In modern world,our entire life moves around Computers. Most of our tasks are dependent on the Computers,like Communication,Ticket Reservations,Researches,Printing,and Education etc. When we communicate with each other by using Computers through E Mails,a number of Computers are used for this purpose and the collection of these computers forms a network,which is called a Computer Network. As more and more peoples are going to be connected through the general network (INTERNET),the problem of security arises. Now a day,a number of security issues occur in networks which include Sniffing,Spoofing,Security Attacks,Malwares,Unauthorized Access,etc. This will create havoc for the users,who wants to communicate with each other through these networks. So,to make the communication between two users via the Computer Networks,we have to follow some security measures,which include using the Firewalls,Anti Malicious Software,Intrusion Detection Systems,Cryptography Techniques,et c. This paper is basically focused on how the communication between two users has been performed by using Computer Networks and how to make such a communication
A NOVEL CONTROL STRATEGY FOR POWER QUALITY IMPROVEMENT USING ANN TECHNIQUE FO...IJERD Editor
The proposed system presents power-control strategies of a Micro grid-connected hybrid generation
system with versatile power transfer. This hybrid system allows maximum utilization of freely available
renewable energy sources like wind and photovoltaic energies. For this, an adaptive MPPT algorithm along with
standard perturbs and observes method will be used for the system.
The inverter converts the DC output from non-conventional energy into useful AC power for the
connected load. This hybrid system operates under normal conditions which include normal room temperature
in the case of solar energy and normal wind speed at plain area in the case of wind energy. However, designing
an optimal micro grid is not an easy task, due to the fact that primary energy carriers are changeable and
uncontrollable, as is the demand. Traditional design and optimization tools, developed for controlled power
sources, cannot be employed here. Simulation methods seem to be the best solution.
The dynamic model of the proposed system is first elaborated in the stationary reference frame and
then transformed into the synchronous orthogonal reference frame. The transformed variables are used in
control of the voltage source converter as the heart of the interfacing system between DG resources and utility
grid. By setting an appropriate compensation current references from the sensed load currents in control circuit
loop of DG, the active, reactive, and harmonic load current components will be compensated with fast dynamic
response, thereby achieving sinusoidal grid currents in phase with load voltages, while required power of the
load is more than the maximum injected power of the DG to the grid. In addition, the proposed control method
of this paper does not need a phase-locked loop in control circuit and has fast dynamic response in providing
active and reactive power components of the grid-connected loads.
Defining Control Strategies for Micro Grids Islanded Operation with Maximum P...IAES-IJPEDS
This paper explains about an intelligent control method for the maximum
power point tracking (MPPT) of a photo voltaic system with different
temperature and insolation conditions. This method uses a fuzzy logic
controller applied to a DC-DC converter. The different steps of the design of
this controller are presented together with its simulation and the feasibility of
control methods to be adopted for the operation of a micro grid when it
becomes isolated. Normally, the micro grid operates in interconnected mode
with the medium voltage network; however, scheduled or forced isolation
can take place. In such conditions, the micro grid must have the ability to
operate stably and autonomously. An evaluation of the need of storage
devices and load to take off strategies is included in this paper. The MPPT of
a photovoltaic system for Micro Grid operaion using a Fuzzy logic control
scheme is successfully designed and simulated by using MATLAB/Simulink
Software.
This paper discusses about a LabVIEW based controller for the hybrid renewable energy system operated AC-DC microgrid with the major objectives of: i) predicting the power generation potential of the solar–PV and wind generators ii) effective power management iii) load scheduling based on the available power with the renewable sources and iv) grid/islanding mode of operation of the microgrid. In order topredict the output power of wind generator and Solar-PV system, an artificial neural network is developed.The laboratory-scale model of three phase, 400 V, 10 kVA microgrid structure is developed at National Institute of Technology Calicut, India. The developed LabVIEW based controller has been tested successfully for a real-time load and source in the laboratory environment. Test results show that the designed controller is effectively managing the output powerof the primary energy sources under different scenarios.
A Hybrid Control Scheme for Fault Ride-Through Capability using Line-Side Con...Suganthi Thangaraj
As the wind power installations are increasing in number, Wind Turbine Generators (WTG) are required to have Fault Ride-Through (FRT) capabilities. Lately developed grid operating codes demand the WTGs to stay connected during fault conditions, supporting the grid to recover faster back to its normal state. In this paper, the generator side converter incorporates the maximum power point tracking algorithm to extract maximum energy from wind turbine system. A hybrid control scheme for energy storage systems (ESS) and braking choppers for fault ride-through capability and a suppression of the output power fluctuation is proposed for permanent-magnet synchronous generator (PMSG) wind turbine systems. During grid faults, the dc-link voltage is controlled by the ESS instead of the line-side converter (LSC), whereas the LSC is exploited as a STATCOM to inject reactive current into the grid for assisting in the grid voltage recovery. A simple model of the proposed system is developed and simulated in MATLAB environment. The effectiveness of the system is validated through extensive simulation results
GA Based Controller for Autonomous Wind-DG Micro gridIOSRJEEE
A single renewable source of energy when integrated with other sources of energy it is termed as hybrid system. In this paper an active power control strategy has been developed such that when the wind alone is not able to meet the energy demand, without compromising the frequency a transition occurs to wind diesel mode so that the energy demand is met. This work proposes the coordination of WDG(Wind DG), VSC’s are used for two purposes one is frequency control and another is voltage control. PMBLDC generator is used as a wind power generator and the Incremental conductance method is used as MPPT along with boost converter. This output is stored into battery system (BS) and surplus is supplied to the consumer loads. Back propagation feed forward (BPFF) control scheme is used for VF control of VSC. This controller provides harmonics elimination, load leveling and reactive power compensation and also regulates the voltage at PCC. Genetic algorithm is used for the purpose of tuning PI controller of BPFF. The performance and the analysis is done in a user friendly MATLAB/Simulink environment.
A NOVEL CONTROL STRATEGY FOR POWER QUALITY IMPROVEMENT USING ANN TECHNIQUE FO...IJERD Editor
The proposed system presents power-control strategies of a Micro grid-connected hybrid generation
system with versatile power transfer. This hybrid system allows maximum utilization of freely available
renewable energy sources like wind and photovoltaic energies. For this, an adaptive MPPT algorithm along with
standard perturbs and observes method will be used for the system.
The inverter converts the DC output from non-conventional energy into useful AC power for the
connected load. This hybrid system operates under normal conditions which include normal room temperature
in the case of solar energy and normal wind speed at plain area in the case of wind energy. However, designing
an optimal micro grid is not an easy task, due to the fact that primary energy carriers are changeable and
uncontrollable, as is the demand. Traditional design and optimization tools, developed for controlled power
sources, cannot be employed here. Simulation methods seem to be the best solution.
The dynamic model of the proposed system is first elaborated in the stationary reference frame and
then transformed into the synchronous orthogonal reference frame. The transformed variables are used in
control of the voltage source converter as the heart of the interfacing system between DG resources and utility
grid. By setting an appropriate compensation current references from the sensed load currents in control circuit
loop of DG, the active, reactive, and harmonic load current components will be compensated with fast dynamic
response, thereby achieving sinusoidal grid currents in phase with load voltages, while required power of the
load is more than the maximum injected power of the DG to the grid. In addition, the proposed control method
of this paper does not need a phase-locked loop in control circuit and has fast dynamic response in providing
active and reactive power components of the grid-connected loads.
Defining Control Strategies for Micro Grids Islanded Operation with Maximum P...IAES-IJPEDS
This paper explains about an intelligent control method for the maximum
power point tracking (MPPT) of a photo voltaic system with different
temperature and insolation conditions. This method uses a fuzzy logic
controller applied to a DC-DC converter. The different steps of the design of
this controller are presented together with its simulation and the feasibility of
control methods to be adopted for the operation of a micro grid when it
becomes isolated. Normally, the micro grid operates in interconnected mode
with the medium voltage network; however, scheduled or forced isolation
can take place. In such conditions, the micro grid must have the ability to
operate stably and autonomously. An evaluation of the need of storage
devices and load to take off strategies is included in this paper. The MPPT of
a photovoltaic system for Micro Grid operaion using a Fuzzy logic control
scheme is successfully designed and simulated by using MATLAB/Simulink
Software.
This paper discusses about a LabVIEW based controller for the hybrid renewable energy system operated AC-DC microgrid with the major objectives of: i) predicting the power generation potential of the solar–PV and wind generators ii) effective power management iii) load scheduling based on the available power with the renewable sources and iv) grid/islanding mode of operation of the microgrid. In order topredict the output power of wind generator and Solar-PV system, an artificial neural network is developed.The laboratory-scale model of three phase, 400 V, 10 kVA microgrid structure is developed at National Institute of Technology Calicut, India. The developed LabVIEW based controller has been tested successfully for a real-time load and source in the laboratory environment. Test results show that the designed controller is effectively managing the output powerof the primary energy sources under different scenarios.
A Hybrid Control Scheme for Fault Ride-Through Capability using Line-Side Con...Suganthi Thangaraj
As the wind power installations are increasing in number, Wind Turbine Generators (WTG) are required to have Fault Ride-Through (FRT) capabilities. Lately developed grid operating codes demand the WTGs to stay connected during fault conditions, supporting the grid to recover faster back to its normal state. In this paper, the generator side converter incorporates the maximum power point tracking algorithm to extract maximum energy from wind turbine system. A hybrid control scheme for energy storage systems (ESS) and braking choppers for fault ride-through capability and a suppression of the output power fluctuation is proposed for permanent-magnet synchronous generator (PMSG) wind turbine systems. During grid faults, the dc-link voltage is controlled by the ESS instead of the line-side converter (LSC), whereas the LSC is exploited as a STATCOM to inject reactive current into the grid for assisting in the grid voltage recovery. A simple model of the proposed system is developed and simulated in MATLAB environment. The effectiveness of the system is validated through extensive simulation results
GA Based Controller for Autonomous Wind-DG Micro gridIOSRJEEE
A single renewable source of energy when integrated with other sources of energy it is termed as hybrid system. In this paper an active power control strategy has been developed such that when the wind alone is not able to meet the energy demand, without compromising the frequency a transition occurs to wind diesel mode so that the energy demand is met. This work proposes the coordination of WDG(Wind DG), VSC’s are used for two purposes one is frequency control and another is voltage control. PMBLDC generator is used as a wind power generator and the Incremental conductance method is used as MPPT along with boost converter. This output is stored into battery system (BS) and surplus is supplied to the consumer loads. Back propagation feed forward (BPFF) control scheme is used for VF control of VSC. This controller provides harmonics elimination, load leveling and reactive power compensation and also regulates the voltage at PCC. Genetic algorithm is used for the purpose of tuning PI controller of BPFF. The performance and the analysis is done in a user friendly MATLAB/Simulink environment.
In a distributed generation system, divers renewable agents are connected to the low voltage 3 phase utility grid by an inverter which is used as power condition and must assurance the higher efficiency of the renewable agent. To achieve this level of efficiency, a unitary power factor between the utility grid voltages and the inverter currents is necessary, and a synchronization algorithm is required for the perfect synchronization between the 3-phase utility grid and the renewable agent. The aim of this paper is to present the optimization of the performance of a Synchronization controller for a 3-phase photovoltaic grid-connected system, assessing its accuracy under different conditions and studying their drawbacks and advantages. A grid connected photovoltaic system with a nominal power of 5 kW is used so as to assess the behavior of the synchronization algorithm when the 3 phase utility grid is affected by some disturbances such as voltage unbalances.
Optimized Power Flows in Microgrid with and without Distributed Energy Storag...Power System Operation
This study presents a combined algebraic and power flow model of a microgrid. The aim of this study is to introduce a strong tool which is capable to compare physical parameters of a microgrid which are hardly possible to calculate only by common algebraic optimization methods. Especially interesting is comparison between microgrids without energy storage, with a single bigger battery plant and with distributed batteries. This study focuses mainly on high voltage (HV) part of a transformer, inductive power and power losses in microgrids. Modelled microgrid consists of five robust nodes (which can represent living quarters with renewable energy production and energy storage) connected into a single transformer node, which later leads to the transmission system.
Pantech modern power system projects [simulink & m-file] 2016-17Senthil Kumar
Pantech provides power electronics projects using matlab and hardware design. We can support on all type of inverter, converter, Renewable sources both in simulation and hardware.We can support on PIC Controllers, dSPIC Controllers, DSP Processor and FPGA Processor. www.pantechproed.com
Power quality improvement based on hybrid coordinated design of renewable ene...IJECEIAES
This paper presents a comprehensive analysis of power quality for static synchronous compensator on the distribution power system (DSTATCOM) when different types of energy sources are used to supply the DC link channel of DSTATCOM. These types of power supplies have a different effect on the compensation of DSTATCOM due to operation nature of these sources. The dynamic response of the DSTATCOM has investigated that produced by individual and hybrid energy sources to evaluate the influence of these sources in terms of time response, compensation process and reduce the harmonics of current source. Three cases have been considered in this study. First the photovoltaic (PV) cells alone, second the battery storage alone, and third a hybrid coordinated design between (PV cells with battery storage) is used. A boost DC-DC circuit has connected to a photovoltaic cell with maximum power point tracking (MPPT) while DC-DC buck-boost circuit is used with a battery. High coordination between PV and battery circuits in the hybrid system is used to improve the performance. A synchronous reference frame (SRF) with a unit vector has used to control the DSTATCOM. The simulation results show that the hybrid design has a superiority response compared to the individual sources.
ENERGY MANAGEMENT SYSTEM FOR CRITICAL LOADS USING POWER ELECTRONICSrenukasningadally
The work aims at an Energy Management System (EMS) for Critical loads using Power Electronics. Here hybrid power sources (Grid and Solar cells) with battery have been used to supply the power to the critical loads at all times, suppose an end user increases his critical loads or non-critical loads this EMS system helps to maintain continuous power supply to these loads. Solar or Photovoltaic cells have been used for storing energy through battery and these batteries will discharge the stored energy at two conditions, one is when grid is shut down for short duration or for a long duration and another one is when there sudden increase in load by users
Energy Management of Distributed Generation Inverters using MPC Controller i...IJMER
This paper presents a microgrid consisting of different distributed generation (DG) units
that are connected to the distribution grid. An energy-management algorithm is implemented to
coordinate the operations of the different DG units in the microgrid for grid-connected and islanded
operations. The proposed microgrid consists of a photovoltaic (PV) array which functions as the
primary generation unit of the microgrid and a proton-exchange membrane fuel cell to supplement the
variability in the power generated by the PV array. A lithium-ion storage battery is incorporated into
the microgrid to mitigate peak demands during grid-connected operation and to compensate for any
shortage in the generated power during islanded operation. The control design for the DG inverters
employs a new model predictive control algorithm which enables faster computational time for large
power systems by optimizing the steady-state and the transient control problems separately. The design
concept is verified through various test scenarios to demonstrate the operational capability of the
proposed microgrid, and the obtained results are discussed.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Operation and Control of Grid Connected Hybrid AC/DC Microgrid using Various RESIAES-IJPEDS
This paper proposes a Hybrid AC/DC Microgrid in alliance with Photo Voltaic (PV) energy, Wind Energy and Proton Exchange Membrane (PEM) Fuel cells. Microgrids are becoming increasingly attractive to the researchers because of the less greenhouse gases, low running cost, and flexibility to operate in connection with utility grid. The Hybrid AC/DC Microgrid constitutes independent AC and DC subgrids, where all the corresponding sources and loads are connected to their respective buses and these buses are interfaced using an interfacing converter. The Hybrid AC/DC Microgrid increases system efficiency by reducing the multiple reverse conversions involved in conventional RES integration to grid. A Small Hybrid AC/DC Microgrid in grid connected mode was modeled and simulated in MATLAB- SIMULINK environment. The simulation results prove the stable operation considering the uncertainty of generations and loads.
Adaptive Control Scheme for PV Based Induction MachineIJMTST Journal
An adaptive control scheme for maximum power point tracking of a single-phase grid-connected photovoltaic system is presented. The difficulty on design a controller that may operate a photovoltaic system on its maximum power point (MPP) is that, this MPP depends on temperature and solar irradiance, ambient conditions that are time-varying and difficult to measure. A solution using an on-line sliding mode estimator is presented. It estimates three different parameters that depend on solar irradiance and temperature, eliminating the necessity of having any sensor for these environmental variables. It is capable of estimate time-varying parameters. A complete analysis was done taking into account the non-linearity’s showed by the closed-loop system. An adaptive law was found to substitute a perturbation bound and also to eliminate possible chattering due to the discontinuous controller term. Computer simulations are presented to show the good performance of the controller. The controller detects the deviation of the actual trajectory from the reference trajectory and corresponding changes the switching strategy to restore the tracking. Prominent characteristics such as invariance, robustness, order reduction, and control chattering are discussed in detail. Methods for coping with chattering are presented. Both linear and nonlinear systems are considered The proposed concept can be implemented to adaptive control scheme for induction machine using Matlab/Simulink software.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Performance analysis of grid-tied photovoltaic system under varying weather c...IJECEIAES
Model and simulation of the impact of the distribution grid-tied photovoltaic (PV) system feeding a variable load with its control system have been investigated in this study. Incremental Conductance (IncCond) algorithm based on maximum power point tracking (MPPT) was implemented for the PV system to extract maximum power under different weather conditions when solar irradiation varies between 250 W/m 2 and 1000 W/m 2 . The proposed system is modelled and simulated with MATLAB/Simulink tools. Under different weather conditions, the dynamic performance of the PV system is evaluated. The results obtained show the efficacy of the proposed MPPT method in response to rapid daytime weather variations. The results also show that the surplus power generated is injected into the grid when the injected power from the PV system is higher than the load demand; otherwise, the grid supplies the load.
A Review on Power Quality Issues and their Mitigation Techniques in Microgrid...ijtsrd
Power Quality is playing an increasingly significant role both at supply and demand sides. With the advent of participation of private players in distribution systems, the power quality is expected to be the pivotal decisive factor before the consumers. Due to ever growing application of switching devices, the power quality is bound to get deteriorated, at the same time such devices are also prone to malfunction due to poor power quality. The world is driven by the carbon emission to replace the conventional generation by as much renewable generation as possible. The above situation has attracted the attention of researchers to identify and suggest the mitigation techniques of power quality issue’s for improving the performance of microgrid containing renewable energy resources. An attempt has been made to comprehensively present a review of the research carried out thusfar. Anita Chaudhery | Pramod Kumar Rathore "A Review on Power Quality Issues and their Mitigation Techniques in Microgrid System" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-2 , February 2022, URL: https://www.ijtsrd.com/papers/ijtsrd49299.pdf Paper URL: https://www.ijtsrd.com/engineering/electrical-engineering/49299/a-review-on-power-quality-issues-and-their-mitigation-techniques-in-microgrid-system/anita-chaudhery
In a distributed generation system, divers renewable agents are connected to the low voltage 3 phase utility grid by an inverter which is used as power condition and must assurance the higher efficiency of the renewable agent. To achieve this level of efficiency, a unitary power factor between the utility grid voltages and the inverter currents is necessary, and a synchronization algorithm is required for the perfect synchronization between the 3-phase utility grid and the renewable agent. The aim of this paper is to present the optimization of the performance of a Synchronization controller for a 3-phase photovoltaic grid-connected system, assessing its accuracy under different conditions and studying their drawbacks and advantages. A grid connected photovoltaic system with a nominal power of 5 kW is used so as to assess the behavior of the synchronization algorithm when the 3 phase utility grid is affected by some disturbances such as voltage unbalances.
Optimized Power Flows in Microgrid with and without Distributed Energy Storag...Power System Operation
This study presents a combined algebraic and power flow model of a microgrid. The aim of this study is to introduce a strong tool which is capable to compare physical parameters of a microgrid which are hardly possible to calculate only by common algebraic optimization methods. Especially interesting is comparison between microgrids without energy storage, with a single bigger battery plant and with distributed batteries. This study focuses mainly on high voltage (HV) part of a transformer, inductive power and power losses in microgrids. Modelled microgrid consists of five robust nodes (which can represent living quarters with renewable energy production and energy storage) connected into a single transformer node, which later leads to the transmission system.
Pantech modern power system projects [simulink & m-file] 2016-17Senthil Kumar
Pantech provides power electronics projects using matlab and hardware design. We can support on all type of inverter, converter, Renewable sources both in simulation and hardware.We can support on PIC Controllers, dSPIC Controllers, DSP Processor and FPGA Processor. www.pantechproed.com
Power quality improvement based on hybrid coordinated design of renewable ene...IJECEIAES
This paper presents a comprehensive analysis of power quality for static synchronous compensator on the distribution power system (DSTATCOM) when different types of energy sources are used to supply the DC link channel of DSTATCOM. These types of power supplies have a different effect on the compensation of DSTATCOM due to operation nature of these sources. The dynamic response of the DSTATCOM has investigated that produced by individual and hybrid energy sources to evaluate the influence of these sources in terms of time response, compensation process and reduce the harmonics of current source. Three cases have been considered in this study. First the photovoltaic (PV) cells alone, second the battery storage alone, and third a hybrid coordinated design between (PV cells with battery storage) is used. A boost DC-DC circuit has connected to a photovoltaic cell with maximum power point tracking (MPPT) while DC-DC buck-boost circuit is used with a battery. High coordination between PV and battery circuits in the hybrid system is used to improve the performance. A synchronous reference frame (SRF) with a unit vector has used to control the DSTATCOM. The simulation results show that the hybrid design has a superiority response compared to the individual sources.
ENERGY MANAGEMENT SYSTEM FOR CRITICAL LOADS USING POWER ELECTRONICSrenukasningadally
The work aims at an Energy Management System (EMS) for Critical loads using Power Electronics. Here hybrid power sources (Grid and Solar cells) with battery have been used to supply the power to the critical loads at all times, suppose an end user increases his critical loads or non-critical loads this EMS system helps to maintain continuous power supply to these loads. Solar or Photovoltaic cells have been used for storing energy through battery and these batteries will discharge the stored energy at two conditions, one is when grid is shut down for short duration or for a long duration and another one is when there sudden increase in load by users
Energy Management of Distributed Generation Inverters using MPC Controller i...IJMER
This paper presents a microgrid consisting of different distributed generation (DG) units
that are connected to the distribution grid. An energy-management algorithm is implemented to
coordinate the operations of the different DG units in the microgrid for grid-connected and islanded
operations. The proposed microgrid consists of a photovoltaic (PV) array which functions as the
primary generation unit of the microgrid and a proton-exchange membrane fuel cell to supplement the
variability in the power generated by the PV array. A lithium-ion storage battery is incorporated into
the microgrid to mitigate peak demands during grid-connected operation and to compensate for any
shortage in the generated power during islanded operation. The control design for the DG inverters
employs a new model predictive control algorithm which enables faster computational time for large
power systems by optimizing the steady-state and the transient control problems separately. The design
concept is verified through various test scenarios to demonstrate the operational capability of the
proposed microgrid, and the obtained results are discussed.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Operation and Control of Grid Connected Hybrid AC/DC Microgrid using Various RESIAES-IJPEDS
This paper proposes a Hybrid AC/DC Microgrid in alliance with Photo Voltaic (PV) energy, Wind Energy and Proton Exchange Membrane (PEM) Fuel cells. Microgrids are becoming increasingly attractive to the researchers because of the less greenhouse gases, low running cost, and flexibility to operate in connection with utility grid. The Hybrid AC/DC Microgrid constitutes independent AC and DC subgrids, where all the corresponding sources and loads are connected to their respective buses and these buses are interfaced using an interfacing converter. The Hybrid AC/DC Microgrid increases system efficiency by reducing the multiple reverse conversions involved in conventional RES integration to grid. A Small Hybrid AC/DC Microgrid in grid connected mode was modeled and simulated in MATLAB- SIMULINK environment. The simulation results prove the stable operation considering the uncertainty of generations and loads.
Adaptive Control Scheme for PV Based Induction MachineIJMTST Journal
An adaptive control scheme for maximum power point tracking of a single-phase grid-connected photovoltaic system is presented. The difficulty on design a controller that may operate a photovoltaic system on its maximum power point (MPP) is that, this MPP depends on temperature and solar irradiance, ambient conditions that are time-varying and difficult to measure. A solution using an on-line sliding mode estimator is presented. It estimates three different parameters that depend on solar irradiance and temperature, eliminating the necessity of having any sensor for these environmental variables. It is capable of estimate time-varying parameters. A complete analysis was done taking into account the non-linearity’s showed by the closed-loop system. An adaptive law was found to substitute a perturbation bound and also to eliminate possible chattering due to the discontinuous controller term. Computer simulations are presented to show the good performance of the controller. The controller detects the deviation of the actual trajectory from the reference trajectory and corresponding changes the switching strategy to restore the tracking. Prominent characteristics such as invariance, robustness, order reduction, and control chattering are discussed in detail. Methods for coping with chattering are presented. Both linear and nonlinear systems are considered The proposed concept can be implemented to adaptive control scheme for induction machine using Matlab/Simulink software.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Performance analysis of grid-tied photovoltaic system under varying weather c...IJECEIAES
Model and simulation of the impact of the distribution grid-tied photovoltaic (PV) system feeding a variable load with its control system have been investigated in this study. Incremental Conductance (IncCond) algorithm based on maximum power point tracking (MPPT) was implemented for the PV system to extract maximum power under different weather conditions when solar irradiation varies between 250 W/m 2 and 1000 W/m 2 . The proposed system is modelled and simulated with MATLAB/Simulink tools. Under different weather conditions, the dynamic performance of the PV system is evaluated. The results obtained show the efficacy of the proposed MPPT method in response to rapid daytime weather variations. The results also show that the surplus power generated is injected into the grid when the injected power from the PV system is higher than the load demand; otherwise, the grid supplies the load.
A Review on Power Quality Issues and their Mitigation Techniques in Microgrid...ijtsrd
Power Quality is playing an increasingly significant role both at supply and demand sides. With the advent of participation of private players in distribution systems, the power quality is expected to be the pivotal decisive factor before the consumers. Due to ever growing application of switching devices, the power quality is bound to get deteriorated, at the same time such devices are also prone to malfunction due to poor power quality. The world is driven by the carbon emission to replace the conventional generation by as much renewable generation as possible. The above situation has attracted the attention of researchers to identify and suggest the mitigation techniques of power quality issue’s for improving the performance of microgrid containing renewable energy resources. An attempt has been made to comprehensively present a review of the research carried out thusfar. Anita Chaudhery | Pramod Kumar Rathore "A Review on Power Quality Issues and their Mitigation Techniques in Microgrid System" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-2 , February 2022, URL: https://www.ijtsrd.com/papers/ijtsrd49299.pdf Paper URL: https://www.ijtsrd.com/engineering/electrical-engineering/49299/a-review-on-power-quality-issues-and-their-mitigation-techniques-in-microgrid-system/anita-chaudhery
The decline of competence effectuated by the unreplenishable energy etymology due to the plummet of fossil fuels has created an alternate need for renewable energy sources to play a vital role in providing power at a larger scale. Thus, a new system of distribution of energy resources is introduced to tackle the ever-growing demand for power and safety of the environment using renewable energy sources with the traditional ways of transmitting power. Such challenges can be overcome by using hybrid microgrids which helps in detecting and hegemonizing faults more dexterously sanctioning sharing of load and instinctive switching through various algorithms thus improving the system accuracy and adaptability. This exertion incorporates the modeling of an AC hybrid microgrid system analyzed in the is-landed mode. Fuel stack and the photo-voltaic cell are used as renewable energy power sources. It also includes the PID control method to the solution the most encountered problems in a microgrid. The engaged control modus operandi can modulate and regulate the output voltage at an expected and paradigm value. The whole AC hybrid microgrid and its control are simulated in MATLAB/simulink R2020b.
A review of optimal operation of microgrids IJECEIAES
The term microgrid refers to small-scale power grid that can operate autonomously or in concurrence with the area’s main electrical grid. The intermittent characteristic of DGs which defies the power quality and voltage manifests the requirement for new planning and operation approaches for microgrids. Consequently, conventional optimization methods in new power systems have been critically biased all through the previous decade. One of the main technological and inexpensive tools in this regard is the optimal generation scheduling of microgrid. As a primary optimization tool in the planning and operation fields, optimal operation has an undeniable part in the power system. This paper reviews and evaluates the optimal operation approaches mostly related to microgrids. In this work, the foremost optimal generation scheduling approaches are compared in terms of their objective functions, techniques and constraints. To conclude, a few fundamental challenges occurring from the latest optimal generation scheduling techniques in microgrids are addressed.
A survey on power management strategies of hybrid energy systems in microgrid IJECEIAES
The power generation through renewable energy resources is increasing vastly, Solar energy and Wind Energy are the most abundantly available renewable energy resources. The growth of small scale distributed grid networks increasing rapidly in the modern power systems and Distributed Generation (DG) plays a predominant role. Microgrid is one among the emerging techniques in power systems. Power Management is mainly required to have control over the real and reactive power of individual DG and for smooth operation, maintaining stability and reliability. This paper presents a survey of the research works already reported focusing on power management of hybrid energy systems such as mainly solar and wind systems in microgrid. Six different approaches have been studied in detail for AC, DC and hybrid AC/DC microgrid.
In this paper, using a neural controller and a genetic optimization algorithm to control the voltage as well as, control the frequency of the grid along with the management of the reactive power of the micro-grid to control the output power during islanding using Simultaneous bilateral power converters with voltage/frequency droop strategy and optimization of PI coefficients of parallel power converters by genetic-neural micro-grid algorithm to suppress AC side-current flow that increases stability and improvement of conditions frequency and voltage are discussed. Given the performance of the micro-grid in two simulation scenarios, namely transition from on-grid to off-grid, the occurrence of a step change in load in island mode as well as return to working mode is connected. The ability to detect the robust performance and proper performance of two-level neural controller. The controller performance time was also very good, indicating the appropriate features of the method used to design the controller, namely two-level neural, genetics. The main advantage of this method is its simplicity of design. The method used is also efficient and resistant to changes in the system, which results from the simulations.
Reactive Power Sharing Droop Control Strategy for DG Units in an Islanded Mic...IJMTST Journal
The proposed method mainly includes two important operations: error reduction operation and voltage
recovery operation. The sharing accuracy is improved by the sharing error reduction operation, which is
activated by the low-bandwidth synchronization signals. However, the error reduction operation will result in
a decrease in output voltage amplitude. Therefore, the voltage recovery operation is proposed to compensate
the decrease., due to increasing the demand of electricity as well as rapid depletion of fossil fuels, and the
government policies on reduction of greenhouse gas emissions , renewable energy technologies are more
attractive and various types of distributed generation sources, such as wind turbine generators and solar
photo voltaic panels are being connected to low-voltage distribution networks. Micro grid is an integrated
system that contain in s distributed generation sources, control systems, load management, energy storage
and communication infrastructure capability to work in both grid connected and island mode to optimize
energy usage. The paper presents a advanced control technique for a micro grid system which works
efficiently under a decentralized control system.
Intelligent Power Management of Islanded DC Microgrid based on Droop Fuzzy Co...AI Publications
This paper presents a new intelligent control strategy for DC microgrid in islanded operation mode based on droop control method. The DC microgrid under study included a Wind Turbine Generator (WTG), photovoltaic (PV), battery energy storage system (BESS) and a linear resistive load. According to the proposed method, each of distributed generation (DG) sources and BESS can be deployed independently within any controlled microgrid through the fuzzy control strategy. Proposed fuzzy control regulated virtual resistance of DGs and BESS unit locally and real-time based on the available power of DGs and the battery state of charge (SOC), to coordinate the module performances independently and establish the power balance and regulating DC bus voltage. Proposed control strategy for BESS enables the microgrid to supply independently the power required for the load demand when the DGs are not capable of supplying the required power to the load. The proposed fuzzy control strategy was applied locally and without dependency on the telecommunication links or any centralized energy management system. In order to validate the proposed method, the control system was implemented on a DC microgrid within MATLAB/SIMULINK, where the simulation results were analyzed and validated.
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.
The energy sector is moving into the era of distributed generation (DG) and microgrids
(MGs). The stability and operation aspects of converter-dominated DG MGs, however, are faced by
many challenges. To overcome these difficulties, this paper presents a new large-signal-based control
topology for DG power converters that is suitable for both grid connected and islanding modes of
operation without any need to reconfigure the control system and without islanding detection. To
improve MG stability and to guarantee stability and high performance of the MG system during sudden
harsh transients such as islanding, grid reconnection, and large load power changes, a nonlinear MG
stabilizer is proposed. We propose a novel control topology for microgrids which can work in both grid
connected and islanding modes without reconfiguration so it does not require islanding detection
technique, the controller is based on the concept of synchronverter In this paper, a radical step is taken
to improve the synchronverter as a self-synchronized synchronverter by removing the dedicated
synchronization unit
Solar Photovoltaic Generators with MPPT and Battery Storage in MicrogridsIAES-IJPEDS
Maximum power point tracking (MPPT) of a photo voltaic system with
different temperature and insolation conditions used for Micro grids can be
explained in this paper. The different steps of the design of this controller are
presented together with its simulation and the feasibility of control methods
to be adopted for the operation of a micro grid when it becomes isolated.
Normally, the micro grid operates in interconnected mode with the medium
voltage network; however, scheduled or forced isolation can take place.
In such conditions, the micro grid must have the ability to operate stably
and autonomously. An evaluation of the need of storage devices and load to
take off strategies is included in this paper. Solar photovoltaic (PV) energy
has witnessed double-digit growth in the past decade. The penetration of PV
systems as distributed generators in low-voltage grids has also seen
significant attention. In addition, the need for higher overall grid efficiency
and reliability has boosted the interest in the microgrid concept.
High-efficiency PV-based microgrids require maximum power point tracking
(MPPT) controllers to maximize the harvested energy due to the nonlinearity
in PV module characteristics. This paper proposes an approach
of coordinated and integrated control of solar PV generators with the
maximum power point tracking (MPPT) control and battery storage control
to provide voltage and frequency (V-f) support to an islanded microgrid.
The simulation studies are carried out with the IEEE 13-bus feeder test
system in grid connected and islanded microgrid modes. The MPPT
of a Photovoltaic System for Micro Grid operation is successfully designed
and simulated by using MATLAB/Simulink Software in this paper.
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.
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Author: Robbie Edward Sayers
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(C) 2024 Robbie E. Sayers
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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.
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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/
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Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Final project report on grocery store management system..pdfKamal Acharya
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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.
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COORDINATED CONTROL AND ENERGY MANAGEMENT OF DISTRIBUTED GENERATION INVERTERS IN A MICROGRID
1. NOVATEUR PUBLICATIONS
INTERNATIONAL JOURNAL OF INNOVATIONS IN ENGINEERING RESEARCH AND TECHNOLOGY [IJIERT]
ISSN: 2394-3696
VOLUME 2, ISSUE 5, MAY-2015
1 | P a g e
COORDINATED CONTROL AND ENERGY MANAGEMENT OF
DISTRIBUTED GENERATION INVERTERS IN A MICROGRID
Limbabai K Mudake
Department of Electrical Engineering
Fabtech College of Engineering and Research,
Sangola, INDIA
Prof.Shravan Kumar Akireddy
Department of Electrical Engineering
Fabtech College of Engineering and Research,
Sangola, INDIA
ABSTRACT
This project presents a micro grid consisting of different distributed generation (DG) units that
are connected to the distribution grid. The proposed micro grid consists of a photovoltaic (PV)
array which functions as the primary generation unit of the micro grid and a proton-exchange
membrane fuel cell to supplement the variability in the power generated by the PV array. The
control design for the DG inverters employs a new model predictive control algorithm which
enables faster computational time for large power systems by optimizing the steady-state and
the transient control problems separately.
The integration of renewable sources can supplement the generation from the distribution grid.
However, these renewable sources are intermittent in their generation and might compromise
the reliability and stability of the distribution network. As a result, energy-storage devices, such
as batteries and ultra-capacitors, are required to compensate for the variability in the renewable
sources. The incorporation of energy-storage devices is also critical for managing peak
demands and variations in the load demand.
So, in this project, a micro grid consisting of a photovoltaic (PV) array, a proton-exchange
membrane fuel cell (PEMFC), and a lithium-ion storage battery (SB) is proposed. The
proposed controller for the DG inverters is based on a newly developed MPC algorithm which
decomposes the control problem into steady-state and transient sub problems in order to reduce
the overall computation time.
The entire proposed system will be tested using MATLAB/SIMULINK and the simulation
results demonstrate the attractive performance characteristics of the proposed system.
KEYWORDS: Micro grid Analysis, Energy management technique
INTRODUCTION
Over the last decade, efficient and reliable communication and control technologies, coupled
with an increase in smarter electrical facilities, such as electric vehicles and smart meters, have
resulted in an increasing number of consumers participating in demand response management
(DRM) [1]–[5]. The current research is also focused on achieving a smarter grid through
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demand-side management (DSM), increasing energy reserves and improving the power quality
of the distribution system, such as harmonic compensation for nonlinear loads [5]–[8]. These
new trends enable higher levels of penetration of renewable generation, such as wind and solar
power into the grid. The integration of renewable sources can supplement the generation from
the distribution grid. However, these renewable sources are intermittent in their generation and
might compromise the reliability and stability of the distribution network. As a result, energy-
storage devices, such as batteries and ultra-capacitors, are required to compensate for the
variability in the renewable sources. The incorporation of energy-storage devices is also critical
for managing peak demands and variations in the load demand.
In this paper, a micro grid consisting of a photovoltaic (PV) array, a proton-exchange
membrane fuel cell (PEMFC), and a lithium-ion storage battery (SB) is proposed. The PEMFC
is used as a backup generator unit to compensate for the power generated by the intermittent
nature of the PV array. The SB is implemented for peak shaving during grid-connected
operation, and to supply power for any shortage in generated power during islanded operation
and to maintain the stability of the distribution network. An energy-management algorithm is
designed for the micro grid to coordinate the sharing of power among different DG units. The
proposed controller for the inverters of DG units is based on a newly developed model
predictive control (MPC) algorithm, which optimizes the steady-state and the transient control
problems separately. In this way, the computation time is greatly reduced.
In what follows, this paper provides a comprehensive solution for the operation of a microgrid
which will simultaneously dispatch real and reactive power during both grid-connected and
islanded operations, compensate for harmonics in the load currents, and perform peak shaving
and load shedding under different operating conditions.
Centralized Control for Parallel Operation of Distributed Generation Inverters in Micro
grids
This paper presents a centralized control system that coordinates parallel operations of different
distributed generation (DG) inverters within a microgrid. The control design for the DG
inverters employs a new Model Predictive Control algorithm that allows faster computational
time for large power systems by optimizing the steady-state and the transient control problems
separately. An overall energy management system is also implemented for the microgrid to
coordinate load sharing among different DG units during both grid-connected and islanded
operations. The design concept of the proposed control system is evaluated through simulation
studies under different test scenarios [19]. The impact of the increased penetration of DG units
on the distribution grid is also investigated using the proposed microgrid [20]. The simulation
results show that the operations of the DG units within the microgrid can be coordinated
effectively under the proposed control system to ensure stable operation of the overall
microgrid.
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Distributed control of hybrid AC-DC microgrid with solar energy, energy storage and
critical load
In this paper, a novel power flow control method for a hybrid AC-DC microgrid with solar
energy, and energy storage is proposed for the integration of a pulse load. This micro grid
works in islanding mode with a synchronous generator and PV farm supplying power to the
system's AC and DC sides, respectively. A bidirectional AC-DC inverter is used to link the AC
and DC sides by controlling the active and reactive power flow between them[21]. The PV
farm is connected to the DC bus through a DC-DC boost converter with maximum power point
tracking (MPPT) functionality. A Battery bank is connected to the DC bus through a
bidirectional DC-DC converter[22]. The system is tested with a pulse load connected to the AC
side. Simulation results verify that the proposed topology is coordinated for power
management in both the AC and DC sides under critical loads with high efficiency, reliability
and robustness in islanding modes.
Coordinating Storage and Demand Response for Microgrid Emergency Operation
Microgrids are assumed to be established at the low voltage distribution level, where
distributed energy sources, storage devices, controllable loads and electric vehicles are
integrated in the system and need to be properly managed. The microgrid system is a flexible
cell that can be operated connected to the main power network or autonomously, in a
controlled and coordinated way[23]. The use of storage devices in microgrids is related to the
provision of some form of energy buffering during autonomous operating conditions, in order
to balance load and generation. However, frequency variations and limited storage capacity
might compromise microgrid autonomous operation. In order to improve microgrid resilience
in the moments subsequent to islanding, this paper presents innovative functionalities to run
online, which are able to manage microgrid storage considering the integration of electric
vehicles and load responsiveness[24]. The effectiveness of the proposed algorithms is validated
through extensive numerical simulations.
Control Strategies of a DC Microgrid for Grid Connected and Islanded Operations
This paper proposes an algorithm for coordinated control of the distributed generators
integrated to a dc microgrid (DCMG), in islanded and grid connected modes of operation [25].
The proposed DCMG connects various types of nonconventional energy sources, storage
system to the dc, and three-phase, as well as single-phase ac loads. A control strategy for three-
phase voltage source inverter to integrate the three-phase load, as well as utility grid into the
DCMG, under various operating scenarios, has also been proposed[26]. The proposed control
strategy uses a combination of the feed-back and feed-forward control loops. Dual proportional
integral controllers for ac voltage regulation and inner current control have been suggested in
two rotating direct- and quadrature- axis synchronous reference frames for controlling the
respective positive and negative sequence components. Simulations are carried out to verify the
robustness of the proposed algorithm and control strategy under different operating conditions
including fault scenario and its effectiveness in maintaining the dc voltage of the microgrid.
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An improved control method of power electronic converters in low voltage micro-grid
With the increasing acceptance, micro-grid, combined with distributed generation (DG), may
be operated in two modes: grid-connected mode and island mode. In grid connected mode,
energy management is the control objective[27]. While in island mode, the control of Voltage
and frequency will take the place. The conventional droop control can perform the energy
management in grid-connected mode, but may not so effective when micro-grid transferring
between grid-connected mode and island mode. The paper analysis the micro-grid in different
modes (Conventional droop control, Voltage reference compensation, Constant power output
mode, Phase adjustment mode), and then proposes an overall control strategy for the micro-
grid. The voltage reference compensation would minimize the steady-state error on the
nominated operation point; the coordinate control of voltage and frequency with a feed forward
control of the voltage and frequency deviation added to power references could achieve
secondary regulation of the voltage and frequency[28]. In this paper, the authors take the
steady and transient transition of grid connecting and disconnecting of the micro-grid as an
example, and demonstrate that compensation on voltage reference is effective, and voltage and
frequency coordination control can well perform not only energy management in grid-
connected mode, but also the secondary regulation of voltage and frequency when micro-grid
separates from the main grid, and furthermore the strategy can perform well in the transition
states between the operation modes. The new droop control method has been validated through
simulations by PSCAD software and experiments.
Control Methods of Inverter-Interfaced Distributed Generators in a Microgrid System
Microgrids are a new concept for future energy distribution systems that enable renewable
energy integration and improved energy management capability[29]. Microgrids consist of
multiple distributed generators (DGs) that are usually integrated via power electronic inverters.
In order to enhance power quality and power distribution reliability, microgrids need to operate
in both grid-connected and island modes. Consequently, microgrids can suffer performance
degradation as the operating conditions vary due to abrupt mode changes and variations in bus
voltages and system frequency. This paper presents controller design and optimization methods
to stably coordinate multiple inverter-interfaced DGs and to robustly control individual
interface inverters against voltage and frequency disturbances [30]. Droop-control concepts are
used as system-level multiple DG coordination controllers, and control theory is applied to
device-level inverter controllers. Optimal control parameters are obtained by particle-swarm-
optimization algorithms, and the control performance is verified via simulation studies.
A microgrid energy management system with demand response
A new renewable and demand side coordinative energy management system is developed for
microgrid with demand response[31]. The microgrid is grid-connected, including photovoltaic
power generator (PV), energy storage device, and several industrial customers with adjustable
load. With the imported external power on time-of-use (TOU) price, an internal-dynamic-price-
based renewable and demand side coordinative energy management model is proposed based
on load and PV power forecasting results to maximize the profit of the renewable industrial
park with a microgrid. T he electricity demands of the rational customers interact mutually with
the day-ahead internal dynamic prices[32]. The customers' responsive behaviors are modeled
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using the matrix of self-elasticity and cross-elasticity. To solve the optimization model, a newly
proposed fruitfly optimization algorithm is adopted. Finally, simulation results of numerical
tests for a microgrid demonstrate the effectiveness of the model with demand response.
Energy management system for multi-microgrid
EMS of microgrid (I-IEMS) is developed to monitor and control distributed generator (DG). It
i s necessary to research practical I-IEMS for large-scale multi-microgrid. Energy Management
System for microgrid in this paper is based on Smart Grid Dispatching Technical Support
System (SGDTSS) which has been widely used in dispatching system of provincial or regional
power grid[33]. The secure operating system, database, SOA function, application interface
and mes sage bus are all included in special dispatching technical support platform for µEMS.
The functionalities of µEMS advanced application are presented, including topology engine
with multi-microgrid, power flow control, economic operation for microgrid, DGs & loads
forecast, demand response based on microgrid, “Seamless Transfer” between grid and island
mode, etc.
Microgrid energy management system: A study of reliability and economic issues
Microgrid (MG) is a prospective power system that addresses the renewable energy
technologies (RET) accompanying necessary growing deployment of distributed energy
resources (DER) and small-scale renewable energy sources (RES). This paper deals with the
economic and reliability issues in a MG[34]. A simulation model has been developed to
optimize the operation of MG economically. The objective function and constraints related to
the operation of MG are formulated and mathematical model is presented. A reliability study
has also been performed using a scenario-based approach to determine reliability index of the
system. The proposed formulation and model is validated with a case study followed by
conclusions and remarks.
Renewable based DC microgrid with energy management system
This paper explores the need for renewable based DC microgrid and proposes characteristic
features of a standalone DC microgrid[35]. The need for energy management system and its
role in DC microgrid has been emphasized. Renewable generating sources such as wind turbine
generator and photovoltaic panel require stringent control for harnessing maximum available
energy, energy storage system demands efficient management, and DC-link voltage must be
maintained constant. These requirements are fulfilled by energy management system, thus it
provides intelligence to the system and makes the microgrid reliable. An isolated renewable
DC microgrid having proposed features and energy management system has been simulated
using MATLAB/SIMULINK. The designed system sustains dynamic conditions and
simulation results validate feasibility of DC microgrid and energy management algorithm.
Energy management of a multi-agent based multi-microgrid system
This paper presents a model-based optimization algorithm for short-term energy trading in a
multi-microgrid system. The multi-microgrid system has a hierarchical design architecture
which is based on the Multi-Agent System (MAS) concept. Mixed-integer linear programming
(MILP) which takes into consideration multiple constraints is used to obtain the optimum
amount of power that will be generated, sold, or stored for the Energy Management System
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(EMS) of the multi-microgrid system at different time intervals[36]. By using the proposed
optimization algorithm, the EMS will ensure that power balance in the multi-microgrid system
is achieved through energy trading between different interconnecting microgrids. The proposed
optimization algorithm and hierarchical multi-microgrid system design architecture have the
capability to ensure that the multi-microgrid system operates in a coordinated and economic
manner. The design concept is demonstrated through different test case scenarios and the
results obtained are discussed.
Evaluating microgrid management and control with an implementable energy
management system
A microgrid can be characterized by its integration of distributed energy resources and
controllable loads. Such integration brings unique challenges to the microgrid management and
control which can be significantly different from conventional power systems[37]. Therefore, a
conventional energy management system (EMS) needs to be re-designed with consideration of
the unique characteristics of microgrids. To this end, we propose a microgrid EMS named a
microgrid platform (MP). We take into account all the functional requirements of a microgrid
EMS (i.e., forecast, optimization, data analysis, and human-machine interface) and address the
engineering challenges (i.e., flexibility, extensibility, and interoperability) in the design and
development of the MP. Moreover, we deploy the prototype system and conduct experiments
to evaluate the microgrid management and control in real-world settings at the UCLA Smart
Grid Energy Research Center. Our experimental results demonstrate that the MP is able to
manage various devices in the test bed, interact with the external systems, and perform optimal
energy scheduling and demand response.
Optimal energy management of a rural microgrid system using multi-objective
optimization
Electrification of rural areas has always been a challenge. In addition, large livestock farms
such as dairy farms, also face environmental problems due to inappropriate treatment of animal
wastes. Therefore, improvement of the electrical system in farms vis-a-vis efficient waste
management is of great importance to industry[38]. In this paper, a combined cooling, heating,
and power (CCHP) microgrid model was built to improve system efficiency of energy
utilization and lessen environmental problems caused by animal wastes based on multi-
objective optimization. In this proposed model, the animal manure is used to produce biogas,
which is used to feed internal combustion engines (ICEs), gas boilers, and absorption chillers.
The generated electricity would offset that would otherwise be bought from main grids. PV
generation is introduced to further increase the renewable fraction of energy contents. The
electrical storage is also included to balance power demand and power supply. To increase
system efficiency of energy utilization, coolant water from ICEs, plus their exhaust, could be
utilized based on the thermal storage modeled, by inclusion of absorption refrigerator and heat
exchanger. The final goal is to maximize energy output from distributed energy resources
(DERs) and meanwhile minimize daily system operating cost. Extra electricity generated
beyond the load demand could be used to charge battery storage. In this way, system energy
cost is reduced with energy system improvement and reconfiguration, and surrounding
environmental problems due to animal wastes are also lessened.
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Voltage and power management in a microgrid system with diesel generator and energy
storage
This paper presents results of the development of a voltage and power management system for
a microgrid. The microgrid under study is a power system located on the island with a peak
load of 1.8 MW connected to the main power grid via two submarine cables. Due to a long
radial network configuration with a high ratio of resistance to reactance, the system
experiences low voltages problems at remote locations. In addition, during peak load
conditions, thermal ratings of the submarine cables can be violated. Integration of the local
diesel generator and energy storage system is proposed to overcome existing problems. The
proposed voltage and power management scheme coordinates the on-load tap-changing
(OLTC) transformer, diesel generator and energy storage system of the microgrid. The scheme
ensures that the voltage profile of the microgrid is maintained within Electricity Code under
peak conditions. Results of the study are presented and discussed.
Microgrid wireless energy management with energy storage system
The penetration of renewable energy sources in small-scale power production gives the
opportunity parts of the grid to work as microgrids. The microgrid should be able to work both
in grid-connected and island mode, while its voltage and frequency deviations follow the EN
50160 standard. The use of energy storage system is generally recommended in order to absorb
the mismatches between the demand and the generation side and to preserve the quality of the
microgrid voltage [39]. While the up to day research is mainly concentrated on energy
management based on communication, this paper proposes a wireless method for keeping the
voltage and the frequency within the limits, using a battery as an energy storage system (ESS).
An analytical expression for calculating the battery capacity is also proposed. The active and
reactive power sharing among the parallel resources is achieved using the droop control
method and an algorithm proportional to droop characteristic and the rated apparent power of
each resource. According to the values of frequency and voltage and the State of Charge (SoC),
the battery is connected in the microgrid, working in charging or discharging mode. A
microgrid consisting of two inverter-interfaced power resources, a battery and a constant power
load is investigated. Simulation results demonstrate that the proposed wireless control method
provides the load with a high quality voltage in both grid-connected and islanded mode under
several load scenarios.
Optimal Energy Management for a Residential Microgrid Including a Vehicle-to-Grid
System
An optimization model is proposed to manage a residential microgrid including a charging spot
with a vehicle-to-grid system and renewable energy sources. In order to achieve a realistic and
convenient management, we take into account: (1) the household load split into three different
profiles depending on the characteristics of the elements considered; (2) a realistic approach to
owner behavior by introducing the novel concept of range anxiety; (3) the vehicle battery
management considering the mobility profile of the owner and (4) different domestic
renewable energy sources. We consider the microgrid operated in grid-connected mode. The
model is executed one-day-ahead and generates a schedule for all components of the microgrid.
The results obtained show daily costs in the range of 2.82 C = to 3.33 C =; the proximity of
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these values to the actual energy costs for Spanish households validate the modeling. The
experimental results of applying the designed managing strategies show daily costs savings of
nearly 10%.
An advanced energy management of microgrid system based on genetic algorithm
Immense growth has happened in the field of microgrid (MG) and the energy management
system (EMS) methods in the past decade. It is estimated that there is still a huge potential of
growth remaining in the field of EMS in the coming years. The main role of EMS is to
autonomously determine hour-by-hour the optimum dispatch of MG and main grid energy to
satisfy load demand needs. This paper is focused on developing an advanced EMS model able
to determine the optimal operating strategies regarding to energy costs minimization, pollutant
emissions reduction, MG system constraints and better utilization of renewable resources of
energy such as wind and photovoltaic through daily load demand. The proposed optimization
model of EMS is formulated and solved based on genetic algorithm (GA). The efficient
performance of the algorithm and its behavior is illustrated and analyzed in detail considering
winter load demand profile.
Environmental and economical optimization of microgrid long term operational planning
including PV-based active generators
Large scale penetration of Renewable Energy-Based Generators (REBG) and Distributed
Energy Resources (DER) requires an evolution of the classical dispatching of conventional
generators in power systems. A step towards the Smart Grid is to integrate locally REBG,
conventional generators and loads in clusters called microgrids. This paper presents a
microgrid energy management optimization in the presence of PV-based active generators.
Based on predictions of the available energy from PV generators, energy storage availability
and the power demand from the loads, the Microgrid Central Energy Management System
(MCEMS) elaborates a 24 hour ahead operational planning using the approach of unit
commitment by dynamic programming. The optimization objective function is the CO2
equivalent emissions (environmental criteria), the fuel consumption (economical criteria) or a
tradeoff between these two. In order to reduce uncertainty in forecasted values for PV
production or load demand, a medium term energy management recalculates the generators
power references one hour ahead if necessary.
Real-Time Energy Storage Management for Renewable Integration in Microgrid: An
Off-Line Optimization Approach
Microgrid is a key enabling solution to future smart grids by integrating distributed renewable
generators and storage systems to efficiently serve the local demand. However, due to the
random and intermittent characteristics of renewable energy, new challenges arise for the
reliable operation of microgrids. To address this issue, we study in this paper the real-time
energy management for a single microgrid system that constitutes a renewable generation
system, an energy storage system, and an aggregated load[40]. We model the renewable energy
offset by the load over time, termed net energy profile, to be practically predictable, but with
finite errors that can be arbitrarily distributed. We aim to minimize the total energy cost
(modeled as sum of time-varying strictly convex functions) of the conventional energy drawn
from the main grid over a finite horizon by jointly optimizing the energy charged/discharged
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to/from the storage system over time subject to practical load and storage constraints. To solve
this problem in real time, we propose a new off-line optimization approach to devise the online
algorithm. In this approach, we first assume that the net energy profile is perfectly predicted or
known ahead of time, under which we derive the optimal off-line energy scheduling solution in
closed-form. Next, inspired by the optimal off-line solution, we propose a sliding-window
based online algorithm for real-time energy management under the practical setup of noisy
predicted net energy profile with arbitrary errors. Finally, we conduct simulations based on the
real wind generation data of the Ireland power system to evaluate the performance of our
proposed algorithm, as compared with other heuristically designed algorithms, as well as the
conventional dynamic programming based solution.
Practice of microgrid control system
The system is based on the characteristics of microgrid and energy storage power plant control
system, combined with engineering practice, providing monitoring for the island-based
independent power supply systems, science parks, research institutes, laboratories microgrid,
energy storage power stations, control, protection and energy management integration
solutions[41]. For system integration process, control equipment and integrated communication
protocol differences difficulties brought by reference to IEC61850 specifications for device
modeling and functionally related logical nodes (Logical Node, LN) carried out the necessary
expansion of the unified communications follow IEC61850 specification. System uses a multi-
division, multi-modal coordination and management structures and ways of using
programmable logic and network operation, as well as isolated operation mode switching
operation mode strategies to build the library organized package to meet the needs of different
projects and projects[41]. Through various forms of microgrid internal energy and load
forecasting and scientific precision scheduling, coordination and optimization of microgrid and
microgrid, microgrid and large grid network to achieve energy efficient use of energy to meet a
variety of user needs, improve supply reliability and other purposes.
Energy Management in the Decentralized Generation Systems Based on Renewable
Energy—Ultra capacitors and Battery to Compensate the Wind/Load Power Fluctuations
This paper presents the energy management for the decentralized generation systems (DGS)
using the wind turbine with photovoltaic (PV) panels and the energy storage devices. For a
high penetration level of the wind/PV generation, the energy storage device with a fast
response is necessary to cover the shortfall or overflow of generation due to sudden variations
of the wind or the sun. In addition, the requested energy by the residential appliances presents
random behaviour, which can be lower or higher than the produced energy from the renewable
sources. Using the wind turbine and the PV power generation system with energy storage will
reduce the fluctuations of the wind power and the load ones. The energy storage system
requires capital investment; thus, it is important to estimate the reasonable storage capacities
without an overflow size for the desired applications. In addition, a good strategy for energy
management is necessary to reduce the variation impacts of the wind energy and the load for
the battery and the residential appliances. The contribution of this paper is focused on energy
management based on the frequency approach using the wind/load's fluctuating power sharing
and the polynomial controllers. First, this method enables reducing for the battery and the
microgrid the impacts of the micro cycles due to the wind/load's power fluctuations. Second, it
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allows estimating the energy storage capacity without the overflow size. The performances of
the proposed method are evaluated through some simulations and experimental tests using the
summer load profile and the winter ones.
Coordination of Generation Scheduling with PEVs Charging in Industrial Microgrids
Conventional industrial microgrids (IMGs) consist of factories with distributed energy
resources (DERs) and electric loads that rely on combined heat and power (CHP) systems
while the developing IMGs are expected to also include renewable DERs and plug-in electric
vehicles (PEVs) with different vehicle ratings and charging characteristics. This paper presents
an electricity and heat generation scheduling method coordinated with PEV charging in an
IMG considering photovoltaic (PV) generation systems coupled with PV storages. The
proposed method is based on dynamic optimal power flow (DOPF) over a 24-hour period and
includes security-constrained optimal power flow (SCOPF), IMG's factories constraints, PV
storage constraints and PEVs dynamic charging constraints. It will utilize the generators waste
heat to fulfill thermal requirements while considering the status of renewable DERs to decrease
the overall cost of IMGs. To demonstrate the effectiveness of the proposed method, detailed
simulation results are presented and analyzed for an 18-bus IMG consisting of 12 factories and
6 types of PEVs without/with PV generation systems operating in grid-connected and stand-
alone modes. The main contribution is including PEVs with dynamic constraints that have
changed the nature of scheduling formulation from a simple hourly OPF to a dynamic OPF.
Control Methods of Inverter-Interfaced Distributed Generators in a Microgrid System
Microgrids are a new concept for future energy distribution systems that enable renewable
energy integration and improved energy management capability. Microgrids consist of multiple
distributed generators (DGs) that are usually integrated via power electronic inverters. In order
to enhance power quality and power distribution reliability, microgrids need to operate in both
grid-connected and island modes. Consequently, microgrids can suffer performance
degradation as the operating conditions vary due to abrupt mode changes and variations in bus
voltages and system frequency. This paper presents controller design and optimization methods
to stably coordinate multiple inverter-interfaced DGs and to robustly control individual
interface inverters against voltage and frequency disturbances. Droop-control concepts are used
as system-level multiple DG coordination controllers, and control theory is applied to device-
level inverter controllers. Optimal control parameters are obtained by particle-swarm-
optimization algorithms, and the control performance is verified via simulation studies.
Coordinated Energy Management of Networked Microgrids in Distribution Systems
This paper proposes a novel control strategy for coordinated operation of networked microgrids
(MGs) in a distribution system. The distribution network operator (DNO) and each MG are
considered as distinct entities with individual objectives to minimize the operation costs. It is
assumed that both the dispatch able and nondispatchable distributed generators (DGs) exist in
the networked MGs. In order to achieve the equilibrium among all entities and take into
account the uncertainties of DG outputs, we formulate the problem as a stochastic bi-level
problem with the DNO in the upper level and MGs in the lower level. Each level consists of
two stages. The first stage is to determine base generation set points based on the load and
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nondispatchable DG output forecasts and the second stage is to adjust the generation outputs
based on the realized scenarios. A scenario reduction method is applied to enhance a tradeoff
between the accuracy of the solution and the computational burden. Case studies of a
distribution system with multiple MGs of different types demonstrate the effectiveness of the
proposed methodology. The centralized control, deterministic formulation, and stochastic
formulation are also compared.
Coordination of control and energy management methods for microgrid systems
Microgrid is a promising paradigm for the large scale integration of DER in distribution
networks. This paper addresses the state of the art in the conception, operation and design of
microgrids. It also discusses the impact and contributions to distribution grids of multiple
microgrids, coordinated through an aggregator agent. Microgrids may operate as isolated
electrical systems in case of contingency in the distribution network; a comprehensive analysis
on the energy management system and stabilizing control for such operation mode, as well as
for the grid connected mode, is provided. This paper reflects the vision of the Catalonia
Institute for Energy Research (IREC) for near future microgrids based on the experience of its
laboratory test bed.
CONCLUSION
In this project, a control system that coordinates the operation of multiple distributed
generation inverters in a microgrid for grid-connected and islanded operations will be
presented. The proposed controller for the distributed generation inverters is based on a newly
developed model predictive control algorithm which decomposes the control problem into
steady-state and transient sub problems in order to reduce the overall computation time.
REFERENCES
[1] A. Tuladhar , H. Jin , T. Unger and K. Mauch "Parallel operation of single phase inverter
modules withno control interconnections", Proc. 12th Annu.Appl. Power Electron. Conf.
Expo., vol. 1, pp.94 -100 1997
[2] B. Lasseter "Microgrids [distributed powergeneration]", Proc. IEEE Power Eng. Soc.
WinterMeeting 2001, vol. 1, pp.146 -149 2001
[3] A. Gosh and G. Ledwich Power Quality Enhancement Using Custom Power Devices,
pp.380 -406 2002 :Kluwer[CrossRef]
[4] V. Moreno , A. Pigazo and R. I. Diego "Reference estimation technique for active power
filters using a digital Kalman algorithms", Proc. Int. Conf. Harmonics Qual. Power, vol. 2,
pp.490 -494 2002
[5] R. Lasseter , A. Akhil , C. Marnay , J. Stevens , J. Dagle , R. Guttromson , A. S.
Meliopoulous , R. Yinger and J. Eto Integration of distributed energy resources—
TheCERTSmicrogrid concept,, 2003
12. NOVATEUR PUBLICATIONS
INTERNATIONAL JOURNAL OF INNOVATIONS IN ENGINEERING RESEARCH AND TECHNOLOGY [IJIERT]
ISSN: 2394-3696
VOLUME 2, ISSUE 5, MAY-2015
12 | P a g e
[6] G. C. Heffner , C. A. Goldman and M. M. Moezzi "Innovative approaches to verifying
demand response of water heater load control", IEEE Trans. Power Del., vol. 21, no. 1,
pp.1538 -1551 2006
[7] J. A. Macias and A. Gomez "Self-tuning of Kalman filters for harmonic computation",
IEEE Trans. Power Del., vol. 21, no. 1, pp.501 -503 2006
[8] R. H. Lasseter Control and design of microgrid components, 2006
[9] Blaabjerg, F., Teodorescu, R., Liserre, M., Timbus, A.V., "Overview of Control and Grid
Synchronization for Distributed Power Generation Systems", Industrial Electronics, IEEE
Transactions on, Volume 53, Issue 5, On page(s): 1398-1409, Oct. 2006.
[10] M. Coleman , C. K. Lee , C. Zhu and W. G. Hurley "State-of-charge determination from
EMF voltage estimation: Using impedance, terminal voltage, and current for lead-acid and
lithium-ion batteries", IEEE Trans. Ind. Electron., vol. 54, no. 5, pp.2550 -2557 2007
[11] J. M. Guerrero , J. Matas , L. GarcíadeVicuña , M. Castilla and J. Miret
"Decentralized control for parallel operation of distributed generation inverters using resistive
output impedance", IEEE Trans. Ind. Electron., vol. 54, no. 2, pp.994 -1004 2007
[12] N. Hatziargyriou , H. Asano , R. Iravani and C. Marnay "Microgrids", IEEE Power
Energy Mag., vol. 5, no. 4, pp.78 -94 2007
[13] J. Tomic and W. Kempton "Using fleets of electric-drivevehicles for grid support", J.
Power Sources, vol. 168, no. 2, pp.459 -468 2007
[14] Huang Jiayi, "A review on distributed energy resources and MicroGrid," Renewable and
Sustainable Energy Reviews 12 (2008) 2472-2483.
[15] c. K. Sao and P. W. Lehn, "Control and power management of converterfedMicroGrids,"
IEEE Trans. Power Syst., vol. 23, no. 3, pp. 1088-1098, Aug. 2008
[16] G. Strbac "Demand side management: Benefitsand challenges", Energy Policy, vol. 36,
no. 12, pp.4419 -4426 2008
[17] F. Katiraei, R. Iravani, N. Hatziargyriou, and A. Dimeas, "Microgrids management," IEEE
Power Energy Mag., vol. 6, no. 3, pp. 54-65, May 2008.
[18] S. Diaf, G. Notton, M. Belhamel, M. Haddadi, and A. Louche, "Design and techno-
economical optimization for hybrid PV/wind system under various meteorological conditions,"
Applied Energy, v.85, pp. 968-987, 2008.
[19] F. Katiraei, R. Iravani, N. Hatziargyriou and A. Dimeas, "Microgrids Management", IEEE
Power & Energy Magazine, Vol. 6, No. 3, pp. 54-65, 2008.
[20] N. Jenkins , J. Ekanayake and G. Strbac Distributed Generation, 2009 :IET
13. NOVATEUR PUBLICATIONS
INTERNATIONAL JOURNAL OF INNOVATIONS IN ENGINEERING RESEARCH AND TECHNOLOGY [IJIERT]
ISSN: 2394-3696
VOLUME 2, ISSUE 5, MAY-2015
13 | P a g e
[21] S. Chowdhury , S. P. Chowdhury and P. CrossleyMicrogrids and Active Distribution
Networks, 2009 :IET
[22] A. Yazdani and P. P. Dash "A control methodology and characterization of dynamics for
a photovoltaic (PV) system interfaced with a distribution network", IEEE Trans. Power Del.,
vol. 24, no. 3, pp.1538 -1551 2009
[23] Wei Li, Ching-Nan Kao. An Accurate Power Control Strategy for Power-Electronics-
Interfaced Distributed Generation Units Operation ina Low-Voltage MultibusMicrogrid. IEEE
TRANSATIONS ON POWER ELECTRONICS, VOL 24. NO 12.DECEMBER 2009
[24] R. Zamora and A. K. Srivastava "Controls for microgrids with storage: Review,
challenges, and research needs", J. Renew. Sustain. Energy Rev., vol. 14, no. 7, pp.2009 -
2018 2010
[25] S. Braithwait "Behavior management", IEEE Power and Energy Mag., vol. 8, no. 3,
pp.36 -45 2010
[26] R. Lasseter , J. Eto , B. Schenkman , J. Stevens , H. Vollkommer , D. Klapp , E. Linton ,
H. Hurtado and J. Roy "Certs microgrid laboratory test bed, and smart loads", IEEE Trans.
Power Del., vol. 26, no. 1, pp.325 -332 [6] A. Molderink , V. Bakker , M. G. C. Bosman , J.
L. Hurink and G. J. M. Smit "Management and control of domestic smart grid technology",
IEEE Trans. Smart Grid, vol. 1, no. 2, pp.109 -119 2010
[27] A. Mohsenian-Rad , V. W. S. Wong , J. Jatskevich , R. Schober and A. Leon-Garcia
"Autonomous demand-side management based on game-theoretic energy consumption
scheduling for the future smart grid", IEEE Trans. Smart Grid, vol. 1, no. 3, pp.320 -331
2010
[28] K. T. Tan , P. L. So , Y. C. Chu and K. H. Kwan "Modeling, control and simulation of a
photovoltaic power system for grid-connected and stand-alone applications", Proc. Int. Power
Energy Conf., vol. 56, pp.608 -613 2010
[29] M. Charkhgard and M. Farrokhi "State-of-charge estimation for lithium-ion batteries
using neural networks and EKF", IEEE Trans. Ind. Electron., vol. 57, no. 12, pp.4178 -4187
2010
[30] X. Zhang, G. G. Karady and Y. Guan, "Design methods investigation for residential
microgrid infrastructure," Euro. Trans. Electr. Power, 2010
[31] C. L. Chen , Y. B. Wang , J. S. Lai , Y. S. Lai and D. Martin "Design of parallel inverters
for smooth mode transfer of microgrid applications", IEEE Trans. Ind. Electron., vol. 25, no.
1, pp.6 -15 2010
[32] J. Mattingley , Y. Wang and S. Boyd "Receding horizon control: Automatic generation of
high-speed solvers", IEEE Control Syst. Mag., vol. 31, no. 3, pp.52 -65 2011
14. NOVATEUR PUBLICATIONS
INTERNATIONAL JOURNAL OF INNOVATIONS IN ENGINEERING RESEARCH AND TECHNOLOGY [IJIERT]
ISSN: 2394-3696
VOLUME 2, ISSUE 5, MAY-2015
14 | P a g e
[33] M. Agrawal, A. Mittal, "Micro Grid Technological Activities across the Globe: A
Review", International Journal of Research and Reviews in Applied Sciences, Vol.7, Issue 2,
May 2011
[34] L. Xu, D. Chen, "Control and Operation of a DC Microgrid with Variable Generation and
Energy Storage", IEEE Transactions on Power Delivery, Vol.26, Issue 4, Oct 2011.
[35] W. Shi and V. W. S. Wong "Real-time vehicle-to-grid control algorithmunder price
uncertainty", Proc. 2011 IEEE SmartGridComm, pp.261 -266
[36] N.W.A. Lidula, A.D. Rajapakse, "Microgrids research: A review of experimental
microgrids and test systems," Renewable and Sustainable Energy Reviews 15 (2011) 186-202.
[37] W. Su and J. Wang, "Energy management systems in microgrid operations," The
Electricity J., vol. 25, no. 8, pp. 45-60, Oct. 2012.
[38] A. Mohamed, F. Carlos, T. Ma, M. Farhadi, O. Mohammed, "Operation and protection of
photovoltaic systems in hybrid AC/DC smart grids," IECON 2012-38th Annual Conference on
IEEE Industrial Electronics Society, pp.11 04-11 09,25-28 Oct. 2012
[39] C. M. Colson and M. H. Nehrir "Comprehensive real-time microgrid power management
and control with distributed agents", IEEE Trans. Smart Grid, vol. 4, no. 1, pp.617 -627
2013
[40] M. Y. Zhai "Transmission characteristics of low-voltage distribution networks in China
under the smart grids environment", IEEE Trans. Power Del., vol. 26, no. 1, pp.173 -180