Abdelhafid Yahya - Academia.edu (original) (raw)
Papers by Abdelhafid Yahya
2018 Renewable Energies, Power Systems & Green Inclusive Economy (REPS-GIE), 2018
Use of photovoltaic (PV) power generation system will become more extensive in the future due to ... more Use of photovoltaic (PV) power generation system will become more extensive in the future due to anticipated cost reduction in PV technology. This paper treats with the problem of stability analysis and controlling a power system in which a synchronous generator and PV generator supply the power to an infinite bus. Firstly the investigation of the existence of the equilibrium points of the system and their stability are presented. For this problem, we derive a sufficient condition on the PV current for the existence of the equilibrium points. In addition, we analyze the stability of the equilibrium points, and show that there is only one equilibrium points which is stable. These results clarify the impact of the penetration of PV generator on the existence of the stable equilibrium points of the system. Secondly, we give the maximum electric current that the PV generator can inject into the grid without affecting its stability. The results clarify the conditions to be respected for the maximum penetration of the PV generator in the grid according to the characteristics of the transmission line and the parameters of the synchronous generator.
E3S Web of Conferences
Currently, we are trying to improve electrical energy in the world. In practice, the use of switc... more Currently, we are trying to improve electrical energy in the world. In practice, the use of switching devices is increased in the various applications. Non-linearity of loads has adverse effects on energy efficiency, power factor, etc. This increases the reactive power and oversizes the devices of the electrical installation. Several solutions are therefore proposed. Unlike passive filter, active filters work due to their small size. In this paper, work is done on the Parallel Active Power Filter (SAPF) using nonlinear control based on Lyapunov theory and PQ theory for attenuation of harmonics and reduction of imaginary power in operation of a photovoltaic system. The simulation of the circuits is implemented in MATLAB / SIMULINK. The measurements have been presented with or without SAPF filter. We start the article by modeling the different devices used, then an analysis of the PQ theory is carried out, carrying out simulations, results and interpretations. Finally, we end with a c...
2015 International Conference on Renewable Energy Research and Applications (ICRERA), 2015
In this paper, a control of a photovoltaic system connected to the grid is presented. The main co... more In this paper, a control of a photovoltaic system connected to the grid is presented. The main components of the studied system are solar arrays connected through a DC bus to a grid side inverter. Due to the instantaneous changes of solar irradiance and temperature, maximum power point tracking (MPPT) is integrated in the inverter control. The energy generated by the grid photovoltaic system is sent to the grid. This is accomplished through an efficient DC/AC conversion where the MPPT is integrated in the inverter to control active and reactive power level injected to the grid. To overcome undesirable drawbacks of hysteresis current control, and to obtain a constant switching frequency, in this paper we applied a modulated hysteresis control. The obtained results using Matlab/Simulink are presented and discussed.
2019 16th International Multi-Conference on Systems, Signals & Devices (SSD), 2019
The increased penetration of renewable energy sources to the grid has been proved to affect both ... more The increased penetration of renewable energy sources to the grid has been proved to affect both the steady state performance and the transient stability of the power system. For instance, the bus voltage magnitudes, the relative rotor angle and synchronism are the most affected system parameters during transients in the system with high penetration of photovoltaic (PV) sources. The aim of this paper is to elaborate, using sliding mode technique, an adaptive nonlinear controller that stabilizes the closed loop system whatever the penetration of PV energy sources and without resorting to the measurement of electrical power. The controlled system consists of a synchronous generator (GS), a photovoltaic generator, and an infinite bus corresponding to a large system to which the two generators are connected. It is shown, using formal analysis and simulation results, that the proposed controller achieves all the control objectives, mainly: i) tight regulation of the phase angle of the GS voltage for the infinite bus voltage, ii) good estimation of uncertain parameter, and iii) asymptotic stability of the closed loop system.
2017 International Conference on Electrical and Information Technologies (ICEIT), 2017
Partial shading (PS) in photovoltaic array is one of the main problems that can be faced when ext... more Partial shading (PS) in photovoltaic array is one of the main problems that can be faced when extracting solar energy. It takes place when certain spots of the photovoltaic (PV) array are shaded, while other parts are left uniformly irradiated. PS remarkably reduces the output power and could damage shaded cells if they are not protected. As the PS effect is not proportional to the shaded area and the P-V curve exhibits several local maximum power points, conventional maximum power point tracking (MPPT) techniques become ineffective. In this paper, we analyze the behavior of the array output power under PS throw simulation of several possible scenarios in order to approximate the I-V (P-V) characteristic and facilitate the extraction of the maximum power of the PV array.
2017 International Conference on Electrical and Information Technologies (ICEIT), 2017
In this paper, we propose an adaptive nonlinear controller for Voltage Source Inverters (VSI) use... more In this paper, we propose an adaptive nonlinear controller for Voltage Source Inverters (VSI) used in microgrids. We aim to enforce the output voltage to track a given reference even if the load resistance is unknown and time variable. After the system modeling, the controller is designed using the backstepping technique and it includes an estimation of the load resistance. Many simulations have been carried out under different conditions to validate the designed controller. The simulation results show that the elaborated controller allows a perfect tracking of the reference voltage and an asymptotic stability. It is worth mentioning that the designed controller can operate in both microgrid modes: grid connected mode and islanded mode.
Sustainable Energy Technologies and Assessments, 2020
Abstract A reliable model for photovoltaic (PV) cell/panel is of great interest; it helps to simu... more Abstract A reliable model for photovoltaic (PV) cell/panel is of great interest; it helps to simulate and better understand the behavior of PV systems. Consequently, better control and optimization of the system can be achieved. The most used models of PV cell/panel in literature are the one-diode (ODM) and double-diode (DDM) models. Their accuracy strongly depends on their parameters which must be obtained carefully. Optimization-based approaches are widely adopted for this purpose. In this context, this paper presents two main references studies: The first one focuses on optimization methods and their three basic elements: model, objective function and algorithm. The study highlights the improvement that can be made to the accuracy of the final I-V curve and to the CPU-time required for the extraction by choosing the right combination of the three elements. This is done through the analysis of more than 50 results obtained by different combinations of algorithms, objective functions and models applied to benchmark PV cells and panels widely used in literature. The best combinations are identified and recommended. The second is a detailed comparison and classification of 47 I-V curve estimation methods based on three different approaches: optimization techniques, analytical methods and explicit models of PV cells/panels.
International Journal of Modelling, Identification and Control, 2019
International Journal of Power Electronics and Drive Systems (IJPEDS), 2019
2014 IEEE Conference on Control Applications (CCA), 2014
2014 International Renewable and Sustainable Energy Conference (IRSEC), 2014
A nonlinear control methodology for three phase grid connected of photovoltaic generator is prese... more A nonlinear control methodology for three phase grid connected of photovoltaic generator is presented in this paper. It consists of a PV arrays, a voltage source inverter, a grid filter and an electric grid. The controller objectives are threefold: i) ensuring the Maximum power point tracking (MPPT) in the side of PV panels, ii) guaranteeing a power factor unit in the side of the grid, iii) ensuring the global asymptotic stability of the closed loop system. On the basis of the nonlinear model of the entire system, the controller is carried out using an approach of Lyapunov. It is formally shown, using a theoretical stability analysis and simulation results that the proposed controller satisfies all the objectives.
IFAC Proceedings Volumes, 2013
Abstract As a rapid increase in electricity demand is observed globally, distributed generation (... more Abstract As a rapid increase in electricity demand is observed globally, distributed generation (DG) based on renewable energy sources is becoming important. This paper addresses with the problem of modeling and the nonlinear control of photovoltaic/fuel cell hybrid distributed generation system (PV/FC HDGS). The power circuit topology consists of two dc–dc boost-type converters and one inverter. The outputs of the two dc–dc converters are connected to a common dc bus. The control objective is threefold: (i) global asymptotic stability of the whole closed-loop control system; (ii) achievement of MPPT of the PV array; (iii) ensuring a tight regulation of the dc-bus voltage. These objectives must be met despite changes of the climatic variables (temperature and radiation) and the power demand of the load. It is clearly shown, using formal analysis and simulations that the designed controller meets all the objectives.
Sustainable Energy, Grids and Networks, Mar 1, 2020
IJPEDS VOL 15 NO 3 SEPTEMBER 2024 by Abdelhafid Yahya
International Journal of Power Electronics and Drive Systems (IJPEDS), 2024
This paper presents a nonlinear control in the stationary αβ reference frame for single-stage thr... more This paper presents a nonlinear control in the stationary αβ reference frame for single-stage three-phase grid-connected photovoltaic systems. The system under study consists of a photovoltaic generator (PVG), a three-phase inverter, and an LCL-filter on the grid side. The main control objectives are to extract the maximum power from the PVG and deliver that power into the grid with high-quality power i.e. unity power factor (UPF). In order to achieve these objectives, a nonlinear controller is designed by using backstepping technique. The performance of this controller is evaluated under standard and variable atmospheric conditions. Simulation results demonstrate that the proposed controller has successfully met all the specified objectives. This study highlights the potential of using the nonlinear control based on backstepping technique in photovoltaic systems with LCL-filters. The modeling and simulation of the complete system are carried out using MATLAB/Simulink environment.
2018 Renewable Energies, Power Systems & Green Inclusive Economy (REPS-GIE), 2018
Use of photovoltaic (PV) power generation system will become more extensive in the future due to ... more Use of photovoltaic (PV) power generation system will become more extensive in the future due to anticipated cost reduction in PV technology. This paper treats with the problem of stability analysis and controlling a power system in which a synchronous generator and PV generator supply the power to an infinite bus. Firstly the investigation of the existence of the equilibrium points of the system and their stability are presented. For this problem, we derive a sufficient condition on the PV current for the existence of the equilibrium points. In addition, we analyze the stability of the equilibrium points, and show that there is only one equilibrium points which is stable. These results clarify the impact of the penetration of PV generator on the existence of the stable equilibrium points of the system. Secondly, we give the maximum electric current that the PV generator can inject into the grid without affecting its stability. The results clarify the conditions to be respected for the maximum penetration of the PV generator in the grid according to the characteristics of the transmission line and the parameters of the synchronous generator.
E3S Web of Conferences
Currently, we are trying to improve electrical energy in the world. In practice, the use of switc... more Currently, we are trying to improve electrical energy in the world. In practice, the use of switching devices is increased in the various applications. Non-linearity of loads has adverse effects on energy efficiency, power factor, etc. This increases the reactive power and oversizes the devices of the electrical installation. Several solutions are therefore proposed. Unlike passive filter, active filters work due to their small size. In this paper, work is done on the Parallel Active Power Filter (SAPF) using nonlinear control based on Lyapunov theory and PQ theory for attenuation of harmonics and reduction of imaginary power in operation of a photovoltaic system. The simulation of the circuits is implemented in MATLAB / SIMULINK. The measurements have been presented with or without SAPF filter. We start the article by modeling the different devices used, then an analysis of the PQ theory is carried out, carrying out simulations, results and interpretations. Finally, we end with a c...
2015 International Conference on Renewable Energy Research and Applications (ICRERA), 2015
In this paper, a control of a photovoltaic system connected to the grid is presented. The main co... more In this paper, a control of a photovoltaic system connected to the grid is presented. The main components of the studied system are solar arrays connected through a DC bus to a grid side inverter. Due to the instantaneous changes of solar irradiance and temperature, maximum power point tracking (MPPT) is integrated in the inverter control. The energy generated by the grid photovoltaic system is sent to the grid. This is accomplished through an efficient DC/AC conversion where the MPPT is integrated in the inverter to control active and reactive power level injected to the grid. To overcome undesirable drawbacks of hysteresis current control, and to obtain a constant switching frequency, in this paper we applied a modulated hysteresis control. The obtained results using Matlab/Simulink are presented and discussed.
2019 16th International Multi-Conference on Systems, Signals & Devices (SSD), 2019
The increased penetration of renewable energy sources to the grid has been proved to affect both ... more The increased penetration of renewable energy sources to the grid has been proved to affect both the steady state performance and the transient stability of the power system. For instance, the bus voltage magnitudes, the relative rotor angle and synchronism are the most affected system parameters during transients in the system with high penetration of photovoltaic (PV) sources. The aim of this paper is to elaborate, using sliding mode technique, an adaptive nonlinear controller that stabilizes the closed loop system whatever the penetration of PV energy sources and without resorting to the measurement of electrical power. The controlled system consists of a synchronous generator (GS), a photovoltaic generator, and an infinite bus corresponding to a large system to which the two generators are connected. It is shown, using formal analysis and simulation results, that the proposed controller achieves all the control objectives, mainly: i) tight regulation of the phase angle of the GS voltage for the infinite bus voltage, ii) good estimation of uncertain parameter, and iii) asymptotic stability of the closed loop system.
2017 International Conference on Electrical and Information Technologies (ICEIT), 2017
Partial shading (PS) in photovoltaic array is one of the main problems that can be faced when ext... more Partial shading (PS) in photovoltaic array is one of the main problems that can be faced when extracting solar energy. It takes place when certain spots of the photovoltaic (PV) array are shaded, while other parts are left uniformly irradiated. PS remarkably reduces the output power and could damage shaded cells if they are not protected. As the PS effect is not proportional to the shaded area and the P-V curve exhibits several local maximum power points, conventional maximum power point tracking (MPPT) techniques become ineffective. In this paper, we analyze the behavior of the array output power under PS throw simulation of several possible scenarios in order to approximate the I-V (P-V) characteristic and facilitate the extraction of the maximum power of the PV array.
2017 International Conference on Electrical and Information Technologies (ICEIT), 2017
In this paper, we propose an adaptive nonlinear controller for Voltage Source Inverters (VSI) use... more In this paper, we propose an adaptive nonlinear controller for Voltage Source Inverters (VSI) used in microgrids. We aim to enforce the output voltage to track a given reference even if the load resistance is unknown and time variable. After the system modeling, the controller is designed using the backstepping technique and it includes an estimation of the load resistance. Many simulations have been carried out under different conditions to validate the designed controller. The simulation results show that the elaborated controller allows a perfect tracking of the reference voltage and an asymptotic stability. It is worth mentioning that the designed controller can operate in both microgrid modes: grid connected mode and islanded mode.
Sustainable Energy Technologies and Assessments, 2020
Abstract A reliable model for photovoltaic (PV) cell/panel is of great interest; it helps to simu... more Abstract A reliable model for photovoltaic (PV) cell/panel is of great interest; it helps to simulate and better understand the behavior of PV systems. Consequently, better control and optimization of the system can be achieved. The most used models of PV cell/panel in literature are the one-diode (ODM) and double-diode (DDM) models. Their accuracy strongly depends on their parameters which must be obtained carefully. Optimization-based approaches are widely adopted for this purpose. In this context, this paper presents two main references studies: The first one focuses on optimization methods and their three basic elements: model, objective function and algorithm. The study highlights the improvement that can be made to the accuracy of the final I-V curve and to the CPU-time required for the extraction by choosing the right combination of the three elements. This is done through the analysis of more than 50 results obtained by different combinations of algorithms, objective functions and models applied to benchmark PV cells and panels widely used in literature. The best combinations are identified and recommended. The second is a detailed comparison and classification of 47 I-V curve estimation methods based on three different approaches: optimization techniques, analytical methods and explicit models of PV cells/panels.
International Journal of Modelling, Identification and Control, 2019
International Journal of Power Electronics and Drive Systems (IJPEDS), 2019
2014 IEEE Conference on Control Applications (CCA), 2014
2014 International Renewable and Sustainable Energy Conference (IRSEC), 2014
A nonlinear control methodology for three phase grid connected of photovoltaic generator is prese... more A nonlinear control methodology for three phase grid connected of photovoltaic generator is presented in this paper. It consists of a PV arrays, a voltage source inverter, a grid filter and an electric grid. The controller objectives are threefold: i) ensuring the Maximum power point tracking (MPPT) in the side of PV panels, ii) guaranteeing a power factor unit in the side of the grid, iii) ensuring the global asymptotic stability of the closed loop system. On the basis of the nonlinear model of the entire system, the controller is carried out using an approach of Lyapunov. It is formally shown, using a theoretical stability analysis and simulation results that the proposed controller satisfies all the objectives.
IFAC Proceedings Volumes, 2013
Abstract As a rapid increase in electricity demand is observed globally, distributed generation (... more Abstract As a rapid increase in electricity demand is observed globally, distributed generation (DG) based on renewable energy sources is becoming important. This paper addresses with the problem of modeling and the nonlinear control of photovoltaic/fuel cell hybrid distributed generation system (PV/FC HDGS). The power circuit topology consists of two dc–dc boost-type converters and one inverter. The outputs of the two dc–dc converters are connected to a common dc bus. The control objective is threefold: (i) global asymptotic stability of the whole closed-loop control system; (ii) achievement of MPPT of the PV array; (iii) ensuring a tight regulation of the dc-bus voltage. These objectives must be met despite changes of the climatic variables (temperature and radiation) and the power demand of the load. It is clearly shown, using formal analysis and simulations that the designed controller meets all the objectives.
Sustainable Energy, Grids and Networks, Mar 1, 2020
International Journal of Power Electronics and Drive Systems (IJPEDS), 2024
This paper presents a nonlinear control in the stationary αβ reference frame for single-stage thr... more This paper presents a nonlinear control in the stationary αβ reference frame for single-stage three-phase grid-connected photovoltaic systems. The system under study consists of a photovoltaic generator (PVG), a three-phase inverter, and an LCL-filter on the grid side. The main control objectives are to extract the maximum power from the PVG and deliver that power into the grid with high-quality power i.e. unity power factor (UPF). In order to achieve these objectives, a nonlinear controller is designed by using backstepping technique. The performance of this controller is evaluated under standard and variable atmospheric conditions. Simulation results demonstrate that the proposed controller has successfully met all the specified objectives. This study highlights the potential of using the nonlinear control based on backstepping technique in photovoltaic systems with LCL-filters. The modeling and simulation of the complete system are carried out using MATLAB/Simulink environment.