IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
This paper provides a new approach to reducing high-order harmonics in 400 Hz inverter using a three-level neutral-point clamped (NPC) converter. A voltage control loop using the harmonic compensation combined with NPC clamping diode control technology. The capacitor voltage imbalance also causes harmonics in the output voltage. For 400 Hz inverter, maintain a balanced voltage between the two input (direct current) (DC) capacitors is difficult because the pulse width modulation (PWM) modulation frequency ratio is low compared to the frequency of the output voltage. A method of determining the current flowing into the capacitor to control the voltage on the two balanced capacitors to ensure fast response reversal is also given in this paper. The combination of a high-harmonic resonator controller and a neutral-point voltage controller working together on the 400 Hz NPC inverter structure is given in this paper.
The electrical and environmental parameters of polymer solar cells (PSC) provide important information on their performance. In the present article we study the influence of temperature on the voltage-current (I-V) characteristic at different temperatures from 10 °C to 90 °C, and important parameters like bandgap energy Eg, and the energy conversion efficiency η. The one-diode electrical model, normally used for semiconductor cells, has been tested and validated for the polemeral junction. The PSC used in our study are formed by the poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM). Our technique is based on the combination of two steps; the first use the Least Mean Squares (LMS) method while the second use the Newton-Raphson algorithm. The found results are compared to other recently published works, they show that the developed approach is very accurate. This precision is proved by the minimal values of statistical errors (RMSE) and the good agreement between both the experimental data and the I-V simulated curves. The obtained results show a clear and a monotonic dependence of the cell efficiency on the studied parameters.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
This paper provides a new approach to reducing high-order harmonics in 400 Hz inverter using a three-level neutral-point clamped (NPC) converter. A voltage control loop using the harmonic compensation combined with NPC clamping diode control technology. The capacitor voltage imbalance also causes harmonics in the output voltage. For 400 Hz inverter, maintain a balanced voltage between the two input (direct current) (DC) capacitors is difficult because the pulse width modulation (PWM) modulation frequency ratio is low compared to the frequency of the output voltage. A method of determining the current flowing into the capacitor to control the voltage on the two balanced capacitors to ensure fast response reversal is also given in this paper. The combination of a high-harmonic resonator controller and a neutral-point voltage controller working together on the 400 Hz NPC inverter structure is given in this paper.
The electrical and environmental parameters of polymer solar cells (PSC) provide important information on their performance. In the present article we study the influence of temperature on the voltage-current (I-V) characteristic at different temperatures from 10 °C to 90 °C, and important parameters like bandgap energy Eg, and the energy conversion efficiency η. The one-diode electrical model, normally used for semiconductor cells, has been tested and validated for the polemeral junction. The PSC used in our study are formed by the poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM). Our technique is based on the combination of two steps; the first use the Least Mean Squares (LMS) method while the second use the Newton-Raphson algorithm. The found results are compared to other recently published works, they show that the developed approach is very accurate. This precision is proved by the minimal values of statistical errors (RMSE) and the good agreement between both the experimental data and the I-V simulated curves. The obtained results show a clear and a monotonic dependence of the cell efficiency on the studied parameters.
Novel technique in charactarizing a pv module using pulse width modulatoreSAT Journals
Abstract The fabrication and characterization of PV modules are always done under standard test conditions (STC). However, The condition of operation are often far from thisstandard conditions. As a result, developing a characterization circuit is considered as a point of interest for researchers.This paper presents a new methodology in characterizing a PV module using an electronic load circuit. The circuit is implemented using a power MOSFET driven by a pulse width modulator (PWM) developed by LABVIEW. The system is tested and its results are validated by comparing it with simulation results performed by Comsol Multiphysics and Matlab. The system shows high accuracy with respect to the previous published work with lower cost and higher simplicity. Keywords: Photovoltaic, Characterization, Electronic load, and Pulse width modulation (PWM)…
Modelling of fuzzy logic controller for variable step mppt in photovoltaic sy...eSAT Journals
Abstract
The output power of photovoltaic electrical systems is highly dynamic and non-linear in nature. In order to extract maximum power
from such systems, maximum power point tracking (MPPT) technique is required. MPPT techniques with variable step-size of
perturbation track the maximum power point (MPP) with more efficiency. In this paper, a model of a fuzzy logic controller (FLC) for
determining the step-size of perturbation in duty-cycle of a photovoltaic electrical system to track MPP is presented. The model is
simulated in MATLAB/Simulink®.
Keywords: Maximum power point tracking, perturb and observe, boost converter, fuzzy logic control, membership
function, crisp universe, centre of area, pulse width modulation
A Comprehensive Analysis of Partial Shading Effect on Output Parameters of a ...IJECEIAES
One of the issues of grid-connected photovoltaic systems is the effect of the partial shading on the key parameters and performance of the system. In practice, a share of the entire PV panel may shadded because of the various reasons, inevitably. In this case, the key parameters of the system output are affected with respect to the shading extent and paradigm. In this paper, the effects of the various partial shading patterns on the ouput of the system are examined. This is performed by deriving relevant equations and appropriate modeling of the system and defining different scenarios. The analysis on the system performance is carried out on the dominant output parameters including panel voltage, panel power, and total harmonic distortion (THD) of the inverter. Also, the study considers the effect of using bypass diodes in the panels or not. Addintionally, to compare derived conclusions, the study is implementd on a practical system. The set up is made up of a 7-level multilevel inverter, a Z-source converter, and 1 kW lateral circuitry. The real world test results of the study demonstrate a negligible deviation compared to the simulation results.
A new bidirectional multilevel inverter topology with a high number of voltage levels with a very reduced number of power components is proposed in this paper. Only TEN power switches and four asymmetric DC voltage sources are used to generate 25 voltage levels in this new topology. The proposed multilevel converter is more suitable for e-mobility and photovoltaic applications where the overall energy source can be composed of a few units/associations of several basic source modules. Several benefits are provided by this new topology: Highly sinusoidal current and voltage waveforms, low Total Harmonic Distortion, very low switching losses, and minimum cost and size of the device. For optimum control of this 25-level voltage inverter, a special Modified Hybrid Modulation technique is performed. The proposed 25-level inverter is compared to various topologies published recently in terms of cost, the number of active power switches, clamped diodes, flying capacitors, DC floating capacitors, and the number of DC voltage sources. This comparison clearly shows that the proposed topology is cost-effective, compact, and very efficient. The effectiveness and the good performance of the proposed multilevel power converter (with and without PWM control) are verified and checked by computational simulations.
Modeling of solar array and analyze the current transientEditor Jacotech
Spacecraft bus voltage is regulated by power
conditioning unit using switching shunt voltage regulator having
solar array cells as the primary source of power. This source
switches between the bus loads and the shunt switch for fine
control of spacecraft bus voltage. The effect of solar array cell
capacitance [5][6] along with inductance and resistance of the
interface wires between solar cells and power conditioning
unit[1], generates damped sinusoidal currents superimposed on
the short circuit current of solar cell when shunted through
switch. The peak current stress on the shunt switch is to be
considered in the selection of shunt switch in power conditioning
unit. The analysis of current transients of shunt switch in PCU
considering actual spacecraft interface wire length by
illumination of solar panel (combination of series and parallel
solar cells) is difficult with hardware simulation. Software
simulation by modeling solar cell is carried out for a single string
(one parallel) in Pspice [6]. Since in spacecrafts number of
parallels and interface cable length are variable parameters the
analysis of current transients of shunt switch is carried out by
modeling solar array with the help of solar cell model[6] for the
actual spacecraft condition.
When the irradiance distribution over the photovoltaic panels is uniform, the pursuit of the maximum power point is not reached, which has allowed several researchers to use traditional MPPT techniques to solve this problem Among these techniques a PSO algorithm is used to have the maximum global power point (GMPPT) under partial shading. On the other hand, this one is not reliable vis-à-vis the pursuit of the MPPT. Therefore, in this paper we have treated another technique based on a new modified PSO algorithm so that the power can reach its maximum point. The PSO algorithm is based on the heuristic method which guarantees not only the obtaining of MPPT but also the simplicity of control and less expensive of the system. The results are obtained using MATLAB show that the proposed modified PSO algorithm performs better than conventional PSO and is robust to different partial shading models.
Alternating current (AC) electrical drives mainly require smaller current (or torque) ripples and lower total harmonic distortion (THD) of voltage for excellent drive performances. Normally, in practice, to achieve these requirements, the inverter needs to be operated at high switching frequency. By operating at high switching frequency, the size of filter can be reduced. However, the inverter which oftenly employs insulated gate bipolar transistor (IGBT) for high power applications cannot be operated at high switching frequency. This is because, the IGBT switching frequency cannot be operated above 50 kHz due to its thermal restrictions. This paper proposes an alternate switching strategy to enable the use of IGBT for operating the inverter at high switching frequency to improve THD performances. In this strategy, each IGBT in a group of switches in the modified inverter circuit will operate the switching frequency at one-fourth of the inverter switching frequency. The alternate switching is implemented using simple analog and digital integrated circuits.
This paper deals with an advanced design for a pump powered by solar energyto supply agricultural lands with water and also the maximum power point is used to extract the maximum value of the energy available inside the solar panels and comparing between techniques MPPT such as Incremental conductance, perturb & observe, fractional short current circuit, and fractional open voltage circuit to find the best technique among these. The solar system is designed with main parts: photovoltaic (PV) panel, direct current/direct current (DC/DC) converter, inverter, filter, and in addition, the battery is used to save energy in the event that there is an increased demand for energy and not to provide solar radiation, as well as saving energy in the case of generation more than demand. This work was done using the matrix laboratory (MATLAB) simulink program.
Electricity is a major source of energy for fast growing population and the use of nonrenewable source is harmful for our environment. This reason belongs to devastating of environment, so it is required to take immediate action to solve these problems which result the solar energy development. Production of a solar energy can be maximizing if we use solar follower. The major part of solar panels is microcontroller with arrangement of LDR sensor is used to follow the sun, where the sensors is less efficient to track the sun because of the low sensitivity of LDR. We are proposing a method to track sun more effetely with the help of both LDR sensors and image processing. This type of mechanism can track sun with the help of image processing software which combines both result of sensors and processed sun image to control the solar panel. The combination of both software and hardware can control thousands of solar panels in solar power plants.
A hybrid DC/DC/AC converter connected to the grid without a three-phase transformer is controlled. The decentralized control method is applied to the hybrid DC-DC converter such that the maximum power of PV flows to the grid side. This controller must charge and discharge the battery at the proper time. It must also regulate DC-link voltage. An additional advantage of the proposed control is that the three-phase inverter does not need a separate controller such as PWM and SPWM. A simple technique is used for creating the desired phase shift in the three-phase inverter, which makes the active and reactive power of the inverter controllable. A new configuration is also proposed to transmit and manage the generation power of PV. In this scheme, the battery and fuel cell are employed as an auxiliary source to manage the generation power of PV. Finally, a real-time simulation is performed to verify the effectiveness of the proposed controller and system by considering the real characteristics of PV and FC.
Direct current (DC) electronic load is a useful equipment for testing the electrical system. It can emulate various load at a high rating. The electronic load requires a power converter to operate and a linear regulator is a common option. Nonetheless, it is hard to control due to the temperature variation. This paper proposed a DC electronic load using the boost converter. The proposed electronic load operates in the continuous current mode and control using the integral controller. The electronic load using the boost converter is compared with the electronic load using the linear regulator. The results show that the boost converter able to operate as an electronic load with an error lower than 0.5% and response time lower than 13 ms.
New Structure for Photovoltaic SystemApplications with Maximum Power Point Tr...IAES-IJPEDS
This paper recommendes a new structure for photovoltaicsystems with a new inverter topology. A quasi-Z-source DC-DC converter with capability of dividing its output voltage to the same voltages and tracking maximum power point is proposed. The proportional-integral incremental conductance method is used for maximum power point tracking. The new recommended inverter topology is linked to quasi-Z-source converter for transferring power. For triggering inverter switches, alternate phase opposition disposition switching technique is utilized. A comparison is drawn between suggested multilevel inverter topology and other conventional multilevel inverter topologies. Description of proposed structure along with detailed simulation results that verify its feasibility are given to demonstrate the availability of the proposed system by MATLAB/Simulink software.
Development and Analysis of Fuzzy Control for MPPT Based Photovoltaic SystemIJERD Editor
In PV system control of Power electronics converters are very essential for the efficient utilization
of the solar System. This paper proposes modified Perturb & Observe Maximum power point tracking (MPPT)
with a fuzzy controller for DC-DC boost converter control in Photovoltaic system under shading and varying
atmospheric conditions. This paper proposes a different approach for MPPT of PV system so as to obtain
maximum power from PV system. In conventional methods, tracking power contains oscillation in the output
power. The Simulation and modeling of Photovoltaic system along with proposed algorithm are done using
MATLAB/SIMLINK software. Form Simulation results shows that P & O based fuzzy controller algorithm is
transient state is fast, less fluctuations and smooth in signal of generated power.
The impact of channel fin width on electrical characteristics of Si-FinFET IJECEIAES
This paper studies the impact of fin width of channel on temperature and electrical characteristics of fin field-effect transistor (FinFET). The simulation tool multi-gate field effect transistor (MuGFET) has been used to examine the FinFET characteristics. Transfer characteristics with various temperatures and channel fin width (W F =5, 10, 20, 40, and 80 nm) are at first simulated in this study. The results show that the increasing of environmental temperature tends to increase threshold voltage, while the subthreshold swing (SS) and drain-induced barrier lowering (DIBL) rise with rising working temperature. Also, the threshold voltage decreases with increasing channel fin width of transistor, while the SS and DIBL increase with increasing channel fin width of transistor, at minimum channel fin width, the SS is very near to the best and ideal then its value grows and going far from the ideal value with increasing channel fin width. So, according to these conditions, the minimum value as possible of fin width is the preferable one for FinFET with better electrical characteristics.
An optimum location of on-grid bifacial based photovoltaic system in Iraq IJECEIAES
Bifacial photovoltaic (PV) module can gain 30% more energy compared to monofacial if a suitable location were chosen. Iraq (a Middle East country) has a variable irradiation level according to its geographic coordinates, thus, the performance of PV systems differs. This paper an array (17 series, 13 parallel) was chosen to produce 100 kWp for an on-grid PV system. It investigates the PV system in three cities in Iraq (Mosul, Baghdad, and Basrah). Effect of albedo factor, high and pitch of the bifacial module on energy yield have been studied using PVsyst (software). It has been found that the effect is less for a pitch greater than 6 m. The energy gained from bifacial and monofacial PV system module in these cities shows that Mosul is the most suitable for installing both PV systems followed by Baghdad and lastly Basrah. However, in Basrah, the bifacial gain is 12% higher in the energy than monofacial as irradiation there is higher than the other locations, especially for elevation above 1.5 m. Moreover, the cost of bifacial array is 7.23% higher than monofacial, but this additional cost is acceptable since the bifacial gain is about 11.3% higher energy compared to the monofacial.
Improving efficiency of Photovoltaic System with Neural Network Based MPPT Co...IJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
Novel technique in charactarizing a pv module using pulse width modulatoreSAT Journals
Abstract The fabrication and characterization of PV modules are always done under standard test conditions (STC). However, The condition of operation are often far from thisstandard conditions. As a result, developing a characterization circuit is considered as a point of interest for researchers.This paper presents a new methodology in characterizing a PV module using an electronic load circuit. The circuit is implemented using a power MOSFET driven by a pulse width modulator (PWM) developed by LABVIEW. The system is tested and its results are validated by comparing it with simulation results performed by Comsol Multiphysics and Matlab. The system shows high accuracy with respect to the previous published work with lower cost and higher simplicity. Keywords: Photovoltaic, Characterization, Electronic load, and Pulse width modulation (PWM)…
Modelling of fuzzy logic controller for variable step mppt in photovoltaic sy...eSAT Journals
Abstract
The output power of photovoltaic electrical systems is highly dynamic and non-linear in nature. In order to extract maximum power
from such systems, maximum power point tracking (MPPT) technique is required. MPPT techniques with variable step-size of
perturbation track the maximum power point (MPP) with more efficiency. In this paper, a model of a fuzzy logic controller (FLC) for
determining the step-size of perturbation in duty-cycle of a photovoltaic electrical system to track MPP is presented. The model is
simulated in MATLAB/Simulink®.
Keywords: Maximum power point tracking, perturb and observe, boost converter, fuzzy logic control, membership
function, crisp universe, centre of area, pulse width modulation
A Comprehensive Analysis of Partial Shading Effect on Output Parameters of a ...IJECEIAES
One of the issues of grid-connected photovoltaic systems is the effect of the partial shading on the key parameters and performance of the system. In practice, a share of the entire PV panel may shadded because of the various reasons, inevitably. In this case, the key parameters of the system output are affected with respect to the shading extent and paradigm. In this paper, the effects of the various partial shading patterns on the ouput of the system are examined. This is performed by deriving relevant equations and appropriate modeling of the system and defining different scenarios. The analysis on the system performance is carried out on the dominant output parameters including panel voltage, panel power, and total harmonic distortion (THD) of the inverter. Also, the study considers the effect of using bypass diodes in the panels or not. Addintionally, to compare derived conclusions, the study is implementd on a practical system. The set up is made up of a 7-level multilevel inverter, a Z-source converter, and 1 kW lateral circuitry. The real world test results of the study demonstrate a negligible deviation compared to the simulation results.
A new bidirectional multilevel inverter topology with a high number of voltage levels with a very reduced number of power components is proposed in this paper. Only TEN power switches and four asymmetric DC voltage sources are used to generate 25 voltage levels in this new topology. The proposed multilevel converter is more suitable for e-mobility and photovoltaic applications where the overall energy source can be composed of a few units/associations of several basic source modules. Several benefits are provided by this new topology: Highly sinusoidal current and voltage waveforms, low Total Harmonic Distortion, very low switching losses, and minimum cost and size of the device. For optimum control of this 25-level voltage inverter, a special Modified Hybrid Modulation technique is performed. The proposed 25-level inverter is compared to various topologies published recently in terms of cost, the number of active power switches, clamped diodes, flying capacitors, DC floating capacitors, and the number of DC voltage sources. This comparison clearly shows that the proposed topology is cost-effective, compact, and very efficient. The effectiveness and the good performance of the proposed multilevel power converter (with and without PWM control) are verified and checked by computational simulations.
Modeling of solar array and analyze the current transientEditor Jacotech
Spacecraft bus voltage is regulated by power
conditioning unit using switching shunt voltage regulator having
solar array cells as the primary source of power. This source
switches between the bus loads and the shunt switch for fine
control of spacecraft bus voltage. The effect of solar array cell
capacitance [5][6] along with inductance and resistance of the
interface wires between solar cells and power conditioning
unit[1], generates damped sinusoidal currents superimposed on
the short circuit current of solar cell when shunted through
switch. The peak current stress on the shunt switch is to be
considered in the selection of shunt switch in power conditioning
unit. The analysis of current transients of shunt switch in PCU
considering actual spacecraft interface wire length by
illumination of solar panel (combination of series and parallel
solar cells) is difficult with hardware simulation. Software
simulation by modeling solar cell is carried out for a single string
(one parallel) in Pspice [6]. Since in spacecrafts number of
parallels and interface cable length are variable parameters the
analysis of current transients of shunt switch is carried out by
modeling solar array with the help of solar cell model[6] for the
actual spacecraft condition.
When the irradiance distribution over the photovoltaic panels is uniform, the pursuit of the maximum power point is not reached, which has allowed several researchers to use traditional MPPT techniques to solve this problem Among these techniques a PSO algorithm is used to have the maximum global power point (GMPPT) under partial shading. On the other hand, this one is not reliable vis-à-vis the pursuit of the MPPT. Therefore, in this paper we have treated another technique based on a new modified PSO algorithm so that the power can reach its maximum point. The PSO algorithm is based on the heuristic method which guarantees not only the obtaining of MPPT but also the simplicity of control and less expensive of the system. The results are obtained using MATLAB show that the proposed modified PSO algorithm performs better than conventional PSO and is robust to different partial shading models.
Alternating current (AC) electrical drives mainly require smaller current (or torque) ripples and lower total harmonic distortion (THD) of voltage for excellent drive performances. Normally, in practice, to achieve these requirements, the inverter needs to be operated at high switching frequency. By operating at high switching frequency, the size of filter can be reduced. However, the inverter which oftenly employs insulated gate bipolar transistor (IGBT) for high power applications cannot be operated at high switching frequency. This is because, the IGBT switching frequency cannot be operated above 50 kHz due to its thermal restrictions. This paper proposes an alternate switching strategy to enable the use of IGBT for operating the inverter at high switching frequency to improve THD performances. In this strategy, each IGBT in a group of switches in the modified inverter circuit will operate the switching frequency at one-fourth of the inverter switching frequency. The alternate switching is implemented using simple analog and digital integrated circuits.
This paper deals with an advanced design for a pump powered by solar energyto supply agricultural lands with water and also the maximum power point is used to extract the maximum value of the energy available inside the solar panels and comparing between techniques MPPT such as Incremental conductance, perturb & observe, fractional short current circuit, and fractional open voltage circuit to find the best technique among these. The solar system is designed with main parts: photovoltaic (PV) panel, direct current/direct current (DC/DC) converter, inverter, filter, and in addition, the battery is used to save energy in the event that there is an increased demand for energy and not to provide solar radiation, as well as saving energy in the case of generation more than demand. This work was done using the matrix laboratory (MATLAB) simulink program.
Electricity is a major source of energy for fast growing population and the use of nonrenewable source is harmful for our environment. This reason belongs to devastating of environment, so it is required to take immediate action to solve these problems which result the solar energy development. Production of a solar energy can be maximizing if we use solar follower. The major part of solar panels is microcontroller with arrangement of LDR sensor is used to follow the sun, where the sensors is less efficient to track the sun because of the low sensitivity of LDR. We are proposing a method to track sun more effetely with the help of both LDR sensors and image processing. This type of mechanism can track sun with the help of image processing software which combines both result of sensors and processed sun image to control the solar panel. The combination of both software and hardware can control thousands of solar panels in solar power plants.
A hybrid DC/DC/AC converter connected to the grid without a three-phase transformer is controlled. The decentralized control method is applied to the hybrid DC-DC converter such that the maximum power of PV flows to the grid side. This controller must charge and discharge the battery at the proper time. It must also regulate DC-link voltage. An additional advantage of the proposed control is that the three-phase inverter does not need a separate controller such as PWM and SPWM. A simple technique is used for creating the desired phase shift in the three-phase inverter, which makes the active and reactive power of the inverter controllable. A new configuration is also proposed to transmit and manage the generation power of PV. In this scheme, the battery and fuel cell are employed as an auxiliary source to manage the generation power of PV. Finally, a real-time simulation is performed to verify the effectiveness of the proposed controller and system by considering the real characteristics of PV and FC.
Direct current (DC) electronic load is a useful equipment for testing the electrical system. It can emulate various load at a high rating. The electronic load requires a power converter to operate and a linear regulator is a common option. Nonetheless, it is hard to control due to the temperature variation. This paper proposed a DC electronic load using the boost converter. The proposed electronic load operates in the continuous current mode and control using the integral controller. The electronic load using the boost converter is compared with the electronic load using the linear regulator. The results show that the boost converter able to operate as an electronic load with an error lower than 0.5% and response time lower than 13 ms.
New Structure for Photovoltaic SystemApplications with Maximum Power Point Tr...IAES-IJPEDS
This paper recommendes a new structure for photovoltaicsystems with a new inverter topology. A quasi-Z-source DC-DC converter with capability of dividing its output voltage to the same voltages and tracking maximum power point is proposed. The proportional-integral incremental conductance method is used for maximum power point tracking. The new recommended inverter topology is linked to quasi-Z-source converter for transferring power. For triggering inverter switches, alternate phase opposition disposition switching technique is utilized. A comparison is drawn between suggested multilevel inverter topology and other conventional multilevel inverter topologies. Description of proposed structure along with detailed simulation results that verify its feasibility are given to demonstrate the availability of the proposed system by MATLAB/Simulink software.
Development and Analysis of Fuzzy Control for MPPT Based Photovoltaic SystemIJERD Editor
In PV system control of Power electronics converters are very essential for the efficient utilization
of the solar System. This paper proposes modified Perturb & Observe Maximum power point tracking (MPPT)
with a fuzzy controller for DC-DC boost converter control in Photovoltaic system under shading and varying
atmospheric conditions. This paper proposes a different approach for MPPT of PV system so as to obtain
maximum power from PV system. In conventional methods, tracking power contains oscillation in the output
power. The Simulation and modeling of Photovoltaic system along with proposed algorithm are done using
MATLAB/SIMLINK software. Form Simulation results shows that P & O based fuzzy controller algorithm is
transient state is fast, less fluctuations and smooth in signal of generated power.
The impact of channel fin width on electrical characteristics of Si-FinFET IJECEIAES
This paper studies the impact of fin width of channel on temperature and electrical characteristics of fin field-effect transistor (FinFET). The simulation tool multi-gate field effect transistor (MuGFET) has been used to examine the FinFET characteristics. Transfer characteristics with various temperatures and channel fin width (W F =5, 10, 20, 40, and 80 nm) are at first simulated in this study. The results show that the increasing of environmental temperature tends to increase threshold voltage, while the subthreshold swing (SS) and drain-induced barrier lowering (DIBL) rise with rising working temperature. Also, the threshold voltage decreases with increasing channel fin width of transistor, while the SS and DIBL increase with increasing channel fin width of transistor, at minimum channel fin width, the SS is very near to the best and ideal then its value grows and going far from the ideal value with increasing channel fin width. So, according to these conditions, the minimum value as possible of fin width is the preferable one for FinFET with better electrical characteristics.
An optimum location of on-grid bifacial based photovoltaic system in Iraq IJECEIAES
Bifacial photovoltaic (PV) module can gain 30% more energy compared to monofacial if a suitable location were chosen. Iraq (a Middle East country) has a variable irradiation level according to its geographic coordinates, thus, the performance of PV systems differs. This paper an array (17 series, 13 parallel) was chosen to produce 100 kWp for an on-grid PV system. It investigates the PV system in three cities in Iraq (Mosul, Baghdad, and Basrah). Effect of albedo factor, high and pitch of the bifacial module on energy yield have been studied using PVsyst (software). It has been found that the effect is less for a pitch greater than 6 m. The energy gained from bifacial and monofacial PV system module in these cities shows that Mosul is the most suitable for installing both PV systems followed by Baghdad and lastly Basrah. However, in Basrah, the bifacial gain is 12% higher in the energy than monofacial as irradiation there is higher than the other locations, especially for elevation above 1.5 m. Moreover, the cost of bifacial array is 7.23% higher than monofacial, but this additional cost is acceptable since the bifacial gain is about 11.3% higher energy compared to the monofacial.
Improving efficiency of Photovoltaic System with Neural Network Based MPPT Co...IJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
On The Origin of Electromagnetic Waves from Lightning DischargesIOSR Journals
Interaction of up going ion beam forming current flow in the pre-ionized stepped leader plasma and
the way, how the kinetic energy of the beam particles is converted into electromagnetic energy have been
discussed. The ion beam interaction with the plasma wave modes in the stepped leader channel produces
perturbations in the return stroke current flow and changes its uniformity and becomes non-uniform. In the
present study, the return current is taken to be deeply modulated at a given modulation frequency, and
considered that it behaves like an antenna for electromagnetic radiation. In this paper the total amount of
energy associated with return stroke is given to electromagnetic waves is estimated.
Periodic Table Gets Crowded In Year 2011.IOSR Journals
Abstract: Year 2011, has been specially important for teachers and students of chemistry, as after a gap of about 14 years at least five new elements were named and included in the periodic table. All these elements are synthetic and radioactive and some were actually made in 1999, but got their name and status by IUPAC, in July 2011. The total number of elements now in periodic table is 112, and scientists are trying their best to prepare elements with atomic numbers 118, 119 and 120 as well.
IOSR Journal of Mathematics(IOSR-JM) is an open access international journal that provides rapid publication (within a month) of articles in all areas of mathemetics and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in mathematics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
In theoretical computer science and mathematics , the theory of computation is the branch that
deals with how efficiently problems can be solved on a model of computation, using an algorithm. The field is
divided into three major branches: automata theory, computability theory, and computational complexity
theory.
In order to perform a rigorous study of computation, computer scientists work with a mathematical
abstraction of computers called a model of computation. There are several models in use such as Lambda
calculus, Combinatory logic, mu-recursive functions , but the most commonly examined is the Turing machine.
Computer scientists study the Turing machine because it is simple to formulate, can be analyzed and used to
prove results, and because it represents what many consider the most powerful possible "reasonable" model of
computation . It might seem that the potentially infinite memory capacity is an unrealizable attribute, but
any decidable problem solved by a Turing machine will always require only a finite amount of memory. So in
principle, any problem that can be solved (decided) by a Turing machine can be solved by a computer that has a
bounded amount of memory.
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phenomenon
switches.
Stiction
failures
in
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H1102034954
1. IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE)
e-ISSN: 2278-1676,p-ISSN: 2320-3331, Volume 11, Issue 2 Ver. III (Mar. – Apr. 2016), PP 49-54
www.iosrjournals.org
DOI: 10.9790/1676-1102034954 www.iosrjournals.org 49 | Page
Design And Analysis of Various SU 8 Structures for On/Off
Mems Switch in RF Applications
Venkateswarlu S1
, Bidhan Pramanick2
, Chinmoy Saha1
1
(Avionics, IIST, Trivandrum, India)
2
(UC Irvine, CA, USA and Tec de Monterrey, Mexico)
Abstract : This paper presents new design techniques of SU-8 RF MEMS switches for low voltage
applications. Three different configurations, namely cantilever based, clamped-clamped and meandered, has
been proposed to SU-8 2005 (5 µm) beam structure driven by electrostatic force. Proposed structure has been
designed and simulated using Coventorware software. Pull-in voltage for clamped-clamped beam configuration
varies within 4 – 7 V for various widths, where as for other two configurations pull-in voltage is 2.5 V. The pull-
in voltage analysis has also been carried out for different beam materials to choose the optimum one for
fabrication. It is revealed that beam with SU-8 materials presents the lower pull-in and is most suitable for
practical use. The proposed switch is simulated for RF analysis using Agillent ADS and HFSS and Simulation
results shown that the switch exhibits insertion loss of 0.37 dB at 6 GHz and 1 dB up to 10 GHz and isolation of
20 dB at 6 GHz and 15 dB up to 10 GHz. Proposed switches are highly compact, low profile with less operating
voltage and can be easily integrated into planar passive microwave components for reconfigurable applications
requiring compatible switches.
Keywords : RF MEMS, Switches, SU-8, pull-in voltage, fabrication
I. Introduction
The research in the field Micro-electro Mechanical systems (MEMS) has grown up exponentially during
the last two decades due to their diversified applications in various branches of engineering. In the MEMS field
devices are conventionally fabricated using Si-based materials. However, polymer, especially SU-8 has recently
become one of the promising materials [1] due to various practical advantages. SU-8 has several interesting and
useful material characteristics, including photosensitivity, transparency to visible light, low Young‟s modulus,
chemical resistance and biocompatibility. The fact is that SU-8 has about 30 times smaller Young‟s modulus than
Silicon ( ESU-8 = 2 – 4 GPa [2] and Esi = 164 GPa [3]).
The SU-8 polymer, epoxy based negative photoresist material invented by IBM, which is widely used in
RF MEMS switching devices as structural and sacrificial material.SU-8 has various groups based on the
polymerization process like SU-8 2000 and SU-8 3000. SU-8 2000 series are available in twelve standard
viscosities [4]. Design of SU-8 based switches has emerged as one of the most enthralling work to the MEMS
community over last few years. Andrea Lucibello et.al has designed a double clamped RF MEMS capacitive
switch in the coplanar configuration with SU-8 as sacrificial material for lateral supports [5]. A clamped-clamped
beam switch was developed by Chao et.al with SU-8/Cu/SU-8 sandwich layer as a structural material [6]. The
process might be good for RF switch. However, the stacked layer with comparable thickness of Cu with SU-8
increases the spring constant of structural beam and results in higher pull-in voltage. After that K.S. Ramadan
et.al developed a switch with two metal electrodes using amorphous silicon as a sacrificial material [7].
2. Design And Analysis Of Various SU 8 Structures For ON/OFF MEMS Switch In RF Applications
DOI: 10.9790/1676-1102034954 www.iosrjournals.org 50 | Page
This paper presents three different implementations of RF MEMS switches on SU-8 material. Physical
dimension and configuration of the switches ensures their compatibility in using in planar transmission line to
achieve electrical short/open condition. Such reconfigurable transmission line can drastically change the
operation of various microwave components, waveguides [8], antennas [9-17] and circuits [18-24] providing a
switchable control over the performance of the RF circuits and radiators [25]-[26]. However, performance of such
reconfigurable RF circuits and/or antennas is predominantly dependent on the characteristics of the switch
embedded in the module. MEMS switch in RF applications is an appealing choice thanks to its low insertion loss,
virtually no energy consumption, excellent quality factor (Q), RF isolation and less expensive as compared to
conventional solid state switches. The design of RF MEMS switches can be varied according to their
uses, either series or shunt configuration and can move vertically or laterally. The MEMS switches can provide
both capacitive and metal-to-metal connection. Their movement can be carried out via electrostatic,
magnetostatic, piezoelectric or thermal actuation. Various types of MEMS switches include cantilever, clamped-
clamped, meander and other structures electronically arranged in series or parallel with the RF transmission line.
Cantilever beams are useful in many situations where it is inconvenient to fix both ends of the beam. Since it is
not fixed at one end, any residual stress within the film is released and the spring constant does not contain any
residual component which results low pull-in voltage. However, if there is a stress gradient over the cross section
of the cantilever, then the beam deflects up/down side on release and it is undesirable [28]. On the other hand
clamped-clamped beam doesn‟t have any deflection problem but exhibits higher pull-in voltage.
In this paper, three different configurations of RF MEMS switches, cantilever type, clamped-clamped beam type
and a meander type is designed and simulated using proposed SU-8 micromachining technique for
reconfigurable applications in RF circuits/antennas. The switch geometry and dimensions are properly
optimized to achieve targeted pull-in voltage,Vp<= 5V and proper operational frequency.
II. Desig
In general, to design a RF MEMS electrostatic actuated switch, the structure of the switch beam must be
chosen so as to produce the lowest possible insertion loss, the highest possible isolation, the highest possible
switching frequency, and lowest possible actuation voltage. The SU-8 polymer has Young‟s modulus of 2 to 4
GPa, much lower than poly-The RF switch is fabricated on a silicon wafer with 1 µm thermally grown silicon
dioxide considered as a substrate. The beam is assumed to be SU-8 2005 material of thickness 5 µm. The
electrodes are of Cu material of thickness 0.5 µm on both top and bottom of the beam using POLYIMIDE as
sacrificial material and patterned to realize cantilever, clamped-clamped and meander structures. Fig.1 shows 3D
view of three types of structures.
3. Design And Analysis Of Various SU 8 Structures For ON/OFF MEMS Switch In RF Applications
DOI: 10.9790/1676-1102034954 www.iosrjournals.org 51 | Page
The mechanical design of electrostatically actuated switches is dictated by the required actuation voltage. When
designing a switch with low actuation voltage, the choice of membrane material and the support beam design
are critical. Equation (1) is the governing equation for calculating pull-in voltage of electrostatically actuated
MEMS switches [19] given by equation 1.
𝑉𝑝 =
8𝑘 𝑔0 +
𝑡 𝑑
𝜀 𝑟
3
27𝜀𝐴
(1)
Where g0 is the initial gap between electrodes, ε is the permittivity of the medium between electrodes,
td is thickness of SU-8 membrane, εr is the dielectric constant of SU-8 and A is the area of the electrodes. The
spring constant k, depends on the type and dimensions of membrane. The design formulae for k were discussed
in [18, 19]. The necessary parameters for cantilever, clamped-clamped and meander structures are shown in
Fig.1.
III. Simulation results
The designed switches have been actuated with a voltage ramp, 0 to 10 V to upper electrodes and lower
electrodes were grounded. Three different switch configurations conceived in this paper is simulated in
Coventorware, providing a pull-in voltage of 2.5 V, 5 V and 2.5 V for cantilever, clamped-clamped and
meander beam switch configurations respectively. Fig.2 shows the vertical („z‟ direction) displacement for
various switch configurations at pull-in voltage. It can be observed that the maximum deflection takes place at
the free end of beam for cantilever configuration, and centre of the beam for both clamped-clamped and
meander configuration as expected. The displacement as a function of applied voltage for all three beams is
shown in Fig. 3. It can be shown that the negative z-displacement of the beam for various voltages ensuring the
anticipated downward movement.
4. Design And Analysis Of Various SU 8 Structures For ON/OFF MEMS Switch In RF Applications
DOI: 10.9790/1676-1102034954 www.iosrjournals.org 52 | Page
A. Material Selection
We have used some standard materials of same dimensions to compare the pull-in voltage with SU-8
structure for MEMS switch. As shown in Table 1, different materials were used for clamped-clamped beam
MEMS switch at beam width 200 µm and pull-in voltage was obtained. Simulation results showed that SU-8
material gives lowest pull-in voltage compared with other materials. So SU-8 was selected for lower actuation
voltage applications
B. Relationship Between Pull-In Voltage And Width Of The Beam
Table 2 illustrates the relationship between pull-in voltage and width of the beam with thickness 5 µm.
When width of the beam is decreased from 500 µm to 150 µm, the pull-in voltage is reduced from 7V to 4.5V.
C. Relationship between Resonant frequency and the width of the beam
Table 3 shows the resonant (modal) frequency at various beam widths for the first three modes of the
clamped-clamped beam switch. When width is increased from 150 µm to 500 µm, the resonant frequency is
increased for all modes.
The designed switch is simulated for insertion loss and Isolation in Agilent ADS software with the
lumped equivalent model shown in Fig. 4(a) & 4(b). Simulation results from shown that the switch exhibits
insertion loss of 0.37 dB at 6 GHz and 1 dB up to 10 GHz in Fig. 5(a) and Isolation of 20 dB at 6 GHz and 15
dB up to 10 GHz in Fig. 5(b). There is a variation in lumped modal results from HFSS simulation results due to
fringing effect. Fig. 6(a) & 6(b) shows the simulated current distribution of CPW transmission line when the
5. Design And Analysis Of Various SU 8 Structures For ON/OFF MEMS Switch In RF Applications
DOI: 10.9790/1676-1102034954 www.iosrjournals.org 53 | Page
switch in the upstate and downstate condition from high-frequency structure simulator (HFSS) software from
Ansoft. As shown in Fig. 6(a), when the switch is in the upstate, the total amount current is flowing from input
port to the output port and very low current is passing to the ground. From Fig. 6(b), when the switch is in the
down-state, the front edges of the contact pad that are over the CPW slot act as short paths from the centre
conductor to the ground. Therefore, the current in the metal bridge is mainly concentrated on the front edges of
the metal bridge that are over the CPW slot. This implies that for the DC contact MEMS switch, the down-state
inductance is also mainly determined by the portion of the metal bridge over the CPW slots. Therefore, when
the dimensions of the CPW slot are reduced, the inductance of the switch can also be reduced.
IV. Conclusion
RF industry demands for low voltage operated switch. Polymer based switches have the potential to
fulfill the requirements. The switch structures discussed in this paper have all of the characteristics which make
them ideal for RF application. In addition, those switches ideally consume no power. This work is mainly
motivated by low operation voltage demand. Choice of membrane material is also an important object for this
work. SU-8 is chosen among the materials like Cu, Al, Cr, and Poly-Si. Three designs, cantilever, clamped-
clamped and meander structure are considered for the analyses of low voltage operation and meander structure
shows lowest among them for the same dimensions.
References
[1]. Lorenz, H., Despont, M., Fahrni, N., Labiancia, N., Renaud, P., And Vettiger, P. (1997). Su-8: A Low Cost Negative Resist For
Mems. Journal Of Micromechanics And Microengineering, 1997. 7: P. 121-124
[2]. M. Hopcroft, T. Kramer, G. Kim, K. Takashima, Y. Higo, D. Moore, And J. Brugger, “Micromechanical Testing Of Su-8
Cantilivers,” Fatigue Fracture Eng. Master. Struct., Vol. 28, No. 8, Pp. 735-742, 2004.
[3]. Steven Kehrberg, Markus Dorwarth, Sebastian Gtinther, Steffen Markisch, Carsten Geckeler And Jan Mehnert, “Measuring
Young's Modulus Of Polysilicon Via Cantilever Microbeam Arrays”, In 2014 15th International Conference On Thermal,
Mechanical And Multi-Physics Simulation And Experiments In Microelectronics And Microsystems, Eurosime 2014
[4]. Http://Www.Microchem.Com/Prod-Su8 2000.Htm.
[5]. Romolo Marcelli , Simone Catoni, Luciano Frenguelli, “Low-Loss Microwave Interconnections By Using Polymeric Based
Coplanar Waveguides On Low Resistivity Silicon Substrates”, In Microelectronic Engineering 85 (2008) 425–431.
[6]. Andrea Lucibello, Emanuela Proietti, Flavio Giacomozzi, Romolo Marcelli, Giancarlo Bartolucci, Giorgio De Angelis, “ Rf Mems
Switches Fabrication By Using Su-8 Technology” Design, Test, Integration And Packaging Of Mems/Meoms(Dtip) 2012
Symposium.
[7]. Tzu-Yuan Chao, M C Hsu, C-D Lin And Y T Cheng, “ Su-8 Serial Mems Switch For Flexible Rf Applications” Journal Of
Micromechanics And Microengineering.
[8]. Khaled S Ramadan, Tarek Nasr And Ian G Foulds, “Development Of An Su-8 Mems Process With Two Metal Electrodes Using
Amorphous Silicon As A Sacrificial Material”, Journal Of Micromechanics And Microengineering, 2013
[9]. Y Li1, S Kuhne, D Psychogiou, J Hesselbarth And C Hierold, “A Microdevice With Large Deflection For Variable-Ratio Rf Mems
Power Divider Applications”, Journal Of Micromechanics And Microengineering, 2011
[10]. Anil Kumar Sahui And B K Sarkar, “A Novel Low Actuation Voltage Rf Mems Shunt Capacitive Switch”, Ieee, 2009.
[11]. Tejinder Singh, Student Member, Ieee, Navjot Khaira, Student Member, Ieee, Jitendra Sengar, Member, Ieee, “A Novel Capacitive
Rf Mems Switch Design For Low Voltage Applications” Ieee, 4th Icccnt 2013.
[12]. Anna Persano, Adriano Cola, Giorgio De Angelis, Antonietta Taurino, Pietro Siciliano, And Fabio Quaranta, “Capacitive Rf Mems
Switches With Tantalum-Based Materials”, Journal Of Microelectromechanical Systems, Vol. 20, No. 2, April 2011.
[13]. Yong-Ha Song, Min-Wu Kim, Min-Ho Seo, And Jun-Bo Yoon, Member, Ieee, “A Complementary Dual-Contact Mems Switch
Using A “Zipping” Technique, Journal Of Microelectromechanical Systems, Vol. 23, No. 3, June 2014.
[14]. Sara S. Attar, Student Member, Ieee, Sormeh Setoodeh, Associate Member, Ieee, Raafat R. Mansour, Fellow, Ieee, And
Deepnarayan Gupta, Senior Member, Ieee, “Low-Temperature Superconducting Dc-Contact Rf Mems Switch For Cryogenic
Reconfigurable Rf Front-Ends”, Ieee Transactions On Microwave Theory And Techniques, Vol. 62, No. 7, July 2014.
[15]. E.S.Shajahan, Shankaranarayana, M Bhat, “Tuned Dual Beam Low Voltage Rf Mems Capacitive Switches For X – Band
Applications”, Ieee-Icse2012 Proc., 2012, Kuala Lumpur, Malaysia.
[16]. Hamid Moghadas, Mojgan Daneshmand, And Pedram Mousavi, “Mems-Tunable Half Phase Gradient Partially Reflective Surface
For Beam-Shaping”, Ieee Transactions On Antennas And Propagation, Vol. 63, No. 1, January 2015.
[17]. Harish Rajagopalan, Member, Ieee, Joshua M. Kovitz, Student Member, Ieee, And Yahya Rahmat-Samii, Fellow, Ieee, “Mems
Reconfigurable Optimized E-Shaped Patch Antenna Design For Cognitive Radio”, Ieee Transactions On Antennas And
Propagation, Vol. 62, No. 3, March 2014.
[18]. Debajit De And Neela Chattoraj, “Rf Mems Tcas Patch Antenna”, International Conference On Communication And Signal
Processing, April 3-5, 2014, India.
[19]. Ozan Dogan Gurbuz, Student Member, Ieee, And Gabriel M. Rebeiz, Fellow, Ieee, “A 1.6–2.3-Ghz Rf Mems Reconfigurable
Quadrature Coupler And Its Application To A 360 Reflective-Type Phase Shifter”, Ieee Transactions On Microwave Theory And
Techniques, Vol. 63, No. 2, February 2015.
[20]. King Yuk Chan, Member, Ieee, Rodica Ramer, Senior Member, Ieee, Raafat R. Mansour, Fellow, Ieee, And Yingjie Jay Guo,
Fellow, Ieee, “60 Ghz To E-Band Switchable Bandpass Filter”, Ieee Microwave And Wireless Components Letters, Vol. 24, No. 8,
August 2014.
[21]. Tianyu Jia1, Jing Yeo And Zewen Liu1, “A Rf-Mems Based Dual-Band Tunable Filter With Independently Controllable
Passbands”, Ieee, 2014.
[22]. Buddhadev Pradhan, Bhaskar Gupta, “Rf Mems Tunable Band Reject Filter Using Metamaterials” Ieee Conference Publications,
2014.
[23]. Maher Bakri-Kassem, Raafat R. Mansour, Safieddin Safavi-Naeini, “A Novel Latching Rf Mems Phase Shifter”, 9th European
Microwave Integrated Circuits Conference, 2014.
6. Design And Analysis Of Various SU 8 Structures For ON/OFF MEMS Switch In RF Applications
DOI: 10.9790/1676-1102034954 www.iosrjournals.org 54 | Page
[24]. R. Malmqvist, P. Rantakari, C. Samuelsson, M. Lahti, S. Cheng, J. Saijets, T. Vähä-Heikkilä, A. Rydberg, J. Varis, “Rf Mems
Based Impedance Matching Networks For Tunable Multi-Band Microwave Low Noise Amplifiers”, Ieee,2009.
[25]. Robert Malmqvist, Carl Samuelsson, Shakila Reyaz, Andreas Gustafsson, Seonho Seok, Michel Fryziel, Paul-Alain Rolland, Brice
Grandchamp And Rens Baggen, “A Gaas Mmic Single-Chip Rf-Mems Switched Tunable Lna”, Ieee, 2013.
[26]. J.Y. Siddiqui, C. Saha And Y.M.M. Antar, “A Novel Ultra Wideband (Uwb) Printed Antenna With A Dual Complemetary
Characteristics”, Ieee Antennas And Wireless Propag. Lett. , (Accepted For Publication).
[27]. C. Saha, J.Y. Siddiqui And Yahia M.M. Antar “Compact Srr Loaded Uwb Circular Monopole Antenna With Reconfigurable
Characteristics” In Proc. Ieee Aps Orlando, Florida, Usa July 2013.
[28]. Kuang-Shun Ou And Kuo-Shen Chen, “Pull-In Voltage Estimation Of Microcantilever Beams With Effects Of Residual Stress
Gradients And Capacitance Fringing”, Ieee Transactions On Device And Materials Reliability, Vol. 14, No. 1, March 2014.