1) The document presents a simulation of a SPWM based Z-source inverter. Z-source inverters can boost or buck the output voltage from a DC supply, overcoming limitations of traditional voltage source inverters.
2) MATLAB/Simulink models were developed for a Z-source inverter feeding resistive, inductive, and motor loads. Simulation results validated that the Z-source inverter has lower total harmonic distortion than traditional voltage source and current source inverters.
3) The Z-source inverter topology was analyzed and its operating principle explained. Sinusoidal pulse width modulation was used for switching control. Simulation results showed improved performance of the Z-source inverter over
Simulation of Z-Source Inverter Fed Three Phase Induction Motor DriveIJSRD
This paper presents performance characteristics of Z-source inverter (ZSI) fed Induction Motor (IM) drives. Z-Source inverter is a single stage converter which performs both buck-boost energy conversions using the LC impedance network. This reduces the voltage range of the capacitors used and also the cost of the proposed topology which is in turn used to control the speed of an induction motor which is used in many valuable industrial applications. The Z Source inverter is a combined inverter with an additional buck-boost feature and the proposed topology increases the efficiency of the circuit by reducing the voltage stress across the capacitors. The z-source inverter is very advantageous over traditional inverters and we can be employed all ac and dc power conversion applications. Z-source inverter can boost dc input voltage with no requirement of dc to dc boost converter or step up transformer hence overcoming output voltage limitation of voltage source inverter as well as lower cost. A comparison among conventional PWM inverter dc to dc boost PWM inverter and control circuit cost which are the main a power electronics system.
Improved Trans-Z-source Inverter for Automobile ApplicationIJTET Journal
In this paper a new technology is proposed with a replacement of conventional voltage source/current
source inverter with Improved Trans-Z-source inverter in automobile applications. The improved Trans-Z-source
inverter has a high boost inversion capability and continues input current. Also this new inverter can suppress the
resonant current at the startup; this resonant current in the startup may lead the device to permanent damage. In
improved Trans-Z-source inverter a couple inductor is needed, instead of this coupled inductor a transformer is used.
By using a transformer with sufficient turns ratio the size can be reduced. The turn’s ratio of the transformer decides
the input voltage of the inverter. In this paper operating principle, comparison with conventional inverters, working
with automobiles simulation results, THD analysis, Hardware implementation using ATMEGA 328 P are included.
Design and Control of Switched-Inductor Quasi-Z-Source Inverter for Photovolt...irjes
The conventional Z-Source Inverter (ZSI) used for photovoltaic applications has certain
shortcomings such as high stress across the passive components and low boost factor. This paper presents the
design and analysis of three phase switched inductor quasi Z-source inverter (SL-QZSI) for photovoltaic (PV)
applications. The wide voltage gain and the compensation for dead time effect of SL-QZSI with the help of
shoot-through states makes it suitable for PV application. Modulation strategies such as Simple boost,
Maximum boost and Constant maximum boost control methods are investigated for the operation and control
of SL-QZSI. PV source is modeled in MATLAB and incremental & conductance MPPT algorithm is
implemented .Simulation of the SL-QZSI circuit powered by PV source is carried out by implementing
maximum boost control method and the performance parameters are discussed.
SIMULATION AND ASSESSMENT OF SINGLE PHASE SEMI-Z-SOURCE INVERTER (S-ZSI)IAEME Publication
The present investigation is a step towards the development of a single phase semi-Z-source inverter (s-ZSI) with photovoltaic, its topology and the assessment with respect to the voltage and current output. The proposed semi-Z-source inverter use only two active switches to achieve a desired output. The simulation was carried out using MATLAB and the results are discussed in various waveforms.
Simulation of Z-Source Inverter Fed Three Phase Induction Motor DriveIJSRD
This paper presents performance characteristics of Z-source inverter (ZSI) fed Induction Motor (IM) drives. Z-Source inverter is a single stage converter which performs both buck-boost energy conversions using the LC impedance network. This reduces the voltage range of the capacitors used and also the cost of the proposed topology which is in turn used to control the speed of an induction motor which is used in many valuable industrial applications. The Z Source inverter is a combined inverter with an additional buck-boost feature and the proposed topology increases the efficiency of the circuit by reducing the voltage stress across the capacitors. The z-source inverter is very advantageous over traditional inverters and we can be employed all ac and dc power conversion applications. Z-source inverter can boost dc input voltage with no requirement of dc to dc boost converter or step up transformer hence overcoming output voltage limitation of voltage source inverter as well as lower cost. A comparison among conventional PWM inverter dc to dc boost PWM inverter and control circuit cost which are the main a power electronics system.
Improved Trans-Z-source Inverter for Automobile ApplicationIJTET Journal
In this paper a new technology is proposed with a replacement of conventional voltage source/current
source inverter with Improved Trans-Z-source inverter in automobile applications. The improved Trans-Z-source
inverter has a high boost inversion capability and continues input current. Also this new inverter can suppress the
resonant current at the startup; this resonant current in the startup may lead the device to permanent damage. In
improved Trans-Z-source inverter a couple inductor is needed, instead of this coupled inductor a transformer is used.
By using a transformer with sufficient turns ratio the size can be reduced. The turn’s ratio of the transformer decides
the input voltage of the inverter. In this paper operating principle, comparison with conventional inverters, working
with automobiles simulation results, THD analysis, Hardware implementation using ATMEGA 328 P are included.
Design and Control of Switched-Inductor Quasi-Z-Source Inverter for Photovolt...irjes
The conventional Z-Source Inverter (ZSI) used for photovoltaic applications has certain
shortcomings such as high stress across the passive components and low boost factor. This paper presents the
design and analysis of three phase switched inductor quasi Z-source inverter (SL-QZSI) for photovoltaic (PV)
applications. The wide voltage gain and the compensation for dead time effect of SL-QZSI with the help of
shoot-through states makes it suitable for PV application. Modulation strategies such as Simple boost,
Maximum boost and Constant maximum boost control methods are investigated for the operation and control
of SL-QZSI. PV source is modeled in MATLAB and incremental & conductance MPPT algorithm is
implemented .Simulation of the SL-QZSI circuit powered by PV source is carried out by implementing
maximum boost control method and the performance parameters are discussed.
SIMULATION AND ASSESSMENT OF SINGLE PHASE SEMI-Z-SOURCE INVERTER (S-ZSI)IAEME Publication
The present investigation is a step towards the development of a single phase semi-Z-source inverter (s-ZSI) with photovoltaic, its topology and the assessment with respect to the voltage and current output. The proposed semi-Z-source inverter use only two active switches to achieve a desired output. The simulation was carried out using MATLAB and the results are discussed in various waveforms.
Application of PWM Control Strategy on Z-Source Isolated Dual active bridge D...IJMER
This project presents a Z-source with bidirectional dc–dc converter. The switching count is
reduced by adding a passive element. Thus, we are improving the output voltage level. The voltage
regulation range of proposed converter is better than that of the traditional bidirectional dc–dc
converter. The fully bridge symmetrical circuit configuration, is neither a high-voltage side nor a lowvoltage
side in the circuit structure, and the sources connected to the dc side of each H-bridge circuit
with voltage sources and current sources. This method can reduce current stress and improves the
system efficiency.
In this paper we are presenting a dual active bridge (DAB) dc–dc converter is also known as
Bidirectional DC-DC converter. Both simulation results are shown by using MATLAB software.
Analysis and hardware implementation of five level cascaded H Bridge inverterIJERA Editor
The cascaded multilevel inverter (CMLI) has gained much attention in recent years due to its advantages in high
voltage and high power with low harmonics applications. A standard cascaded multilevel inverter requires n DC
sources for 2n+1levels at the output, where n is the number of inverter stages. This paper presents a topology to
control cascaded multilevel inverter that is implemented with multiple DC sources to get 2"+1_ 1 levels. Without
using Pulse Width Modulation (PWM) technique, the firing circuit can be implemented using Microcontroller
which greatly reduces the Total Harmonic Distortion (THD) and switching losses. To develop the model of a
cascaded hybrid multilevel inverter, a simulation is done based on MATLAB/SIMULINK software and
hardware implementation was also done. Their integration makes the design and analysis of a hybrid multilevel
inverter more complete and detailed.
A Single Phase Eleven Level Cascaded H-Bridge Multilevel Inverter for Photovo...IJMER
Abstract: A Cascaded H-Bridge Multilevel Inverter is a power electronic converter built to synthesize a desired ac voltage
from several levels of dc voltages with better harmonic spectrum. Such inverters are suitable for high voltage and high
power applications and have been an important development in recent years. This paper presents the performance of a
eleven level cascaded H-Bridge multilevel inverter topology with multicarrier pulse width modulation technique for
photovoltaic cell. This inverter is capable of producing eleven levels of output voltage from the dc supply voltage. This
topology magnifies the fundamental output voltage with reduction in total harmonic distortion . The output is drawn near the
sine wave because of more levels. It can also be easily extended to an m-level inverter. The performance of the proposed
PWM strategy in terms of output voltage and THD is shown using MATLAB/Simulink.
Keywords: Multilevel inverter, Cascaded H-Bridge multilevel inverter, Multicarrier pulse width modulation, PV cell, Total
harmonic distortion.
Comparative analysis of multilevel inverter topologies for induction motor dr...eSAT Journals
Abstract Induction motors are widely used in industries, because they are rugged, reliable and economical and hence they are called as work horse power of industry. Induction motor drive requires suitable converters to get the required speed and torque without or negligible ripples. Multilevel inverters can do this job. But the conventional MLIs such as Diode Clamped MLIs requires extra diodes in conjunction with the active switches, Flying capacitor MLIs requires extra Capacitors and control also difficult if the levels increases and the Cascaded H-bridge MLIs requires separate dc sources which limits its use. This paper proposes a new type of multi level Inverter which converts the dc into ac using less number of switches when compared to conventional multilevel Inverters. The proposed Inverter uses only seven switches to get 13-level output voltage compared conventional cascaded H-bridge uses twelve switches. The comparison between the conventional MLIs and proposed inverter is presented in this paper. Finally the induction motor using proposed inverter with thirteen level is simulated using Matlab/Simulink environment and the corresponding results are presented in this paper. Keywords- Grid interconnection, PV system, MLI, Renewable energy sources (RES).
Analysis of Impedance Source Inverter Topologies for Grid Integration of PV I...IJPEDS-IAES
In this paper, the performance of different Impedance Source Inverter (ZSI)
topologies in implementing single stage power conversion for grid
ingetertion of PV power converters is discussed. Unlike the traditional
inverters, ZSI employs a distinctive impedance network, there by making
shoot-through state is possible. The independent control variables are shootthrough
duty ratio and modulation index. Simple Boost Control pulse width
modulation technique was used in this work to vary the modulation index.
Here the basic operation, simple boost control method, characteristics,
requirements and harmonic analysis of the classical Z-Source Inverter (ZSI),
TZ-Source Inverter (TZSI), Trans-Z-Source Inverter (Trans-ZSI) and
Improved ZSI (IMZSI) topologies were compared for interfacing the wide
range variable input energy to utility supply system. The performances were
compared based on its MATLAB/SIMULINK simulation model and featured
results are shown to confirm its validity.
Implementation of Cascaded H-bridge MULTI-LEVEL INVERTEREditor IJMTER
The classical two level inverter produce output with levels either Vdc or -Vdc. The output
voltage waveform of ideal inverter should be sinusoidal but the waveform of conventional inverters
is non-sinusoidal and contains certain harmonics. Large capacitor is normally connected across the
DC voltage source and such a capacitor is costly and demands space. In order to overcome these
drawbacks Multi level inverters are introduced. The great advantage of this kind of inverter is the
minimum harmonic distortion obtained. Power electronics is the applications of power
semiconductor devices for the control and conversion of electric power such that these devices
operate as switches. An inverter is an electrical device that converts DC voltage to AC voltage; the
resulting AC can be at any required frequency. Multi-level inverters are nothing but the modification
of basic bridge inverters [1]. The multilevel inverter collectively converts the several levels of dc
voltage to a desired ac voltage. The unique structure of multilevel inverters allows them to reach
nearer to sinusoidal i.e., with low harmonics. In this project the work is done on five & nine level
multilevel inverter but the multilevel can be done up to any level and how many levels we increase
that much precise sinusoidal supply we can get i.e., we can reduce that many harmonics from the
supply. Simulation work is done using the MATLAB software
it is the most simplest presentation which is easy for preparetion and presentation.if u want some more information about multilevel inverter then follow the link given below
https://www.theengineeringprojects.com/2014/12/introduction-multilevel-inverters.html
Comparison of Sine and Space Vector Modulated Embedded Z-Source Inverter fed ...IAES-IJPEDS
This paper deals with performance of photovoltaic powered Embedded
Z-Source Inverter (EZSI) fed Induction motor drive. The DC output from the
PV-Panel is boosted and converted into AC using Embedded Z-Source
Inverter. EZSI system based on the concept of Z-Source Inverter (ZSI),
which provides single stage power conversion. The EZSI also produce same
voltage gain as that of the ZSI based system. In EZSI the DC source is
embedded within the X-shaped LC impedance network, due to this EZSI has
the added advantage of inherent source filtering capability, this can be
achieved without any extra passive filter. EZSI can produce the AC output
voltage which is greater than the DC link voltage. EZSI system also provides
ride-through capability under voltage sags. In this paper the performance of
space vector modulated EZSI fed Induction Motor Drive is compared with
sinusoidal PWM controlled EZSI fed Drive system. The PV powered EZSI
fed three phase Induction Motor System is designed, modeled and simulated
using MAT LAB-SIMULINK and the corresponding results are presented.
This drive system has advantages like voltage boosting ability and reduced
harmonic content.
Performance and Analysis of Hybrid Multilevel Inverter fed Induction Motor Drivernvsubbarao koppineni
This paper presents the Five level inverter with single DC source which is used to generate a five level output with two bridges and six switches and performance of three phase induction motor is analyzed when connected to PV array For this two identical dc sources of 50V each for two bridges in five levels using Multi level inverter and five level output is obtained by using a single DC source of 100V with six switches. A virtual DC source (charged capacitor acts as virtual DC source) is used for getting the output. The same technique is implemented for three-phase circuit i.e. by using single DC source. An asynchronous motor (three-phase) is connected as load and its performance characteristics are analyzed. And further the DC source is replaced by a renewable resource such as solar panels, fuel cell etc. and DC voltage is obtained. Performance characteristics of three-phase asynchronous motor are analyzed with PV array connected. The method can be easily extended to an m-level inverter.
An Improved the High Voltage Boost Inversion Ability of Switched Inductor Qua...IJSRD
This paper presents an improved the high voltage boost inversion ability of switched inductor quasi ZSI by using Boost PWM technique. This presents a comparative analysis of Boost Inversion Ability of Switched Inductor Quasi z-source inverter (SL-QZSI) with conventional z-source Inverter (ZSI). In comparison to conventional ZSI for the same value of voltages in the input and output the proposed SL-QZSI provides the less count on passive component a dc-source with common ground less voltage across the capacitors it gives the continuous input current current shoot through is reduced and also the current stress across the inductor and diodes are reduced. This thesis presents the operating principle boost inversion ability analysis simulation results and comparison of conventional ZSI with SLQZSI The simulation results confirmed the ability of high step up inversion by this proposed SL-QZSI. An extended switched inductor quasi z-source inverter (ESL-QZSI) with high boost voltage inversion ability is presented which combines the SL-QZSI with the traditional boost converter as well as improves the switched-inductor cell. Compared with the classic SL-QZSI topologies the proposed topology reduces the voltage stresses of capacitors power devices and diodes for the same input. The operation principle of the proposed topology is analyzed in detail. In addition, the performance of the proposed topology is verified by simulations and experiments.
Application of PWM Control Strategy on Z-Source Isolated Dual active bridge D...IJMER
This project presents a Z-source with bidirectional dc–dc converter. The switching count is
reduced by adding a passive element. Thus, we are improving the output voltage level. The voltage
regulation range of proposed converter is better than that of the traditional bidirectional dc–dc
converter. The fully bridge symmetrical circuit configuration, is neither a high-voltage side nor a lowvoltage
side in the circuit structure, and the sources connected to the dc side of each H-bridge circuit
with voltage sources and current sources. This method can reduce current stress and improves the
system efficiency.
In this paper we are presenting a dual active bridge (DAB) dc–dc converter is also known as
Bidirectional DC-DC converter. Both simulation results are shown by using MATLAB software.
Analysis and hardware implementation of five level cascaded H Bridge inverterIJERA Editor
The cascaded multilevel inverter (CMLI) has gained much attention in recent years due to its advantages in high
voltage and high power with low harmonics applications. A standard cascaded multilevel inverter requires n DC
sources for 2n+1levels at the output, where n is the number of inverter stages. This paper presents a topology to
control cascaded multilevel inverter that is implemented with multiple DC sources to get 2"+1_ 1 levels. Without
using Pulse Width Modulation (PWM) technique, the firing circuit can be implemented using Microcontroller
which greatly reduces the Total Harmonic Distortion (THD) and switching losses. To develop the model of a
cascaded hybrid multilevel inverter, a simulation is done based on MATLAB/SIMULINK software and
hardware implementation was also done. Their integration makes the design and analysis of a hybrid multilevel
inverter more complete and detailed.
A Single Phase Eleven Level Cascaded H-Bridge Multilevel Inverter for Photovo...IJMER
Abstract: A Cascaded H-Bridge Multilevel Inverter is a power electronic converter built to synthesize a desired ac voltage
from several levels of dc voltages with better harmonic spectrum. Such inverters are suitable for high voltage and high
power applications and have been an important development in recent years. This paper presents the performance of a
eleven level cascaded H-Bridge multilevel inverter topology with multicarrier pulse width modulation technique for
photovoltaic cell. This inverter is capable of producing eleven levels of output voltage from the dc supply voltage. This
topology magnifies the fundamental output voltage with reduction in total harmonic distortion . The output is drawn near the
sine wave because of more levels. It can also be easily extended to an m-level inverter. The performance of the proposed
PWM strategy in terms of output voltage and THD is shown using MATLAB/Simulink.
Keywords: Multilevel inverter, Cascaded H-Bridge multilevel inverter, Multicarrier pulse width modulation, PV cell, Total
harmonic distortion.
Comparative analysis of multilevel inverter topologies for induction motor dr...eSAT Journals
Abstract Induction motors are widely used in industries, because they are rugged, reliable and economical and hence they are called as work horse power of industry. Induction motor drive requires suitable converters to get the required speed and torque without or negligible ripples. Multilevel inverters can do this job. But the conventional MLIs such as Diode Clamped MLIs requires extra diodes in conjunction with the active switches, Flying capacitor MLIs requires extra Capacitors and control also difficult if the levels increases and the Cascaded H-bridge MLIs requires separate dc sources which limits its use. This paper proposes a new type of multi level Inverter which converts the dc into ac using less number of switches when compared to conventional multilevel Inverters. The proposed Inverter uses only seven switches to get 13-level output voltage compared conventional cascaded H-bridge uses twelve switches. The comparison between the conventional MLIs and proposed inverter is presented in this paper. Finally the induction motor using proposed inverter with thirteen level is simulated using Matlab/Simulink environment and the corresponding results are presented in this paper. Keywords- Grid interconnection, PV system, MLI, Renewable energy sources (RES).
Analysis of Impedance Source Inverter Topologies for Grid Integration of PV I...IJPEDS-IAES
In this paper, the performance of different Impedance Source Inverter (ZSI)
topologies in implementing single stage power conversion for grid
ingetertion of PV power converters is discussed. Unlike the traditional
inverters, ZSI employs a distinctive impedance network, there by making
shoot-through state is possible. The independent control variables are shootthrough
duty ratio and modulation index. Simple Boost Control pulse width
modulation technique was used in this work to vary the modulation index.
Here the basic operation, simple boost control method, characteristics,
requirements and harmonic analysis of the classical Z-Source Inverter (ZSI),
TZ-Source Inverter (TZSI), Trans-Z-Source Inverter (Trans-ZSI) and
Improved ZSI (IMZSI) topologies were compared for interfacing the wide
range variable input energy to utility supply system. The performances were
compared based on its MATLAB/SIMULINK simulation model and featured
results are shown to confirm its validity.
Implementation of Cascaded H-bridge MULTI-LEVEL INVERTEREditor IJMTER
The classical two level inverter produce output with levels either Vdc or -Vdc. The output
voltage waveform of ideal inverter should be sinusoidal but the waveform of conventional inverters
is non-sinusoidal and contains certain harmonics. Large capacitor is normally connected across the
DC voltage source and such a capacitor is costly and demands space. In order to overcome these
drawbacks Multi level inverters are introduced. The great advantage of this kind of inverter is the
minimum harmonic distortion obtained. Power electronics is the applications of power
semiconductor devices for the control and conversion of electric power such that these devices
operate as switches. An inverter is an electrical device that converts DC voltage to AC voltage; the
resulting AC can be at any required frequency. Multi-level inverters are nothing but the modification
of basic bridge inverters [1]. The multilevel inverter collectively converts the several levels of dc
voltage to a desired ac voltage. The unique structure of multilevel inverters allows them to reach
nearer to sinusoidal i.e., with low harmonics. In this project the work is done on five & nine level
multilevel inverter but the multilevel can be done up to any level and how many levels we increase
that much precise sinusoidal supply we can get i.e., we can reduce that many harmonics from the
supply. Simulation work is done using the MATLAB software
it is the most simplest presentation which is easy for preparetion and presentation.if u want some more information about multilevel inverter then follow the link given below
https://www.theengineeringprojects.com/2014/12/introduction-multilevel-inverters.html
Comparison of Sine and Space Vector Modulated Embedded Z-Source Inverter fed ...IAES-IJPEDS
This paper deals with performance of photovoltaic powered Embedded
Z-Source Inverter (EZSI) fed Induction motor drive. The DC output from the
PV-Panel is boosted and converted into AC using Embedded Z-Source
Inverter. EZSI system based on the concept of Z-Source Inverter (ZSI),
which provides single stage power conversion. The EZSI also produce same
voltage gain as that of the ZSI based system. In EZSI the DC source is
embedded within the X-shaped LC impedance network, due to this EZSI has
the added advantage of inherent source filtering capability, this can be
achieved without any extra passive filter. EZSI can produce the AC output
voltage which is greater than the DC link voltage. EZSI system also provides
ride-through capability under voltage sags. In this paper the performance of
space vector modulated EZSI fed Induction Motor Drive is compared with
sinusoidal PWM controlled EZSI fed Drive system. The PV powered EZSI
fed three phase Induction Motor System is designed, modeled and simulated
using MAT LAB-SIMULINK and the corresponding results are presented.
This drive system has advantages like voltage boosting ability and reduced
harmonic content.
Performance and Analysis of Hybrid Multilevel Inverter fed Induction Motor Drivernvsubbarao koppineni
This paper presents the Five level inverter with single DC source which is used to generate a five level output with two bridges and six switches and performance of three phase induction motor is analyzed when connected to PV array For this two identical dc sources of 50V each for two bridges in five levels using Multi level inverter and five level output is obtained by using a single DC source of 100V with six switches. A virtual DC source (charged capacitor acts as virtual DC source) is used for getting the output. The same technique is implemented for three-phase circuit i.e. by using single DC source. An asynchronous motor (three-phase) is connected as load and its performance characteristics are analyzed. And further the DC source is replaced by a renewable resource such as solar panels, fuel cell etc. and DC voltage is obtained. Performance characteristics of three-phase asynchronous motor are analyzed with PV array connected. The method can be easily extended to an m-level inverter.
An Improved the High Voltage Boost Inversion Ability of Switched Inductor Qua...IJSRD
This paper presents an improved the high voltage boost inversion ability of switched inductor quasi ZSI by using Boost PWM technique. This presents a comparative analysis of Boost Inversion Ability of Switched Inductor Quasi z-source inverter (SL-QZSI) with conventional z-source Inverter (ZSI). In comparison to conventional ZSI for the same value of voltages in the input and output the proposed SL-QZSI provides the less count on passive component a dc-source with common ground less voltage across the capacitors it gives the continuous input current current shoot through is reduced and also the current stress across the inductor and diodes are reduced. This thesis presents the operating principle boost inversion ability analysis simulation results and comparison of conventional ZSI with SLQZSI The simulation results confirmed the ability of high step up inversion by this proposed SL-QZSI. An extended switched inductor quasi z-source inverter (ESL-QZSI) with high boost voltage inversion ability is presented which combines the SL-QZSI with the traditional boost converter as well as improves the switched-inductor cell. Compared with the classic SL-QZSI topologies the proposed topology reduces the voltage stresses of capacitors power devices and diodes for the same input. The operation principle of the proposed topology is analyzed in detail. In addition, the performance of the proposed topology is verified by simulations and experiments.
Analyses of reactive power compensation schemes in MV/LV Networks with RE infeedAushiq Ali Memon
-Reactive power compensation in MV/LV Networks
-Voltage control with renewable energy infeed
- Power factor correction with reactive power compensation schemes (SVC and STATCOM)
-DFIG wind turbine grid-code requirements according to bdew standard.
Injection of the wind power into an electric grid affects the power quality. The performance of the wind turbine and thereby power quality are determined on the basis of measurements and the norms followed according to the guideline specified in International Electro-technical Commission standard, IEC-61400. The influence of the wind turbine in the grid system concerning the power quality measurements are-the active power, reactive power, variation of voltage, flicker, harmonics, and electrical behavior of switching operation and these are measured according to national/international guidelines. The paper study demonstrates the power quality problem due to installation of wind turbine with the grid. In this proposed scheme STATic COMpensator (STATCOM) is connected at a point of common coupling with a battery energy storage system (BESS) to mitigate the power quality issues. The battery energy storage is integrated to sustain the real power source under fluctuating wind power. The STATCOM control scheme for the grid connected wind energy generation system for power quality improvement is simulated using MATLAB/SIMULINK in power system block set. The effectiveness of the proposed scheme relives the main supply source from the reactive power demand of the load and the induction generator. The development of the grid co-ordination rule and the scheme for improvement in power quality norms as per IEC-standard on the grid has been presented.
Powerpoint Search Engine has collection of slides related to specific topics. Write the required keyword in the search box and it fetches you the related results.
This paper proposed a new sparce matrix converter with Z-source network to provide unity voltage transfer ratio. It is an ac-to-ac converter with diode-IGBT bidirectional switches. The limitations of existing matrix converter like higher current THD and less voltage transfer ratio issues are overcome by this proposed matrix converter by inserting a Z-source. Due to this Z-source current harmonics are totally removed. The simulation is performed for different frequencies. The simulation results are presented to verify the THD and voltage transfer ratio and compared with the existing virtual AC/DC/AC matrix converter. The experimental output voltage amplitude can be varied with the variable frequencies.
This paper proposes the use of Embedded EZ-source
inverter system (EZSI) as a single stage power conversion
concept for adjustable speed drives (ASD) in photovoltaic
applications. Open loop and closed loop control strategy of
EZSI system are proposed. EZSI produces the same voltage
gain as Z-source inverter (ZSI) but due to the DC sources
embedded within the X- shaped impedance network, it has
the added advantage of inherent source filtering capability
and also reduced capacitor sizing. This is attained without
any extra passive filters. By controlling the shoot-through
duty ratio and modulation index, EZSI system can produce
any desired AC output voltage even greater than DC rail
voltage and it also provides ride-through capability under
voltage sag. These advantages are more significant for
adjustable speed drive (ASD) applications in order to regulate
the speed. The operational analysis, control strategy and
simulation results exemplify that an EZSI is the most
promising technique for renewable energy applications in
order to reduce the overall system complexity and thereby
improving the inverter efficiency.
Comparative Evaluation of Generalized Multicell Impedance Source Inverter for...IJPEDS-IAES
Voltage-Source Inverter is limited by its only voltage step-down operation. In adding with extra boosting the flexibility is kept active for the number of semiconductors which is unchanged, voltage-type Z-source inverter was earlier proposed. This new class of inverter is generally less sensitive to electromagnetic noises. However, their boosting capabilities are anyhow less with high component stresses and poorer spectral performances caused by low modulation index ratios. Their boosting gains are, therefore, restricted in practice. To overcome these we use the generalized switched-inductor Z- source inverter is proposed, By comparing with PWM technique and SPWM technique, whose extra boosting abilities and other advantages have been verified in simulation analysis and experiment.
A Comparative Study of Various AC-DC Converters for Low Voltage Energy Harves...paperpublications3
Abstract: Electromagnetic microscale and mesoscale power generators with low voltage outputs are now widely used as kinetic energy harvesters. The extrinsic vibrations on the generator can excite the internal oscillations between the proof mass magnet and the electrical damper coils. These oscillations produce a periodically varying magnetic flux in coil, inducing a corresponding AC output voltage. This output can be converted to dc and can be used to supply power to electronic loads. The conventional AC-DC converters for energy harvesting system with diode rectifiers suffer considerable voltage drop resulting increase in power loss of circuitry and complexity. As a remedy various bridgeless boost converters were designed and implemented. Standard H bridge converter with 4 switch or 2 switch, dual polarity boost converters, parallel combination of boost and buck-boost converter, integrated boost and buck-boost combination bridgeless rectifier are some of these. These circuits are studied, simulated and compared. The simulation models are drawn and simulated using MATLAB R2010a.
Proposed Method for Shoot-Through in Three Phase ZSI and Comparison of Differ...IAES-IJPEDS
This paper presented the new methodology for different control techniques applied to three phase Z-source inverter for minimisation of switching losses. The procedure for proposed control techniques and its effects on the performance of operation of three phase Z-source inverter are analyzed. The graphs for voltage gain and voltage stress are drawn for different control methods. The flow-chart for the symmetrical and unsymmetrical control techniques for creating pulse signals for switches of three phase inverter are shown. All the methods are studied and compared with each other. The Total harmonic distortion (THD) of output voltage of both the control methods has been analyzed using FFT analysis. The experiments done and the results shown for capacitor voltage, load current and load line voltage for simple boost and constant boost control techniques are presented using MATLAB/ Simulink.
The International Journal of Engineering and Science (The IJES)theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Power quality improvement using impedance network based invertereSAT Journals
Abstract Inverters are suited for applications where DC supply is converted to AC signal with desired waveform & adequate quality of power. Recently proposed Trans Z –source inverters and T –source inverters characterize improved power quality with the help of coupled inductors with turn’s ratio higher than one. This paper presents the concept of LC network based inverter. The built in DC current blocking capacitors connected in series with transformer windings and therefore prevent the transformer core from saturation. The novel LC network based inverter topology proposed in this paper characterize available continuous input current which is the advantage compared to TZSI and TSI. Simulations have been carried out in PSIM platform and results are presented to validate the proposed topology of the inverter system. Index Terms: Power quality, LC network, Impedance source inverter, Boost control, Shoot through state.
Power quality improvement using impedance network based invertereSAT Publishing House
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.
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.
Design of Three-Phase Three-Switch Buck-Type Rectifier for Pre-Charging Appli...IAES-IJPEDS
The main objective of a pre-charging circuit in variable frequency drives is to
pre-charge the DC-bus capacitor without any voltage and current overshoot
within the specified time. In exisiting variable frequency drives seperte precharging
circuits (or) thyristor bridges were used due to this drives power
density, cost becomes high and control technique becomes complex. This
paper presents about the design of three-phase three-switch buck-type
rectifier for pre-charging application used in variable frequency drives which
elimates the disadvantages of existing techniques. In this paper we will
discuss about design procedure of pre-charging circuit of an 800KW
converter with dc-link output voltage of 775V at an input ac voltage of 550V,
60Hz, selection of power and passive components, voltage and current stress
of power transistors. In the final this paper discusses about loss distribution
of the components and comparison of new converter technique with existing
pre-charging techniques.
A DC Inrush Current Minimisation Method using Modified Z-Source Inverter in A...IAES-IJPEDS
The adjustable speed drives employ PWM converter-inverter system in order
to obtain unity power factor. The DC inrush current in DC link capacitors of
the rectifier limits the operation of power devices. Hence, this paper proposes
a new approach to reduce the DC inrush current by employing modified
Z-source inverter in a Adjustable Speed Drive system. The operating
principles, design procedure and simulation results are shown and compared
with the conventional Z-Source inverter.
Proposed impedance network also has more degrees of freedom for varying its voltage gain, and hence, improving the versatility of the inverter. A switching algorithm is applied to this topology to control the charging time and discharging interval of inverter inductor. Methods/Statistical Analysis: On the basis of the conventional Z-source inverter[ZSI], this paper offer a novel on new type impedance source inverter which only contains one capacitor with tightly coupled three winding transformer, whose obtained voltage gain is presently not matched by existing networks operated at small duty ratio. The inverter can increase the boost factor through adjusting shoot-through duty ratio and varying the number of turns in the three winding transformer. Findings: The proposed impedance network also has more degrees of freedom for varying its voltage gain, and hence, improving the versatility of the inverter. A switching algorithm is applied to this topology to control the charging time and discharging interval of inverter inductor. A simple control strategy is applied to this configuration which is responsible for regulating the transfer power to the maximum amount and also to justify the amount of Total Harmonic Dissortion (THD) in minimum point. The working principle of the proposed Y-Source Inverter has been demonstrated by mathematical analysis in detail. The MATLAB/Simulink Simulation results are conducted to validate the
Similar to Simulation of SPWM based Z-Source Inverter (20)
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
NUMERICAL SIMULATIONS OF HEAT AND MASS TRANSFER IN CONDENSING HEAT EXCHANGERS...ssuser7dcef0
Power plants release a large amount of water vapor into the
atmosphere through the stack. The flue gas can be a potential
source for obtaining much needed cooling water for a power
plant. If a power plant could recover and reuse a portion of this
moisture, it could reduce its total cooling water intake
requirement. One of the most practical way to recover water
from flue gas is to use a condensing heat exchanger. The power
plant could also recover latent heat due to condensation as well
as sensible heat due to lowering the flue gas exit temperature.
Additionally, harmful acids released from the stack can be
reduced in a condensing heat exchanger by acid condensation. reduced in a condensing heat exchanger by acid condensation.
Condensation of vapors in flue gas is a complicated
phenomenon since heat and mass transfer of water vapor and
various acids simultaneously occur in the presence of noncondensable
gases such as nitrogen and oxygen. Design of a
condenser depends on the knowledge and understanding of the
heat and mass transfer processes. A computer program for
numerical simulations of water (H2O) and sulfuric acid (H2SO4)
condensation in a flue gas condensing heat exchanger was
developed using MATLAB. Governing equations based on
mass and energy balances for the system were derived to
predict variables such as flue gas exit temperature, cooling
water outlet temperature, mole fraction and condensation rates
of water and sulfuric acid vapors. The equations were solved
using an iterative solution technique with calculations of heat
and mass transfer coefficients and physical properties.
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
CW RADAR, FMCW RADAR, FMCW ALTIMETER, AND THEIR PARAMETERSveerababupersonal22
It consists of cw radar and fmcw radar ,range measurement,if amplifier and fmcw altimeterThe CW radar operates using continuous wave transmission, while the FMCW radar employs frequency-modulated continuous wave technology. Range measurement is a crucial aspect of radar systems, providing information about the distance to a target. The IF amplifier plays a key role in signal processing, amplifying intermediate frequency signals for further analysis. The FMCW altimeter utilizes frequency-modulated continuous wave technology to accurately measure altitude above a reference point.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
Contact with Dawood Bhai Just call on +92322-6382012 and we'll help you. We'll solve all your problems within 12 to 24 hours and with 101% guarantee and with astrology systematic. If you want to take any personal or professional advice then also you can call us on +92322-6382012 , ONLINE LOVE PROBLEM & Other all types of Daily Life Problem's.Then CALL or WHATSAPP us on +92322-6382012 and Get all these problems solutions here by Amil Baba DAWOOD BANGALI
#vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore#blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #blackmagicforlove #blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #Amilbabainuk #amilbabainspain #amilbabaindubai #Amilbabainnorway #amilbabainkrachi #amilbabainlahore #amilbabaingujranwalan #amilbabainislamabad
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...
Simulation of SPWM based Z-Source Inverter
1. IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE)
e-ISSN: 2278-1676,p-ISSN: 2320-3331, Volume 6, Issue 3 (May. - Jun. 2013), PP 53-60
www.iosrjournals.org
www.iosrjournals.org 53 | Page
Simulation of SPWM based Z-Source Inverter
N.Muruganandham1
, G.Lavanya2
,R.Satheesh Babu3
1,3
(Project Engineer/ Aeon Automation Solutions, Chidambaram, Tamilnadu, India)
2
(Assistant Professor, Department of EEE, IFET College of Engineering, Villupuram, Tamilnadu, India)
Abstract : This paper presents a single stage Z-source inverter (ZSI) that can either buck or boost the ac output
voltage from a DC supply. This topology overcomes the short comings of the where the output ac voltage is
either less or more than the input dc voltage. The ZSI also allows two switches of the same leg to be gated in the
circuit thus eliminating the shoot through fault that normally occurs in the traditional converters. This feature
of the inverter provides the elimination of dead time in the circuit, thus increasing the reliability and reducing
the output distortion. To prove the effectiveness of ZSI in reducing THD, performance of ZSI is evaluated using
MATLAB/SIMULINK model developed for ZSI feeding R, RL, Motor load. The simulation results are presented
for various modulation indexes and compared with the simulation results of VSI and CSI. The results validate
the effectiveness of ZSI over VSI and ZSI.
Keywords -Current source inverter, voltage source inverter, Z-source inverter, SPWM, THD.
I. INTRODUCTION
An inverter is a class of power conversion circuits that operates from a dc voltage source or a dc
current source and converts it into ac voltage or current. Depending upon the sources inverters are classified into
three namely, current source inverter, voltage source inverter and impedance source inverter [1-2]. To overcome
the conceptual and theoretical barriers and limitation of the traditional voltage source inverter and current source
inverter an impedance source power converter is developed. Z-source inverter is an impedance network which
links the converter main circuit to the load or other converter, it is for providing special feature is not available
in the traditional voltage source and current source inverter in which capacitor or inductor is used [3]. The main
exposure of the Z- source inverter is that it can overcome the limitation of the traditional converters. A Z-source
converter can provide unique features that cannot be obtained in traditional voltage–source and current–source
converters. Recently, the research on Z-source has mainly focused on the three-phase Z-source inverter in which
the Z-source network is used as the front stage [4]–[6]. The battery is paralleled with the Z-source capacitor in
the three-phase Z-source inverter proposed in [7-9], and the Z-source network also performs the voltage boost
ability as the front stage.
In this paper, a single-phase Z-source inverter topology is presented based on the unique feature of the Z-
source. The feasibility of the proposed topology sinusoidal pulse width modulation strategy is analyzed in detail
and verified by simulation and the results are compared with current source and voltage source inverters.
II. SINGLE PHASE VOLTAGE SOURCE INVERTER
Fig.1 shows such circuit where a single dc supply has been split in two halves. In such circuits the
voltages across the two capacitors may not remain exactly balanced due to mismatch in the loading patterns or
mismatch in leakage currents of the individual capacitors. Also, unless the capacitors are of very large
magnitude, there may be significant ripple in the capacitor voltages, especially at low switching frequencies.
Fig.1 Topology of single phase voltage source inverter
These topologies require only a single dc source and for medium output power applications (‘Vi’ is the input dc
supply and) a large dc link capacitor (Cdc) is required across the supply terminals. Capacitors and switches are
2. Simulation of SPWM based Z-Source Inverter
www.iosrjournals.org 54 | Page
connected to dc bus using short leads to minimize the stray inductance between the capacitor and the inverter
switches.
In the voltage source inverter the voltage remains constant with variations in the load. It is capable of
supplying variable voltage for speed control of induction motor. Both the switches S1 and S2 or S3 and S4 cannot
be simultaneously operated because short circuit across the dc link voltage Vi would be produced. There are four
defined and one undefined state. The undefined state is avoided, in order to avoid the short circuit across the dc
bus and the undefined ac output voltage condition. The modulating technique should ensure that either the top or
the bottom switch of each leg is on at any instant. It can be observed that the ac output voltage can take values
up to the dc link value Vi. Several modulating techniques have been developed that are applicable to the VSIs.
Among them sinusoidal PWM technique is considered for VSI.
III. SINGLE PHASE CURRENT SOURCE INVERTER
The circuit of a Single-phase Current Source Inverter (CSI) is shown in Fig. 2. A constant current
source is assumed here, which may be realized by using an inductance of suitable value, which must be high, in
series with the current limited dc voltage source. The thyristor pairs, Th1& Th3, and Th2& Th4, are alternatively
turned ON to obtain a nearly square wave current waveform. Two commutating capacitors -C1in the upper half,
and C2in the lower half, are used. Four diodes, D1-D4are connected in series with each thyristor to prevent the
commutating capacitors from discharging into the load. The output frequency of the inverter is controlled in the
usual way, i.e., by varying the half time period, (T/2), at which the thyristor in pair are triggered by pulses being
fed to the respective gates by the control circuit, to turn them ON. The inductance (L) is taken as the load in this
case, the reason(s) for which need not be stated, being well known.
Fig.2 single phase current source inverter topology
At time, t = 0, thyristor pair, Th1& Th3, is triggered by pulses at the gates. The conducting thyristor
pair, Th2&Th4, is turned OFF by application of reverse capacitor voltages. Now, thyristor pair, Th1& Th3,
conducts current (I). The current path is through Th1, C1, D1, Load, C2, D3, Th3, and source, I. Similarly the
when the thyristor pairs, Th2 &Th4, is triggered by the pulses at the gates. The conducting thyristor pair
Th1&Th3 is turned OFF by the application of reverse capacitor voltages. Now, thyristor pair, Th2 & Th4,
conducts current (I). The current path is through T2, D2, C1, Load, C2, D4, T4. The output frequency of the
inverter is controlled in the usual way, i.e., by varying the half time period, (T/2), at which the thyristor in pair
are triggered by pulses being fed to the respective gates by the control circuit, to turn them ON. The R, RL,
Motor load is considered for analyzing the performance of the given CSI.
IV. SINGLE PHASE Z-SOURCE INVERTER
A unique impedance network is used in the Z-source inverter that consists of two identical inductors L1
and L2 along with two identical capacitors C1 and C2 that couples the power supply to the inverter circuit. The
shoot through period ie, the time period when the switch S1 in fig 3(b) is gated allowing the voltage to be
boosted to the required values when the input dc voltage is not up to the required level. Else otherwise the shoot
through states is not used thus enabling the ZSI to operate as both a buck-boost inverter unlike the traditional
VSI and CSI. Fig 3 shows the presence of the Z-source impedance network preceding the switch S2 and
succeeding switch S1. There are two basic Z-source converter topologies [10], including voltage fed and current
fed, as shown in Fig. 3(a) and 3b).
LOAD
Th1 Th2
Th3Th4
D1 D2
D3D4
I
I
I
C1
C2
3. Simulation of SPWM based Z-Source Inverter
www.iosrjournals.org 55 | Page
Fig. 3 (a) Voltage fed Z- source converter Fig. 3 (b) Current fed Z- source converter
The Z-source networks are symmetric in these topologies. S1and S2are turned on and off in
complement. Defining the duty ratio of S1as D, we can then get the relationship between voltage ratio and D of
the voltage-fed and current-fed topologies, respectively, as
Vo
Vi
=
D
2D − 1
.
Vo
Vi
=
2D − 1
D − 1
(1)
For the voltage-fed topology, it clearly shows that there are two discontinuous operation regions. For the
current-fed topology, we can see that the output voltage varies continuously. When D is less than 0.5, the output
voltage is in phase with the input voltage. When D is greater than 0.5, the output voltage is out of phase with the
input voltage.Fig. 4 (a) shows the basic single-phase Z-source inverter topology. Vi= VCcan be derived easily in
steady state from Fig. 4(a); then we can get the improved topology with input and output sharing the same
ground, as shown in Fig. 4(b).
(a) (b)
Fig. 4(a) Basic topology of Single-phase Z-source inverter, (b) Improved topology of Single-phase Z-source
inverter
The unsymmetrical Z-source network is composed of input voltage source Vi , capacitor C1 C2, and inductors
L1andL2, where L1and L2can be coupled with required coupling factor.
V. OPERATING PRINCIPLE OF SINGLE PHASE Z-SOURCE INVERTER
The duty ratio of S1 is D and the coupled inductor of L1 and L2 is M. Two states exist in one switching period, and
Fig.4 shows their equivalent circuits.
(a) (b)
Fig. 5. Equivalent circuits in one switching period (a) State 1. (b) State 2.
S1 L1
C1
L2
R Cf
Vin
S2
4. Simulation of SPWM based Z-Source Inverter
www.iosrjournals.org 56 | Page
In state 1, switch S1 is turned on and S2 is turned off. The time interval in this state is DT, where T is
the switching period, as shown in Fig. 5(a). For active state of the switch S1 the voltage induced in the inductors
L1 and L2 are represented as
L1
diL1
dt
+ M
diL2
dt
= vi − vo
L2
diL2
dt
+ M
diL1
dt
= vc − vo
C
dvc
dt
= −iL2
Cf
dvo
dt
= iL1 + iL2 − io
(2)
In state 2, S2 is turned on and S1 is turned off. The time interval in this state is (1–D)T, as shown in
Fig. 5(b). .For active state of the switch S2 the voltage induced in the inductors L1 and L2 are represented as
L1
diL1
dt
+ M
diL2
dt
= −vc
L2
diL2
dt
+ M
diL1
dt
= −vi
C
dvc
dt
= iL1
Cf
dvo
dt
= −io
(3)
From (2) and (3), we can get the averaged equation
L1
diL1
dt
+ M
diL2
dt
= D(vi − vo) − (1 − D)vc
L2
diL2
dt
+ M
diL1
dt
= D(vc − vo) − (1 − D)vi
C
dvc
dt
= −DiL2 − (1 − D)iL1
Cf
dvo
dt
= D(iL1 + iL2) − io
(4)
In steady state, we get
Vc = Vi
Vo
Vi
=
2D − 1
D
iL1 = io
iL2 =
1 − D
D
iL1
(5)
In the traditional three-phase Z-source inverter, the Z-source network works in the half region (D <0.5)
to perform only voltage boost conversion. The proposed topology performs an unsymmetrical characteristic. As
can be derived from (5), when D <0.5, the converter performs the buck–boost conversion and the polarity of
output is inverse. When D >0.5, the converter performs only the buck conversion and the polarity of output is
the same. As we know, a small D will cause parasitic effects to be more prominent and degrade the inverter
performance. The chosen topology, it performs as a buck inverter when D is varied from 1/3 to 1. D is always
greater than 1/3, so the parasitic effects are not prominent. Equation (5) also infers that unbalance of iL1and iL2is
related to D. To perform the dc–ac conversion, D is varied between 1/3 and 1
5. Simulation of SPWM based Z-Source Inverter
www.iosrjournals.org 57 | Page
VI. Sinusoidal Pulse Width Modulation
SPWM is one of the most popular and simple methods utilized in power inverter and motor control
fields. Its main features can be summarized as sine-triangle wave comparison. As shown in Fig.6, a sine wave
(modulated wave) is compared with a triangle wave (carrier wave) and when the instantaneous value of the
triangle wave is less than that of the sine wave, the PWM output signal is in high level (1). Otherwise it is turned
into the low level (0). The level switching edge is produced at every moment the sine wave intersects the
triangle wave. Thus the different crossing positions result in variable duty cycle of the output waveform. Sine
and triangle waves are respectively generated by specially designed circuits and then fed to the properly selected
comparator which can output the desired SPWM signal.
Fig.6. Sinusoidal pulse width modulation for proposed system
VII. Simulation Results
Fig.7. Simulink of Voltage source inverter with R-Load
Fig.8. Simulink of Current source inverter with RL- Load
Discrete,
Ts = 5e-05 s.
powergui
v+
-
G1
gm
DS
S4
gm
DS
S3
gm
DS
S2
gm
DS
S1
+
R load
Sinusoidal PWM Generator
Load
Voltage
Load
Current
G4
G3
G2
G4
G2
G3
G1
DC
i
+ -
Output Voltage
Load Current
Discrete,
Ts = 5e-05 s.
powergui
v
+
-
v+
-
v
+
-
Switching
Pulse Generator
mM+
M
capacitor
-start
Tm
Single Phase
Asynchronous Machine
+
+
+
Seri4
+
Seri3
+
+
+
Seri
Scope6
Scope3
Scope2
Scope1
NOT
g
C
E
g
C
E
Vc
Goto1
V0
i+ -
i
+ -
i+
-
1
Constant <Main winding current Ia (A or pu)>
<Auxiliary winding current Ib (A or pu)>
2
Out3
1
Out1Sine Wave
Repeating
Sequence
>
Relational
Operator1
>
Relational
Operator
Load
Voltage2
-1
Gain
6. Simulation of SPWM based Z-Source Inverter
www.iosrjournals.org 58 | Page
Fig.9. Simulink of Z- source inverter with Motor-Load
Fig.10. Output Voltage of VSI, CSI and ZSI for various Load conditions
Discrete,
Ts = 5e-05 s.
powergui
v+
-
Sine PWM Generator
gm
DS
S4
gm
DS
S3
gm
DS
S2
gm
DS
S1
+
RL Load
+
+
Load
Voltage
Load
Current
+
Li
Inductor Current
G4
G3
G2
G1G4
G2
G3
G1
Diode3
Diode2
Diode1
Diode
DC
i+ -
i
+ -
7. Simulation of SPWM based Z-Source Inverter
www.iosrjournals.org 59 | Page
Fig.11. FFT analysis of VSI, CSI and ZSI for various Load conditions
Table.1. % Total Harmonic Distortion for RL load
Modulation Index
(ma)
% THD for RL Load
Voltage Source Inverter (VSI) Current Source Inverter (CSI) Z- Source Inverter (ZSI)
1.0 47.90 10.42 10.23
0.9 78.47 11.78 10.23
0.8 127.81 12.43 10.23
0.7 269.05 14.21 10.23
0.6 981.25 14.71 10.23
Table.2. % Total Harmonic Distortion for Motor load
Modulation Index
(ma)
% THD for Motor Load
Voltage Source Inverter (VSI) Current Source Inverter (CSI) Z- Source Inverter (ZSI)
1.0 47.91 74.03 11.11
0.9 56.78 65.79 11.11
0.8 96.23 66.14 11.11
0.7 156.12 93.99 11.11
0.6 3851.25 170.71 11.11
8. Simulation of SPWM based Z-Source Inverter
www.iosrjournals.org 60 | Page
VIII. Conclusion
Conventional single-phase inverter topologies cannot achieve a common ground between the input and
output, so they cannot be used in conditions where dual grounding is needed. To solve this problem, a novel
single-phase Z-source inverter topology with an inherent common ground for input and output has been given.
The operation principle and sinusoidal pulse width modulation control strategy are analyzed in detail and
verified by simulation results. The results were compared with Voltage and Current Source Inverter, and it is
observed that THD are relatively less in ZSI when compared with VSI and CSI.
REFERENCES
[1] N. V azquez, J. Almazan, J.Alvarez, C. Aguilar, and J. Arau, Analysis and experimental study of the buck, boost and buck-boost
inverters,in Proc. IEEE PESC, Charleston, SC, 1999, 801–806.
[2] Y. S. Xue, L. C. Chang, and S. B. Kjær, Topologies of single-phase inverters for small distributed power generators: An overview,
IEEE Trans. Power Electron.,19(5), 1305–1314, 2004.
[3] N. Kasa, T. Iida, and H. Iwamoto, An inverter using buck-boost type chopper circuits for popular small-scale photovoltaic power
system,in Proc. IEEE IECON, San Jose, CA, 1999,185–190.
[4] F. Z. Peng, Z-source inverter, IEEE Trans. Ind. Appl., 39(2), 504–510, 2003.
[5] M. S. Shen, J.Wang, A. Joseph, F. Z. Peng, L. M. Tolbert, andD. J.Adams, Constant boost control of the Z-source inverter to
minimize current ripple and voltage stress,IEEE Trans. Ind. Appl., 42(3), 770–777, 2006.
[6] P. C. Loh, D. M.Vilathgamuwa,Y. S. Lai, G. T. Chua, and Y.W. Li, Pulsewidth modulation of Z-source inverters,IEEE Trans. Power
Electron., 20(6), 1346–1355, 2005.
[7] M. S. Shen and F. Z. Peng, Control of the Z-source inverter for fuel cell-battery hybrid vehicles to eliminate undesirable operation
modes, in Proc. IEEE IAS, 2006, 1667–1673.
[8] K. M. Smedley and S. Cuk, One-cycle control of switching converters,IEEE Trans. Power Electron., 10,(6), 625–633,1995.
[9] K. M. Smedley and S. Cuk, Dynamics of one-cycle controlled Cuk converter,IEEE Trans. Power Electron., 10, (6), 634–639,1995.
10] X. P. Fang, Z. M. Qian, and F. Z. Peng, Single-phase Z-source PWM AC-AC converters,IEEE Power Electron. Lett., 3(4),121–124,
2005.