This document summarizes a research paper on a Z-source multi-level inverter based PV generation system. The paper proposes using a Z-source multi-level inverter instead of a conventional voltage source inverter to improve system performance. It presents mathematical models of the PV panel, Z-source inverter, and MPPT technique. Simulation results show that the Z-source multi-level inverter provides boosting capability, reduces harmonics, and improves efficiency compared to a conventional voltage source inverter for solar energy conversion. The system is able to efficiently supply both linear and non-linear loads.
Hardware Implementation of Solar Based Boost to SEPIC Converter Fed Nine Leve...IJPEDS-IAES
Multi level inverters are widely used in high power applications because of
low harmonic distortion. This paper deals with the simulation
and implementation of PV based boost to SEPIC converter with multilevel
inverter. The output of PV system is stepped up using boost to sepic
converter and it is converted into AC using a multilevel inverter.
The simulation and experimental results with the R load is presented in this
paper. The FFT analysis is done and the THD values are compared. Boost to
SEPIC converter is proposed to step up the voltage to the required value. The
experimental results are compared with the simulation results. The results
indicate that nine level inverter system has better performance than seven
level inverter system.
A Novel Three Phase Multi-string Multilevel Inverter with High DC-DC Closed o...rnvsubbarao koppineni
this inverter reduces
number power devices and high performances.
Before this inverter provide a high step up DC-DC
converter with PI controller for better conversion
efficiency and to improve the output dc voltage of
varies renewable energy sources. This multi-string
multilevel inverter consists of six switches only
instead of eight switches in cascaded H-bridge
multilevel inverter in order to reduce conversion
losses. The main objective of this paper is to save
cost and size by removing any kind of transformer
as well as reducing the power devices
Filter Based Solar Power Generation System with a Seven Level InverterIJMTST Journal
This paper proposes a new solar power generation system, which is composed of a DC/DC power converter and a new seven-level inverter. The DC/DC power converter integrates a DC-DC boost converter and a transformer to convert the output voltage of the solar cell array into two independent voltage sources with multiple relationships. This new seven-level inverter is configured using a capacitor selection circuit and a full-bridge power converter, connected in cascade. The capacitor selection circuit converts the two output voltage sources of DC-DC power converter into a three-level DC voltage and the full- bridge power converter further converts this three- level DC voltage into a seven-level AC voltage. In this way, the proposed solar power generation system generates a sinusoidal output current that is in phase with the utility voltage and is fed into the utility. The salient features of the proposed seven-level inverter are that only six power electronic switches are used and only one power electronic switch is switched at high frequency at any time. A prototype is developed and tested to verify the performance of this proposed solar power generation system.
Nine Level Inverter with Boost Converter from Renewable Energy SourceIJERA Editor
A new single phase nine level multilevel inverter is proposed. The input to the proposed nine level multilevel inverter is obtained from solar panel . The solar energy obtained from the solar panel is not constant and it varies with times. In order to maintain the constant voltage obtained from the solar panel the boost converter is used to maintain the constant output voltage using MPPT ( Perturb and observe algorithm) algorithm. Then the buck boost converter output voltage is stored in the battery bank. Finally the battery energy is connected to the 9 level inverter circuits. The harmonics in the inverter is eliminated by using the fuzzy logic controller. The gate pulse for the multilevel inverter is given by the fuzzy logic controller which in turn reduces the harmonics in the inverter. Then the inverter output is connected to the grid are some application.
Simulation of various DC-DC converters for photovoltaic systemIJECEIAES
This work explains the comparison of various dc-dc converters for photovoltaic systems. In recent day insufficient energy and continues increasing in fuel cost, exploration on renewable energy system becomes more essential. For high and medium power applications, high input source from renewable systems like photovoltaic and wind energy system turn into difficult one, which leads to increase of cost for installation process. So the generated voltage from PV system is boosted with help various boost converter depends on the applications. Here the various converters are like boost converter, buck converter, buck-boost converter, cuk converter, sepic converter and zeta converter are analysed for photovoltaic system, which are verified using matlab / simulink.
Hardware Implementation of Solar Based Boost to SEPIC Converter Fed Nine Leve...IJPEDS-IAES
Multi level inverters are widely used in high power applications because of
low harmonic distortion. This paper deals with the simulation
and implementation of PV based boost to SEPIC converter with multilevel
inverter. The output of PV system is stepped up using boost to sepic
converter and it is converted into AC using a multilevel inverter.
The simulation and experimental results with the R load is presented in this
paper. The FFT analysis is done and the THD values are compared. Boost to
SEPIC converter is proposed to step up the voltage to the required value. The
experimental results are compared with the simulation results. The results
indicate that nine level inverter system has better performance than seven
level inverter system.
A Novel Three Phase Multi-string Multilevel Inverter with High DC-DC Closed o...rnvsubbarao koppineni
this inverter reduces
number power devices and high performances.
Before this inverter provide a high step up DC-DC
converter with PI controller for better conversion
efficiency and to improve the output dc voltage of
varies renewable energy sources. This multi-string
multilevel inverter consists of six switches only
instead of eight switches in cascaded H-bridge
multilevel inverter in order to reduce conversion
losses. The main objective of this paper is to save
cost and size by removing any kind of transformer
as well as reducing the power devices
Filter Based Solar Power Generation System with a Seven Level InverterIJMTST Journal
This paper proposes a new solar power generation system, which is composed of a DC/DC power converter and a new seven-level inverter. The DC/DC power converter integrates a DC-DC boost converter and a transformer to convert the output voltage of the solar cell array into two independent voltage sources with multiple relationships. This new seven-level inverter is configured using a capacitor selection circuit and a full-bridge power converter, connected in cascade. The capacitor selection circuit converts the two output voltage sources of DC-DC power converter into a three-level DC voltage and the full- bridge power converter further converts this three- level DC voltage into a seven-level AC voltage. In this way, the proposed solar power generation system generates a sinusoidal output current that is in phase with the utility voltage and is fed into the utility. The salient features of the proposed seven-level inverter are that only six power electronic switches are used and only one power electronic switch is switched at high frequency at any time. A prototype is developed and tested to verify the performance of this proposed solar power generation system.
Nine Level Inverter with Boost Converter from Renewable Energy SourceIJERA Editor
A new single phase nine level multilevel inverter is proposed. The input to the proposed nine level multilevel inverter is obtained from solar panel . The solar energy obtained from the solar panel is not constant and it varies with times. In order to maintain the constant voltage obtained from the solar panel the boost converter is used to maintain the constant output voltage using MPPT ( Perturb and observe algorithm) algorithm. Then the buck boost converter output voltage is stored in the battery bank. Finally the battery energy is connected to the 9 level inverter circuits. The harmonics in the inverter is eliminated by using the fuzzy logic controller. The gate pulse for the multilevel inverter is given by the fuzzy logic controller which in turn reduces the harmonics in the inverter. Then the inverter output is connected to the grid are some application.
Simulation of various DC-DC converters for photovoltaic systemIJECEIAES
This work explains the comparison of various dc-dc converters for photovoltaic systems. In recent day insufficient energy and continues increasing in fuel cost, exploration on renewable energy system becomes more essential. For high and medium power applications, high input source from renewable systems like photovoltaic and wind energy system turn into difficult one, which leads to increase of cost for installation process. So the generated voltage from PV system is boosted with help various boost converter depends on the applications. Here the various converters are like boost converter, buck converter, buck-boost converter, cuk converter, sepic converter and zeta converter are analysed for photovoltaic system, which are verified using matlab / simulink.
The battery energy storage systems are very essential for maintaining constant power supply when using solar photovoltaic systems for power generation. The viability and ability of battery energy storage systems are assessed based on battery usage in Solar Photovoltaic utility grid-connected systems. The power supply quality and reliability are improved by utilizing battery energy storage technologies in conjunction with solar photovoltaic systems. This paper presents a comparative analysis of Lead-Acid Storage battery and Lithium-ion battery banks connected to a utility grid. The battery mathematical model simulation study gives their performance characteristics of these batteries under grid-connected loads. Cost-benefit analysis of battery usage for determining the best battery suitable for solar photovoltaic system applications is also presented in this paper.
Push-Pull Converter Fed Three-Phase Inverter for Residential and Motor LoadIJPEDS-IAES
The proposed paper is an new approach for power conditioning of a PV
(photo-voltaic) cell array. The main objective is to investigate an approach to
provide and improve the delivered electric energy by means of power
conditioning structures with the use of alternative renewable resources
(ARRs) for remote rural residential or industrial non-linear loads. This
approach employs a series-combined connected boost and buck boost DCDC
converter for power conditioning of the dc voltage provided by a photovoltaic
array. The input voltage to the combined converters is 100 V
provided from two series connected PV cells, which is converted and
increased to 200 V at the dc output voltage. Series-combined connected
boost and buck-boost DC-DC converters operate alternatively. This helps to
reduce the input ripple current and provide the required 400 Vdc on a
sinusoidal PWM three-phase inverter. Analysis of the two series-combined
DC-DC converters is presented along with simulation results. Simulations of
the series-combined DC-DC converters are presented with an output DC
voltage of 200 V and a maximum output load of Po=600 W.
Operational performance of a PV generator feeding DC shunt and induction moto...IJECEIAES
This paper presented the transient and operational behavior of a parallel Combination of DC Shunt Motor and IM fed by a photovoltaic generator at different solar irradiance levels. The maximum power point of current/voltage (I/V) characteristic of the PV generator was achieved for different solar intensities, by utilizing an open circuit voltage method. The nonlinear operational behavior of (I/V) characteristics of the PV generator at various solar intensities and the magnetization curve of the ferromagnetic material of the DC shunt motor were both modeled by high order polynomial mathematical expressions. The study investigated the response of the system at different solar irradiance levels and changing the torque loads for both motors and then following step change in solar intensity levels with fixed loading torques for both motors. All numerical simulations were executed using MATLAB software.
High Proficiency Grid ConnectedPhotovoltaic Power Generation SystemIJRES Journal
Solar energy hasbecomepopular nowadays and desire for clean energy. Since the solar radiation on no occasion remains constant,it keeps on insecure throughout the day. The need of the hour is to distribute a constant voltage to the grid irrespective of the deviation in temperatures and solar insolation. The inverter is designed from a boost converter along with a line frequency. The voltage from the boost converter is fedto the grid through inverter. In this proposed method high efficiency can be achievedby using only one switch functioning at high frequency at a time. The converter uses IGBT and ultra-fast reverse recovery diode. The simulation and experiment results are verified using MATLAB/Simulink software.
The real problems in diminution of power quality occurs due to the rapid growth of nonlinear load are leads to sudden decrease of source voltage for a few seconds i.e sag, swell, harmonics in source and load current, voltage unbalance etc. All these problems can be compensated by using Unified Power Quality Controller (UPQC) and the operation of UPQC depends upon the available voltage across capacitor present in dc link. If the capacitor voltage is maintained constant then it gives satisfactory performance. The proposed research is basically on designing of Photo Voltaic (PV) /Wind energy fed to the dc link capacitor of UPQC so as to maintain proper voltage across it and operate the UPQC for power quality analysis. The said model is simulated in Matlab and results are verified by using FFT analysis.The proposed PV/ Wind energy-UPQC is design in Matlab simulation for reduction of voltage sag, swell, interruption of voltage, harmonics in load current and compensation of active and reactive power.
In this paper a buck-boost dc-dc converter for pv application is proposed, which is mainly composed of a buck – boost converter, PV panel, load and a battery. Existing dc-dc converter can convert the power from the PV panel, but unfortunately the PV panel can only provide power when there is a high intensity of light. In order to provide power supply to the load without any interruption, buck-boost dc-dc converter is introduced. The power intermittency issue of PV panel can be overcome with the aid of a secondary supply which is in this case, the batter. The integration system between the primary and the secondary supply is controlled by a simple proposed control scheme. Battery act as a power in the low voltage side while PV panel is taking over in the high voltage side. Buck-boost converter is operated either is buck or boost mode according to the performance of the PV panel. This paper is presented the simple control scheme to decide the mode suitable for the buck and boost mode. Various conditions are simulated to verify the working operation of the buck-boost converter and to representing solar panel in real life. Simulation and experimental are carried out to verify the system.
Analysis of Fuel Cell Based Multilevel DC-DC Boost Converter for Induction MotorIJMTST Journal
In this paper new topologies and interleaving modulation concepts for multilevel DC-DC boost converter
enabling a significantly less loss and a reduced chip size of the power semiconductors are proposed. The
distributed generation (DG) systems based on the renewable energy sources have rapidly developed in
recent years. These DG systems are powered by micro sources such as fuel cells, photovoltaic (PV) systems,
and batteries. Fuel cells are considered to be one of the most promising sources of distributed energy because
of their high efficiency, low environmental impact and scalability. Non-isolated high step-up DC-DC
converters are required in the industrial applications. Many of these conventional DC–DC converters have the
disadvantages of operating at high duty-cycle, high switch voltage stress and high diode peak current. A
three-level step up converter is implemented to boost the fuel cell stack voltage of 96V to 340V. The proposed
converter consists a system of fuel cell based Multilevel DC-DC converter with PI controller is modeled and
simulated by using Matlab/Simulink.
Real Time Implementation of Variable Step Size Based P&O MPPT for PV Systems ...IJPEDS-IAES
Nowadays Solar energy is an important energy source due to the energy crisis and environment pollution. Maximum power point tracking (MPPT) algorithm improves the utilization efficiency of a photovoltaic systems. In this paper an improved P&O MPPT algorithm is developed and simulated using MATLAB / SIMULINK to control the DC/DC buck converter. The obtained simulink model is also verified using dspace tool. Both the simulated and experimental results are validated by also comparing them with conventional MPPT methods. The performance measures show the increase in the efficiency of PV system by the proposed model.
Basic MOSFET Based vs Couple-Coils Boost Converters for Photovoltaic GeneratorsIJPEDS-IAES
Considering the optimization of a photovoltaic system, several studies show the advantage in the choice of a distributed structure. For such structures small power converters such as the boosts and buck converters appear as most appropriate. We have analysed the efficiency of small power boost- converters especially dedicated for photovoltaic energy conversion systems working in the middle and high voltage ranges. The setup studied is a photovoltaic generator connected to an AC grid working in 230 Volts via an inverter. Moreover, we considered the possibility of multiple electrical energy sources as photovoltaic, wind systems in the same energy production system, which obliged an adaptive converter structure. We evaluated the losses in the various stages of a boost converter and point out the importance of the power MOSFET used as the commutation element. New transistors databases obtained from manufacturers show the nonlinear dependency between the resistance drain-source when passing, Rdson and the maximum rating voltage when the transistor is off, Vdsmax, for all transistor families. Thus nonlinear dependency induces a huge increase of losses with the voltage in the MOSFET, and as a direct consequence in the converter the more as Vdsmax is higher. In order to minimize losses of the converter we have designed and realized a new high efficiency version of a Step-Up structure based on a commutation element integrating a low Vdsmax voltage MOSFET and very low Rdson.
Презентація до мого майстер-класу у київському Freud House 21 жовтня 2014.
Трішки про те, як, я вірю, працює цей світ, про персональний продукт, цінність, просування та розвиток "бізнесу".
Головна думка презентації:
«Навіть, якщо ви працюєте «на когось», ви можете вже з цього моменту ставитись до роботи з «відповідальністю власного бізнесу» - своєї корпорації «Я»!
The battery energy storage systems are very essential for maintaining constant power supply when using solar photovoltaic systems for power generation. The viability and ability of battery energy storage systems are assessed based on battery usage in Solar Photovoltaic utility grid-connected systems. The power supply quality and reliability are improved by utilizing battery energy storage technologies in conjunction with solar photovoltaic systems. This paper presents a comparative analysis of Lead-Acid Storage battery and Lithium-ion battery banks connected to a utility grid. The battery mathematical model simulation study gives their performance characteristics of these batteries under grid-connected loads. Cost-benefit analysis of battery usage for determining the best battery suitable for solar photovoltaic system applications is also presented in this paper.
Push-Pull Converter Fed Three-Phase Inverter for Residential and Motor LoadIJPEDS-IAES
The proposed paper is an new approach for power conditioning of a PV
(photo-voltaic) cell array. The main objective is to investigate an approach to
provide and improve the delivered electric energy by means of power
conditioning structures with the use of alternative renewable resources
(ARRs) for remote rural residential or industrial non-linear loads. This
approach employs a series-combined connected boost and buck boost DCDC
converter for power conditioning of the dc voltage provided by a photovoltaic
array. The input voltage to the combined converters is 100 V
provided from two series connected PV cells, which is converted and
increased to 200 V at the dc output voltage. Series-combined connected
boost and buck-boost DC-DC converters operate alternatively. This helps to
reduce the input ripple current and provide the required 400 Vdc on a
sinusoidal PWM three-phase inverter. Analysis of the two series-combined
DC-DC converters is presented along with simulation results. Simulations of
the series-combined DC-DC converters are presented with an output DC
voltage of 200 V and a maximum output load of Po=600 W.
Operational performance of a PV generator feeding DC shunt and induction moto...IJECEIAES
This paper presented the transient and operational behavior of a parallel Combination of DC Shunt Motor and IM fed by a photovoltaic generator at different solar irradiance levels. The maximum power point of current/voltage (I/V) characteristic of the PV generator was achieved for different solar intensities, by utilizing an open circuit voltage method. The nonlinear operational behavior of (I/V) characteristics of the PV generator at various solar intensities and the magnetization curve of the ferromagnetic material of the DC shunt motor were both modeled by high order polynomial mathematical expressions. The study investigated the response of the system at different solar irradiance levels and changing the torque loads for both motors and then following step change in solar intensity levels with fixed loading torques for both motors. All numerical simulations were executed using MATLAB software.
High Proficiency Grid ConnectedPhotovoltaic Power Generation SystemIJRES Journal
Solar energy hasbecomepopular nowadays and desire for clean energy. Since the solar radiation on no occasion remains constant,it keeps on insecure throughout the day. The need of the hour is to distribute a constant voltage to the grid irrespective of the deviation in temperatures and solar insolation. The inverter is designed from a boost converter along with a line frequency. The voltage from the boost converter is fedto the grid through inverter. In this proposed method high efficiency can be achievedby using only one switch functioning at high frequency at a time. The converter uses IGBT and ultra-fast reverse recovery diode. The simulation and experiment results are verified using MATLAB/Simulink software.
The real problems in diminution of power quality occurs due to the rapid growth of nonlinear load are leads to sudden decrease of source voltage for a few seconds i.e sag, swell, harmonics in source and load current, voltage unbalance etc. All these problems can be compensated by using Unified Power Quality Controller (UPQC) and the operation of UPQC depends upon the available voltage across capacitor present in dc link. If the capacitor voltage is maintained constant then it gives satisfactory performance. The proposed research is basically on designing of Photo Voltaic (PV) /Wind energy fed to the dc link capacitor of UPQC so as to maintain proper voltage across it and operate the UPQC for power quality analysis. The said model is simulated in Matlab and results are verified by using FFT analysis.The proposed PV/ Wind energy-UPQC is design in Matlab simulation for reduction of voltage sag, swell, interruption of voltage, harmonics in load current and compensation of active and reactive power.
In this paper a buck-boost dc-dc converter for pv application is proposed, which is mainly composed of a buck – boost converter, PV panel, load and a battery. Existing dc-dc converter can convert the power from the PV panel, but unfortunately the PV panel can only provide power when there is a high intensity of light. In order to provide power supply to the load without any interruption, buck-boost dc-dc converter is introduced. The power intermittency issue of PV panel can be overcome with the aid of a secondary supply which is in this case, the batter. The integration system between the primary and the secondary supply is controlled by a simple proposed control scheme. Battery act as a power in the low voltage side while PV panel is taking over in the high voltage side. Buck-boost converter is operated either is buck or boost mode according to the performance of the PV panel. This paper is presented the simple control scheme to decide the mode suitable for the buck and boost mode. Various conditions are simulated to verify the working operation of the buck-boost converter and to representing solar panel in real life. Simulation and experimental are carried out to verify the system.
Analysis of Fuel Cell Based Multilevel DC-DC Boost Converter for Induction MotorIJMTST Journal
In this paper new topologies and interleaving modulation concepts for multilevel DC-DC boost converter
enabling a significantly less loss and a reduced chip size of the power semiconductors are proposed. The
distributed generation (DG) systems based on the renewable energy sources have rapidly developed in
recent years. These DG systems are powered by micro sources such as fuel cells, photovoltaic (PV) systems,
and batteries. Fuel cells are considered to be one of the most promising sources of distributed energy because
of their high efficiency, low environmental impact and scalability. Non-isolated high step-up DC-DC
converters are required in the industrial applications. Many of these conventional DC–DC converters have the
disadvantages of operating at high duty-cycle, high switch voltage stress and high diode peak current. A
three-level step up converter is implemented to boost the fuel cell stack voltage of 96V to 340V. The proposed
converter consists a system of fuel cell based Multilevel DC-DC converter with PI controller is modeled and
simulated by using Matlab/Simulink.
Real Time Implementation of Variable Step Size Based P&O MPPT for PV Systems ...IJPEDS-IAES
Nowadays Solar energy is an important energy source due to the energy crisis and environment pollution. Maximum power point tracking (MPPT) algorithm improves the utilization efficiency of a photovoltaic systems. In this paper an improved P&O MPPT algorithm is developed and simulated using MATLAB / SIMULINK to control the DC/DC buck converter. The obtained simulink model is also verified using dspace tool. Both the simulated and experimental results are validated by also comparing them with conventional MPPT methods. The performance measures show the increase in the efficiency of PV system by the proposed model.
Basic MOSFET Based vs Couple-Coils Boost Converters for Photovoltaic GeneratorsIJPEDS-IAES
Considering the optimization of a photovoltaic system, several studies show the advantage in the choice of a distributed structure. For such structures small power converters such as the boosts and buck converters appear as most appropriate. We have analysed the efficiency of small power boost- converters especially dedicated for photovoltaic energy conversion systems working in the middle and high voltage ranges. The setup studied is a photovoltaic generator connected to an AC grid working in 230 Volts via an inverter. Moreover, we considered the possibility of multiple electrical energy sources as photovoltaic, wind systems in the same energy production system, which obliged an adaptive converter structure. We evaluated the losses in the various stages of a boost converter and point out the importance of the power MOSFET used as the commutation element. New transistors databases obtained from manufacturers show the nonlinear dependency between the resistance drain-source when passing, Rdson and the maximum rating voltage when the transistor is off, Vdsmax, for all transistor families. Thus nonlinear dependency induces a huge increase of losses with the voltage in the MOSFET, and as a direct consequence in the converter the more as Vdsmax is higher. In order to minimize losses of the converter we have designed and realized a new high efficiency version of a Step-Up structure based on a commutation element integrating a low Vdsmax voltage MOSFET and very low Rdson.
Презентація до мого майстер-класу у київському Freud House 21 жовтня 2014.
Трішки про те, як, я вірю, працює цей світ, про персональний продукт, цінність, просування та розвиток "бізнесу".
Головна думка презентації:
«Навіть, якщо ви працюєте «на когось», ви можете вже з цього моменту ставитись до роботи з «відповідальністю власного бізнесу» - своєї корпорації «Я»!
TOMADO CON FINES DOCENTES DE Escritores asociadosSon los padrinos de la Red de Talleres de Escritura Creativa. Son importantes escritores nacionales, con más de dos obras publicadas, que acompañan el proceso de los directores de taller al tiempo que guían a los participantes y los nutren con su propia experiencia.Vínculos relacionadosVer Imagen InformaciónAntonio García Ángel Ver Imagen InformaciónAntonio Ungar Ver Imagen InformaciónBeatriz Helena RobledoVer Imagen InformaciónClaudia Arroyave Ver Imagen InformaciónCristóbal Peláez González Ver Imagen InformaciónCristian ValenciaVer Imagen InformaciónEnrique Serrano Ver Imagen InformaciónFernando Quiroz Ver Imagen InformaciónHarold Kremer MartínezVer Imagen InformaciónHugo Chaparro Valderrama Ver Imagen InformaciónIrene Vasco Ver Imagen InformaciónJuan Diego MejíaVer Imagen InformaciónJulio Cesar Londoño Ver Imagen InformaciónLucía Estrada Ver Imagen InformaciónMario MendozaVer Imagen InformaciónNahum Montt Ver Imagen InformaciónOctavio Escobar Ver Imagen InformaciónPablo MontoyaVer Imagen InformaciónPedro Arturo Estrada Ver Imagen InformaciónPilar Lozano Ver Imagen InformaciónPilar QuintanaVer Imagen InformaciónRoberto Burgos Cantor Ver Imagen InformaciónRoberto Rubiano Ver Imagen InformaciónSamuel VásquezVer Imagen InformaciónSergio Álvarez Ver Imagen InformaciónTim Keppel
Matthias Weber, Образование взрослых в Восточной Германии на примере земли Са...Alianta INFONET
Matthias Weber, Образование взрослых в Восточной Германии на примере земли Саксония 20 лет спустя после воссоединения Германии ,
ІІІ Фестываль нефармальнай адукацыі, Minsk, 9.X.2010
Performance Metrics for your Build Pipeline - presented at Vienna WebPerf Oct...Andreas Grabner
Software Performance Metrics that you should look at throughout your Build Pipeline and not just when your app crashes in productiong.
Find performance and scalability problems as soon as executing your first Unit Test. Simply focus on metrics such as #SQLs, #LogMessages, #Objects on Heap, ...
Communication Performance Over A Gigabit Ethernet NetworkIJERA Editor
A present computing imposes heavy demands on the optical communication network. Gigabit Ethernet technology can provide the required bandwidth to meet these demands. However, it has also involve the communication Impediment to progress from network media to TCP(Transfer control protocol) processing. In this paper, present an overview of Gigabit per second Ethernet technology and study the end-to-end Gigabit Ethernet communication bandwidth and retrieval time. Performance graphs are collected using NetPipe in this clearly show the performance characteristics of TCP/IP over Gigabit Ethernet. These indicate the impact of a number of factors such as processor speeds, network adaptors, versions of the Linux Kernel or opnet softwar and device drivers, and TCP/IP(Internet protocol) tuning on the performance of Gigabit Ethernet between two Pentium II/350 PCs. Among the important conclusions are the marked superiority of the 2.1.121 and later development kernels and 2.2.x production kernels of Linux or opnet softwar used and that the ability to increase the MTU(maximum transmission unit) Further than the Ethernet standard of 1500 could significantly enhance the throughput reachable.
The performance of PV panel is very much dependent on the amount of sun light as well as the temperature of the surrounding environment which normally hard to be predicted. The use of PV emulator in the investigation of solar inverter especially at a lab scale platform helps to mitigate the inconsistency factors due to this uncontrollable variation. This work discussed on the design and development of a PV emulator for the grid-connected quasi-Z-source inverter which has different topology and control method compared to the conventional voltage source inverter. The I-V characteristics of the PV panel is modelled from the commercially available product and through circuit analysis the relation between capacitor voltage control and the PV terminal voltage is established, thus realizing the MPPT operation. Results from both simulation and experimental verification demonstrated that the PV emulator successfully able to produce power for the inverter according to the requirement.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This paper presents a circuit configuration of five-level PWM voltage-source inverter developed from the three-level H-bridge inverter using only a single DC input power source. In the proposed five-level inverter, an auxiliary circuits working as the voltage balancing circuits of the inverter’s DC capacitors is presented. The auxiliary circuits work to keep stable DC capacitor voltages of the inverter, and also to reduce the capacitor size of the inverter. The unique point of the proposed balancing circuits is that it needs only a single voltage sensor to control the voltages of the two capacitors in the inverter. Moreover, a minimum number the inverter’s switching devices is also an important feature of the proposed inverter topology. A simple proportional integral controller is applied to control the voltage of the DC capacitors. The proposed topology is tested through computer simulation using PSIM software. Laboratory experimental tests were also conducted to verify the proposed inverter circuits. The computer simulation and experimental test results showed that the proposed balancing circuits works properly keeping stable voltages across the two DC capacitors of the inverter using only a single voltage sensor. The inverter also works well to synthesize a five-level PWM voltage waveform with sinusoidal load current.
Incremental Conductance MPPT Algorithm for PV System Implemented Using DC-DC ...IJERA Editor
The two basic topologies of switch mode DC-DC converters (Buck and Boost) are analyzed with a view of their use in PV (photovoltaic) systems, as the photovoltaic generator exhibits non-linear characteristics due to the change in environmental condition and load variation. As the efficiency of PV panels is low it becomes mandatory to extract maximum power from the PV panel at a given period of time. Several MPPT algorithms with different types of converters are being proposed for extracting maximum power from the PV panel. It is found that the nature of load plays an important role in the choice of topology. This paper investigates the implementation issues of Incremental Conductance method with Buck and Boost Converters. Mathematical analysis and desirable steady-state operating point of the converters are derived to give satisfactory maximum power point tracking operation.
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.
Application ofBoost Inverter to Multi Input PV systemIJERA Editor
With the shortage of the energy and ever increasing of the oil price, research on the renewable and green energy
sources, especially the solar arrays and the fuel cells, becomes more and more important. How to achieve high
step- up and high efficiency DC/DC converters is the major consideration in the renewable power applications
due to the low voltage of PV arrays and fuel cells. The conventional boost converters increase the harmonics
rate and add an extra stage of power conversion. This paper proposes a boost dc-ac inverter that can invert and
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power panels and is simulated using Simulink. The output results of the boost inverter are worthy promising.
Energy Storage Management in Grid Connected Solar Photovoltaic SystemIJERA Editor
The penetration of renewable sources in the power system network in the power system has been increasing in the recent years. One of the solutions being proposed to improve the reliability and performance of these systems is to integrate energy storage device into the power system network. This paper discusses the modeling of photo voltaic and status of the storage device such as lead acid battery for better energy management in the system. The energy management for the grid connected system was performed by the dynamic switching process.
Photovoltaic System with SEPIC Converter Controlled by the Fuzzy LogicIAES-IJPEDS
In this work, a fuzzy logic controller is used to control the output voltage of a
photovoltaic system with a DC-DC converter; type Single Ended Primary
Inductor Converter (SEPIC). The system is designed for 210 W solar
photovoltaic (SCHOTT 210) panel and to feed an average demand of 78 W.
This system includes solar panels, SEPIC converter and fuzzy logic
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In this paper the multicarrier pulse width modulation (MCPWM) with multi value DC voltage source multilevel inverter is presented. These MLI’s are suitable in high voltage & high power application due to their ability to synthesize waveforms with better harmonic spectrum. Seven level inverter is simulated using MATLAB/Simulink. The use of Photovoltaic Cell as a DC source for the multilevel Inverter is proposed here.
Grid tied photovoltaic (PV) system is an operation mode of PV system working together with utility power supply to provide power to the power load. Conventionally, transformer is used together with the power inverter. The power transformer works as galvanic insolation amongst PV system and power grid. It works also to raise the voltage of power inverter. However, use of transformer will add system complexity, price, weight and size of the entire system. Transformer-less system is an alternative to make the system simpler and more practical in use. The paper discusses performance of transformer-less grid tied PV systems using diode clamped and neutral point shorted inverters. Effects of transformer elimination to the feat of the grid tied PV system especially harmonics content and leakage current of PV system were examined and analyzed. The performance was also compared with the traditional system using H-bridge inverter. The leakage currents did not flow in the system applying diode clamped inverter, and neutral point shorted inverter. In case of harmonics content, the diode clamped inverter injected less harmonics components than the neutral point shorted inverter. The neutral point shorted provides a simpler inverter circuit in the transformerless systems.
Parallel Operation of Current-Source Inverter for Low-Voltage High-Current Gr...IJECEIAES
Solar energy is very potential to be developed in a tropical country such as in Indonesia. This energy source is eco-friendly because it can eliminate air pollution such as caused by conventional fossil fuels. This research article presents analysis results of a novel grid-connected photovoltaic system using low-voltage high-current system. The electrical energy produced by the photovoltaic system was sent into the electrical power grid using two or more H-bridge current source inverters operated in parallel. The proposed system is very suitable for large size photovoltaic system because of its some merits. The inverter circuits work generating sinusoidal output currents and controlling the power delivered into the grid. The test results of the new system showed that the system worked properly as interface between photovoltaic system and the electrical grid delivering high ac current with low harmonic distortion.
A Novel Approach on Photovoltaic Technologies for Power Injection in Grid Usi...IJERA Editor
The paper presents the simulation of the Solar Photovoltaic module using Matlab Simulink. This model is based on mathematical equations and is described through an equivalent circuit including a photocurrent source, a diode, a series resistor and a shunt resistor. This paper presents integration of the grid distribution network in Indian scenario with solar power technology to meet the additional electrical energy demand of urban as well as rural sectors which are both rapidly expanding. First of all the data of a real life power plant having 24V, 230W Power PV module has been compared and analyzed with that of matlab program output for identical module and it has been find out that a variation in temperature affects the parameters values as well as the performance of the solar module. After the above analysis the design and Simulink implementation for single phase power grid connected PV system has been done. The system includes the PV array model, the integration of the MPPT with boost dc converter , dc to ac inverter, single phase series load connected to ac grid. It is demonstrated that the model works well at different temperature conditions and predicting the General behavior of single-phase grid- connected PV systems .
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Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
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Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
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Z - Source Multi Level Inverter Based PV Generation System
1. T. Lakhmi kanth et al. Int. Journal of Engineering Research and Applications www.ijera.com
ISSN : 2248-9622, Vol. 4, Issue 9( Version 6), September 2014, pp.137-141
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Z - Source Multi Level Inverter Based PV Generation System T. Lakhmi kanth1, CH. Rambabu2, R. Punyavathi3 1 MTECH student, Electrical & electronics engineering, VVIT, AP, INDIA 2 Associate professor, Electrical & electronics engineering, VVIT, AP, INDIA 3MTECH student, Electrical & electronics engineering, KL University, vaddeswaram, AP, INDIA Abstract In this paper a novel technique of Z-Source multilevel Inverter based PV Generation system is implemented and simulated using MATLAB-Simulink simulation software. The Photovoltaic cells are healthier option for converting solar energy into electricity. Due to high capital cost and low efficiency PV cells have not yet been a fully smart choice for electricity users. To enhance the performance of the system, Z-Source multi level inverter can be used in place of conventional Voltage Source Inverter (VSI) in Solar Power Generation System. The PV cell model is developed using circuit mathematical equations. The Z-Source multilevel inverter is modeled to realize boosted DC to AC conversion (inversion) with low THD. Outcome shows that the energy conversion efficiency of ZSMLI is a lot improved as compared to conventional voltage Source Inverter (VSI). By doing FFT analysis we can know the total THD. Key words: PV Panel; Z-MLI; MPPT; PWM Inverter.
I. INTRODUCTION
The Solar Energy Source has attracted the attention for electrical power generation because the generated power is environment friendly, noiseless, has longer life with little maintenance, highly mobile and portable because of light weight. Advancement is going on in solar power generation technologies day by day. A simple way to increase the output voltage of Solar Energy sources is to connect a number of Solar Panel in series and use a conventional voltage source inverter. However, this series configuration has some drawback, such as low reliability and low efficiency. For analyzing the performance of the Solar Power Generation System a simulation model has been developed using basic circuit equations of photovoltaic (PV) cells including the effects of solar irradiation and temperature changes. This model was tested using a directly coupled DC load as well as AC load using IGBT based inverter [3]. For the better accuracy at low irradiation level, a two diode model to represent a PV cell has been proposed. This topology needs additional iteration method for the calculation of series and parallel resistance [4]. A simple PV array modeling has also been presented with parallel resistance [5].
Most of the investigations in the literature for solar energy system have adopted the topologies and control algorithm for DC-AC Inverter to improve the conversion efficiency. A step-up transformer can be utilized at line frequency to boost the voltage after the inverter. However, this solution has several disadvantages, such as huge size, loud acoustic noise, and relatively high cost [6]. The three-phase multi- level inverters can also be employed to interface the output of several Solar Energy sources to the load [7]. Although the multi-level inverters are effective for this application, the added complexity of the circuit, the additional components, reduce both the overall efficiency and reliability of the system, and may raise the on the whole price of interface. Another option is the z-source inverter that can be applied for solar energy systems. The z-source inverter has the capability of boosting and inverting the dc voltage in a single-stage, with less no of switches in comparison with multi-level inverters and the two-stage topologies. The Z-source inverters and ultra capacitors based fuel cell system has been developed [8-10]. The harmonic study of Z-source inverter proves that it works more efficiently and has better performance as compared to traditional voltage and current source inverter [11]. The transient Modeling and Analysis of advanced Pulse-Width Modulated Z-Source Inverter has been presented. For improving the performance and efficiency of the Photovoltaic system the Z-source inverter can also be employed [12-14]. In this paper a simulation model of photovoltaic system feeding AC load is modeled using simulink toolbox. For DC to AC energy conversion the Z- Source inverter is used, which also acts as a boost inverter. The system is analyzed for linear resistive/R-L and nonlinear rectifier load. A comparison study of solar power generation using conventional PWM inverter and Z-Source inverter has also been performed.
RESEARCH ARTICLE OPEN ACCESS
2. T. Lakhmi kanth et al. Int. Journal of Engineering Research and Applications www.ijera.com
ISSN : 2248-9622, Vol. 4, Issue 9( Version 6), September 2014, pp.137-141
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II. SYSTEM CONFIGURATION
Fig. 1a shows the block diagram of conventional
Solar Power Generation System using the PWM
voltage source inverter. The PV Panel or Array is
defined as the group of PV cells electrically
connected in series or parallel to generate the
required voltage and current. Voltage or current
generated by PV Panel is DC quantity. A Filter is
connected to reduce the ripples caused by the
temperature and irradiation variations. This filter is
also capable of maintaining stable voltage at the load
side.
Fig- 1a: Conventional Solar Power Generation
System
The Z-Source Inverter based Solar Power
Generation System consists of PV panel, filter, Z-Source
Inverter (ZSI), DC-DC boost converter. Fig.
1b shows the block diagram of the system Solar
Power Generation System using the ZSI.
Fig- 1b: Proposed Z-Source based MLI Solar Power
Generation System
For feeding the 3-phase load, ZSI is employed to
convert the DC voltage into pure sinusoidal AC
voltage waveform. The ZSI is a latest topology for
the successful electrical power conversion that can
buck or boost the input voltage/current with unique
single circuit, which is not possible in conventional
PWM voltage/current source inverter. An additional
isolation transformer is connected between the VSI
and load. This transformer has higher cost and
weight. In the developed system, ZSI is implemented
for DC-AC conversion and acts as a boost inverter
for obtaining the desired voltage level and there is no
need of transformer. The pure sinusoidal AC output
voltage of the ZSI is fed to the consumer load.
III. MATHEMATICAL MODELING
The Solar Power Generation System using the Z-Source
inverter can be mathematically modeled as:
3.1. PV Panel Modeling
The PV cells are usually represented by a
simplified equivalent circuit model as shown in the
fig. 2.
Fig. 2. Equivalent Circuit of PV Cell
The PV cell output voltage, which is function of
photocurrent depending on the temperature and solar
irradiation level, is explained as below:
If the temperature and solar irradiation levels change,
the V & I yields the PV array will follow this change.
The effect of variable ambient temperature Ta is
represented by the temperature coefficients CTV and
CTI for the cell output voltage and cell photocurrent
respectively as:
Where, βT= 0.004 and αT=0.06 for the cell used. The
ambient temperature (Ta) throughout the cell testing
is approximates to 200 Centigrade. The change in the
temperature is represented by TX. This will be
responsible for the change in the voltage generated
by the PV Panel.
A change in solar irradiation level causes a
change in the cell photocurrent and operating
temperature, which affects the cell output voltage.
The change in the operating temperature and in the
photocurrent due to variation in the solar irradiation
level can be expressed by the correction factors i.e.
3. T. Lakhmi kanth et al. Int. Journal of Engineering Research and Applications www.ijera.com
ISSN : 2248-9622, Vol. 4, Issue 9( Version 6), September 2014, pp.137-141
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CRV and CRI for changes in cell output voltage V and PV currents are as;
Where, SC is the reference solar irradiation level during the cell testing. Sx is the new level of solar irradiation. The new values of the cell output voltage VCX and photocurrent I Phx for the new temperature Tx and solar irradiation Sx can be given as:
3.2. Z-Source Inverter Modeling The equivalent circuit arrangement of Z-Source Inverter Bridge is shown in the fig. 3. Assuming that L1 = L2 and C1 = C2 for the symmetrical Z-source network. Hence, the voltages across capacitors and inductors are as follows [8]: VC1 = VC2 = VC and VL1 = VL2 = VL (9)
Fig- 3: Z-source Inverter Bridge During the shoot - through zero state for an interval (T0) during a switching cycle (TZ), VL=VC, Vd = 2VC, V0=0 (10) Now consider that the inverter bridge is in one of the eight non-shoot-through states for an interval of T1, during the switching cycle, TZ VL=V0 – VC, V0= VC – VL = 2VC –Vpv (11) Where Vpv is the output DC voltage of PV panel and TZ = T0+T1. The average voltage of the inductors over one switching period T should be zero in steady state. From Eq.10 and Eq.11 voltage across inductor and capacitor are obtained as:
VL= [T0 VC + T1 (Vpv – VC)] / TZ =0 (12)
VC / Vpv = T1/ (T1- T0) (13) Similarly, the average DC-link voltage across the inverter bridge can be found as follows: V0 = [T0 * 0 + T1 (2VC –Vpv)] / TZ = [T1/ (T1- T0)] Vpv (14) The peak DC-link voltage across the inverter bridge is expressed in eqn.11 can be rewritten as: Vo= VC – VL = 2VC –Vpv = [TZ/ (T1- T0)] = B.Vpv (15) Where, B = TZ/ (T1- T0) = 1/ (1-2T0 /TZ) ≥1 (16) The DC-link voltage is the boost factor resulting from the shoot-through zero state. The peak DC-link voltage Vo is the equivalent DC-link voltage of the inverter. On the other side, the output voltage from the inverter can be presented as: Vac= M Vo/2 (17) Where, M is the modulation Index. Using Eq. 15 and Eq. (17) can be further expressed as: Vac= M* B* Vpv /2 (18) Eqn. 17 shows that the output voltage can be stepped up and down by choosing an appropriate buck–boost factor BB, BBF = M* B= (0≈∞) (19) from eqn. 9, eqn. 13 and eqn. 16, the capacitor voltage can express as:
VC1= VC2= VC = [1-(T0 / TZ)] /[1-(2T0 / TZ)] Vpv (20) The buck–boost factor BBF is determined by the modulation index M and boost factor B.
IV. MPPT TECHNIQUE
A typical solar panel converts only 30% to 40% of the incident solar irradiation into electrical energy. Hence, the efficiency of the PV Panel is about 15- 20%. The only alternative to improve the efficiency of PV panel is Maximum power point tracking technique. Using these MPPT techniques, the PV array is controlled to generate the maximum power at any particular environment condition. There are different techniques used to track the maximum power point. Few of the most popular techniques are: 1. Perturb and observe (hill climbing method) 2. Incremental Conductance method 3. Fractional short circuit current
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4. Fractional open circuit voltage 5. Neural networks 6. Fuzzy logic In the proposed system Incremental Conductance method is chosen for our consideration. In this method, the system measures incremental variations in array V & I to find the effect of a change in voltage. This method requires more calculations in the regulator, but can get altering circumstances more fastly than the perturb and observe method (P&O). Like the P&O algorithm, it can produce oscillations in power. This method consumes the incremental conductance (dI/dV) of the photovoltaic array to calculate the sign of the change in power with respect to voltage (dP/dV). The incremental conductance method computes the maximum power point by comparison of the incremental conductance (ΔI/ΔV) with the array conductance (I/V). When the incremental conductance is nilling, the output of the voltage is the MPP voltage. The system controller maintains this voltage until the irradiation changes and the process is repeated.
V. MULTI LEVEL INVERTER
The modified single phase five-level inverter circuit diagram is shown in Fig 4. This is a five level fly back capacitor multi level invereter. By using this type of multi level inverter we can reduce the THD of the system, boost operation also can be done by Z source network before the Multi level inverter.
Fig- 4: Single phase five level flying capacitor MLI
Fig-5: Simulink diagram for PV based z source multi level inverter
Fig- 6: Ideal five level output voltage waveform
VI. SIMULATION RESULTS
The below figure will gives you the Simulation results of a Z- source MLI output with five levels & low Total harmonic distortion value. THD can be calculated by using FFT analysis in MATLAB.
Fig-7: Five level output voltage with THD
VII. CONCUSION
This paper proposes a simulation model for Z- source multi level inverter based solar power generation system. The Z-source multi level inverter is used in place of conventional voltage source inverter. The Z-source multi level inverter provides exceptional features that cannot be seen in the conventional DC-AC inverter. The conventional voltage source inverter needs a step up or step down
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transformer to meet the supply requirements. The Z- source inverters do not require the additional transformer because it can act as either buck or boost inverter as per the requirement. Hence it can produce any desired output AC voltage. After the analysis of simulation results it is concluded that system is able to supply the linear and nonlinear resistive/R-L load efficiently. The proposed system is having low cost, small size, reduced weight, more efficient and reliable as compared to conventional topology for energy conversion. After the analysis it is concluded that the ZSI has the better performance as compared to conventional VSI because it can produce any desired output ac voltage, even greater than line voltage, reduces harmonic currents. REFERENCES [1] R. O. Caceres and I. Barbi, ―A boost dc-ac converter: analysis, design, and experimentation,‖ The IEEE Transaction on Power Electronics, Vol. 14, No. 1, pp. 134– 141, Jan. 1999. [2] W. Chien-Ming, ―A novel single-stage full- bridge buck-boost inverter,‖ IEEE Transaction Power Electronics, Vol. 19, No. 1, pp. 150–159, Jan. 2004. [3] I.H. Altas, A.M. Sharaf, ―A Photovoltaic Array Simulation Model for Matlab-Simulink GUI Environment‖, International Conference on Clean Electrical Power, pp. 341-345, July 2007. [4] IshaqueKashif, Salam Zainal and TaheriHamed, ―Accurate Matlab Simulink PV System Simulator Based on a Two-Diode Model‖, Journal of Power Electronics, Vol. 11, No. 2, Dec. 2010. [5] Islam, Aneek Department of Electrical and Electronics Engineering, United International University, Dhanmondi, Dhaka 1209, Bangladesh Chowdhury, Md.Iqbal Bahar [6] Yushan Liu ; Abu-Rub, H. ; Baoming Ge ; Fang Zheng Peng Applied Power Electronics Conference and Exposition (APEC),2014 Twenty-Ninth Annual IEEE .
BIOGRAPHIES
Mr. T. Lakshmi kanth born in 1990. He is pursuing MTECH (Power electronics & electric drives) degree in Electrical & electronics engineering in VVIT, Guntur. E-mail: lakshmikanth.tiramdasu@gmail.com
Mr.CH. Rambabu completed his B.E from Madras university, and M.E From ANNA university, total he had 10 years of experience and he is working in VVIT, Guntur as an Associate professor. E-mail: rams_babu2001@yahoo.com
Mrs. R. Punyavathi was born in 1987. She received her MTECH (Power Electronics and Power Systems) degree in Electrical and Electronics Engineering from K.L. University. Presently she is working as assistant professor in K.L. University; Vaddeswaram. She is guiding both undergraduate and post graduate student projects. Her area of interest includes Power Electronics and Drives. E-mail:raminenipunyavathi@gmail.com