This document summarizes an article from the International Journal of Electrical and Computer Engineering that presents an adaptive fuzzy PI current controller for a grid-interactive photovoltaic inverter. The controller uses fuzzy logic to update the gains of the proportional-integral controller based on the error current and change in error current. This allows the controller to maintain good dynamic response and low steady-state error under varying operating conditions. Simulation results show the controller enables the inverter to track a step change in the reference current with less transient behavior and zero steady-state error while keeping the total harmonic distortion of the grid current below 5%.
This work includes the establishment of a Photovoltaic system connected to the grid by means of an inverter. The fundamental goal of the work is to incorporate an advanced active power flow management scheme in order to adopt load at any weather condition along with the advantage of maximum active power flow and zero harmonics from PV inverter to the grid. The outcome of analysis and control design of grid connected PV inverter using a Proportional-Integral (PI) control technique is based on synchronous dq rotating reference frame so as to achieve maximum output voltage and record the active power. It has been observed that the model provides a better rate of stability as compared to the existing topology.
In this paper the harmonic stability is investigated for multi paralleled three-phase photovoltaic inverters connected to grid. The causes to harmonically stabilize/destabilize the multi-paralleled PV inverters when tied to the grid isanalysed by the impedance-based stability criterion (IBSC). In this paper stability of the system is investigated by varying the grid inductance with constant grid resistance and also by varying load impedance while maintaining grid inductance constant. Stability of the multiple three phase inverters tied to the grid with different grid impedance, inductance value inparticular are analyzed. Overall system is stable up to grid inductance of5mH even though there is change in load admittance. It is concluded that system stability depends only on grid impedance. It is verified with Matlab Simulations.
Improvement of Power Quality using Fuzzy Logic Controller in Grid Connected P...IAES-IJPEDS
In this paper, the design of combined operation of UPQC and PV-ARRAY is designed. The proposed system is composed of series and shunt inverters connected back to back by a dc-link to which pv-array is connected. This system is able to compensate voltage and current related problems both in inter-connected mode and islanding mode by injecting active power to grid. The fundamental aspect is that the power electronic devices (PE) and sensitive equipments (SE) are normally designed to work in non-polluted power system, so they would suffer from malfunctions when supply voltage is not pure sinusoidal. Thus this proposed operating strategy with flexible operation mode improves the power quality of the grid system combining photovoltaic array with a control of unified power quality conditioner. Pulse Width Modulation (PWM) is used in both three phase four leg inverters. A Proportional Integral (PI) and Fuzzy Logic Controllers are used for power quality improvement by reducing the distortions in the output power. The simulated results were compared among the two controller’s strategies With pi controller and fuzzy logic controller
Power quality is a concern for utility and grid operators due to a large penetration of intermittent and stochastic renewable power generation sources. One of the major concerns, when designing and controlling grid-feeding photovoltaic (PV) inverters is meeting the grid requirements. International grid requirements demand low-voltage ride-through (LVRT) capability and maintaining grid functionality during fault conditions. This paper presents a comprehensive review for several control techniques to assure the LVRT capability of grid-feeding converters as well as discussing their respective advantages and limitations in detail. Areas for further research are identified afterwards. Finally, the conclusion gives a brief summary and critique of the findings.
Comparison of upqc and dvr in wind turbine fed fsig under asymmetric faultselelijjournal
This paper presents the mitigation of faults in wind turbine connected fixed speed induction generator using unified power quality conditioner and static compensator. The UPQC consists of shunt and series converters connected back-to-back through a dc-to-dc step up converter. The presence of the dc-to-dc step converter permits the UPQC to compensate faults for long duration. The series converter is connected to the supply side whereas the shunt converter is connected to the load side. The control system of the proposed UPQC is based on Id-Iq theory. The DVR consists of shunt and series converters connected back-to-back through a dc-to-dc step up converter. The presence of the dc-to-dc step converter permits the DVR to compensate faults for long duration. The series converter is connected to the supply side whereas the shunt converter is connected to the load side. The control system of the proposed DVR is based on
hysteresis voltage controlThe proposed wind turbine fed fixed speed induction generator is evaluated and simulated using MATLAB/SIMULINK environment with UPQC and DVR under asymmetric faults
This work includes the establishment of a Photovoltaic system connected to the grid by means of an inverter. The fundamental goal of the work is to incorporate an advanced active power flow management scheme in order to adopt load at any weather condition along with the advantage of maximum active power flow and zero harmonics from PV inverter to the grid. The outcome of analysis and control design of grid connected PV inverter using a Proportional-Integral (PI) control technique is based on synchronous dq rotating reference frame so as to achieve maximum output voltage and record the active power. It has been observed that the model provides a better rate of stability as compared to the existing topology.
In this paper the harmonic stability is investigated for multi paralleled three-phase photovoltaic inverters connected to grid. The causes to harmonically stabilize/destabilize the multi-paralleled PV inverters when tied to the grid isanalysed by the impedance-based stability criterion (IBSC). In this paper stability of the system is investigated by varying the grid inductance with constant grid resistance and also by varying load impedance while maintaining grid inductance constant. Stability of the multiple three phase inverters tied to the grid with different grid impedance, inductance value inparticular are analyzed. Overall system is stable up to grid inductance of5mH even though there is change in load admittance. It is concluded that system stability depends only on grid impedance. It is verified with Matlab Simulations.
Improvement of Power Quality using Fuzzy Logic Controller in Grid Connected P...IAES-IJPEDS
In this paper, the design of combined operation of UPQC and PV-ARRAY is designed. The proposed system is composed of series and shunt inverters connected back to back by a dc-link to which pv-array is connected. This system is able to compensate voltage and current related problems both in inter-connected mode and islanding mode by injecting active power to grid. The fundamental aspect is that the power electronic devices (PE) and sensitive equipments (SE) are normally designed to work in non-polluted power system, so they would suffer from malfunctions when supply voltage is not pure sinusoidal. Thus this proposed operating strategy with flexible operation mode improves the power quality of the grid system combining photovoltaic array with a control of unified power quality conditioner. Pulse Width Modulation (PWM) is used in both three phase four leg inverters. A Proportional Integral (PI) and Fuzzy Logic Controllers are used for power quality improvement by reducing the distortions in the output power. The simulated results were compared among the two controller’s strategies With pi controller and fuzzy logic controller
Power quality is a concern for utility and grid operators due to a large penetration of intermittent and stochastic renewable power generation sources. One of the major concerns, when designing and controlling grid-feeding photovoltaic (PV) inverters is meeting the grid requirements. International grid requirements demand low-voltage ride-through (LVRT) capability and maintaining grid functionality during fault conditions. This paper presents a comprehensive review for several control techniques to assure the LVRT capability of grid-feeding converters as well as discussing their respective advantages and limitations in detail. Areas for further research are identified afterwards. Finally, the conclusion gives a brief summary and critique of the findings.
Comparison of upqc and dvr in wind turbine fed fsig under asymmetric faultselelijjournal
This paper presents the mitigation of faults in wind turbine connected fixed speed induction generator using unified power quality conditioner and static compensator. The UPQC consists of shunt and series converters connected back-to-back through a dc-to-dc step up converter. The presence of the dc-to-dc step converter permits the UPQC to compensate faults for long duration. The series converter is connected to the supply side whereas the shunt converter is connected to the load side. The control system of the proposed UPQC is based on Id-Iq theory. The DVR consists of shunt and series converters connected back-to-back through a dc-to-dc step up converter. The presence of the dc-to-dc step converter permits the DVR to compensate faults for long duration. The series converter is connected to the supply side whereas the shunt converter is connected to the load side. The control system of the proposed DVR is based on
hysteresis voltage controlThe proposed wind turbine fed fixed speed induction generator is evaluated and simulated using MATLAB/SIMULINK environment with UPQC and DVR under asymmetric faults
Improving Stability of Utility-Tied Wind Generators using Dynamic Voltage Res...IJMTST Journal
The generation of electricity using wind power is significantly increasing and has received considerable attention in recent years. One important problem with the induction generator based wind farms is that they are vulnerable to voltage disturbances and short circuit faults. Any such disturbance may cause wind farm outages. Since wind power contribution is in considerable percentage, such outages may lead to power system stability issues and also violate the grid code requirements. Thus, improving the reliability of wind farms is essential to maintain the stability of the system. The proposed strategy is to use Dynamic Voltage Restorer (DVR), which is one of the promising devices to compensate the voltage disturbance and to improve the stability of the system. It provides the wind generator with the fault ride through capability and improves the reliability of the system. Fuzzy Logic controller is used as a controller in order to control the dc link voltages and to reduce the harmonics. Simulation results for a 2 MW wind turbine are presented, especially for asymmetrical grid faults. They show the effectiveness of the DVR in comparison to the low voltage ride-through of the DFIG using a crowbar that does not allow continuous reactive power production. Extensive simulation results are included to illustrate the operation of DVR and fault compensation.
Modeling & analysis of standalone photovoltaic systemeSAT Journals
Abstract This paper represents the three phase Photovoltaic system connected with variable load in a standalone mode’s mathematical modeling using MATLAB/ Simulink environment. The system consist of a PV Array, Boost converter, three phase inverter and its control to maintain load in standalone mode. The 40 kW systems at the college site is under the study with a variable inductive load of 30kW which has to be fed by PV system in continuous mode .This paper gives analysis of each components of system while maintaining the load. The constant and boosted DC voltage is obtained with the help of boost converter from PV Array. The three phase IGBT inverter PWM control scheme is proposed here to normalize the voltage imbalance during variable load. Keywords: Photovoltaic System, Boost Converter, IGBT Inverter, and PI Controller etc…
Control of Two Stage PV Power System under the Unbalanced Three Phase Grid Vo...ijtsrd
This paper proposes a dynamic power decoupling DPD strategy for the three phase grid tied PV power system without increasing the dc link capacitance. Under normal condition, the interleaved boost converter will extract the maximum power point MPP from the PV array and the three phase inverter will inject the power to the grid. During the unbalanced grid fault scenario, the input power and current of the interleaved boost converter will be controlled by the proposed DPD to achieve the power decoupling capability as well as to eliminate the dc link voltage oscillation. The proposed work has been carried out in MATLAB, and the results are presented. Manasa | Nirmaladevi ""Control of Two Stage PV Power System under the Unbalanced Three-Phase Grid Voltages"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-4 | Issue-2 , February 2020,
URL: https://www.ijtsrd.com/papers/ijtsrd30091.pdf
Paper Url : https://www.ijtsrd.com/engineering/electrical-engineering/30091/control-of-two-stage-pv-power-system-under-the-unbalanced-three-phase-grid-voltages/manasa
Design Fuzzy-PI Based Controller for Load Frequency Control of Thermal - Ther...ijtsrd
This paper presents how to design proportional integral controller and Fuzzy-PI based controller for efficiently load frequency control. Loads on the electrical system always vary in relation to that time, which results in diversity of frequency, causing frequency control problems to be loaded. The frequency difference is highly undesirable and the maximum allowable difference in frequency is ± 0.5 Hz. This paper load frequency control is done by PI controller, which is a conventional controller. This type of controller is slow and the controller does not allow the designer to keep in mind the potential change in operating conditions and non-linearity in the generator unit. To overcome these flaws, new intelligent controllers like Fuzzy-PI Controller are presented to extinguish tie-line power due to deviation in frequency and various load disturbances. The effectiveness of the proposed controller has been confirmed using the MATLAB SIMULINK software. The results show that the PI-fuzzy controller provides fast response, little undershoots and negligible overshoot with small state transfer time to reach the final stable position. Ajay Kumar Maurya | Dr. G. K. Banerjee | Dr. Piush Kumar "Design Fuzzy-PI Based Controller for Load Frequency Control of Thermal - Thermal Area Interconnected Power System" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-1 , December 2018, URL: http://www.ijtsrd.com/papers/ijtsrd19164.pdf
http://www.ijtsrd.com/engineering/electrical-engineering/19164/design-fuzzy-pi-based-controller-for-load-frequency-control-of-thermal---thermal-area-interconnected-power-system/ajay-kumar-maurya
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
This paper presents a grid-connected photovoltaic (PV) interface for delivering both active and reactive powers. The PV interface employs H-bridge topology DC-DC converter and inverter with analog control technology. The power flow is controlled solely by the adjustable DC output voltage of the DC to DC converter. In order to evaluate the PV interface system’s performances, it is tested by delivering power to the grid with low pawer factor. The experimental results show that at 300W active load, the inverter could deliver the reactive power of 400VAR. The PV interface could also produce very low harmonic voltage and current distorsions. The laboratory measurements show that the total harmonic distortions of inverter output voltage and current are 0.46% and 0.05%, respectively.
Performance Improvement of a Grid Connected Wind Farm SystemIOSRJEEE
Renewable energy sources are becoming more promising means of green energy production. But the increasingly penetration level of wind energy into existing power system presents many technical challenges. Power quality is a measure of the system performance. It requires consideration of problems like voltage regulation, stability, harmonics etc. This paper presents an overview of grid connected system and analysis of its stability. The system is assumed with fixed speed Induction generator integrated to a weak grid. Change and improvement in performance is observed with various FACT devices. The simulation model has been developed in MATLAB/SIMULINK R2016a.
SIMULATION OF IMPROVEMENT OF POWER QUALITY USING STATCOM-CONTROL SCHEME WITH ...ijiert bestjournal
The use of wind energy generation in electrical gri d is increasing worldwide. Injection of the wind power into an electric grid affects the power quality. The generated wind power is always not constant due to its time varying nature and causing stability problems. This weak interconnection of wind generating source in the el ectrical network affects the power quality and reliability. In this paper the power quality pr oblem due to installation of wind turbine with the grid is determine. In this proposed scheme Static Compensator (STATCOM) is connected at a point of common coupling to reduce t he power quality problems. The STATCOM gives reactive power support to wind genera tor and also load. The proposed system maintains the grid voltage free from distort ion and harmonics. In this paper the effect of STATCOM is presented. The behavior of STATCOM is studied under reactive l oading condition.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
This document proposes a photovoltaic (PV) based single-phase dynamic voltage restoration (DVR) device, it eliminates both sag and swell voltage and compensates for power. The proposed system requires a power source to compensate for the sag/swell voltage. This system has found a simple topology for the DVR that uses PV with two DC-DC boosts converters as the DC power source for the dynamic voltage conservator. The DC/DC boost converter powered by the PV generator is used to increase the voltage to meet the DC bus voltage requirements of the single-branch voltage source inverter (VSI). This system uses renewable energy; saves energy accordingly and supplies power to critical/sensitive loads. The control method used in this work is a Sliding Mode Control (SMC) method and relies on a phase locked loop (PLL) used to control the active filter. The effectiveness of the suggested method is confirmed by the MATLAB/Simulink® simulation results and some prototype experiments. These results show the capacity of the proposed DC link control.
Control strategies for seamless transfer between the grid-connected and isla...IJECEIAES
Design of control strategies for Distributed generation systems is very important to achieve smoother transition between the grid connected and islanding modes of operation. The transition between these two modes of operation should be seamless, without any severe transients during the changeover. In this paper, two different control strategies namely inverter output current control and indirect grid current control for the seamless transfer between the modes of operation has been explored for the suitability. The design and analysis of the cascaded control loops based on Proportional Integral (PI) controller has been dealt in detail for both inverter output current control and indirect grid current control strategy. Control parameters are designed using the control system toolbox in MATLAB. A 10kW grid connected microgrid system has been designed and simulated in MATLAB/Simulink and the results are presented under grid connected operation, islanding operation and the transition between the modes considering fault condition in the grid side. The simulation studies are carried out using both the control strategies and the results are presented to validate the design methodology.
Non-linear tons are normally affected by power quality (PQ) problems. Harmonic currents make system resonance, capacitor overloading, and decrease in efficiency. Voltage sags are usually happening power quality difficulties in electrical systems. The unified power quality conditioner (UPQC) is one of the FACTS controllers used for modifying the effect of voltage sags. The series compensator in the UPQC is for quadrature type of voltage inoculation. So that at steady state the series compensator not ever ingests active power. The proposed method introduces a low power rating series compensator that injects the voltage which perfectly recompenses the power quality problem of the system. The addition of fuzzy logic controller with the conservative UPQC decreases the voltage sag levels in the output voltage and also develops the power factor. The control circuit is aimed using fuzzy logic controller and simulated using MATLAB/SIMULINK.
The growing demand for electricity and the increasing integration of clean energies into the electrical grids requires the multiplication and reinforcement of high-voltage direct current (HVDC) projects throughout the world and demonstrates the interest in this electricity transmission technology. The transmitting system of the voltage source converter-high-voltage direct current (VSC-HVDC) consists primarily of two converter stations that are connected by a dc cable. In this paper, a nonlinear control based on the backstepping approach is proposed to improve the dynamic performance of a VSC-HVDC transmission system, these transport systems are characterized by different complexities such as parametric uncertainties, coupled state variables, neglected dynamics, presents a very interesting research topic. Our contribution through adaptive control based on the backstepping approach allows regulating the direct current (DC) bus voltage and the active and reactive powers of the converter stations. Finally, the validity of the proposed control has been verified under various operating conditions by simulation in the MATLAB/Simulink environment.
Single Phase PV Grid-Connected in Smart Household Energy System with Anticipa...IJPEDS-IAES
This paper proposes an algorithm of Smart household energy systems to anticipate fault conditions in power system grid. Single phase PV grid- connected in smart household energy system is a smart system that determines electrical supply conditions to the load in residential electrical system. The smart system is consisted of two voltage source, conventional electricity system from national electricity provider as preferred source and photovoltaic as the alternative source. In smart system, fault conditions can be anticipated by selecting the appropriate voltage sources to supply the load. The condition of smart system can be described in power flow regulation to the load by detection and identification of amplitude, phase angle, and frequency of the voltage source compared to the system reference. The system mechanism is based on detection of voltage source using static transfer switch (STS) with phase locked loop (PLL) as voltage detection algorithm which output is used to determine decision logic algorithm for switching conditions. The results show that conditions of smart power system flow can be obtained based on voltage source selection in decision logic when fault condition occurs.
A novel power converter that can perform both voltage and frequency conversion was proposed. Inappropriate power supply can damage sensitive sub-components and render the connected device inoperable. Henceforth, the proposed voltage–frequency converter acts as an interface to plug any electrical device directly into an electrical socket and provide the voltage and frequency required. The converter used a synchronous reference frame proportional–integral (SRFPI) controller to regulate the instantaneous output voltage and to improve steady state performance. Because the PI controller works together with the synchronous reference frame controller, it is difficult to tune the PI control parameters. To overcome this issue, a new meta heuristic optimization technique called lightening search algorithm (LSA) optimization was used to identify the optimum PI parameter values. A detailed description of the system operation and control strategy was presented. Finally, the performance of the converter was analyzed and verified by simulation and experimental results. The experimental result has shown that the proposed system has satisfactory output voltage and frequency under different input voltages.
This slide presents the control aspects of Energy Storage System in Microgrid. Later I will discuss about the control strategy with integration to DGs and EVs.
Improving Stability of Utility-Tied Wind Generators using Dynamic Voltage Res...IJMTST Journal
The generation of electricity using wind power is significantly increasing and has received considerable attention in recent years. One important problem with the induction generator based wind farms is that they are vulnerable to voltage disturbances and short circuit faults. Any such disturbance may cause wind farm outages. Since wind power contribution is in considerable percentage, such outages may lead to power system stability issues and also violate the grid code requirements. Thus, improving the reliability of wind farms is essential to maintain the stability of the system. The proposed strategy is to use Dynamic Voltage Restorer (DVR), which is one of the promising devices to compensate the voltage disturbance and to improve the stability of the system. It provides the wind generator with the fault ride through capability and improves the reliability of the system. Fuzzy Logic controller is used as a controller in order to control the dc link voltages and to reduce the harmonics. Simulation results for a 2 MW wind turbine are presented, especially for asymmetrical grid faults. They show the effectiveness of the DVR in comparison to the low voltage ride-through of the DFIG using a crowbar that does not allow continuous reactive power production. Extensive simulation results are included to illustrate the operation of DVR and fault compensation.
Modeling & analysis of standalone photovoltaic systemeSAT Journals
Abstract This paper represents the three phase Photovoltaic system connected with variable load in a standalone mode’s mathematical modeling using MATLAB/ Simulink environment. The system consist of a PV Array, Boost converter, three phase inverter and its control to maintain load in standalone mode. The 40 kW systems at the college site is under the study with a variable inductive load of 30kW which has to be fed by PV system in continuous mode .This paper gives analysis of each components of system while maintaining the load. The constant and boosted DC voltage is obtained with the help of boost converter from PV Array. The three phase IGBT inverter PWM control scheme is proposed here to normalize the voltage imbalance during variable load. Keywords: Photovoltaic System, Boost Converter, IGBT Inverter, and PI Controller etc…
Control of Two Stage PV Power System under the Unbalanced Three Phase Grid Vo...ijtsrd
This paper proposes a dynamic power decoupling DPD strategy for the three phase grid tied PV power system without increasing the dc link capacitance. Under normal condition, the interleaved boost converter will extract the maximum power point MPP from the PV array and the three phase inverter will inject the power to the grid. During the unbalanced grid fault scenario, the input power and current of the interleaved boost converter will be controlled by the proposed DPD to achieve the power decoupling capability as well as to eliminate the dc link voltage oscillation. The proposed work has been carried out in MATLAB, and the results are presented. Manasa | Nirmaladevi ""Control of Two Stage PV Power System under the Unbalanced Three-Phase Grid Voltages"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-4 | Issue-2 , February 2020,
URL: https://www.ijtsrd.com/papers/ijtsrd30091.pdf
Paper Url : https://www.ijtsrd.com/engineering/electrical-engineering/30091/control-of-two-stage-pv-power-system-under-the-unbalanced-three-phase-grid-voltages/manasa
Design Fuzzy-PI Based Controller for Load Frequency Control of Thermal - Ther...ijtsrd
This paper presents how to design proportional integral controller and Fuzzy-PI based controller for efficiently load frequency control. Loads on the electrical system always vary in relation to that time, which results in diversity of frequency, causing frequency control problems to be loaded. The frequency difference is highly undesirable and the maximum allowable difference in frequency is ± 0.5 Hz. This paper load frequency control is done by PI controller, which is a conventional controller. This type of controller is slow and the controller does not allow the designer to keep in mind the potential change in operating conditions and non-linearity in the generator unit. To overcome these flaws, new intelligent controllers like Fuzzy-PI Controller are presented to extinguish tie-line power due to deviation in frequency and various load disturbances. The effectiveness of the proposed controller has been confirmed using the MATLAB SIMULINK software. The results show that the PI-fuzzy controller provides fast response, little undershoots and negligible overshoot with small state transfer time to reach the final stable position. Ajay Kumar Maurya | Dr. G. K. Banerjee | Dr. Piush Kumar "Design Fuzzy-PI Based Controller for Load Frequency Control of Thermal - Thermal Area Interconnected Power System" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-1 , December 2018, URL: http://www.ijtsrd.com/papers/ijtsrd19164.pdf
http://www.ijtsrd.com/engineering/electrical-engineering/19164/design-fuzzy-pi-based-controller-for-load-frequency-control-of-thermal---thermal-area-interconnected-power-system/ajay-kumar-maurya
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
This paper presents a grid-connected photovoltaic (PV) interface for delivering both active and reactive powers. The PV interface employs H-bridge topology DC-DC converter and inverter with analog control technology. The power flow is controlled solely by the adjustable DC output voltage of the DC to DC converter. In order to evaluate the PV interface system’s performances, it is tested by delivering power to the grid with low pawer factor. The experimental results show that at 300W active load, the inverter could deliver the reactive power of 400VAR. The PV interface could also produce very low harmonic voltage and current distorsions. The laboratory measurements show that the total harmonic distortions of inverter output voltage and current are 0.46% and 0.05%, respectively.
Performance Improvement of a Grid Connected Wind Farm SystemIOSRJEEE
Renewable energy sources are becoming more promising means of green energy production. But the increasingly penetration level of wind energy into existing power system presents many technical challenges. Power quality is a measure of the system performance. It requires consideration of problems like voltage regulation, stability, harmonics etc. This paper presents an overview of grid connected system and analysis of its stability. The system is assumed with fixed speed Induction generator integrated to a weak grid. Change and improvement in performance is observed with various FACT devices. The simulation model has been developed in MATLAB/SIMULINK R2016a.
SIMULATION OF IMPROVEMENT OF POWER QUALITY USING STATCOM-CONTROL SCHEME WITH ...ijiert bestjournal
The use of wind energy generation in electrical gri d is increasing worldwide. Injection of the wind power into an electric grid affects the power quality. The generated wind power is always not constant due to its time varying nature and causing stability problems. This weak interconnection of wind generating source in the el ectrical network affects the power quality and reliability. In this paper the power quality pr oblem due to installation of wind turbine with the grid is determine. In this proposed scheme Static Compensator (STATCOM) is connected at a point of common coupling to reduce t he power quality problems. The STATCOM gives reactive power support to wind genera tor and also load. The proposed system maintains the grid voltage free from distort ion and harmonics. In this paper the effect of STATCOM is presented. The behavior of STATCOM is studied under reactive l oading condition.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
This document proposes a photovoltaic (PV) based single-phase dynamic voltage restoration (DVR) device, it eliminates both sag and swell voltage and compensates for power. The proposed system requires a power source to compensate for the sag/swell voltage. This system has found a simple topology for the DVR that uses PV with two DC-DC boosts converters as the DC power source for the dynamic voltage conservator. The DC/DC boost converter powered by the PV generator is used to increase the voltage to meet the DC bus voltage requirements of the single-branch voltage source inverter (VSI). This system uses renewable energy; saves energy accordingly and supplies power to critical/sensitive loads. The control method used in this work is a Sliding Mode Control (SMC) method and relies on a phase locked loop (PLL) used to control the active filter. The effectiveness of the suggested method is confirmed by the MATLAB/Simulink® simulation results and some prototype experiments. These results show the capacity of the proposed DC link control.
Control strategies for seamless transfer between the grid-connected and isla...IJECEIAES
Design of control strategies for Distributed generation systems is very important to achieve smoother transition between the grid connected and islanding modes of operation. The transition between these two modes of operation should be seamless, without any severe transients during the changeover. In this paper, two different control strategies namely inverter output current control and indirect grid current control for the seamless transfer between the modes of operation has been explored for the suitability. The design and analysis of the cascaded control loops based on Proportional Integral (PI) controller has been dealt in detail for both inverter output current control and indirect grid current control strategy. Control parameters are designed using the control system toolbox in MATLAB. A 10kW grid connected microgrid system has been designed and simulated in MATLAB/Simulink and the results are presented under grid connected operation, islanding operation and the transition between the modes considering fault condition in the grid side. The simulation studies are carried out using both the control strategies and the results are presented to validate the design methodology.
Non-linear tons are normally affected by power quality (PQ) problems. Harmonic currents make system resonance, capacitor overloading, and decrease in efficiency. Voltage sags are usually happening power quality difficulties in electrical systems. The unified power quality conditioner (UPQC) is one of the FACTS controllers used for modifying the effect of voltage sags. The series compensator in the UPQC is for quadrature type of voltage inoculation. So that at steady state the series compensator not ever ingests active power. The proposed method introduces a low power rating series compensator that injects the voltage which perfectly recompenses the power quality problem of the system. The addition of fuzzy logic controller with the conservative UPQC decreases the voltage sag levels in the output voltage and also develops the power factor. The control circuit is aimed using fuzzy logic controller and simulated using MATLAB/SIMULINK.
The growing demand for electricity and the increasing integration of clean energies into the electrical grids requires the multiplication and reinforcement of high-voltage direct current (HVDC) projects throughout the world and demonstrates the interest in this electricity transmission technology. The transmitting system of the voltage source converter-high-voltage direct current (VSC-HVDC) consists primarily of two converter stations that are connected by a dc cable. In this paper, a nonlinear control based on the backstepping approach is proposed to improve the dynamic performance of a VSC-HVDC transmission system, these transport systems are characterized by different complexities such as parametric uncertainties, coupled state variables, neglected dynamics, presents a very interesting research topic. Our contribution through adaptive control based on the backstepping approach allows regulating the direct current (DC) bus voltage and the active and reactive powers of the converter stations. Finally, the validity of the proposed control has been verified under various operating conditions by simulation in the MATLAB/Simulink environment.
Single Phase PV Grid-Connected in Smart Household Energy System with Anticipa...IJPEDS-IAES
This paper proposes an algorithm of Smart household energy systems to anticipate fault conditions in power system grid. Single phase PV grid- connected in smart household energy system is a smart system that determines electrical supply conditions to the load in residential electrical system. The smart system is consisted of two voltage source, conventional electricity system from national electricity provider as preferred source and photovoltaic as the alternative source. In smart system, fault conditions can be anticipated by selecting the appropriate voltage sources to supply the load. The condition of smart system can be described in power flow regulation to the load by detection and identification of amplitude, phase angle, and frequency of the voltage source compared to the system reference. The system mechanism is based on detection of voltage source using static transfer switch (STS) with phase locked loop (PLL) as voltage detection algorithm which output is used to determine decision logic algorithm for switching conditions. The results show that conditions of smart power system flow can be obtained based on voltage source selection in decision logic when fault condition occurs.
A novel power converter that can perform both voltage and frequency conversion was proposed. Inappropriate power supply can damage sensitive sub-components and render the connected device inoperable. Henceforth, the proposed voltage–frequency converter acts as an interface to plug any electrical device directly into an electrical socket and provide the voltage and frequency required. The converter used a synchronous reference frame proportional–integral (SRFPI) controller to regulate the instantaneous output voltage and to improve steady state performance. Because the PI controller works together with the synchronous reference frame controller, it is difficult to tune the PI control parameters. To overcome this issue, a new meta heuristic optimization technique called lightening search algorithm (LSA) optimization was used to identify the optimum PI parameter values. A detailed description of the system operation and control strategy was presented. Finally, the performance of the converter was analyzed and verified by simulation and experimental results. The experimental result has shown that the proposed system has satisfactory output voltage and frequency under different input voltages.
This slide presents the control aspects of Energy Storage System in Microgrid. Later I will discuss about the control strategy with integration to DGs and EVs.
Comparative Analysis of Linear Controllers used for Grid Connected PV System IJECEIAES
Requirement for electrical energy is increasing in a ramp function manner. To meet the steady increasing in energy demand it is required to find some alternate source of energy. Except the conventional source of energy one type of renewable energy i.e PV may be regarded as a clean source of energy to meet the energy demand. PV modules generating DC power cannot be directly connected to the electrical infrastructure as most of the grid infrastructure uses either 230volt or 120 volt. Therefore power electronic device most be connected (inverter) between PV and grid. In order to make a competitive market between the renewable generated power and conventional way of generating the power it is required to design a cost effective inverter, qualitative output which is pure sinusoidal and harmonics free. In this paper a comparative analysis among the various linear controllers are presented. Proposed Optimised PID Controller is Presented through MATLAB Simulink based environment.
Two fuzzy logic controllers are proposed in this paper to control a three phase inverter for grid connected photovoltaic system. The first controller was used to predict the DC voltage that allows the three phase inverter to track the maximum power point of photovoltaic array under different environmental conditions such as irradiances and temperature. The second was used to control the active power and reactive power injected into the grid in order to inject the maximum active power produced by photovoltaic systems into grid with high efficiency and low total harmonic distortion using the same three phase inverter. The system components are photovoltaic array, DC link voltage, three-phase inverter, inverter control, LC filter, transformer and grid. To verify the effectivnesse of the introdueced system, modeling and simulation are verified in Matlab/Simulink due to its frequent use and its effectiveness.
Power quality optimization using a novel backstepping control of a three-phas...IJECEIAES
A novel nonlinear backstepping controller based on direct current (DC) link voltage control is proposed in three-phase grid-connected solar photovoltaic (PV) systems to control the active and reactive power flow between the PV system and the grid with improved power quality in terms of pure sinusoidal current injection with lower total harmonic distortion (THD), as well as to ensure unity power factor, or to compensate for reactive power required by the load, i.e., the electrical grid. The output power of the PV array is supplied to the grid through a boost converter with maximum power point tracking (MPPT) control and an inverter. Simulation results of the proposed controller show good robustness under nominal conditions, parameter variations, and load disturbances, which presents the main advantage of this controller as compared to an existing controller. The performance of this work was evaluated using a MATLAB/Simulink environment.
Grid fault Control Scheme for Peak Current Reduction in Photovoltaic Inverte...IJMER
In this paper presents a control scheme for grid interactive photovoltaic inverters to minimize
peak current during unbalanced voltage sag. Power quality of a photovoltaic (PV) inverter deteriorates due
to the presence of grid faults with voltage sag. In grid connected PV important feature is the ride-through
capability, which allows the device to remain connected to the grid during different types of grid
disturbances and avoid the need to disconnect. But during the voltage sag, the source should operate with
increasing converter currents to maintain the injection of the generated power in the system. This abnormal
operation may result in undesired system disconnections due to overcurrent during voltage sag. In this
paper discuss a control scheme provide, controller for a PV three-phase inverter that ensures minimum
peakvalues in the grid- injected currents during voltage sag
Analysis of fuzzy logic controller based bi-directional DC-DC converter for b...IJECEIAES
This paper proposes a fuzzy logic-based battery energy management system in hybrid renewable system. The novel topology consists of solar and wind energy system-based input sources and a battery bank to store the energy when in excess. The PV-Wind source is equipped with unidirectional boost converter whereas, the battery storage system is connected to the system with a bi-directional DC/DC converter. The main novelty of this research is the fuzzy logic-based battery management system which charges and discharges into the DC bus system based on the supply-load demand. The fuzzy logic controller (FLC) based maximum power point tracking (MPPT) is used in the PV and wind energy conversion system (WECS) to track the maximum available power for the different irradiance and wind velocity respectively. The obtained results are compared to conventional P&O MPPT control algorithm to find the effectiveness of the system. A 500 W PV system and a 500 W Permanent magnet synchronous generator (PMSG) based WECS is implemented for its simplicity and high efficiency. The proposed control topology is designed and tested using MATLAB/ Simulink.
Hysteresis-based Voltage and Current Control Techniques for Grid Connected So...IJECEIAES
Solar PV system development and integration with existing grid is very fast in recent years all over the world, as they require limited maintenance, pollution free and simple structure. When observing the factors affecting the performance of the grid connected solar photovoltaic system, the inverter output voltage with harmonics add with the harmonics generated due to the non-linear loads, retain a bigger challenge to maintain power quality in the grid. To maintain grid power quality, better inverter control technique should be developed. This paper presents the two control techniques for grid-tied inverters. This study developed the hysteresis controller for the inverter. Hysteresis controller used in this work two way (i) Voltage control mode (ii) Current control mode. Matlab/Simulink model is developed for the proposed system. Further the study presents the comparative evaluation of the performance of both control techniques based on the percentage of total harmonic distortion (THD) with the limits specified by the standards such as IEEE 1547 and IEC 61727 and IEEE Std 519-2014.
Current Controller Based Power Management Strategy for Interfacing DG Units t...IJECEIAES
This paper proposes a power management strategy of parallel inveters based system, to enhance the power generation capacity of the existing system with distributed energy sources one has to choose DG source based inverter connected in parallel with the existing system.Two DG sources PV, Fuel cells feeds the DC voltage to two parallel inverters connected to the grid. Fixed band hysteresis current control with Instantaneous p-q power theory is adopted to create an artificial environment. Two parallel inverters are able to deliver the harvested power from PV, FC to grid and able to balance the load Without communication between parallel inverters this controller having the capability of load following, the harmonic components of currents at output of inverter are also very low; this will automatically reduces the circulating currents between parallel inverters. Simulation studies are carried out to investigate the results of PV, FC systems connected to the utility grid.
Interleaved Boost Converter (ILBC) is a better converter between Photo Voltaic(PV) source and shunt active power filter. This paper deals with comparison of time domain outputs of PI and Fractional Order PID(FOPID) controlled ILBC fed shunt active filter in a grid connected PV system. The aim of this work is to minimize current ripple using ILBC between PV system and filter to improve the dynamic performance of shunt active filter. Closed loop monitored PI and FOPID systems are modeled, and the corresponding results are presented. MATLAB results of load voltage, current, converter voltage and currents with FOPID exhibits enhanced dynamic response. The proposed FOPID controlled ILBC Fed Shunt Active Filter system (ILBCFSAF) has advantages like low settling time, less peak over shoot and reduced steady state error in load voltage. The simulation results of ILBCSAF are compared with the corresponding hardware results.
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Similar to Adaptive Fuzzy PI Current Control of Grid Interact PV Inverter (20)
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.
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.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
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.
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.
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system line voltage feed forward is used, unwanted compensations increase the Voltage harmonics in the
current waveform in this method. Recently, proportional resonant (PR) controllers [8-10] areused as current
controller to achieve the unity power factor correction rectifiers connected to the grid. The PR controller has
given the infinite gain at resonance frequency and zero steady state error. Whatever it is harmonic
compensation of the PR controller is limited to low order current harmonic frequency is out of the band width
of the system. But it has disadvantage that it needs the resonance frequency information is depending on the
grid frequency in grid connected system which is variable [11].
So the operation of the grid connected inverter with linear control techniques with fixed gain is not
given suitable performance with change in the system parameters. The grid connected inverter not only
operates different circumstances and also meet the international standards [12-14]. Fuzzy logic control (FLC)
is a non-linear which is used to updates the gains of the PI or PID controller has given the better performance
with changing the parameter conditions and load disturbances [15-17]. Thus, FLC is used and given the
better performance to control the plant with dynamic changes and grid interact inverter in variable wind
energy applications and in FLC is used to extract the maximum power from PV panel [18-20].In fuzzy-PI
controllers, fuzzy logic decides the gains of the PI controller according to operation point of the system is
depending on the parameter changes [21-22].Fuzzy PI control makes the system insensitive to external
circumstances changes are there in Renewable energy system like PV and Wind [23]. Since supply
specifications and grid conditions are variable, adaptive control of the grid connected inverters is important to
achieve requirements of the grid as well as consumers [24-25].
This paper is organised as Section 2 Describes the modeling of PV Array, Section 3 Describes the
inverter and design of the LCL filter and Section 4 Presentes the design of the Adaptive Fuzzy PI controller.
In Section 5 the Resultes And Discussion.
2. DESIGN OF THE PV ARRAY
Generally, A PV cell is a simple P-N junction diode which converts solar irradiation into electricity.
PV cell is represented as a combination the current source (Ipv), shunt resistance (Rp), diode and a series
resistance (Rs). In order to overcome the imperfections of PV single diode modeling at high voltages and low
voltages, a two diode model of PV solar cell is considered is shown in the Figure 1 [3].
Figure 1. Two diode model of the PV Cel
The PV cells are connected in series (Ns× Np cells, where Np= 1) to produce the PV module. Basic
equation that describes the current output of PV module using the two- diode model is given by equation.
The PV cell voltage- current relationship in equation (1) is modified for PV module as [4-6].
sh
t
pss
I
Vn
NRIVN
NpIoNpIphI
1
*
/*/
exp (1)
In grid connected PV system, modules are configured in series- parallel structure with any number
of PV modules (Nss ×Npp modules) to produce the PV array. Then the PV module voltage-current relationship
in Equation (1) is modified for PV array and it is given by (2), [5].
r
go
r
rso
TTnk
Eq
T
T
II
11*
exp (2)
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Where Ipv, Io1, Io2, Rs are the parameters of the individual modules, Ns and Np are the number of cells
connected in series and parallel of module respectively, Nss and Npp are the number of modules connected in
series and parallel respectively for array. In this work PV Array is designed using the KC200GT solar module. Its
Parameters are given in the Table 1 [4].
Table 1. KC200GT PV Module Parameter
Parameter Value
Maximum Voltage (Vm) 26.3V
Current at Maximum Power (Im) 7.61A
Open Circuit Voltage (Voc) 32.9V
Short Circuit Current (Isc) 8.21A
Total No.of Cells in Series (Ns 54
Total No.of Cells in Parallel (Np) 1
Temperature Coefficient of Voc(Kv) -123 mV/o
C
Temperature Coefficient of Isc(Ki) 3.18mA/o
C
saturation current Io1 = Io2 1.045×10−9
A
Rp 415.405 Ω.
Rs 0.221 Ω.
3. THE THREE PHASE INVERTER
3-Ph Voltage source inverter connected to grid with LCL filter. Consisting the six switches as
shown in the Figure 2. In this paper these switches are controlled with the help of the Adaptive fuzzy PI
controller. Inverter output voltage is defined in terms of the switching states and input DC voltage. The
magnitude of the output voltage is controlled by means of the modulation index of the PWM and frequency
of the output voltage is equal to the frequency of the reference wave generated by the fuzzy controller.
3-Ø
GridPV
SYSTEM
Figure 2. Three-phase grid connected PV inverter
Then, the output voltage „Vi „can be related to the switching state vector „S „and VPV.
SVV PVi (3)
Where VPV is the PV voltage after MPPT.
The overall block diagram of the system is given in the Figure 3. The fuzzy controller is used to
update the gains of the PI Controller for the Parametric Changes. The PI controller processes the Error in
current and generates the reference Voltage.The reference voltage is input to the PWM operation.Generates
the switcheing signal to the 3-Ph Inverter. In this work frequency modulation index is taken as the 200.The
magnitude of the output voltage is controlled by voltage modulation Index. It is dependeing on the error in
Current.
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3-Ø
INVERTER
3-Ø
Transformer
3-Ø
GRID
3-Ø
PLL
3-Ø
Ref Current
Fuzzy logic
Controller
PI
Controller
d/dt
PWM
GENERATOR
Fuzzy logic
Controller
PI
Controller
d/dt
PV
SYSTEM
Figure 3. Overall Block Diagram of the PV Inverter Connected to the grid with Adaptive Fuzzy PI Controller
Table 2. Parameter of the System
Variable Speed (rpm)
PV Voltage 600 V
Grid Voltage 415V L-L (rms)
Grid Frequency 50Hz
Inverter Side Inductance(Li) 3mH
Grid Side Inductance(Lg) 2.2mH
Filter Capacitor(Cf) 0.015μF
Carrier Frequency 10KHz
4. DESIGN OF THE FUZZY PI CONTROLLER
The Architecture of thefuzzy controller is shown in Figure 4. It has three units Fuzzifier unit,
Interface unit and Defuzzifier at the out terminal. It has input and output variables. Error and change in error
currents are inputs whereas proportional gain (Kp) and Integral gain (KI) are the output variable [19-21]. The
error in current and change in error currents are defined in Equation (4) and Equation (5). Change in error
current means difference between the present error current and previous error current value. Which are
defined in (4) & (5) respectively. In this work input five membership levels are defined as Negative Large
(NL2), Negative Small (NS1), Zero (Z), Positive Small (PS1), Positive Large (PL2) and for output
membership function three levels are defined as Large (L2), Medium (M1), Small (S0) which are used to
build input and output membership functions and Based on the rule matrix‟s table foroutput variable Ki and
Kp are given in Table 3 & Table 4 [23], [24]. The membership fuction of the input and output varibles are
shown in Figure 5 to Figure 8. Three Dimentinal variation of the Fuzzy Inputs (I d&Iq) and outputs KIand Kp
are shown in Figure 9 and Figure 10 [25].
)k(I)k(I)k(ei gr (4)
)1k(ei)K(eiei (5)
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Figure 4. Architecture of the Fuzzy controller
Membership functions for Error Current (Id& Iq)
Figure 5. Membership functions of error in currents
(Id& Iq)
Figure 6. Membership functions of change in error
(Id& Iq)
` ` ` ` `
Figure 7. Membershipfunction of the output (Ki) Figure 8. Membership function of the output (Kp)
Table 3. Rule Matrices table for Kp output Variable
Output
(KP)
Error(e)
Change
In
Error(ce)
NL2 NS1 Z PS1 PL2
NL2 L2 L2 M1 M1 S0
NS1 L2 L2 M1 S0 S0
Z M1 M1 M1 M1 M1
PS1 S0 M1 M1 M1 L2
PL2 S0 S0 M1 L2 L2
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Table 4. Rule Matrices table for Ki output Variable
Output
(Ki)
Error(e)
Change
In
Error(ce)
NL2 NS1 Z PS1 PL2
NL2 S0 S0 M1 L2 L2
NS1 S0 S0 M1 L2 L2
Z M1 M1 M1 M1 M1
PS1 L2 L2 M1 S0 S0
PL2 L2 L2 M1 S0 S0
Figure 9. Three dimensional variation of the Fuzzy
inputs and output Kp
Figure 10. Three dimensional variation of the Fuzzy
inputs and output KI
Three Dimensional variation of the Fuzzy inputs (Id & Iq) and outputs KI and Kp are shown in
Figure 9 and Figure 10.
The Kp and Ki taken from fuzzy logic controller is given to PI controller. The schematic diagram of
PI controller is shown in Figure 11. The Kp and Ki values multiplied with error and are sent to zero order hold
and discrete time integrator.
Figure 11. Schematic Diagram of PI Controller
5. SIMULATION RESULTS
5.1. Case Study 1: Change in Reference Current
The above mentioned system parameters in Table 4 are considered to study the adaptive fuzzy
current controller makes the inverter to tracks the change in reference current at fixed DC input voltage. Here
temperature and irradiation in the nature is considered as constant to get the constant DC Voltage to the
inverter as shown in Figure 12. Here changes in reference current is considered at 0.5 sec from 4A to 6A as
shown in Figure 17 causes to change the PV current supllied to the Inverter as shown in Figure 13. Inverter
output voltage is shown in Figure 14. The variation of the Kp and Ki values due to change in reference current
are shown in Figure 15 and Figure 16. Grid current followes the reference current with less transient behavier
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and zero steady state error even though change in reference Current as shown in Figure 18. Total Harmonic
Distortion of the Grid current is less the 5% as shown in the Figure 19.
Figure 12. PV Output Voltage Figure13. PV Current
Figure14. Inverter Output Voltage Figure 15. Variation of the Proportional Gain (Kp)
Figure 16. Variation of the Integral Gain ( Ki) Figure 17. Referance Current
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Figure 18. Referance Current & Grid Current Figure 19. THD analysis of the Grid Current
5.2. Case Study 2: Change in DC Voltage
Same system parameters are considered to study weather adaptive fuzzy current controller makes
the inverter to track the reference current if there is change in DC input voltage. Here change in irradiation is
considered to change the DC Voltage from 0.5 Seconds and PV Currents are shown in Figure 20 and
Figure 21 respectively. The constant grid current is considered as 5A shown in Figure 25. The variation of
the Kp and Ki values which are updated by fuzzy controller due to change in DC input voltage as shown in
Figure 23 and Figure 24. Total Harmonic Distortion of the Grid current is less the 5% as shown in the
Figure 27.
Figure 20. Change in PV Voltage Figure 21. PV Current
Figure 22. Inverter Output Voltage Figure 23. Variation of the Integral Gain ( Ki)
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Figure 24. Variation of the Proportional Gain (Kp) Figure 25. Grid Current
Figure 26. Referance Current & Grid Current Figure 27. THD Analysis of the Grid Current
The THD values of the Grid Currents with PI Controller, Fuzzy controller and Fuzzy PI current
controllers are given in the Table 5. Adaptive Fuzzy Controller improved the quality of the grid current.
Table 5. Comparision of the Controllers
Currents With PI THD% With FLC THD% With Fuzzy-PI THD%
4A 4.81 5.28 4.71
5A 4.01 4.27 3.54
6A 3.59 4.66 2.98
7A 4..80 4.79 2.57
8A 5.80 7.58 2.42
9A 5.50 6.63 2.16
6. CONCLUSION
In this work adaptive Fuzzy PI current controller is implemented for the grid connected 3ph PV
inverter under different parametric conditions. When there is change in PV voltage and reference current.
The Fuzzy controller updates the gains of the PI controller so that grid current traces the references Current
with less transient behavior, zero steady state error and low THD value of the Grid current compared to the
PI Controller, Fuzzy controller. It is implemented and verified in Matlab-Simulink.
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BIOGRAPHIES OF AUTHORS
R.S. Ravi Sankar obtained A.M.I. E degree from institute of engineers(India) in 2002.he obtained
M.Tech. from JNTUH Hyderabad in 2004.currently doing Ph.D. in JNTUA anthapuram. He got 10
years of the teaching experience. his area of interest is control of Voltage source inverter
connected to grid and application of power electronics to the power system and renewable energy
systems and presently working as associate professor of Electrical Engineering in VIIT
Vishakhapatnam.
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S.V. Jayaram Kumar obtained B.E and M.E degrees from Andhra university Visakhapatnam in
1976 and 1979. He obtained Ph. D degree from Indian Institute of technology Kanpur in the year
2000. He has got 35 years of teaching experience. His areas of interest are Flexible AC
Transmission systems, and application of power electronics to power systems. He worked in
JNTUH college of Engineering Hyderabad till 2014 and presently working as professor of
Electrical Engineering in GRIET Hyderabad
Gorapalli Mohan Rao currently is an assistant professor in the Vignan‟s institute of Information
Technology, JNTUK Kakinada, India. He received his M.Tech. Degree from the Department of
Electricals and Electronics Engineering, with the Best Dissertation Award. He received his B.Tech
from Visakha institute of engineering Technology. His research work has been focused on PV
system, MPPT, Fuzzy Systems, Grid Interactive Inverters, and Controllers.