the stator and the rotor windings at speeds above synchronous speed of the machine. This paper deals the load frequency control of doubly fed induction generator in isolated mode and grid connected mode. The wind turbine model is obtained using MATLAB/ SIMULINK which consists of DFIG, rotor side rectifier, grid side inverter and grid. This model is controlled by conventional controllerand proposed Load Frequency Control (LFC) method. The results are proven that frequency control gives better results in all the aspects
Bibliometric analysis highlighting the role of women in addressing climate ch...IJECEIAES
Fossil fuel consumption increased quickly, contributing to climate change
that is evident in unusual flooding and draughts, and global warming. Over
the past ten years, women's involvement in society has grown dramatically,
and they succeeded in playing a noticeable role in reducing climate change.
A bibliometric analysis of data from the last ten years has been carried out to
examine the role of women in addressing the climate change. The analysis's
findings discussed the relevant to the sustainable development goals (SDGs),
particularly SDG 7 and SDG 13. The results considered contributions made
by women in the various sectors while taking geographic dispersion into
account. The bibliometric analysis delves into topics including women's
leadership in environmental groups, their involvement in policymaking, their
contributions to sustainable development projects, and the influence of
gender diversity on attempts to mitigate climate change. This study's results
highlight how women have influenced policies and actions related to climate
change, point out areas of research deficiency and recommendations on how
to increase role of the women in addressing the climate change and
achieving sustainability. To achieve more successful results, this initiative
aims to highlight the significance of gender equality and encourage
inclusivity in climate change decision-making processes.
Voltage and frequency control of microgrid in presence of micro-turbine inter...IJECEIAES
The active and reactive load changes have a significant impact on voltage
and frequency. In this paper, in order to stabilize the microgrid (MG) against
load variations in islanding mode, the active and reactive power of all
distributed generators (DGs), including energy storage (battery), diesel
generator, and micro-turbine, are controlled. The micro-turbine generator is
connected to MG through a three-phase to three-phase matrix converter, and
the droop control method is applied for controlling the voltage and
frequency of MG. In addition, a method is introduced for voltage and
frequency control of micro-turbines in the transition state from gridconnected mode to islanding mode. A novel switching strategy of the matrix
converter is used for converting the high-frequency output voltage of the
micro-turbine to the grid-side frequency of the utility system. Moreover,
using the switching strategy, the low-order harmonics in the output current
and voltage are not produced, and consequently, the size of the output filter
would be reduced. In fact, the suggested control strategy is load-independent
and has no frequency conversion restrictions. The proposed approach for
voltage and frequency regulation demonstrates exceptional performance and
favorable response across various load alteration scenarios. The suggested
strategy is examined in several scenarios in the MG test systems, and the
simulation results are addressed.
Enhancing battery system identification: nonlinear autoregressive modeling fo...IJECEIAES
Precisely characterizing Li-ion batteries is essential for optimizing their
performance, enhancing safety, and prolonging their lifespan across various
applications, such as electric vehicles and renewable energy systems. This
article introduces an innovative nonlinear methodology for system
identification of a Li-ion battery, employing a nonlinear autoregressive with
exogenous inputs (NARX) model. The proposed approach integrates the
benefits of nonlinear modeling with the adaptability of the NARX structure,
facilitating a more comprehensive representation of the intricate
electrochemical processes within the battery. Experimental data collected
from a Li-ion battery operating under diverse scenarios are employed to
validate the effectiveness of the proposed methodology. The identified
NARX model exhibits superior accuracy in predicting the battery's behavior
compared to traditional linear models. This study underscores the
importance of accounting for nonlinearities in battery modeling, providing
insights into the intricate relationships between state-of-charge, voltage, and
current under dynamic conditions.
Smart grid deployment: from a bibliometric analysis to a surveyIJECEIAES
Smart grids are one of the last decades' innovations in electrical energy.
They bring relevant advantages compared to the traditional grid and
significant interest from the research community. Assessing the field's
evolution is essential to propose guidelines for facing new and future smart
grid challenges. In addition, knowing the main technologies involved in the
deployment of smart grids (SGs) is important to highlight possible
shortcomings that can be mitigated by developing new tools. This paper
contributes to the research trends mentioned above by focusing on two
objectives. First, a bibliometric analysis is presented to give an overview of
the current research level about smart grid deployment. Second, a survey of
the main technological approaches used for smart grid implementation and
their contributions are highlighted. To that effect, we searched the Web of
Science (WoS), and the Scopus databases. We obtained 5,663 documents
from WoS and 7,215 from Scopus on smart grid implementation or
deployment. With the extraction limitation in the Scopus database, 5,872 of
the 7,215 documents were extracted using a multi-step process. These two
datasets have been analyzed using a bibliometric tool called bibliometrix.
The main outputs are presented with some recommendations for future
research.
Use of analytical hierarchy process for selecting and prioritizing islanding ...IJECEIAES
One of the problems that are associated to power systems is islanding
condition, which must be rapidly and properly detected to prevent any
negative consequences on the system's protection, stability, and security.
This paper offers a thorough overview of several islanding detection
strategies, which are divided into two categories: classic approaches,
including local and remote approaches, and modern techniques, including
techniques based on signal processing and computational intelligence.
Additionally, each approach is compared and assessed based on several
factors, including implementation costs, non-detected zones, declining
power quality, and response times using the analytical hierarchy process
(AHP). The multi-criteria decision-making analysis shows that the overall
weight of passive methods (24.7%), active methods (7.8%), hybrid methods
(5.6%), remote methods (14.5%), signal processing-based methods (26.6%),
and computational intelligent-based methods (20.8%) based on the
comparison of all criteria together. Thus, it can be seen from the total weight
that hybrid approaches are the least suitable to be chosen, while signal
processing-based methods are the most appropriate islanding detection
method to be selected and implemented in power system with respect to the
aforementioned factors. Using Expert Choice software, the proposed
hierarchy model is studied and examined.
Enhancing of single-stage grid-connected photovoltaic system using fuzzy logi...IJECEIAES
The power generated by photovoltaic (PV) systems is influenced by
environmental factors. This variability hampers the control and utilization of
solar cells' peak output. In this study, a single-stage grid-connected PV
system is designed to enhance power quality. Our approach employs fuzzy
logic in the direct power control (DPC) of a three-phase voltage source
inverter (VSI), enabling seamless integration of the PV connected to the
grid. Additionally, a fuzzy logic-based maximum power point tracking
(MPPT) controller is adopted, which outperforms traditional methods like
incremental conductance (INC) in enhancing solar cell efficiency and
minimizing the response time. Moreover, the inverter's real-time active and
reactive power is directly managed to achieve a unity power factor (UPF).
The system's performance is assessed through MATLAB/Simulink
implementation, showing marked improvement over conventional methods,
particularly in steady-state and varying weather conditions. For solar
irradiances of 500 and 1,000 W/m2
, the results show that the proposed
method reduces the total harmonic distortion (THD) of the injected current
to the grid by approximately 46% and 38% compared to conventional
methods, respectively. Furthermore, we compare the simulation results with
IEEE standards to evaluate the system's grid compatibility.
Enhancing photovoltaic system maximum power point tracking with fuzzy logic-b...IJECEIAES
Photovoltaic systems have emerged as a promising energy resource that
caters to the future needs of society, owing to their renewable, inexhaustible,
and cost-free nature. The power output of these systems relies on solar cell
radiation and temperature. In order to mitigate the dependence on
atmospheric conditions and enhance power tracking, a conventional
approach has been improved by integrating various methods. To optimize
the generation of electricity from solar systems, the maximum power point
tracking (MPPT) technique is employed. To overcome limitations such as
steady-state voltage oscillations and improve transient response, two
traditional MPPT methods, namely fuzzy logic controller (FLC) and perturb
and observe (P&O), have been modified. This research paper aims to
simulate and validate the step size of the proposed modified P&O and FLC
techniques within the MPPT algorithm using MATLAB/Simulink for
efficient power tracking in photovoltaic systems.
Adaptive synchronous sliding control for a robot manipulator based on neural ...IJECEIAES
Robot manipulators have become important equipment in production lines, medical fields, and transportation. Improving the quality of trajectory tracking for
robot hands is always an attractive topic in the research community. This is a
challenging problem because robot manipulators are complex nonlinear systems
and are often subject to fluctuations in loads and external disturbances. This
article proposes an adaptive synchronous sliding control scheme to improve trajectory tracking performance for a robot manipulator. The proposed controller
ensures that the positions of the joints track the desired trajectory, synchronize
the errors, and significantly reduces chattering. First, the synchronous tracking
errors and synchronous sliding surfaces are presented. Second, the synchronous
tracking error dynamics are determined. Third, a robust adaptive control law is
designed,the unknown components of the model are estimated online by the neural network, and the parameters of the switching elements are selected by fuzzy
logic. The built algorithm ensures that the tracking and approximation errors
are ultimately uniformly bounded (UUB). Finally, the effectiveness of the constructed algorithm is demonstrated through simulation and experimental results.
Simulation and experimental results show that the proposed controller is effective with small synchronous tracking errors, and the chattering phenomenon is
significantly reduced.
Remote field-programmable gate array laboratory for signal acquisition and de...IJECEIAES
A remote laboratory utilizing field-programmable gate array (FPGA) technologies enhances students’ learning experience anywhere and anytime in embedded system design. Existing remote laboratories prioritize hardware access and visual feedback for observing board behavior after programming, neglecting comprehensive debugging tools to resolve errors that require internal signal acquisition. This paper proposes a novel remote embeddedsystem design approach targeting FPGA technologies that are fully interactive via a web-based platform. Our solution provides FPGA board access and debugging capabilities beyond the visual feedback provided by existing remote laboratories. We implemented a lab module that allows users to seamlessly incorporate into their FPGA design. The module minimizes hardware resource utilization while enabling the acquisition of a large number of data samples from the signal during the experiments by adaptively compressing the signal prior to data transmission. The results demonstrate an average compression ratio of 2.90 across three benchmark signals, indicating efficient signal acquisition and effective debugging and analysis. This method allows users to acquire more data samples than conventional methods. The proposed lab allows students to remotely test and debug their designs, bridging the gap between theory and practice in embedded system design.
Detecting and resolving feature envy through automated machine learning and m...IJECEIAES
Efficiently identifying and resolving code smells enhances software project quality. This paper presents a novel solution, utilizing automated machine learning (AutoML) techniques, to detect code smells and apply move method refactoring. By evaluating code metrics before and after refactoring, we assessed its impact on coupling, complexity, and cohesion. Key contributions of this research include a unique dataset for code smell classification and the development of models using AutoGluon for optimal performance. Furthermore, the study identifies the top 20 influential features in classifying feature envy, a well-known code smell, stemming from excessive reliance on external classes. We also explored how move method refactoring addresses feature envy, revealing reduced coupling and complexity, and improved cohesion, ultimately enhancing code quality. In summary, this research offers an empirical, data-driven approach, integrating AutoML and move method refactoring to optimize software project quality. Insights gained shed light on the benefits of refactoring on code quality and the significance of specific features in detecting feature envy. Future research can expand to explore additional refactoring techniques and a broader range of code metrics, advancing software engineering practices and standards.
Smart monitoring technique for solar cell systems using internet of things ba...IJECEIAES
Rapidly and remotely monitoring and receiving the solar cell systems status parameters, solar irradiance, temperature, and humidity, are critical issues in enhancement their efficiency. Hence, in the present article an improved smart prototype of internet of things (IoT) technique based on embedded system through NodeMCU ESP8266 (ESP-12E) was carried out experimentally. Three different regions at Egypt; Luxor, Cairo, and El-Beheira cities were chosen to study their solar irradiance profile, temperature, and humidity by the proposed IoT system. The monitoring data of solar irradiance, temperature, and humidity were live visualized directly by Ubidots through hypertext transfer protocol (HTTP) protocol. The measured solar power radiation in Luxor, Cairo, and El-Beheira ranged between 216-1000, 245-958, and 187-692 W/m 2 respectively during the solar day. The accuracy and rapidity of obtaining monitoring results using the proposed IoT system made it a strong candidate for application in monitoring solar cell systems. On the other hand, the obtained solar power radiation results of the three considered regions strongly candidate Luxor and Cairo as suitable places to build up a solar cells system station rather than El-Beheira.
An efficient security framework for intrusion detection and prevention in int...IJECEIAES
Over the past few years, the internet of things (IoT) has advanced to connect billions of smart devices to improve quality of life. However, anomalies or malicious intrusions pose several security loopholes, leading to performance degradation and threat to data security in IoT operations. Thereby, IoT security systems must keep an eye on and restrict unwanted events from occurring in the IoT network. Recently, various technical solutions based on machine learning (ML) models have been derived towards identifying and restricting unwanted events in IoT. However, most ML-based approaches are prone to miss-classification due to inappropriate feature selection. Additionally, most ML approaches applied to intrusion detection and prevention consider supervised learning, which requires a large amount of labeled data to be trained. Consequently, such complex datasets are impossible to source in a large network like IoT. To address this problem, this proposed study introduces an efficient learning mechanism to strengthen the IoT security aspects. The proposed algorithm incorporates supervised and unsupervised approaches to improve the learning models for intrusion detection and mitigation. Compared with the related works, the experimental outcome shows that the model performs well in a benchmark dataset. It accomplishes an improved detection accuracy of approximately 99.21%.
Developing a smart system for infant incubators using the internet of things ...IJECEIAES
This research is developing an incubator system that integrates the internet of things and artificial intelligence to improve care for premature babies. The system workflow starts with sensors that collect data from the incubator. Then, the data is sent in real-time to the internet of things (IoT) broker eclipse mosquito using the message queue telemetry transport (MQTT) protocol version 5.0. After that, the data is stored in a database for analysis using the long short-term memory network (LSTM) method and displayed in a web application using an application programming interface (API) service. Furthermore, the experimental results produce as many as 2,880 rows of data stored in the database. The correlation coefficient between the target attribute and other attributes ranges from 0.23 to 0.48. Next, several experiments were conducted to evaluate the model-predicted value on the test data. The best results are obtained using a two-layer LSTM configuration model, each with 60 neurons and a lookback setting 6. This model produces an R 2 value of 0.934, with a root mean square error (RMSE) value of 0.015 and a mean absolute error (MAE) of 0.008. In addition, the R 2 value was also evaluated for each attribute used as input, with a result of values between 0.590 and 0.845.
A review on internet of things-based stingless bee's honey production with im...IJECEIAES
Honey is produced exclusively by honeybees and stingless bees which both are well adapted to tropical and subtropical regions such as Malaysia. Stingless bees are known for producing small amounts of honey and are known for having a unique flavor profile. Problem identified that many stingless bees collapsed due to weather, temperature and environment. It is critical to understand the relationship between the production of stingless bee honey and environmental conditions to improve honey production. Thus, this paper presents a review on stingless bee's honey production and prediction modeling. About 54 previous research has been analyzed and compared in identifying the research gaps. A framework on modeling the prediction of stingless bee honey is derived. The result presents the comparison and analysis on the internet of things (IoT) monitoring systems, honey production estimation, convolution neural networks (CNNs), and automatic identification methods on bee species. It is identified based on image detection method the top best three efficiency presents CNN is at 98.67%, densely connected convolutional networks with YOLO v3 is 97.7%, and DenseNet201 convolutional networks 99.81%. This study is significant to assist the researcher in developing a model for predicting stingless honey produced by bee's output, which is important for a stable economy and food security.
A trust based secure access control using authentication mechanism for intero...IJECEIAES
The internet of things (IoT) is a revolutionary innovation in many aspects of our society including interactions, financial activity, and global security such as the military and battlefield internet. Due to the limited energy and processing capacity of network devices, security, energy consumption, compatibility, and device heterogeneity are the long-term IoT problems. As a result, energy and security are critical for data transmission across edge and IoT networks. Existing IoT interoperability techniques need more computation time, have unreliable authentication mechanisms that break easily, lose data easily, and have low confidentiality. In this paper, a key agreement protocol-based authentication mechanism for IoT devices is offered as a solution to this issue. This system makes use of information exchange, which must be secured to prevent access by unauthorized users. Using a compact contiki/cooja simulator, the performance and design of the suggested framework are validated. The simulation findings are evaluated based on detection of malicious nodes after 60 minutes of simulation. The suggested trust method, which is based on privacy access control, reduced packet loss ratio to 0.32%, consumed 0.39% power, and had the greatest average residual energy of 0.99 mJoules at 10 nodes.
Fuzzy linear programming with the intuitionistic polygonal fuzzy numbersIJECEIAES
In real world applications, data are subject to ambiguity due to several factors; fuzzy sets and fuzzy numbers propose a great tool to model such ambiguity. In case of hesitation, the complement of a membership value in fuzzy numbers can be different from the non-membership value, in which case we can model using intuitionistic fuzzy numbers as they provide flexibility by defining both a membership and a non-membership functions. In this article, we consider the intuitionistic fuzzy linear programming problem with intuitionistic polygonal fuzzy numbers, which is a generalization of the previous polygonal fuzzy numbers found in the literature. We present a modification of the simplex method that can be used to solve any general intuitionistic fuzzy linear programming problem after approximating the problem by an intuitionistic polygonal fuzzy number with n edges. This method is given in a simple tableau formulation, and then applied on numerical examples for clarity.
The performance of artificial intelligence in prostate magnetic resonance im...IJECEIAES
Prostate cancer is the predominant form of cancer observed in men worldwide. The application of magnetic resonance imaging (MRI) as a guidance tool for conducting biopsies has been established as a reliable and well-established approach in the diagnosis of prostate cancer. The diagnostic performance of MRI-guided prostate cancer diagnosis exhibits significant heterogeneity due to the intricate and multi-step nature of the diagnostic pathway. The development of artificial intelligence (AI) models, specifically through the utilization of machine learning techniques such as deep learning, is assuming an increasingly significant role in the field of radiology. In the realm of prostate MRI, a considerable body of literature has been dedicated to the development of various AI algorithms. These algorithms have been specifically designed for tasks such as prostate segmentation, lesion identification, and classification. The overarching objective of these endeavors is to enhance diagnostic performance and foster greater agreement among different observers within MRI scans for the prostate. This review article aims to provide a concise overview of the application of AI in the field of radiology, with a specific focus on its utilization in prostate MRI.
Seizure stage detection of epileptic seizure using convolutional neural networksIJECEIAES
According to the World Health Organization (WHO), seventy million individuals worldwide suffer from epilepsy, a neurological disorder. While electroencephalography (EEG) is crucial for diagnosing epilepsy and monitoring the brain activity of epilepsy patients, it requires a specialist to examine all EEG recordings to find epileptic behavior. This procedure needs an experienced doctor, and a precise epilepsy diagnosis is crucial for appropriate treatment. To identify epileptic seizures, this study employed a convolutional neural network (CNN) based on raw scalp EEG signals to discriminate between preictal, ictal, postictal, and interictal segments. The possibility of these characteristics is explored by examining how well timedomain signals work in the detection of epileptic signals using intracranial Freiburg Hospital (FH), scalp Children's Hospital Boston-Massachusetts Institute of Technology (CHB-MIT) databases, and Temple University Hospital (TUH) EEG. To test the viability of this approach, two types of experiments were carried out. Firstly, binary class classification (preictal, ictal, postictal each versus interictal) and four-class classification (interictal versus preictal versus ictal versus postictal). The average accuracy for stage detection using CHB-MIT database was 84.4%, while the Freiburg database's time-domain signals had an accuracy of 79.7% and the highest accuracy of 94.02% for classification in the TUH EEG database when comparing interictal stage to preictal stage.
Analysis of driving style using self-organizing maps to analyze driver behaviorIJECEIAES
Modern life is strongly associated with the use of cars, but the increase in acceleration speeds and their maneuverability leads to a dangerous driving style for some drivers. In these conditions, the development of a method that allows you to track the behavior of the driver is relevant. The article provides an overview of existing methods and models for assessing the functioning of motor vehicles and driver behavior. Based on this, a combined algorithm for recognizing driving style is proposed. To do this, a set of input data was formed, including 20 descriptive features: About the environment, the driver's behavior and the characteristics of the functioning of the car, collected using OBD II. The generated data set is sent to the Kohonen network, where clustering is performed according to driving style and degree of danger. Getting the driving characteristics into a particular cluster allows you to switch to the private indicators of an individual driver and considering individual driving characteristics. The application of the method allows you to identify potentially dangerous driving styles that can prevent accidents.
Hyperspectral object classification using hybrid spectral-spatial fusion and ...IJECEIAES
Because of its spectral-spatial and temporal resolution of greater areas, hyperspectral imaging (HSI) has found widespread application in the field of object classification. The HSI is typically used to accurately determine an object's physical characteristics as well as to locate related objects with appropriate spectral fingerprints. As a result, the HSI has been extensively applied to object identification in several fields, including surveillance, agricultural monitoring, environmental research, and precision agriculture. However, because of their enormous size, objects require a lot of time to classify; for this reason, both spectral and spatial feature fusion have been completed. The existing classification strategy leads to increased misclassification, and the feature fusion method is unable to preserve semantic object inherent features; This study addresses the research difficulties by introducing a hybrid spectral-spatial fusion (HSSF) technique to minimize feature size while maintaining object intrinsic qualities; Lastly, a soft-margins kernel is proposed for multi-layer deep support vector machine (MLDSVM) to reduce misclassification. The standard Indian pines dataset is used for the experiment, and the outcome demonstrates that the HSSF-MLDSVM model performs substantially better in terms of accuracy and Kappa coefficient.
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
Presented at NUS: Fuzzing and Software Security Summer School 2024
This keynote talks about the democratization of fuzzing at scale, highlighting the collaboration between open source communities, academia, and industry to advance the field of fuzzing. It delves into the history of fuzzing, the development of scalable fuzzing platforms, and the empowerment of community-driven research. The talk will further discuss recent advancements leveraging AI/ML and offer insights into the future evolution of the fuzzing landscape.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
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Student information management system project report ii.pdfKamal Acharya
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TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
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COLLEGE BUS MANAGEMENT SYSTEM PROJECT REPORT.pdfKamal Acharya
The College Bus Management system is completely developed by Visual Basic .NET Version. The application is connect with most secured database language MS SQL Server. The application is develop by using best combination of front-end and back-end languages. The application is totally design like flat user interface. This flat user interface is more attractive user interface in 2017. The application is gives more important to the system functionality. The application is to manage the student’s details, driver’s details, bus details, bus route details, bus fees details and more. The application has only one unit for admin. The admin can manage the entire application. The admin can login into the application by using username and password of the admin. The application is develop for big and small colleges. It is more user friendly for non-computer person. Even they can easily learn how to manage the application within hours. The application is more secure by the admin. The system will give an effective output for the VB.Net and SQL Server given as input to the system. The compiled java program given as input to the system, after scanning the program will generate different reports. The application generates the report for users. The admin can view and download the report of the data. The application deliver the excel format reports. Because, excel formatted reports is very easy to understand the income and expense of the college bus. This application is mainly develop for windows operating system users. In 2017, 73% of people enterprises are using windows operating system. So the application will easily install for all the windows operating system users. The application-developed size is very low. The application consumes very low space in disk. Therefore, the user can allocate very minimum local disk space for this application.
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Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
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power extraction. In variable-speed operation, a control method designed to extract maximum power from
the wind turbine and provide constant grid voltage and frequency is required [4].
In this paper, a variable-speed wind turbine is considered with DFIG and a multilevel cascaded
H-Bridge Inverter CHBI. Multilevel inverters are AC-DC-AC converters, well suited for medium and
high-power applications [5] due to their ability to meet the increasing demand of power ratings and power
quality associated with reduced harmonic distortion, lower electromagnetic interference, and higher
efficiencies when compared with the conventional two or three level topology [6]. The increasing number of
voltage levels lead to the production of high-power quality waveforms [7], causing the total harmonic
distortion THD to be lower. Multilevel converters are a good tradeoff solution between performance and cost
in wind high-power systems [8].
The most typical connection diagram of this DFIG is to connect stator directly to the grid, while the rotor
is supplied through a controlled power converter. This solution is more attractive for all applications where speed
variations are limited around the synchronous speed because this area operating presents low slip, and therefore
the converter associated with the rotor has to be treated only for a fraction of 20 to 30 % of the nominal
conversion system power; this means that the losses in the converter are reduced (power supplied to the rotor
is low) and the cost thereof is reduced. That is why we find this machine in high power variable speed and
constant frequency for production systems. A second reason is the possibility of controlling the active and
reactive power in the stator via the control of the power converter [9].
Further variable speed wind turbine is modeled to find a relationship between the electromagnetic
torque and the mechanical wind speed. After describing mechanical and electrical model of the DFIG in
section 3, a vector control method based on stator flux orientation SFOC is considered: direct vector control
based on PI controllers. The sinus pulse wave modulation (SPWM) control strategyfor multilevel invertersis
given in section 4. Finally, simulation and results are presented; performances of the system are then evaluated.
2. WIND TURBINE MODEL
Mechanical power available on the shaft of a wind turbine is expressed by [10]:
𝑃𝑣 =
1
2
𝜌𝑆𝑣𝑣
3
=
1
2
𝜌𝜋𝑅2
𝑣𝑣
3 (1)
where:
ρ :air density (1.25 Kg/m3
);
R : Blade length in meters;
Vv : wind velocity in m/s.
The aerodynamic power extracted from wind turbine canbe calculated as:
𝑃𝑇𝑢𝑟𝑏 = 𝐶 𝑝 𝑃𝑣 =
1
2
𝜌𝑆𝑣𝑣
3
=
1
2
𝜌𝜋𝑅2
𝑣𝑣
3
. 𝐶 𝑝(𝜆, 𝛽) (2)
𝜆 =
Ω 𝑇𝑢𝑟𝑏. 𝑅
𝑣𝑣
(3)
where:
Cp : Power coefficient;
β : Pitch angle (deg);
λ :Tip speed ratio;
ΩTurb : Turbine speed (rd/s).
No wind turbine could convert more than 59 % of the kinetic energy of the wind into mechanical
energy turning a rotor [11]. This is known as the Betz limit, and it is the theoretical maximum coefficient of
power for any wind turbine: Cpmax= 16/27 ≈ 0.593. The multiplier is mathematically modeled by
the following equations:
{
𝑇 𝑚 =
𝑇𝑇𝑢𝑟𝑏
𝐺
Ω 𝑇𝑢𝑟𝑏 =
Ω 𝑚
𝐺
𝐽 𝑇 =
𝐽 𝑇𝑢𝑟𝑏
𝐺2 + 𝐽 𝑔
𝑇𝑇𝑢𝑟𝑏 =
𝑃 𝑇𝑢𝑟𝑏
Ω 𝑇𝑢𝑟𝑏
(4)
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where:
Ωturb, Ωm: Turbine speed respectively before and afterthe multiplier;Tturb: aerodynamic torque; Tm: torque after
the multiplier; G: Gear ratio; Jg: Generator inertia; JT: Total inertia; JTurb: Turbine inertia.
The fundamental equation of dynamics to determine the evolution of the mechanical speed from
the total mechanical torque 𝑇 𝑚𝑒𝑐 applied to the rotor:
𝐽 𝑇
𝑑Ω 𝑚𝑒𝑐
𝑑𝑡
= 𝑇 𝑚𝑒𝑐 = 𝑇 𝑚 − 𝑇𝑒𝑚 − 𝐶𝑓Ω 𝑚𝑒𝑐 (5)
where:
Tem : Electromagnetic torque; Cf: Viscous friction coefficient.
2.1. Modeling of the DFIG, Park’s model
The d-q axis representation of DFIG is used for modeling, considering flux as variable based on
Park's model. All rotor quantities are referred to stator side. The DFIG model represented by voltage (6).
The stator and rotor side flux linkage equations are given as [12-14]:
{
𝑉𝑠𝑑 = 𝑅𝑠 𝐼𝑠𝑑 +
𝑑Ф 𝑠𝑑
𝑑𝑡
− 𝜔𝑠Ф 𝑠𝑞
𝑉𝑠𝑞 = 𝑅𝑠 𝐼𝑠𝑞 +
𝑑Ф 𝑠𝑞
𝑑𝑡
+ 𝜔𝑠Ф 𝑠𝑑
𝑉𝑟𝑑 = 𝑅 𝑟 𝐼𝑟𝑑 +
𝑑Ф 𝑟𝑑
𝑑𝑡
− (𝜔𝑠 − 𝜔𝑟)Ф 𝑟𝑞
𝑉𝑟𝑞 = 𝑅 𝑟 𝐼𝑟𝑞 +
𝑑Ф 𝑟𝑞
𝑑𝑡
+ (𝜔𝑠 − 𝜔𝑟)Ф 𝑟𝑑
(6)
The stator and rotor flux can be expressed as:
{
Ф 𝑠𝑑 = 𝐿 𝑠 𝐼𝑠𝑑 + 𝐿 𝑚 𝐼𝑟𝑑
Ф 𝑠𝑞 = 𝐿 𝑠 𝐼𝑠𝑞 + 𝐿 𝑚 𝐼𝑟𝑞
Ф 𝑟𝑑 = 𝐿 𝑟 𝐼𝑟𝑑 + 𝐿 𝑚 𝐼𝑠𝑑
Ф 𝑟𝑞 = 𝐿 𝑟 𝐼𝑟𝑞 + 𝐿 𝑚 𝐼𝑠𝑞
(7)
Electromagnetic torque is also expressed in terms of currents and flux:
𝐶𝑒𝑚 = 𝑝
𝐿 𝑚
𝐿 𝑠
(Ф 𝑠𝑑 𝐼𝑞𝑟 − Ф 𝑠𝑞 𝐼 𝑑𝑟) (8)
where:
Rs, Rr, are respectively the stator and rotor resistances; Ls, Lr: inductances of the stator and rotor windings;
Lmis the mutual inductance; Vds, Vqs, Vdret Vqr: Direct and quadrate components of the space phasors of
the stator and rotor voltages; Ids, Iqs, Idr, Iqr: Direct and quadrate components of the space phasors of
the stator and rotor currents; φds, φqs, φdret φqr: Direct and quadrate components of the space phasors of
the stator and rotor flux respectively;
ɷs: Rotational speed of the synchronous reference frame;
ɷr: Rotor speed,
p: Number of pair poles.
Active and reactive powers at the stator (Ps, Qs), and the rotor (Pr, Qr) are defined as [15-16]:
{
𝑃𝑠 = 𝑉𝑠𝑑 𝐼𝑠𝑑 + 𝑉𝑠𝑞 𝐼𝑠𝑞
𝑄𝑠 = 𝑉𝑠𝑞 𝐼𝑠𝑑 − 𝑉𝑠𝑑 𝐼𝑠𝑞
𝑃𝑟 = 𝑉𝑑𝑟 𝐼 𝑑𝑟 + 𝑉𝑞𝑟 𝐼𝑞𝑟
𝑄 𝑟 = 𝑉𝑞𝑟 𝐼 𝑑𝑟 − 𝑉𝑑𝑟 𝐼𝑞𝑟
(9)
2.2. Control strategy of the DFIG
Once the DFIG is connected to an existing grid, the transit of active and reactive powers must be
controlled separately. To obtain a decoupled powers control of DFIG, the method based on field orientation
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can be regarded as the efficient one. The principle of this method consists to orientate the stator flux in such
a way that the stator flux vector points into d-axis direction; this approach is realized by setting the quadratic
component of the stator flux to the null value, detailed representation is show in Figure 1 [17, 18].
Figure 1. Stator flux orientation
The stator fluxes of (6) will be simplified as follows:
{
Ф 𝑠𝑑 = 𝐿 𝑠 𝐼𝑠𝑑 + 𝐿 𝑚 𝐼𝑟𝑑 = Ф 𝑠
Ф 𝑠𝑞 = 𝐿 𝑠 𝐼𝑠𝑞 + 𝐿 𝑚 𝐼𝑟𝑞 = 0
(10)
The stator resistance will be neglected, for medium power machines used in WECS; the stator
voltage vector is consequently in quadrate advance in comparison with the stator flux vector.
{
𝑉𝑠𝑑 = 0
𝑉𝑠𝑞 = 𝜔𝑠Ф 𝑠 = 𝑉𝑠
(11)
Using (10), we can establish the connection between the rotor and stator currents:
{
𝐼𝑠𝑑 = −
𝐿 𝑚
𝐿 𝑠
𝐼𝑟𝑑 +
∅ 𝑠
𝐿 𝑠
𝐼𝑠𝑞 = −
𝐿 𝑚
𝐿 𝑠
𝐼𝑟𝑞
(12)
Using (11) and (12), the stator active and reactive power and rotor voltage are given by:
{
𝑃𝑠 = 𝑉𝑠 𝐼𝑠𝑞 = −𝑉𝑠
𝐿 𝑚
𝐿 𝑠
𝐼𝑟𝑞
𝑄𝑠 = 𝑉𝑠 𝐼𝑠𝑑 = −𝑉𝑠
𝐿 𝑚
𝐿 𝑠
𝐼𝑟𝑑 +
𝑉𝑠
2
𝐿 𝑠 𝑤𝑠
(13)
For controlling the DFIG, established expressions showing the relationship between current and
rotor voltages will be applied to it.
{
𝑉𝑟𝑑 = 𝑅 𝑟 𝐼𝑟𝑑 + (𝐿 𝑟 −
𝐿 𝑚
2
𝐿 𝑠
)
𝑑𝐼𝑟𝑑
𝑑𝑡
− 𝑔𝑤𝑠 (𝐿 𝑟 −
𝐿 𝑚
2
𝐿 𝑠
) 𝐼𝑟𝑞
𝑉𝑟𝑞 = 𝑅 𝑟 𝐼𝑟𝑞 + (𝐿 𝑟 −
𝐿 𝑚
2
𝐿 𝑠
)
𝑑𝐼𝑟𝑞
𝑑𝑡
+ 𝑔𝑤𝑠 (𝐿 𝑟 −
𝐿 𝑚
2
𝐿 𝑠
) 𝐼𝑟𝑑 + 𝑔
𝐿 𝑚 𝑉𝑠
𝐿 𝑠
(14)
By considering σ as the cross coupling term, (14) can be rewrite as:
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{
𝑉𝑟𝑑 = 𝑅 𝑟 𝐼𝑟𝑑 + 𝐿 𝑟 𝜎
𝑑𝐼𝑟𝑑
𝑑𝑡
− 𝑔𝜎𝑤 𝜎 𝐿 𝑟 𝐼𝑟𝑞
𝑉𝑟𝑞 = 𝑅 𝑟 𝐼𝑟𝑞 + 𝐿 𝑟 𝜎
𝑑𝐼𝑟𝑞
𝑑𝑡
+ 𝑔𝜎𝑤𝑠 𝐿 𝑟 𝐼𝑟𝑑 + 𝑔
𝐿 𝑚 𝑉𝑠
𝐿 𝑠
𝜎 = 1 −
𝐿 𝑚
2
𝐿 𝑟 𝐿 𝑠
(15)
The block diagram representing the internal model of the system is shown in Figure 2. Field oriented
control of the DFIG can then be applied with the active and reactive power considered as variables
to be controlled. The input blocks relating 𝑉𝑟𝑑 to 𝑉𝑟𝑞 represent the simplified rotor converter model.
Knowing (13) and (15), it is then possible to synthesize the regulators [19].
Figure 2. Block diagram of the system to regulate
In order to improve the last command, we will introduce an additional control loop at the currents to
eliminate the static error while preserving the dynamics of the system, then, two additional PI controllers are
added to regulate the active and reactive powers. So, we need sixcurrents sensors, three to control the rotor
currents (iar, ibr and icr) and three associated with three voltage sensors to measure the stator powers Ps and Qs.
The active power PI controller regulates the rotor current reference iqr from the error between the active
power measured Ps and the desired active power Pref. Furthermore, the reactive power PI controller regulates
the rotor current reference idr from the error between the reactive power measured Qs and the desired reactive
power Qref. The closed loop control of active and reactive powers is presented in Figure 3:
Figure 3. Closed loop control of active and reactive powers
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3. CASCADED H-BRIDGE INVERTER CHBI THEORY
Several multilevel topologies used for grid connection have been proposed in [20, 21]. Multilevel
converter structures have three major classifications; neutral point clamped (NPCor diode clamped), flying
capacitor (FC or capacitor clamped), and cascaded H-bridge inverter CHBI, with isolated DC source Figure 4.
Compared with the latter two, the multilevel CHBI has many distinct advantages:
Switch devices required are less under the same switching frequency and level number.
The harmonic content is lower in the output voltage for a given switching frequency.
Modularized circuit layout and packaging is possible because each cell has the same structure, and there
are no extra clamping diodes as in the case of diode clamped topology, or voltage balancing capacitors as
in the case of the capacitor clamped topology [22].
.
Vdc
S1
S2
S3
S4
Vout
+
-
Figure 4. Single phase H-bridge inverter
3.1. Theory of cascaded H-Bridge multilevel inverter
The cascaded H bridge multilevel inverter circuit consists of individual H-bridge cells which are fed
by individual dc supply. Each H-bridge cell contains four switches. In this topology, IGBT is used as switch
because of its low switching losses. Each H-bridge generates three different output voltages, +Vdc, 0 and –Vdc
using various combinations of switching with the four switches [22, 23]. The switching tableof the three level
CHB is given in Table 1.
Table 1. Switching table for 3-level CHB inverter
S1 S2 S3 S4 Output Voltage
1 0 0 1 Vdc
0 1 1 0 -Vdc
0 0 0 0 0
Cascaded multilevel inverter is the cascade connection of N H-bridge inverters. Each H-bridge
inverter has the same configuration as a typical single-phase full-bridge inverter. In this topology the number
of phase voltage levels at the converter terminals is 2N+1, where N is the number ofcells or dc link voltages.
The IGBT switches have low block voltage and high switching frequency. Consider the seven level inverter;
it requires 12 IGBT switches and three dc sources. The power circuit ofinverter is shown in Figure 5.
By closing the appropriate switches, each H-bridge inverter can produce three different voltages: +Vdc, 0 and -Vdc.
It is also possible to modularize circuit layout and packaging because each level has the same structure, and
there are no extra clamping diodes or voltage balancing capacitors. The number of switches is reduced using
the newtopology [24, 25].
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S1
S2
S3 S4
Vdc
+
-
S1
S2
S3 S4
Vdc
+
-
S1
S2
S3 S4
Vdc
+
-
S1
S2
S3 S4
Vdc
+
-
S1
S2
S3 S4
Vdc
+
-
S1
S2
S3 S4
Vdc
+
-
S1
S2
S3 S4
Vdc
+
-
S1
S2
S3 S4
Vdc
+
-
S1
S2
S3 S4
Vdc
+
-
Vc
Vb
Va
Vc
N
Figure 5. Cascaded H-bridge 7-level inverter
4. SIMULATION RESULTS
The system based on a variable speed wind turbine with a doubly fed induction generator DFIG.
The simulation is carried out using the MatLab/Simulink software. The DFIG is connected directly to
the network through the stator, and controlled by its rotor through a three level CHBI. Simulation results are
presented in Figure 6 to Figure 14. They show performances of our system.
Figure 6. Wind speed Figure 7. Electromagnetic torque
Figure 8. Isd current Figure 9. Isq current
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Figure 10. Ird current Figure 11. Irq current
Figure 12. Active power Figure 13. Reactive power
Figure 14. Stator currents
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To control the power exchanged between the stator and the network, one uses the vector control
with direct stator flux shown in Figure 15. Simulation results are obtained under various stator active and
reactive power steps. The both control strategies with 5 levels CHBI, and 13 levels CHBI separately,
are simulated, tested and compared in terms of power reference tracking. We initial simulation at first, with
an active power step Psref= -5KW. At time t = 0.5s to 2s an application of the echelon of active power
Psref = - 10KW, and after time t = 2s to 3s we return at step Psref = -5KW. The reactive power step is
changed from Qsref = -1 to -4 KVAR at the instant t = 1 s and again from -4 to -1 KVAR at the instant
t = 1.5 s; a last variation of the reactive power step at the instant t = 2.5 is applied from Qsref =.-1 KVAR.
Simulation results are shown in Figure 16 to Figure 19.
It can be seen that multilevel CHBI can control the active and reactive powers of DFIG with a very
fast time response. However, the ripples in powers are more significant from control with 5 levels CHBI.
To observe the effectiveness of the proposed control strategy, we increased levels of CHBI gradually up to
13 levels. In order to produce quality energy, it is apparent that the control with 13 levels CHBI,
harmonics are almost eliminated. Thus, we estimate that these powers injected into the network will have no
significant impact.
Figure 15. Block diagram of DFIG power control Si tu peux le changer sous forme de bloc c’est mieux
ZOOM
Figure 16. Reel and reference active power with 5 levels CHBI
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ZOOM
Figure 17. Reel and reference reactive power with 5 levels CHBI
ZOOM
Figure 18. Reel and reference active power with 13 levels CHBI
ZOOM
Figure 19. Reel and reference reactive power with 13 levels CHBI
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5. CONCLUSION
The aim of this work is to model and control the doubly fed induction generator DFIG based wind
energy conversion system powered by multitier inverters with cascaded H-Bridge structure, to increase
the power transferred to the network. In this context, a control of the powers of the wind system was carried out.
For adjusting the energy quality supplied by the DFIG, vector control by orientation of the stator flow that
makes the system similar to that of the DC machine was applied. To be able to directly control the active and
reactive DFIG power through multi-level inverters; our strategy was to apply vector control, with
a configuration of H. BRIDGE inverters; and then increase their levels, in order to improve the quality of
the energy delivered by the DFIG; we thus determined the most efficient system for the different
configurations proposed.The global model of our system is at first established. Furthermore, a vector control
strategy of the DFIG to perform power reference tracking to machine parameters variation. The structure
using the DFIG has a best advantage in terms of high power output, in variable speed operation, while
reducing the size of the static converters. Despite this, the use of multilevel converters seems necessary
especially for high power wind turbines. These converters increase the power transmitted to the power grid
by reducing the current ripple and the harmonic content of the output voltages. This increase is done by
means of the voltage, which makes it possible to reduce the losses of power in the lines.The results show that,
using multilevels CHBI, the quality of produced energy is improved, in fact the harmonics that decrease
the efficiency of the system are extremely diminished.
REFERENCES
[1] A. Dendouga, “Contrôle des puissances active et réactive de la machine asynchrone à double alimentation,”
Thèse de doctorat, Université de Batna, 2010.
[2] Patrick Piro, "Guide des énergies vertes pour la maison," Livre éditions : Terre vivante, L'écologie pratique, 2006.
[3] “Evolution et tendances de la demande mondiale en énergie,” [Online]. Available:
http://web.archive.org/web/20080509052730/www.lenergiecreative.com/ (section “énergie et planète”).
[4] Baroudi, J. A, Dinavahi, V and Knight, A. M, “A review of power converter topologies forwind generators,” Renew
Energy, vol. 32, no. 14, pp. 2369-2385, 2007
[5] Lai, J. S and Peng F. Z., “Multilevel converters. A new breed of power converters,” IEEE Transactions on industry
applications, vol. 32, no. 3, pp. 509-517, 1996
[6] Abbes, M, Belhadj, J and Bennani, A. B. A, “Design and control of a direct drive wind turbine equipped with
multilevel converters,” Renew Energy, vol. 35, no. 5, pp. 936-945, 2010.
[7] Babaei. E, Hosseini. S. H, Gharehpetian. G. B, Haque. M. T and Sabahi. M., “Reduction of dc voltage sources and
switches in asymmetrical multilevel converters using a novel topology,” Electric Power Systems Research, vol. 77,
no. 8, pp. 1073-85, 2007.
[8] R. Melício a, V. M. F. Mendes. B and J. P. S. Catalão, “Power converter topologies for wind energy conversion
systems: Integrated modeling, control strategy and performance simulation,” Renewable Energy, vol. 35,
pp. 2165-2174, 2010.
[9] B.Belkacem, A.K. Lahouari, M. Rahli, “SPWM and SVPWM control of a three level voltage inverter dedicated to
a variable speed wind turbine,” Journal of Power Technologies, vol. 97, no. 3, pp. 190-200, 2017.
[10] F. Poitiers, M. Machmoum, R. Le Doeufi and M. E. Zaim, “Control of a doubly-fed induction generator for wind
energy conversion systems,” IEEE Trans Renewable Energy, vol. 3, no. 3, pp. 373-378, 2001.
[11] H. S. Hamad, A. Hussein Ali, A. A. Abdulrazzaq, “An adaptable different-levels cascaded h-bridge inverter
analysis for PV grid-connected systems,” International Journal of Power Electronics and Drive Systems (IJPEDS),
vol. 10, no. 2, 2019.
[12] B. Hamane. M. L. Doumbia, M. Bouhamida, and M. Benghanem, “Control of Wind Turbine Based on DFIG Using
Fuzzy-PI and Sliding Mode Controllers,” Ninth International Conference on Ecological Vehicles and Renewable
Energies, pp. 1-8, 2014.
[13] A. G. Ram, S. and A. Lincoln, “Fuzzy adaptive PI controller for single input single output non-linear system,”
ARPN Journal of Engineering and Applied, Sciences, vol. 7, no. 10, pp. 1273-1280, 2012.
[14] T. Mesbahi, T. Ghennam and E. M. Berkouk, “A Doubly Fed Induction Generator for wind stand-alone power
applications (Simulation and experimental validation),” Electrical Machines (ICEM), 2012 XXth International
Conference on, pp. 2028-2033, 2012.
[15] R. Sadaoui, "Analyse et commande de la machine asynchrone à double alimentation," Université du Québec
à Trois-Rivières Service de la bibliothèque, 2013.
[16] Shanzhi Li, Haoping Wang, Yang Tian, Abdel Aitouch, John Klein, “Direct power control of DFIG wind turbine systems
based on an intelligent proportional-integral sliding mode control,” ISA Transactions, vol. 64, pp. 431-439, 2016.
[17] K. Kerrouche, A. Mezouar and L. Boumedien, “A simple and efficient maximized power control of DFIG Variable
Speed Wind Turbine,” Proceedings of the 3rd International Conference on Systems and Control, 2013.
[18] A. Bouharchouche, E. M. Berkouk, T. Ghennam and B. Tabbache, “Modeling and control of a Doubly fed
induction generator with battery supercapacitor hybrid energy storage for wind power applications,”
2013 Fourth International Conference on Power Engineering, Energy and Electrical Drives, pp. 1392 -1397, 2013.
12. Int J Elec & Comp Eng ISSN: 2088-8708
Control of the powerquality for a DFIG powered by multilevel inverters (Hachemi Hachemi)
4603
[19] B. Hamane, M. L. Doumbia, M. Bouhamida and M. Benghanem, “Direct active and reactive power control of
DFIG based WECS using PI and sliding mode controllers,” ECON 2014-40th Annual Conference of the IEEE
Industrial Electronics Society, pp. 2050-2055, 2014.
[20] A. Leredde, "Etude, Commande et Mise en Œuvre de Nouvelles Structures Multiniveaux," Thèse de doctorat de
l’Institut National Polytechnique de Toulouse (INP Toulouse), 2011.
[21] D. Floricau and G. Gateau "New Multilevel Converter for Industrial Medium-Voltage Applications,"
Journal Przeglad Elektrotechniczny (Electrical Review), pp. 26-30, 2009.
[22] F. Z. Peng, J. W. Mckeever and D. J. Adams, “A power line conditioner using cascade multilevel inverters for
distribution systems,” IEEE Transactions on Industry Applications, vol. 34, no. 6, pp. 1293-1298, 1998.
[23] A. Shamsul Rahimi A. Subki, and all, “Hardware implementation of single phase three-level cascaded h-bridge
multilevel inverter using sinusoidal pulse width modulation,” vol. 10, no. 2, 2019.
[24] J. S. Mariéthoz, "Etude formelle pour la synthèse de convertisseurs multiniveaux asymétriques: Topologies,
modulation et commande," Thèse de Doctorat, Ecole Polytechnique Fédérale de Lausanne, 2005.
[25] A. Mahrous, M. K. Metwaly and N. Elkalashy, “Performance investigation of multi-level inverter for DFIG during
grid autoreclosure operation,” International Journal of Power Electronics and Drive Systems (IJPEDS), vol. 10,
no. 1, pp. 454-462, 2019.