This document describes a proposed three-phase isolated boost DC-DC converter for high voltage applications. Some key points:
1. The converter uses a Delta-Wye transformer connection to reduce the transformer turn ratio by half, addressing issues with high turn ratios like large leakage inductance.
2. A clamp circuit clamps surge voltages and reduces circulating currents, lowering conduction losses.
3. The converter achieves zero-voltage switching for all switches over a wide load range without affecting duty cycle, improving efficiency.
4. Simulation results validate the operating principles and features, making the converter well-suited for applications like electrolyzers that require high step-up voltage conversion.
This document summarizes a research paper that proposes and evaluates a novel interleaved ZCS boost DC-DC converter topology for photovoltaic interfaces. The converter uses two quasi-resonant switch blocks and lossless snubbers to achieve soft switching. Simulation results show the converter achieves reduced voltage and current ripple compared to conventional designs. A dual loop control scheme with an outer voltage loop and inner current loop is used to regulate the output. Coupling inductors between converter cells further improve transient response and reduce ripple. The proposed converter design and control scheme effectively interfaces photovoltaic systems with loads.
Voltage Control of Dual Active Bridge Converter for CO-Amorphous Core Materia...kuldeep12555
Solid-State Transformer (SST) provides versatile power system operation. In the smart world, there are technologies where everything is incorporated that reduce the size and eventually save time in delivering a fast process. It has been seen that solid-state transformer voltage begins to decrease during operation that needs to be regulated through some control strategy. In this paper, a Dual Active Bridge (DAB) converter has been used to control the voltage of SST that employs the Single-Phase Shift (SPS) technique. For further efficiency improvement Co73(Si, B)27 co-amorphous material has been used for the core of SST because co-amorphous alloy has much lower loss compared with Fe-amorphous cores and have limited saturation flux density. Real-time parameters of core have been used in the analysis. It has been evident from the results that DAB dc-dc converter-based SST with SPS control technique is simple and offers better performance compared to stand-alone SST. It improves the overall performance and efficiency of the system. This paper has been accomplished in Matlab® / Simulink environment.
Keywords: Co73 (Si, B)27 Amorphous Core Material; Solid-State transformer (SST); Dual Active Bridge (DAB); High
voltage (HV) Application.
An Asymmetrical Dc-Dc Converter with a High Voltage GainIJMER
An asymmetrical full bridge converter is proposed in the paper. The proposed converter
achieves zero voltage switching of all the power switches. Zero current switching of all the output diodes
are also achieved here. This in turn provides a highly efficienct operation. The proposed converter can
provide a high voltage gain and the voltages across the semi- conductor devices are effectively clamped.
The converter can be utilised effectively in high voltage applications as embedded systems, renewable
energy systems, fuel cells, mobility applications and uninterrupted power supply
This paper proposes a non-isolated soft-switching bidirectional dc/dc converter for interfacing energy storage in DC microgrid. The proposed converter employs a half-bridge boost converter at input port followed by a LCC resonant tank to assist in soft-switching of switches and diodes, and finally a voltage doubler circuit at the output port to enhance the voltage gain by two times. The LCC resonant circuit also adds a suitable voltage gain to the converter. Therefore, overall high voltage gain of the converter is obtained without a transformer or large number of multiplier circuit. For operation in buck mode, the high side voltage is divided by half with capacitive divider to gain higher step-down ratio. The converter is operated at high frequency to obtain low output voltage ripple, reduced magnetics and filters. Zero voltage turn-on is achieved for all switches and zero current turn-on and turn-off is achieved for all diodes in both modes i.e., buck/boost operation. Voltage stress across switches and diode is clamped naturally without external snubber circuit. An experimental prototype has been designed, built and tested in the laboratory to verify the performance of the proposed converter.
GET IEEE BIG DATA,JAVA ,DOTNET,ANDROID ,NS2,MATLAB,EMBEDED AT LOW COST WITH BEST QUALITY PLEASE CONTACT BELOW NUMBER
FOR MORE INFORMATION PLEASE FIND THE BELOW DETAILS:
Nexgen Technology
No :66,4th cross,Venkata nagar,
Near SBI ATM,
Puducherry.
Email Id: praveen@nexgenproject.com
Mobile: 9791938249
Telephone: 0413-2211159
www.nexgenproject.com
GET IEEE BIG DATA,JAVA ,DOTNET,ANDROID ,NS2,MATLAB,EMBEDED AT LOW COST WITH BEST QUALITY PLEASE CONTACT BELOW NUMBER
FOR MORE INFORMATION PLEASE FIND THE BELOW DETAILS:
Nexgen Technology
No :66,4th cross,Venkata nagar,
Near SBI ATM,
Puducherry.
Email Id: praveen@nexgenproject.com
Mobile: 9791938249
Telephone: 0413-2211159
www.nexgenproject.com
Transformerless DC-DC Converter Using Cockcroft-Walton Voltage Multiplier to ...IJERA Editor
In the present scenario the use of transformer for high voltages in converter circuit reduces the overall operating
efficiency due to leakage inductance and use of transformer also increases the operational cost. . Therefore the
proposed system is implemented with transformer less DC-DC converter so as to obtain high DC voltage with
the use of nine stage Cockcroft-Walton (CW) voltage multiplier. The proposed converter operates in CCM
(continuous conduction mode), so that the converter switch stress, the switching losses are reduced. The DC
voltage at the input of the proposed model is low and is boosted up by boost inductor (Ls) in DC-DC converter
stage and performs inverter operation. The number of stages in CW-voltage multiplier circuit is applied with
low input pulsating DC (AC Voltage) voltage where it is getting converted to high DC output voltage. The
proposed converter switches operates at two independent frequencies, modulating (fsm) andalternating (fsc)
frequency. The fsm operates at higher frequency of the output while the fsc operates at lower frequency of the
desired output voltage ripple and the output ripples can be adjusted by the switch Sc1 and Sc2. The regulation of
the output voltage is achieved by controlling the Duty ratio.The simulation is carried over by the MATLABSIMULINK.
IRJET - A Zero Voltage Switching Pulse Width Modulated Multilevel Buck ConverterIRJET Journal
This document presents a new five-level zero voltage switching pulse width modulated multilevel buck converter. The proposed converter uses a multilevel topology to reduce voltage stresses on switches without adding extra voltage. It achieves zero voltage switching for all switches by utilizing active clamping and circulating reactive energy throughout the converter. Simulations in MATLAB were used to verify the performance of the proposed converter. The converter design and operating principles are explained, including modes of operation, component sizing equations, and simulation details.
Lightning Characteristics and Impulse Voltage.Milton Sarker
Lightning characteristics and standard impulse
waveform are related to each other. But the lack
of realization about the relation between them
would make the solution to produce better
protection against lightning surge becomes
harder. Natural lightning surge waveform has
been compared to standard impulse waveform as
evidence that there have similarity between
them. The standard impulse waveform could be
used to test the strength of electrical equipment
against the lightning. Therefore designing and
simulating the impulse generator are the purpose
of this project beside to get better understanding
about lightning characteristics. This project aims
to develop an impulse generator circuit. The
main objectives of this work are two folds: the
first is the characterization of impulse voltages
and the second is the designing of an impulse
voltage generator. Our working purpose is to
give a concept about Impulse voltages and
impulse generator to the students and
researchers.
This document summarizes a research paper that proposes and evaluates a novel interleaved ZCS boost DC-DC converter topology for photovoltaic interfaces. The converter uses two quasi-resonant switch blocks and lossless snubbers to achieve soft switching. Simulation results show the converter achieves reduced voltage and current ripple compared to conventional designs. A dual loop control scheme with an outer voltage loop and inner current loop is used to regulate the output. Coupling inductors between converter cells further improve transient response and reduce ripple. The proposed converter design and control scheme effectively interfaces photovoltaic systems with loads.
Voltage Control of Dual Active Bridge Converter for CO-Amorphous Core Materia...kuldeep12555
Solid-State Transformer (SST) provides versatile power system operation. In the smart world, there are technologies where everything is incorporated that reduce the size and eventually save time in delivering a fast process. It has been seen that solid-state transformer voltage begins to decrease during operation that needs to be regulated through some control strategy. In this paper, a Dual Active Bridge (DAB) converter has been used to control the voltage of SST that employs the Single-Phase Shift (SPS) technique. For further efficiency improvement Co73(Si, B)27 co-amorphous material has been used for the core of SST because co-amorphous alloy has much lower loss compared with Fe-amorphous cores and have limited saturation flux density. Real-time parameters of core have been used in the analysis. It has been evident from the results that DAB dc-dc converter-based SST with SPS control technique is simple and offers better performance compared to stand-alone SST. It improves the overall performance and efficiency of the system. This paper has been accomplished in Matlab® / Simulink environment.
Keywords: Co73 (Si, B)27 Amorphous Core Material; Solid-State transformer (SST); Dual Active Bridge (DAB); High
voltage (HV) Application.
An Asymmetrical Dc-Dc Converter with a High Voltage GainIJMER
An asymmetrical full bridge converter is proposed in the paper. The proposed converter
achieves zero voltage switching of all the power switches. Zero current switching of all the output diodes
are also achieved here. This in turn provides a highly efficienct operation. The proposed converter can
provide a high voltage gain and the voltages across the semi- conductor devices are effectively clamped.
The converter can be utilised effectively in high voltage applications as embedded systems, renewable
energy systems, fuel cells, mobility applications and uninterrupted power supply
This paper proposes a non-isolated soft-switching bidirectional dc/dc converter for interfacing energy storage in DC microgrid. The proposed converter employs a half-bridge boost converter at input port followed by a LCC resonant tank to assist in soft-switching of switches and diodes, and finally a voltage doubler circuit at the output port to enhance the voltage gain by two times. The LCC resonant circuit also adds a suitable voltage gain to the converter. Therefore, overall high voltage gain of the converter is obtained without a transformer or large number of multiplier circuit. For operation in buck mode, the high side voltage is divided by half with capacitive divider to gain higher step-down ratio. The converter is operated at high frequency to obtain low output voltage ripple, reduced magnetics and filters. Zero voltage turn-on is achieved for all switches and zero current turn-on and turn-off is achieved for all diodes in both modes i.e., buck/boost operation. Voltage stress across switches and diode is clamped naturally without external snubber circuit. An experimental prototype has been designed, built and tested in the laboratory to verify the performance of the proposed converter.
GET IEEE BIG DATA,JAVA ,DOTNET,ANDROID ,NS2,MATLAB,EMBEDED AT LOW COST WITH BEST QUALITY PLEASE CONTACT BELOW NUMBER
FOR MORE INFORMATION PLEASE FIND THE BELOW DETAILS:
Nexgen Technology
No :66,4th cross,Venkata nagar,
Near SBI ATM,
Puducherry.
Email Id: praveen@nexgenproject.com
Mobile: 9791938249
Telephone: 0413-2211159
www.nexgenproject.com
GET IEEE BIG DATA,JAVA ,DOTNET,ANDROID ,NS2,MATLAB,EMBEDED AT LOW COST WITH BEST QUALITY PLEASE CONTACT BELOW NUMBER
FOR MORE INFORMATION PLEASE FIND THE BELOW DETAILS:
Nexgen Technology
No :66,4th cross,Venkata nagar,
Near SBI ATM,
Puducherry.
Email Id: praveen@nexgenproject.com
Mobile: 9791938249
Telephone: 0413-2211159
www.nexgenproject.com
Transformerless DC-DC Converter Using Cockcroft-Walton Voltage Multiplier to ...IJERA Editor
In the present scenario the use of transformer for high voltages in converter circuit reduces the overall operating
efficiency due to leakage inductance and use of transformer also increases the operational cost. . Therefore the
proposed system is implemented with transformer less DC-DC converter so as to obtain high DC voltage with
the use of nine stage Cockcroft-Walton (CW) voltage multiplier. The proposed converter operates in CCM
(continuous conduction mode), so that the converter switch stress, the switching losses are reduced. The DC
voltage at the input of the proposed model is low and is boosted up by boost inductor (Ls) in DC-DC converter
stage and performs inverter operation. The number of stages in CW-voltage multiplier circuit is applied with
low input pulsating DC (AC Voltage) voltage where it is getting converted to high DC output voltage. The
proposed converter switches operates at two independent frequencies, modulating (fsm) andalternating (fsc)
frequency. The fsm operates at higher frequency of the output while the fsc operates at lower frequency of the
desired output voltage ripple and the output ripples can be adjusted by the switch Sc1 and Sc2. The regulation of
the output voltage is achieved by controlling the Duty ratio.The simulation is carried over by the MATLABSIMULINK.
IRJET - A Zero Voltage Switching Pulse Width Modulated Multilevel Buck ConverterIRJET Journal
This document presents a new five-level zero voltage switching pulse width modulated multilevel buck converter. The proposed converter uses a multilevel topology to reduce voltage stresses on switches without adding extra voltage. It achieves zero voltage switching for all switches by utilizing active clamping and circulating reactive energy throughout the converter. Simulations in MATLAB were used to verify the performance of the proposed converter. The converter design and operating principles are explained, including modes of operation, component sizing equations, and simulation details.
Lightning Characteristics and Impulse Voltage.Milton Sarker
Lightning characteristics and standard impulse
waveform are related to each other. But the lack
of realization about the relation between them
would make the solution to produce better
protection against lightning surge becomes
harder. Natural lightning surge waveform has
been compared to standard impulse waveform as
evidence that there have similarity between
them. The standard impulse waveform could be
used to test the strength of electrical equipment
against the lightning. Therefore designing and
simulating the impulse generator are the purpose
of this project beside to get better understanding
about lightning characteristics. This project aims
to develop an impulse generator circuit. The
main objectives of this work are two folds: the
first is the characterization of impulse voltages
and the second is the designing of an impulse
voltage generator. Our working purpose is to
give a concept about Impulse voltages and
impulse generator to the students and
researchers.
Quasi-z-source inverter for photovoltaic power generation systemsijiert bestjournal
The Z-Source Inverter (ZSI) has been reported suitable for res idential PV system because of the capability of voltage boost and inversion in a single stage. Recently,four new topol ogies,the quasi-Z-Source Inverters (qZSI),have been derived from the original ZSI. This project ana lyzes one voltage fed topology of these four in detail and applies it to PV power generation systems. By using the new quasi-Z-Source topology,the inverter draws a constant current from the PV array and is capabl e of handling a wide input voltage range. It also features lower component ratings and reduced source stress compared to the traditional ZSI. A prototype which provides three phase 50-Hz,230Vrms ac has been built in laboratory . It is demonstrated from the theoretical analysis and MATLAB/SIMULATION results that t he proposed qZSI can realize voltage buck or boost and dc-ac inversion in a single stage with high reliability and efficiency,which makes it well suited for PV power systems.
Power Factor Corrected Bridgeless Converter Based Improved Power Quality Swit...paperpublications3
Abstract: Many electronic appliances powered up from the utility, utilize the classical method of AC-DC rectification which involves a diode bridge rectifier (DBR) followed by a large electrolytic capacitor. The uncontrolled charging and discharging of this capacitor instigates harmonic rich current being drawn from the utility which goes against the international power quality standard limits. Personal computer (PC) is one of the electronic equipment which is severely affected by power quality problems. Switched Mode Power Supply (SMPS) is an integral part of the computer that converts AC to multiple numbers of suitable DC voltages to impart power to different parts of the PC. It contains a diode bridge rectifier (DBR) with a capacitor filter followed by an isolated DC-DC converter to achieve multiple dc output voltages of different ratings. That result in a highly distorted, high crest factor, periodically dense input current at the single phase ac mains; this violates the limits of international power quality (PQ) standards such as IEC 61000 -3-2 . Employing various power factor corrected (PFC) single-stage and two stage converters effect a perceivable PQ improvement in these SMPSs. Hence from the analysis of different power factor converters a bridgeless buck boost converter is designed and implemented here for near unity power factor.
Keywords: Switched mode power supplies(SMPS), Power Factor correction(PFC) Converter, Power Quality, DC-to-DC Converters, AC-DC rectification.
Title: Power Factor Corrected Bridgeless Converter Based Improved Power Quality Switched Mode Power Supply
Author: Stephy Mathew, Asst. Prof. Nayana J, Asst. Prof. Remya K P
ISSN 2349-7815
International Journal of Recent Research in Electrical and Electronics Engineering (IJRREEE)
Paper Publications
Control and Analysis of VSC Based High Voltage DC Transmissionijsrd.com
High Voltage Direct Current system based on Voltage Source Converters (VSC-HVDC) is becoming a more effective, solution for long distance power transmission especially for off-shore wind plants and supplying power to remote regions Confronting with an increasing demand of power, there is a need to explore the most efficient and reliable bulk power transmission system. Rapid development in the field of power electronics devices especially Insulated Gate Bipolar Transistors (IGBTs) has led to the High Voltage Direct Current (HVDC) transmission based on Voltage Source Converters (VSCs).Since VSCs do not require commutating voltage from the connected ac grid, they are effective in supplying power to isolated and remote loads. Due to its advantages, it is possible that VSC-HVDC will be one of the most important components of power systems in the future. The VSC based HVDC transmission system mainly consists of two converter stations connected by a DC cable. This paper presents the performance analysis of VCS based HVDC transmission system. In this paper a 75kM long VSC HVDC system is simulated for various faults on the ACSide of the receiving station using MATLAB/SIMULINK. The data has been analyzed and a method is proposed to classify the faults by using back propagation algorithm. The simulated results presented in this paper are in good agreement with the published work.
HVDC (high-voltage direct current) is a highly efficient alternative for transmitting large amounts of electricity over long distances and for special purpose applications.
High Efficiency Resonant dc/dc Converter Utilizing a Resistance Compression N...Projectsatbangalore
The document describes a new high-efficiency resonant DC/DC converter topology called the Resistance Compression Network (RCN) converter. It operates with simultaneous zero-voltage switching and near zero-current switching across a wide range of input voltages, output voltages, and power levels, resulting in low switching losses. Experimental results from a 200W prototype show over 95% efficiency is maintained across an input voltage range of 25V to 40V with an output voltage of 400V, and it operates efficiently over a wide output voltage and power range. The RCN converter uses a resistance compression network and on/off control to maintain desired current waveforms and high efficiency over varying operating conditions.
Fuzzy Logic Controller based Bridgeless (BL) Isolated Interleaved Zeta Conver...IJPEDS-IAES
In recent times, high-brightness light emitting diodes (HB-LEDs) are
developing rapidly and it is confirmed to be the future development in
lighting not only because of their high efficiency and high reliability,
however also because of their other exceptional features: chromatic variety,
shock and vibration resistance, etc. In this paper, a bridgeless (BL) Isolated
Interleaved Zeta Converter is proposed for the purpose of reducing the diode
failures or losses; the value of output ripples also gets decreased. The
proposed BL isolated interleaved zeta converter operating in discontinuous
conduction mode (DCM) is used for controlling the brightness of LED
Driver with inherent PFC at ac mains using single voltage sensor. The fuzzy
logic controller (FLC) is used to adjust the Modulation Index of the voltage
controller in order to improve the dynamic response of LED Lamp driver.
Based on the error of converter output voltage, FLC is designed to select the
optimum Modulation Index of the voltage controller. The proposed LED
driver is simulated to achieve a unity power factor at ac mains for a wide
range of voltage control and supply voltage fluctuations.
Hybrid Two Quasi Z-Source Converter for Photovoltaic ApplicationPremier Publishers
This paper presents a Hybrid Two Quasi Z-source (HTQZS) DC-DC converter for photovoltaic applications. These are mainly employed to full fill the demand of the voltage boost in photovoltaic applications from the lower value voltage. The traditional z source networks have some limitations in voltage boosting, so the modified z source means the different combination of the LC components is combined to form the hybrid quasi z source networks. This hybrid two quasi z source dc-dc converters can be applied for the dc-ac, ac-ac, and ac-dc conversions. The structure of the proposed converter is simpler. This converter adds the benefits to the traditional z source converter. This converter draws the continuous input current. The converter simulated is the combination of two different quasi z source networks. This converter uses the duty cycle less than the traditional z source network and gives the more gain than that. PV panel used as source to converter and then the output is inverted and step up.
The DC-fault Blocking Capability by a New Hybrid Multilevel Converter in HVDC...Editor IJCATR
This paper explains the working principles, supported by simulation results, of a new converter topology in-tended for HVDC
application, called the Alternate Arm Con-verter (AAC). Modular Multilevel Converters deliver small footprints and efficiencies above
99% in their half-bridge format, but only deliver DC-fault blocking with full-bridge sub-modules, and with an unacceptable penalty in
efficiency. The Alternate Arm Converter (AAC) is a hybrid circuit topology using a mixture of full-bridge sub-modules and director
switches which is capable of current control through DC faults while maintaining good efficiency in normal operation. It is hybrid
between the modular multi-level converter, because of the presence of H-bridge cells, and the 2-level converter, in the form of director
switches in each arm. This converter is able to generate a multi-level AC voltage and, since its stacks of cells consist of H-bridge cells
instead of half-bridge cells, they are able to generate higher AC voltage than the DC terminal voltage. This allows the AAC to operate
at an optimal point, called the “sweet spot”, where the AC and DC energy flows equal. The director switches in the AAC are responsible
for alternating the conduction period of each arm, leading to a significant reduction in the number of cells in the stacks. Furthermore,
the AAC can keep control of the current in the phase reactor even in case of a DC-side fault and support the AC grid, through a
STATCOM mode. Simulation results and loss calculations are presented in this paper in order to support the claimed features of the
AAC
This document analyzes faults in HVDC transmission systems, specifically DC pole-to-ground faults and AC faults for 2-level and 12-pulse VSC-HVDC systems. It first introduces HVDC and VSC-HVDC technologies. It then simulates and analyzes the behavior of 2-level and 12-pulse VSC-HVDC systems under DC pole-to-ground faults, finding a significant rise in fault current. AC faults including L-G, L-L, and LLL are also simulated and analyzed for 2-level VSC-HVDC. Fault current magnitudes are calculated and verified with simulation results. Finally, it compares the total harmonic distortion of 2-level VSC-HV
1. HVDC transmission systems use direct current for electricity transmission over long distances or through underwater cables. This became practical with the development of thyristors and solid state valves.
2. DC transmission has advantages over AC transmission for long distance transmission, as power transfer in DC lines is unaffected by distance. It also allows asynchronous interconnection between grids and monopolar operation.
3. While DC transmission has higher upfront equipment costs, it has better technical performance than AC transmission for long distance or underwater cables, making it economical beyond the break-even distance.
Multi Pulse Rectifier Using Different Phase Shifting Transformers and its THD...IRJET Journal
This document discusses multi-pulse rectifiers and their use in reducing harmonics compared to a standard six-pulse rectifier. It describes how multi-pulse rectifiers use different transformer configurations like star-delta, delta-star, and zig-zag connections to provide phase shifting and produce more than six pulses of DC voltage per cycle. This reduces the total harmonic distortion in the input current. The document analyzes rectifiers with 6, 12, 18, 24 and 36 pulses and their relative THD levels. Higher pulse rectifiers provide better power quality but require more complex transformer designs.
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.
PV Based Load Resonant for Boost Converter by Using Quasi Z-Source NetworkIJMTST Journal
1. The document describes a novel resonant DC-DC converter that utilizes a quasi Z-source network. It can limit the switching frequency range to achieve high converter efficiency.
2. A cascaded quasi-Z-source inverter is proposed which adds a diode, inductor, and two capacitors to the conventional quasi-Z-source inverter. This reduces the shoot-through duty cycle by over 30% while maintaining voltage gain.
3. Simulation results show that with a 100V input, the output of the voltage doubler circuit with the cascaded quasi-Z-source network can be varied from 300-900V without resonant elements, and from 400-1000V with resonant elements, providing voltage
A HIGH EFFICIENCY CHARGE PUMP FOR LOW VOLTAGE DEVICESVLSICS Design
This document summarizes and analyzes different types of charge pump circuits. It begins by introducing charge pumps and their applications. It then reviews the Dickson charge pump circuit and identifies its limitation of threshold voltage drops across diodes. The document proposes a static CTS charge pump to address this but finds it also has issues from reverse charge sharing. Finally, a dynamic CTS charge pump is presented that uses additional transistors to fully turn on and off switches to prevent reverse charge flow and improve efficiency. Simulation results show its output voltage is higher than other designs.
International Refereed Journal of Engineering and Science (IRJES)irjes
The core of the vision IRJES is to disseminate new knowledge and technology for the benefit of all, ranging from academic research and professional communities to industry professionals in a range of topics in computer science and engineering. It also provides a place for high-caliber researchers, practitioners and PhD students to present ongoing research and development in these areas.
I have created this report for my final semester seminar at Poornima college of engineering Jaipur, electrical department. This report covers various chapters and other contents. feel free to download.
Note: some minor editsin format and a quick spelling check might be needed.
**content source is wikipedia and internet**
any thing you would like to suggest please let me know in the comments.
High Voltage Gain Boost Converter for Micro source Power Conversion systemIDES Editor
The document presents a new high voltage gain boost converter design that uses a coupled inductor and voltage lift technique. Key features of the proposed converter include:
1) It can achieve a high voltage gain while operating at a duty ratio close to 0.65, allowing continuous conduction mode operation.
2) The coupled inductor design recycles energy stored in the leakage inductance, increasing efficiency by clamping voltage on the active switch.
3) A 250W prototype was built with 25V input and 240V output to demonstrate the converter's performance operating at 50kHz.
Steady-state analysis and derivations of voltage gain formulas are provided to explain the operating principles and performance advantages of the proposed
The document summarizes the training report on HVDC transmission systems by Mr. Mohammed Azadar Naqvi at BHEL in Noida. It provides an overview of HVDC transmission, including why it is required due to limitations of AC transmission over long distances. It describes the basic components of an HVDC system including converters, transformers, filters, valves, and switchyards. It also explains the different configurations of HVDC systems such as back-to-back, monopolar, and bipolar arrangements. The report concludes with a list of HVDC projects commissioned in India and references used in the training.
This document summarizes a research paper on a bidirectional DC-DC converter with a Z-source network. The proposed converter aims to increase the output voltage level and regulation range compared to traditional bidirectional converters. It uses a fully bridge symmetrical circuit configuration with voltage and current sources. Simulation results using MATLAB show the converter can reduce current stress and improve efficiency for applications in hybrid electric vehicles and renewable energy systems. Key aspects analyzed include the converter's operating principles, voltage regulation model, and simulation circuit and results demonstrating operation in forward and reverse modes.
High-Power Bidirectional Dual Active Bridge and Double Dual Active Bridge DC-...IRJET Journal
The document summarizes a high-power bidirectional dual active bridge DC-DC converter. It discusses how dual active bridge converters use two full-bridge circuits connected by a transformer and inductor to enable bidirectional power flow and control power transfer between two DC sources by phase shifting square wave voltages generated by each bridge. Zero-voltage switching is enabled through resonance of the inductor and snubber capacitor, improving efficiency. The dual active bridge converter is well-suited for applications requiring high power density and bidirectional power flow such as balancing energy storage systems in aircraft.
El documento contiene varias notas breves de personas mayores que muestran una falta de comprensión de la tecnología moderna, como abreviar el nombre a "DVD", confundir dispositivos como un "CD Rom" con parches de nicotina, y creer incorrectamente que los bebés pueden ser enviados por correo electrónico o bajados de Internet.
La resistencia se refiere a la oposición que encuentra la corriente eléctrica al circular a través de un material. Se mide en ohmios y depende de propiedades del material. Las resistencias se utilizan en circuitos eléctricos y su valor se determina por los colores que presentan.
Quasi-z-source inverter for photovoltaic power generation systemsijiert bestjournal
The Z-Source Inverter (ZSI) has been reported suitable for res idential PV system because of the capability of voltage boost and inversion in a single stage. Recently,four new topol ogies,the quasi-Z-Source Inverters (qZSI),have been derived from the original ZSI. This project ana lyzes one voltage fed topology of these four in detail and applies it to PV power generation systems. By using the new quasi-Z-Source topology,the inverter draws a constant current from the PV array and is capabl e of handling a wide input voltage range. It also features lower component ratings and reduced source stress compared to the traditional ZSI. A prototype which provides three phase 50-Hz,230Vrms ac has been built in laboratory . It is demonstrated from the theoretical analysis and MATLAB/SIMULATION results that t he proposed qZSI can realize voltage buck or boost and dc-ac inversion in a single stage with high reliability and efficiency,which makes it well suited for PV power systems.
Power Factor Corrected Bridgeless Converter Based Improved Power Quality Swit...paperpublications3
Abstract: Many electronic appliances powered up from the utility, utilize the classical method of AC-DC rectification which involves a diode bridge rectifier (DBR) followed by a large electrolytic capacitor. The uncontrolled charging and discharging of this capacitor instigates harmonic rich current being drawn from the utility which goes against the international power quality standard limits. Personal computer (PC) is one of the electronic equipment which is severely affected by power quality problems. Switched Mode Power Supply (SMPS) is an integral part of the computer that converts AC to multiple numbers of suitable DC voltages to impart power to different parts of the PC. It contains a diode bridge rectifier (DBR) with a capacitor filter followed by an isolated DC-DC converter to achieve multiple dc output voltages of different ratings. That result in a highly distorted, high crest factor, periodically dense input current at the single phase ac mains; this violates the limits of international power quality (PQ) standards such as IEC 61000 -3-2 . Employing various power factor corrected (PFC) single-stage and two stage converters effect a perceivable PQ improvement in these SMPSs. Hence from the analysis of different power factor converters a bridgeless buck boost converter is designed and implemented here for near unity power factor.
Keywords: Switched mode power supplies(SMPS), Power Factor correction(PFC) Converter, Power Quality, DC-to-DC Converters, AC-DC rectification.
Title: Power Factor Corrected Bridgeless Converter Based Improved Power Quality Switched Mode Power Supply
Author: Stephy Mathew, Asst. Prof. Nayana J, Asst. Prof. Remya K P
ISSN 2349-7815
International Journal of Recent Research in Electrical and Electronics Engineering (IJRREEE)
Paper Publications
Control and Analysis of VSC Based High Voltage DC Transmissionijsrd.com
High Voltage Direct Current system based on Voltage Source Converters (VSC-HVDC) is becoming a more effective, solution for long distance power transmission especially for off-shore wind plants and supplying power to remote regions Confronting with an increasing demand of power, there is a need to explore the most efficient and reliable bulk power transmission system. Rapid development in the field of power electronics devices especially Insulated Gate Bipolar Transistors (IGBTs) has led to the High Voltage Direct Current (HVDC) transmission based on Voltage Source Converters (VSCs).Since VSCs do not require commutating voltage from the connected ac grid, they are effective in supplying power to isolated and remote loads. Due to its advantages, it is possible that VSC-HVDC will be one of the most important components of power systems in the future. The VSC based HVDC transmission system mainly consists of two converter stations connected by a DC cable. This paper presents the performance analysis of VCS based HVDC transmission system. In this paper a 75kM long VSC HVDC system is simulated for various faults on the ACSide of the receiving station using MATLAB/SIMULINK. The data has been analyzed and a method is proposed to classify the faults by using back propagation algorithm. The simulated results presented in this paper are in good agreement with the published work.
HVDC (high-voltage direct current) is a highly efficient alternative for transmitting large amounts of electricity over long distances and for special purpose applications.
High Efficiency Resonant dc/dc Converter Utilizing a Resistance Compression N...Projectsatbangalore
The document describes a new high-efficiency resonant DC/DC converter topology called the Resistance Compression Network (RCN) converter. It operates with simultaneous zero-voltage switching and near zero-current switching across a wide range of input voltages, output voltages, and power levels, resulting in low switching losses. Experimental results from a 200W prototype show over 95% efficiency is maintained across an input voltage range of 25V to 40V with an output voltage of 400V, and it operates efficiently over a wide output voltage and power range. The RCN converter uses a resistance compression network and on/off control to maintain desired current waveforms and high efficiency over varying operating conditions.
Fuzzy Logic Controller based Bridgeless (BL) Isolated Interleaved Zeta Conver...IJPEDS-IAES
In recent times, high-brightness light emitting diodes (HB-LEDs) are
developing rapidly and it is confirmed to be the future development in
lighting not only because of their high efficiency and high reliability,
however also because of their other exceptional features: chromatic variety,
shock and vibration resistance, etc. In this paper, a bridgeless (BL) Isolated
Interleaved Zeta Converter is proposed for the purpose of reducing the diode
failures or losses; the value of output ripples also gets decreased. The
proposed BL isolated interleaved zeta converter operating in discontinuous
conduction mode (DCM) is used for controlling the brightness of LED
Driver with inherent PFC at ac mains using single voltage sensor. The fuzzy
logic controller (FLC) is used to adjust the Modulation Index of the voltage
controller in order to improve the dynamic response of LED Lamp driver.
Based on the error of converter output voltage, FLC is designed to select the
optimum Modulation Index of the voltage controller. The proposed LED
driver is simulated to achieve a unity power factor at ac mains for a wide
range of voltage control and supply voltage fluctuations.
Hybrid Two Quasi Z-Source Converter for Photovoltaic ApplicationPremier Publishers
This paper presents a Hybrid Two Quasi Z-source (HTQZS) DC-DC converter for photovoltaic applications. These are mainly employed to full fill the demand of the voltage boost in photovoltaic applications from the lower value voltage. The traditional z source networks have some limitations in voltage boosting, so the modified z source means the different combination of the LC components is combined to form the hybrid quasi z source networks. This hybrid two quasi z source dc-dc converters can be applied for the dc-ac, ac-ac, and ac-dc conversions. The structure of the proposed converter is simpler. This converter adds the benefits to the traditional z source converter. This converter draws the continuous input current. The converter simulated is the combination of two different quasi z source networks. This converter uses the duty cycle less than the traditional z source network and gives the more gain than that. PV panel used as source to converter and then the output is inverted and step up.
The DC-fault Blocking Capability by a New Hybrid Multilevel Converter in HVDC...Editor IJCATR
This paper explains the working principles, supported by simulation results, of a new converter topology in-tended for HVDC
application, called the Alternate Arm Con-verter (AAC). Modular Multilevel Converters deliver small footprints and efficiencies above
99% in their half-bridge format, but only deliver DC-fault blocking with full-bridge sub-modules, and with an unacceptable penalty in
efficiency. The Alternate Arm Converter (AAC) is a hybrid circuit topology using a mixture of full-bridge sub-modules and director
switches which is capable of current control through DC faults while maintaining good efficiency in normal operation. It is hybrid
between the modular multi-level converter, because of the presence of H-bridge cells, and the 2-level converter, in the form of director
switches in each arm. This converter is able to generate a multi-level AC voltage and, since its stacks of cells consist of H-bridge cells
instead of half-bridge cells, they are able to generate higher AC voltage than the DC terminal voltage. This allows the AAC to operate
at an optimal point, called the “sweet spot”, where the AC and DC energy flows equal. The director switches in the AAC are responsible
for alternating the conduction period of each arm, leading to a significant reduction in the number of cells in the stacks. Furthermore,
the AAC can keep control of the current in the phase reactor even in case of a DC-side fault and support the AC grid, through a
STATCOM mode. Simulation results and loss calculations are presented in this paper in order to support the claimed features of the
AAC
This document analyzes faults in HVDC transmission systems, specifically DC pole-to-ground faults and AC faults for 2-level and 12-pulse VSC-HVDC systems. It first introduces HVDC and VSC-HVDC technologies. It then simulates and analyzes the behavior of 2-level and 12-pulse VSC-HVDC systems under DC pole-to-ground faults, finding a significant rise in fault current. AC faults including L-G, L-L, and LLL are also simulated and analyzed for 2-level VSC-HVDC. Fault current magnitudes are calculated and verified with simulation results. Finally, it compares the total harmonic distortion of 2-level VSC-HV
1. HVDC transmission systems use direct current for electricity transmission over long distances or through underwater cables. This became practical with the development of thyristors and solid state valves.
2. DC transmission has advantages over AC transmission for long distance transmission, as power transfer in DC lines is unaffected by distance. It also allows asynchronous interconnection between grids and monopolar operation.
3. While DC transmission has higher upfront equipment costs, it has better technical performance than AC transmission for long distance or underwater cables, making it economical beyond the break-even distance.
Multi Pulse Rectifier Using Different Phase Shifting Transformers and its THD...IRJET Journal
This document discusses multi-pulse rectifiers and their use in reducing harmonics compared to a standard six-pulse rectifier. It describes how multi-pulse rectifiers use different transformer configurations like star-delta, delta-star, and zig-zag connections to provide phase shifting and produce more than six pulses of DC voltage per cycle. This reduces the total harmonic distortion in the input current. The document analyzes rectifiers with 6, 12, 18, 24 and 36 pulses and their relative THD levels. Higher pulse rectifiers provide better power quality but require more complex transformer designs.
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.
PV Based Load Resonant for Boost Converter by Using Quasi Z-Source NetworkIJMTST Journal
1. The document describes a novel resonant DC-DC converter that utilizes a quasi Z-source network. It can limit the switching frequency range to achieve high converter efficiency.
2. A cascaded quasi-Z-source inverter is proposed which adds a diode, inductor, and two capacitors to the conventional quasi-Z-source inverter. This reduces the shoot-through duty cycle by over 30% while maintaining voltage gain.
3. Simulation results show that with a 100V input, the output of the voltage doubler circuit with the cascaded quasi-Z-source network can be varied from 300-900V without resonant elements, and from 400-1000V with resonant elements, providing voltage
A HIGH EFFICIENCY CHARGE PUMP FOR LOW VOLTAGE DEVICESVLSICS Design
This document summarizes and analyzes different types of charge pump circuits. It begins by introducing charge pumps and their applications. It then reviews the Dickson charge pump circuit and identifies its limitation of threshold voltage drops across diodes. The document proposes a static CTS charge pump to address this but finds it also has issues from reverse charge sharing. Finally, a dynamic CTS charge pump is presented that uses additional transistors to fully turn on and off switches to prevent reverse charge flow and improve efficiency. Simulation results show its output voltage is higher than other designs.
International Refereed Journal of Engineering and Science (IRJES)irjes
The core of the vision IRJES is to disseminate new knowledge and technology for the benefit of all, ranging from academic research and professional communities to industry professionals in a range of topics in computer science and engineering. It also provides a place for high-caliber researchers, practitioners and PhD students to present ongoing research and development in these areas.
I have created this report for my final semester seminar at Poornima college of engineering Jaipur, electrical department. This report covers various chapters and other contents. feel free to download.
Note: some minor editsin format and a quick spelling check might be needed.
**content source is wikipedia and internet**
any thing you would like to suggest please let me know in the comments.
High Voltage Gain Boost Converter for Micro source Power Conversion systemIDES Editor
The document presents a new high voltage gain boost converter design that uses a coupled inductor and voltage lift technique. Key features of the proposed converter include:
1) It can achieve a high voltage gain while operating at a duty ratio close to 0.65, allowing continuous conduction mode operation.
2) The coupled inductor design recycles energy stored in the leakage inductance, increasing efficiency by clamping voltage on the active switch.
3) A 250W prototype was built with 25V input and 240V output to demonstrate the converter's performance operating at 50kHz.
Steady-state analysis and derivations of voltage gain formulas are provided to explain the operating principles and performance advantages of the proposed
The document summarizes the training report on HVDC transmission systems by Mr. Mohammed Azadar Naqvi at BHEL in Noida. It provides an overview of HVDC transmission, including why it is required due to limitations of AC transmission over long distances. It describes the basic components of an HVDC system including converters, transformers, filters, valves, and switchyards. It also explains the different configurations of HVDC systems such as back-to-back, monopolar, and bipolar arrangements. The report concludes with a list of HVDC projects commissioned in India and references used in the training.
This document summarizes a research paper on a bidirectional DC-DC converter with a Z-source network. The proposed converter aims to increase the output voltage level and regulation range compared to traditional bidirectional converters. It uses a fully bridge symmetrical circuit configuration with voltage and current sources. Simulation results using MATLAB show the converter can reduce current stress and improve efficiency for applications in hybrid electric vehicles and renewable energy systems. Key aspects analyzed include the converter's operating principles, voltage regulation model, and simulation circuit and results demonstrating operation in forward and reverse modes.
High-Power Bidirectional Dual Active Bridge and Double Dual Active Bridge DC-...IRJET Journal
The document summarizes a high-power bidirectional dual active bridge DC-DC converter. It discusses how dual active bridge converters use two full-bridge circuits connected by a transformer and inductor to enable bidirectional power flow and control power transfer between two DC sources by phase shifting square wave voltages generated by each bridge. Zero-voltage switching is enabled through resonance of the inductor and snubber capacitor, improving efficiency. The dual active bridge converter is well-suited for applications requiring high power density and bidirectional power flow such as balancing energy storage systems in aircraft.
El documento contiene varias notas breves de personas mayores que muestran una falta de comprensión de la tecnología moderna, como abreviar el nombre a "DVD", confundir dispositivos como un "CD Rom" con parches de nicotina, y creer incorrectamente que los bebés pueden ser enviados por correo electrónico o bajados de Internet.
La resistencia se refiere a la oposición que encuentra la corriente eléctrica al circular a través de un material. Se mide en ohmios y depende de propiedades del material. Las resistencias se utilizan en circuitos eléctricos y su valor se determina por los colores que presentan.
Este documento é um resumo de um livro ou história sobre uma pessoa chamada Nina. Contém perguntas sobre os detalhes da história, incluindo quem foi hospitalizado e por quê, detalhes sobre as personagens Daniel e Vitor, e se Nina aceitou ou não um convite de Vitor.
Este documento parece ser um código ou número de identificação composto por algarismos. Infelizmente não há outras informações fornecidas para permitir um resumo mais significativo.
O poema descreve um menino que faz tudo ao contrário: ele dorme no armário e deita os fatos na cama, faz omelete com cascas de ovos, toma banho na retrete e anda de pernas para o ar. Ele também chora quando está contente, molha-se ao sol e seca na chuva.
O documento descreve aspectos da era Vargas no Brasil, incluindo a Constituição de 1934, a Consolidação das Leis do Trabalho de 1943, e fotos de comícios e eventos públicos durante o governo Vargas, como o Dia do Trabalhador.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive functioning. Exercise causes chemical changes in the brain that may help boost feelings of calmness, happiness and focus.
O documento discute a energia solar, explicando que ela envolve capturar a luz do sol e transformá-la em energia utilizável. Painéis solares convertem a luz do sol diretamente em eletricidade ou calor. A energia solar não polui e é uma boa opção para lugares remotos. Portugal tem grande potencial para energia solar, mas ainda precisa melhorar seu uso dessa fonte renovável.
O documento discute profissões em ascensão nas áreas de tecnologia, meio ambiente, medicina e educação, fornecendo descrições das principais carreiras em cada área e faixas salariais típicas. Ele também oferece dicas para escolher uma carreira, como avaliar habilidades e falar com profissionais das áreas de interesse.
O documento resume a peça teatral "Auto da Barca do Inferno" de Gil Vicente. Nele, o Corregedor é acusado pelo Diabo de usar seu poder judicial para benefício próprio e se deixar corromper, enquanto o Anjo diz que o Corregedor carrega pecados que o levarão ao inferno. Apesar de tentar se defender, o Corregedor é condenado a ir para o inferno por corrupção e confissão pecaminosa parcial.
San Jorge se encuentra con una doncella que iba a ser sacrificada a un dragón que aterrorizaba a la ciudad. A pesar de las advertencias de la doncella, San Jorge decide enfrentarse al dragón y lo mata. Luego convence a los habitantes de la ciudad de convertirse al cristianismo.
O boletim informativo do PET de História da UFCG apresenta:
1) Uma entrevista com o professor Gervácio Batista Aranha sobre sua trajetória acadêmica e opiniões sobre a graduação em História.
2) A disponibilização online de 200 mil documentos do acervo do Museu Imperial pelo projeto DAMI.
3) A realização da Oficina de Leitura sobre o livro de Walter Benjamin e das palestras "Quinta às Quinze" sobre pesquisas de alunos de História.
La Copa Primavera de Fútbol Aficionado tuvo lugar los días 29 de mayo. El Café Bar Alvaro ganó el campeonato, mientras que el Caf. Rest. Hiedra/San Miguel fue subcampeón. Se enumeran los resultados de los partidos finales y la clasificación final de los 8 equipos. La Supercopa de Fútbol 11 tendrá lugar el 4 de junio entre P.A.L./Braco S.L. y Café Bar Alvaro.
A guerra civil inglesa começou devido ao autoritarismo dos reis Jaime I e Carlos I e à cobrança abusiva de impostos, perseguição aos calvinistas e fechamento do parlamento. O parlamento e as forças burguesas derrotaram o rei, extinguindo a monarquia e formando a república puritana sob Oliver Cromwell.
As três frases resumem o documento da seguinte forma:
[1] A Revolução Inglesa ocorreu devido a transformações econômicas e sociais que fortaleceram a burguesia, mas não seu poder político, gerando tensões com a monarquia absoluta.
[2] Sob Carlos I, as tensões aumentaram com a imposição do anglicanismo e aumento de impostos, levando à guerra civil e sua execução.
[3] A Revolução Gloriosa de 1688 estabeleceu um sistema parlamentar que
Web 2.0: Una oportunidad para la visibilidadTica Salud
Andoni Carrión y Carlos Nuñez
Descripción: La enfermería es una profesión sanitaria que se queja amargamente de la poca visibilidad que tiene su labor. Hablaremos de cómo el uso de las TICs y de la web 2.0 puede servir de motor para aumentar nuestra visibilidad y la de lo que hacemos a diario.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
This document summarizes a seminar presentation on solid state transformers (SSTs) and their implementations. It introduces SSTs as consisting of multi-stage power electronics converters with high frequency transformer isolation. The document outlines some disadvantages of conventional transformers and classifications of SST topologies, including single-stage, dual-active bridge, and multi-stage varieties. Applications discussed include renewable energy integration, electric vehicles, and microgrids. Advantages of SSTs are noted as smaller size, power quality control, fault isolation, and environmental benefits.
Universal demand for power increases due to continuous development to fulfil all these demand. Resources
are used with optimization. A high efficiency and high power factor converters are the major parts of energy
transfer system. This paper present a general review on single stage forward and flyback converter topologies to get
better its performance. This is paper presents a kind general idea of increasing efficiency and power factor of single
stage forward and fly back converter.
The document describes a novel high-gain, high-power DC-DC converter topology for photovoltaic applications. The proposed converter consists of three interleaved boost converters with coupled inductors as the input inductors, along with two voltage multiplier cells. It is able to achieve a voltage gain of 10 and deliver 3kW of output power at 88% efficiency. The operating principle involves eight stages where the switches and diodes operate to transfer energy between the inductors and capacitors, providing high voltage gain while reducing voltage stress on the components. Simulation results validate the design concept and its advantages over existing solutions.
This paper presents the simulation design of dc/dc interleaved boost converter with zero-voltage switching (ZVS). By employin the interleaved structure, the input current stresses to switching devices were reduced and this signified to a switching conduction loss reduction. All the parameters had been calculated theoretically. The proposed converter circuit was simulated by using MATLAB/Simulink and PSpice software programmes. The converter circuit model, with specifications of output power of 200 W, input voltage range from 10~60 V, and operates at 100 kHz switching frequency was simulated to validate the designed parameters. The results showed that the main switches of the model converter circuit achieved ZVS conditions during the interleaving operation. Consequently, the switching losses in the main switching devices were reduced. Thus, the proposed converter circuit model offers advantages of input current stress and switching loss reductions. Hence, based on the designed parameters and results, the converter model can be extended for hardware implementation.
Analysis and Design of Solar Photo voltaic Grid Connected Inverterijeei-iaes
This paper presents an analysis of a single-phase grid-connected photovoltaic inverter. It proposes a new transformerless inverter topology that utilizes two split ac-coupled inductors to operate separately for positive and negative half grid cycles, eliminating shoot-through issues. The topology is designed and analyzed using MATLAB/Simulink. Two modulation techniques, phase disposition PWM and sine PWM, are implemented and compared. Phase disposition PWM is shown to reduce the total harmonic distortion and common mode leakage current compared to sine PWM.
Design of Half Bridge LLC Resonant Converter for Low Voltage Dc ApplicationsIOSRJEEE
An advanced hybrid LLC series resonant converter with united flying-capacitor cell is proposed in this paper to permit the high step-down conversion in the high input voltage applications. The in-built flyingcapacitor branch in the primary side can efficiently share out the primary switch voltage stress related with the half-bridge LLC converters. And the input voltage can be shared correspondingly and automatically between the two series half-bridge components lacking additional balance circuit or control strategies owing to the built-in flying- capacitor cell. Likewise, the inherent soft switching performance in extensive load range that exists in the LLC converters is still kept to decrease the switching losses, which ensures the high efficiency. In addition, the proposed converter can be comprehensive to reduce the switch voltage stress byemploying stacked connection. Finally, a 500∼640 Vinput 48 Voutput 1 kW prototype is built and tested to verify the efficiency of the proposed converter. The results prove that the proposed converter is an excellent candidate for the high input voltage and high step-down dc/dc conversion systems.
A ZVS Interleaved Boost AC/DC Converter Using Super Capacitor Power for Hybri...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.
Fuzzy based control of Transformer less Coupled inductor based DC-DC converterIJERA Editor
Most of the industrial applications use any one of the basic DC-DC converter configurations namely buck,
boost, buck–boost, and Cuk converters. These converters are non-isolating converters. Buck-boost converters
use inductors for storing energy from the source and release the same to load or output. This results in high
stress across magnetic components. This drawback restricts usage of buck-boost converters to low power
applications. Flyback converters popularly have known as buck-boost converters uses transformers for
achieving wide range of step down and step up voltages. Coupled inductor based converters or tapped inductor
based converters are used for achieving wide input – wide output conversion ratios. Coherent transition between
step-down and step-up modes is achieved by a proper control scheme. This paper proposes fuzzy logic based
closed loop control scheme for control of converter switches. Theoretical derivations of control parameters with
their membership values, mamdani based rules for development of fuzzy rules and simulation results of a
coupled inductor based DC-DC converter using MATLAB / SIMULINK are concluded.
PV Cell Fed High Step-up DC-DC Converter for PMSM Drive ApplicationsIJMTST Journal
In this concept novel high step-up dc–dc converter with an active coupled-inductor network is presented for
a sustainable energy system. The proposed converter contains two coupled inductors which can be
integrated into one magnetic core and two switches. The primary sides of coupled inductors are charged in
parallel by the input source, and both the coupled inductors are discharged in series with the input source to
achieve the high step-up voltage gain with appropriate duty ratio, respectively. In addition, the passive
lossless clamped circuit not only recycles leakage energies of the coupled inductor to improve efficiency but
also alleviates large voltage spike to limit the voltage stresses of the main switches. The reverse-recovery
problem of the output diode is also alleviated by the leakage inductor and the lower part count is needed;
therefore, the power conversion efficiency can be further upgraded. The voltage conversion ratios, the effect of
the leakage inductance and the parasitic parameters on the voltage gain are discussed. The voltage stress
and current stress on the power devices are illustrated and the comparisons between the proposed converter
and other converters are given. The simulation results are presented by using Mat lab/Simulink software.
A Novel Three Phase Multi-string Multilevel Inverter with High DC-DC Closed o...rnvsubbarao koppineni
This document proposes and analyzes a novel three-phase multi-string multilevel inverter for photovoltaic systems. The inverter uses a high step-up DC-DC converter to boost and stabilize the output DC voltage from multiple renewable energy sources. It then uses a simplified multilevel inverter topology with only six switches instead of the eight switches used in conventional cascaded H-bridge multilevel inverters, reducing losses. Simulation and experimental results show the inverter provides improved output waveforms, lower harmonics, reduced size and cost compared to other topologies.
IRJET- A DC-DC Converter with High Voltage Gain for Motor Applications us...IRJET Journal
This document describes a proposed DC-DC boost converter with high voltage gain for use in motor applications powered by a fuel cell. The converter aims to step up the low voltage output of the fuel cell to the higher voltage required by the motor drive. It uses a switched capacitor circuit and voltage multiplier configuration to achieve high voltage gain while maintaining a common ground and reducing voltage stress on the power switches. Simulation and experimental results show the converter can achieve a voltage gain sufficient for motor applications with high efficiency and a wide input voltage range. The proposed converter provides advantages over existing designs for fuel cell powered motors.
IRJET- A DC-DC Converter with High Voltage Gain for Motor Applications using ...IRJET Journal
This document describes a proposed DC-DC boost converter with high voltage gain for use in motor applications powered by fuel cells. The converter aims to step up the low output voltage of the fuel cell to the higher voltage required by the motor drive system. It uses two inductors, five capacitors, and two switches operating simultaneously to achieve a high voltage gain without extreme duty cycles. The converter is intended to address issues with existing converters, such as high voltage stress on components, lack of a common ground, and inability to power motor loads. It is analyzed theoretically and through simulation to validate its performance.
High Efficiency Dc-Dc Converter for Renewable Energy Applications and High Vo...IOSRJEEE
Renewable sources like solar PV cell is prefer to be operated at low voltages. This paper proposes a novel high voltage gain, high efficiency dc-dc converter based on coupled inductor, intermediate capacitor. The input energy acquired from the source is first stored in the coupled inductor and intermediate capacitor in a lossless manner. Improve the voltage gain and efficiency of the system. Exorbitant duty cycle values are not required for high voltage gain, when prevent the problems such as diode reverse recovery. Presence of a passive clamp network causes reduced voltage stress on the switch. Overall performance of the renewable energy with a step-up DC/DC converter using closed loop control action is used in the proposed system, improving the overall efficiency of the system.
Solar Based Stand Alone High Performance Interleaved Boost Converter with Zvs...IOSR Journals
This document summarizes a research paper on a solar-based interleaved boost converter with zero-voltage switching and zero-current switching. The converter uses two boost converters connected in parallel with a phase shift to reduce ripple and improve efficiency. Soft-switching techniques are used to reduce switching losses. Simulation results show the converter maintains a constant output voltage while the induction motor output varies with time, and PWM signals control the switches. The converter achieves a power factor of 0.93 and performs efficiently for power conversion from solar panels.
A DC-DC Converter with Ripple Current Cancellation Based On Duty Cycle SelectionIJMER
In this paper a boost dc-dc converter is proposed based on the concept of ripple current cancellation. This proposed system has the novel capability of cancelling the input current ripple at an arbitrarily preselected duty cycle. This is accomplished without increasing the count of the number of components in contrast to other solutions available in the conventional system. In addition to this, the converter also features a high voltage gain without utilizing extreme values of duty cycle or boosting transformers. These features make the converter ideal to process electric power coming from low-voltage power-generating sources, such as renewables. This system also provides details on the principle of operation via topological considerations and a mathematical model. The key factor of reactive component sizing is also discussed in detail. The proposed boost dc-dc converter is evaluated by simulating in MATLAB/Simulink software.
Switched Inductor based Quadratic Following Boost ConverterIRJET Journal
This document describes a switched inductor based quadratic following boost converter for applications requiring high voltage gain such as renewable energy. The converter consists of two switches, five diodes, three inductors, and three capacitors. It operates in two modes: 1) the input voltage charges the inductors while capacitors discharge and 2) the capacitors charge while inductors discharge to charge the output capacitor and supply the load. Simulation results show the converter boosting an input of 42V to an output of 251.8V at 90% efficiency for resistive loads and 80% efficiency for resistive-inductive loads. Analysis indicates this converter provides higher voltage gain than a conventional quadratic boost converter at the same duty cycle with lower output
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.
The document discusses design and implementation of a soft switched high gain current fed full bridge DC-DC converter for fuel cell applications. It provides background on fuel cells and the need for a power electronics interface to convert unregulated electric power from alternative energy sources into usable power. The challenges include designing an efficient and low cost power converter with high efficiency during load operation, large step-up ratio, and low input ripple current. Various converter topologies are reviewed from literature including boost, interleaved boost, coupled inductor, flyback, and half/full-bridge converters. The proposed converter design and steady state analysis is presented along with theoretical waveforms and discussion of hardware implementation.
A Novel Integrated AC-DC Five Level Converter Strategy for Power Factor Corre...IJMTST Journal
Multilevel configuration has the advantage of its simplicity and modularity over the configurations of the other converters. With the application of multilevel converter in the high voltage and large power occasions in recent years, its modulation strategy has become a research hot point in the field of power electronics. The proposed power-factor-correction circuit can achieve unity power factor and ripple-free input current using a coupled inductor. The proposed rectifier can also produce input currents that do not have dead band regions and an output current that is continuous for all load conditions. The features of this converter are that it has lower input section peak current stresses and a better harmonic content than similar converter with a non-interleaved output, the output current is continuous for all load ranges, and the dc bus voltage is less than 450 for all line and load conditions. In this paper, the operation of the new converter is explained, its steady-state characteristics are determined by analysis, and these characteristics are used to develop a procedure for the design of the converter. Hence the simulation results are obtained using MATLAB/SIMULINK software. The proposed system provides a closed loop control for variable output voltage. The SSPFC AC/DC converter can operate with lower peak voltage stresses across the switches and the DC bus capacitors as it is a three-level converter. The proposed concept can be implemented with 5-level for efficient output voltage.
Abnormalities of hormones and inflammatory cytokines in women affected with p...Alexander Decker
Women with polycystic ovary syndrome (PCOS) have elevated levels of hormones like luteinizing hormone and testosterone, as well as higher levels of insulin and insulin resistance compared to healthy women. They also have increased levels of inflammatory markers like C-reactive protein, interleukin-6, and leptin. This study found these abnormalities in the hormones and inflammatory cytokines of women with PCOS ages 23-40, indicating that hormone imbalances associated with insulin resistance and elevated inflammatory markers may worsen infertility in women with PCOS.
A usability evaluation framework for b2 c e commerce websitesAlexander Decker
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1. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 6, 2011
Three-Phase Isolated Boost DC-DC Converter for High
Voltage Applications
R.Samuel Rajesh Babu (Corresponding author)
Research scholar, EEE Department
Sathyabama University, Chennai, India.
E-mail: Samuel.rajeshbabu@gmail.com
Joseph Henry
Professor, EEE Department,
Vel Tech University, Chennai, India.
E-mail: joseph_henry@rediffmail.com
Abstract
The voltage fed DC-DC converter has been suffering from problems associated with large transformer
leakage inductance due to high transformer turn ratio when it is applied to low-voltage, high-current step-
up application such as fuel cells. This paper proposes a new three-phase voltage fed DC-DC converter,
which is suitable for high-voltage, high-current applications. The transformer turn ratio is reduced to half
owing to Δ-Y connection. The zero-voltage and zero-current switches (ZVZCS) for all switches are
achieved over wide load range without affecting effective duty cycle. A clamp circuit not only clamps the
surge voltage but also reduces the circulation current flowing in the high-current side, resulting in
significantly reduced conduction losses. The duty cycle loss can also be compensated by operation of the
clamp switch.The detailed design and operating principles are described and simulated using Pspice. The
proposed converter is very attractive for electrolyser application.
Keywords: High power DC–DC converter, three-phase DC-DC converter, active clamp circuit, Isolation transformer
1. Introduction
High-frequency transformers are usually involved in the DC-DC converter for boost as well as galvanic
isolation and safety purpose. The single-phase DC-DC converter based on the push–pull [1] or full-bridge
[2]–[3] topology has been used as an isolated boost DC-DC converter for less than several Kilowatt power
levels. For higher power level, the single-phase converter could suffer from severe current stresses of the
power components.
The DAB can achieve ZVS on both high- and low-side switches and has no inductors involved in the
power circuit. However, the DAB has many active switches and high ripple currents. Also, the VA rating of
the transformer is comparably large, and manufacturing of the high-frequency transformer with large
leakage inductance is a challenging issue.
The three-phase DC-DC converter has been proposed as an alternative for high-power application.
The three-phase DC-DC converter has several advantages over the single phase DC-DC converter such as
easy MOSFETs selection due to reduced current rating, reduction of the input and output filter’s volume
due to increased effective switching frequency by a factor of three compared to single-phase DC-DC
converter, reduction in transformer size due to better transformer[4] utilization. The three-phase isolated
boost DC-DC converter can be classified to dual active bridge (DAB) converters, current fed converters
and voltage-fed converters.
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2. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 6, 2011
The voltage-fed DC-DC converter has also been used in High voltage applications. An important
advantage of the voltage-fed type is lower switch voltage rating since the switch voltage is fixed to input
voltage, and therefore MOSFETs with lower Rds (ON) can be selected. This is critically beneficial in the
fuel cell application where more than 50% of the power loss is lost as a switch conduction loss at the low-
voltage side [5]. Also, the voltage-fed converter does not have a self-start problem unlike he current-fed
converter. However, the voltage-fed converter suffers from a high transformer turns ratio, which causes
large leakage inductance resulting in large duty cycle loss, [6] increased switch current rating, and
increased surge voltage on the rectifier diode.
A clamping or snubber circuit is usually required for the current-fed converter to limit the transient
voltage caused by transformer leakage inductance [7]. The current-fed converter is also lack of self-starting
capability and, therefore, it necessitates an additional start-up circuitry [8]. The three phase current-fed DC-
DC converter proposed for step-up applications [9] has only three active switches, but the active switches
are hard switched and the passive clamping circuit on the high-current side may cause large amount of
losses. The three-phase current-fed DC-DC converter with an active clamping circuit [10] not only clamps
the surge voltage but also offers ZVS on the active switches. However, this scheme suffers from the high
ripple current imposed on the clamp capacitor located at the high-current side.
The three-phase voltage-fed DC-DC converter, so-called V6 converter, proposed for step-up applications,
[11] significantly mitigates the problem associated with high transformer turn ratio of the voltage-fed type
by utilizing the open Δ-Y type transformer connection, which reduces the required turn ratio to half. Also,
the size of the input filter capacitor to reduce the input current ripple is reduced, since the effective
switching frequency is increased by three times due to the interleaved operation.
Fig. 1. Proposed three-phase Boost DC–DC converter.
In this paper, the turn ratio of the high-frequency transformer is reduced to half by employing the Δ-Y
connection. A clamp circuit that is located at low-current, high-voltage side not only clamps the surge
voltage but significantly reduces the circulating current flowing through high-current side, resulting in
reduced switch conduction losses and transformer copper losses. A three-phase voltage-fed DC-DC
converter for isolated boost application such as Electrolyser is proposed. Further, with the help of the
clamp circuit zero-voltage and zero-current switching (ZVZCS) for all switches over wide load range is
achieved. The duty cycle loss can also be compensated by the clamp switch. The operating principles and
features of the proposed converter are illustrated and the simulation results validate the proposed concept.
Applications
Three-Phase Isolated Boost DC-DC converter will be widely used in various High voltage applications
such as
40
3. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 6, 2011
1. Energy storage system with galvanic isolation
2. Traction drive of hybrid fuel cell system
3. Residential fuel cell generation
4. DC UPS and industrial applications
5. Aerospace power systems
6. Electric vehicles and battery chargers
7. Electrolyser system
8. High step-up applications
2. Operating Principles
As shown in Fig. 1, the proposed three-phase voltage-fed DC-DC converter includes six MOSFET
switches First, the Δ-Y transformer requires the smallest turn ratio for step-up application, and in fact the
required turn ratio is half that of Y-Y or Δ-Δ transformers .The reduction of turn ratio significantly
mitigates problems associated with large leakage inductance, which are large duty cycle loss, increased
switch current rating, and surge voltage on the rectifier diode. This is a big advantage of the three-phase
DC-DC converter over the single-phase dc-dc converter based on the push-pull or full bridge type and
makes the voltage-fed DC-DC converter viable for high gain step-up application. Second, the Δ-Y
configuration is also shown to have the smallest transformer kVA rating and switch current rating [11]. Six
MOSFET switches and a clamp circuit consisting of a MOSFET switch and a capacitor at at low-voltage
side and a three-phase diode bridge, an LC filter at high-voltage side.
State 1 [t1 − t2 ]: S1, S2 , and S6 are conducting, and lower switches S2 and S6 are carrying half of upper
switch S1 current since two transformer primary currents become equal due to the current flow at the
secondary. Since voltage across transformer leakage inductor Vlk1 is a small negative value, which is a
difference between the input voltage and half of the clamp capacitor voltage referred to the primary,
transformer primary current Ip1 is slowly decreasing. The transformer secondary winding current is also
decreasing but larger than load current Io during this mode. Therefore, clamp capacitor Cc is being charged
through the body diode of Sc by the decreasing current.
State 2 [t2 − t3]: When clamp current ISc decreases to zero, the clamp branch is completely disconnected
from the circuit. The input power is still being delivered to the output. Diodes D1 and D2 carry load current
Io through the transformer secondary windings. The voltages across the leakage inductors Vlk1 is zero.
State 3 [t3 − t4]: S1 is turned off at t3 . External capacitor Cext across S1 is charged and parasitic capacitor
Coss of S4 is discharged by reflected load current to the primary 2nIo . Switch voltage VS1 increases
linearly with a slope of 2nIo/(Cext + 2Coss). The upper switch is almost turned off with ZVS if external
capacitor Cext is chosen large enough to hold the switch voltage at near zero at the switching instant. At the
end of this mode, the body diode of S4 is turned on.
State 4 [t4 − t5]: Lower switch S4 is turned on with ZVS since VS4 became already zero at State 3. Turning on
of the clamp switch at t4 causes the rectifier voltage referred to the primary to be applied to the leakage
inductor resulting in rapid decrease of the transformer primary current to zero, and this causes the clamp
capacitor to discharge to supply the load. This reset operation eliminates the circulating current through the
41
4. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 6, 2011
transformer and switches, resulting in significantly reduced conduction losses. Note that the clamp is turned
on with ZVS.
State 5 [t5 − t6 ]: At t5 , the main switch current, transformer winding current, and diode current become
zero, and the clamp capacitor fully supplies the load.
State 6 [t6 − t7 ]: Clamp switch Sc is turned off at t6 , and the load current freewheels through all the diodes.
The clamp switch can also be turned off with ZVS if capacitance across the clamp switch is properly
chosen. The gate signal for lower switch S6 is removed during this mode, and S6 is turned off with ZCS.
State 7 [t7 − t8 ]: Upper switch S3 is turned on at t7 and S2, S3 , and S4 start conducting. Note that S3 is turned
on with ZCS since S3 current linearly increases with a slope of Vin/Lk1. This causes commutation of diode
currents, that is, increase of diode currents ID3 and ID4 and decrease of other diode currents. At the end of
the commutation, the rectifier voltage is clamped by Vc through the body diode of Sc . This is the end of
one-third of the cycle. The second part of the cycle is repeated in the same fashion.
Δ-Y
Fig. 2. Component rating according to transformer Connections (Δ-Y)
Y-Δ
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5. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 6, 2011
Fig. 3. Component rating according to transformer Connections (Y-Δ)
Fig. 4. Six-step switching sequence in 3-phase Inverters
MODE I OPERATION
43
6. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 6, 2011
Q1, Q5, Q6 conduct
R 3R
Req R
2 2
V 2V
i1 s s
Req 3R
i1 R Vs
van vcn
2 3
2Vs
vbn i1 R
3
MODE II OPERATION
Q1, Q2, Q6 conduct
MODE III OPERATION
Q1, Q2, Q3 conduct
In order to achieve ZCS turn-OFF of a lower switch, the primary circulating current should completely be
reset before the upper switch turns on. Therefore, the required dead time for upper switches is determined
by
tdead, U ≥ Lk 4n2Io / Vc
44
7. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 6, 2011
ZCS turn-OFF range of the ZVZCS full-bridge converter is actually restricted by the maximum duty cycle
since the required dead time of lagging leg switches is considerable in this low voltage, High-current
application.
4. Simulation Results
Three-Phase Isolated Boost DC-DC Converter is simulated using Pspice and simulation results are
presented.
L1 D1
1 2
.1m
M1 M3 M5
M7
V1 = 0 V1 V1 = 0 V3 V1 = 0 V5
V1 = 0 V8 V2 = 5 V2 = 5 V2 = 5
V2 = 10 TD = 0 TD = 6.6us TD = 13.2u
TD = 0 TR = 1ns TR = 1ns TR = 1ns
TR = 1ns TF = 1ns TF = 1ns TF = 1ns
TF = 1ns PW = 6.6Us PW = 6.6u PW = 6.6u
V7 PW = 2u PER = 20U PER = 20u PER = 20u
30 PER = 4u
C1
.1u
M4 M6 M2
MUR170
V1 = 0 V4 V1 = 5 V6 V1 = 0 V2
V2 = 5 V2 = 0 V2 = 5
TD = 9.9u TD = 3.3u TD = 3.3u
TR = 1ns TR = 1ns TR = 1ns
TF = 1ns TF = 1ns TF = 1ns
PW = 6.6u PW = 13.2u PW = 6.6u
PER = 20u PER = 20u PER = 20u
0
R8 TX1 R11
1k 1k
D12 D10 D11
TN33_20_11_2P90 MUR160 MUR160 MUR160
R9 R12 V+
TX2
1k 1k
R4
100k
C3
.001u
R10 TN33_20_11_2P90
R13
TX3
D13 D8 D9
1k 1k
MUR160 MUR160 MUR160 V-
0
TN33_20_11_2P90
Fig 5.Simulated circuit diagram
Fig 6.Gate pulse
45
8. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 6, 2011
Fig 7.Three phase output waveform of inverter
Fig 8.Phase to Phase output waveform of inverter
Fig 9.Input and output waveforms for proposed converter
CONCLUSION
In this paper, a new three-phase voltage-fed DC-DC converter for a high-voltage, step-up
application has been proposed. The proposed converter has the following advantages:
1. The duty cycle loss is compensated by the clamp switch. These advantages make the proposed converter
attractive for high-voltage, high-current step up application such as Electrolyser application,fuel cell power
conditioning systems.
46
9. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 6, 2011
2. The required transformer turn ratio is as low as that of the current-fed converter due to the Δ-Y
connection.
3. Circulating current through high-current side is removed due to the reset operation, resulting in
significantly reduced conduction losses.
The proposed converter has advantages like fast current switching, low parasitic circuit inductance, very
high efficiency ,reduced Switching losses, reduced switching stresses, reduced EMI increased power
density and high efficiency. The proposed converter is very attractive for High voltage applications.
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