130,796 research outputs found
Optimization Parameter Design of SEPIC-Cuk Converter
This paper discusses the optimization parameters design of combined SEPIC-Cuk converter based on SEPIC and Cuk operation for dual output voltage polarities. The SEPIC-Cuk converter is designed to be operated in continuous conduction mode, the selection of passive components, i.e., inductor and capacitor are based on the switching frequency, the duty cycle and inductor current ripple. The range of duty cycle for buck operation is 0<D<0.5, meanwhile for boost operation, the duty cycle range is 0.5<D<1.The simulation and experimental results show a good agreement. Thus, the designed parameters of the converter are confirmed. The finding shows that during buck operation, the output voltages are +3.96 V and -3.96 V with duty cycle of 0.25 when the output voltage is 12 V. Meanwhile, during boost operation, the output voltages are +36 V and -36 V with the duty cycle of 0.75 when the output voltage is 12 V
Optimization parameter design of SEPIC-cuk converter
This paper discusses the optimization parameters design of combined SEPIC-Cuk converter based on SEPIC and Cuk operation for dual output voltage polarities. The SEPIC-Cuk converter is designed to be operated in continuous conduction mode, the selection of passive components, i.e., inductor and capacitor are based on the switching frequency, the duty cycle and inductor current ripple. The range of duty cycle for buck operation is 0<D<0.5, meanwhile for boost operation, the duty cycle range is 0.5<D<1.The simulation and experimental results show a good agreement. Thus, the designed parameters of the converter are confirmed. The finding shows that during buck operation, the output voltages are +3.96 V and -3.96 V with duty cycle of 0.25 when the output voltage is 12 V. Meanwhile, during boost operation, the output voltages are +36 V and -36 V with the duty cycleof0.75 when the output voltage is 12
Two-Switch High Gain Non-Isolated Cuk Converter
This paper introduces a two-switch high gain non-isolated Cuk converter which can be used as a high gain DC-DC converter in renewable energy, such as photovoltaic and fuel cell, applications because their output is low. As the conventional, the proposed Cuk converter provides negative output voltage but with a higher voltage in magnitude. The main advantage of the proposed converter is having lower voltage stress with the ability to maintain a higher voltage gain. By combining a switched-inductor and a switched-capacitor into the conventional Cuk converter, the proposed Cuk converter has the ability to reach 13 times the input voltage for a duty cycle D of 0.75. Also, by attaching more switched-inductors to the proposed Cuk converter, more voltage gain can be achieved. A complete theoretical analysis of the Continuous Conduction Mode (CCM) of the proposed Cuk converter is presented and the key aspects of the circuit design have been derived. Also, a comparison in terms of voltage gain and voltage stress between the proposed Cuk converter and Cuk converters using other techniques is presented. The proposed Cuk converter has been designed for 100W rated power, -152V output voltage, 50kHz switching frequency, and 75% duty cycle. The presented converter is simulated in Matlab/Simulink and the results are discussed
A Novel Power Factor Correction Modified Bridge Less-CUK Converter for LED Lamp Applications
In recent decades, several research works have been focused on the efficient Power Factor Correction (PFC) converter design in to meet the power supply efficiency. Conventional PFC cuk converter widely uses the full bridge rectifier which had resulted in overall increase of converter losses and inefficiency. This paper is intended to develop a novel PFC Bridgeless cuk converter for LED lamp applications. In this work, the limitations of the conventional PFC Cuk converter are resolved. The major contributions of the proposed work include the minimization in the number of conduction devices and minimization of the power utility devices which in turn resulted in minimal losses and better efficiency. Moreover, the proposed converter works in DCM which requires only one voltage sensor which results in reduced cost. The proposed Modified BL Cuk converter (MBL-CUK) for LED lamp is simulated in MATLAB and the corresponding results show the better power quality indices such as power factor and Total Harmonic Distortion
Design and Analysis of a Non-Isolated High Gain Step-Up Cuk Converter
Renewable energy sources, such as solar energy, are desired for both economic and ecological issues. These renewable energy sources are plentiful in nature and have a terrific capability for power generation. The only drawback of solar energy, which is one of the best forms of energy sources, is that the output has a low voltage and needs to be stepped up in order to be inserted into the DC grid or an inverter for AC applications. To overcome this drawback, a high gain DC-DC power converter is required in this kind of system. These power converters are needed for a better regulation capability with a small density volume, lightweight, high efficiency, and low cost.
In this dissertation, different topologies of a non-isolated high gain step-up Cuk converter based on switched-inductor (SL) and switched-capacitor (SC) techniques for renewable energy applications, such as photovoltaic and fuel cell, are proposed. These kinds of Cuk converters provide a negative-to-positive step-up DC-DC voltage conversion. The proposed Cuk converters increase the voltage boost ability significantly using the SL and SC techniques compared with the conventional Cuk and boost converters. Then, a maximum power point tracking (MPPT) technique is employed in the proposed Cuk converter to get the maximum power point (MPP) from the PV panel.
The proposed Cuk converters are derived from the conventional Cuk converter by replacing the single inductor at the input, output sides, or both by a SL and the transferring energy capacitor by a SC. The main advantages of the proposed Cuk converters are achieving a high voltage conversion ratio and reducing the voltage stress across the main switch. Therefore, a switch with a lower voltage rating and thus a lower RDS-ON can be used, and that will lead to a higher efficiency. For example, the third topology of the proposed Cuk converter has the ability to boost the input voltage up to 13 times when D=0.75, D is the duty cycle. The voltage gain and the voltage stress across the main switch in all topologies have been compared with conventional converters and other Cuk converters used different techniques. The proposed topologies avoid using a transformer, coupled inductors, or an extreme duty cycle leading to less volume, loss, and cost.
The proposed Cuk converters are analyzed in continuous conduction mode (CCM), and they have been designed for 12V input supply voltage, 50kHz switching frequency, and 75% duty cycle. A detailed theoretical analysis of the CCM is represented, and all the equations have been derived and matched with the results. The proposed Cuk converters have been simulated in MATLAB/Simulink and the results are discussed
Three Topologies of a Non-Isolated High Gain Switched-Inductor Switched-Capacitor Step-Up Cuk Converter for Renewable Energy Applications
This paper introduces three topologies of a non-isolated high gain step-up Cuk converter based on a switched-inductor (SL) and switched-capacitor (SC) techniques for renewable energy applications, such as photovoltaic and fuel cells. These kinds of Cuk converters provide a negative-to-positive step-up dc–dc voltage conversion. The proposed three topologies SLSC Cuk converters increase the voltage boost ability significantly using the switched-inductor and switched-capacitor techniques compared with the classical Cuk and boost converters. The proposed Cuk converters are derived from the classical Cuk converter by replacing the single inductor at the input and output sides with a SL and the transferring energy capacitor by a SC. The main advantages of the proposed SLSC Cuk converters are achieving a high voltage conversion ratio and reducing the voltage stress across the main switch. Therefore, a switch with low voltage rating and thus, of low RDS-ON can be used, and that leads to a higher efficiency. For example, the third topology have the ability to boost the input voltage up to 13 times when D = 0.75, D is the duty cycle. The voltage gain and the voltage stress across the main switch in the three topologies have been compared with the classical Cuk and boost converter. The proposed three topologies avoid using a transformer, coupled inductors, or extreme duty cycles leading to less volume, loss, and cost. The proposed SLSC Cuk converters are analyzed in continuous conduction mode (CCM), and they have been designed for 12 V input supply voltage, 100 W rated power, 50 kHz switching frequency, and 75% duty cycle. A detailed theoretical analysis of the CCM is represented and all the equations have been derived and matched with the results. The proposed three topologies SLSC Cuk converters have been simulated in MATLAB/SIMULINK and results are discussed
Dynamic Characteristics of CUK Converter based on Sliding Mode Control
Abstract: In this study the output voltage is controlled by the Cuk converter using Sliding Mode Control. Here to highlight the advantages of SMC, the PI controller is used in Cuk converter to control the output voltage and it is compared with the SMC. The PI and SMC is implemented in the DC-DC converter and the study is carried in MATLAB SIMULINK. The effect of SMC on the DC-DC converter response in steady state, under line variations, load variations and different component variations will be compared with that of PI controller and results are presented
Modeling and Performance Analysis of New Cuk Converter Topology for Photovoltaic Applications
Photovoltaic (PV) is a technical name in which radiant (photon) energy from the sun is converted to direct current (dc) Electrical Energy. PV power output is still low, continuous efforts are taken to develop the PV converter and controller for maximum power extracting efficiency and reduced cost factor. The maximum power point tracking (MPPT) is a process which tracks one maximum power point from array input, varying the ratio between the voltage and current delivered to get the most power it can. The selection of right converter for different application is a key factor for the optimum performance of the photo voltaic system. This paper details the study on state of the art in research works on Cuk power converters and their characteristics. A new cuk converter topology has also been proposed for the optimal performance of the photovoltaic system. Modeling of the PV array and simulation of basic cuk converter and the proposed cuk converter is carried out in Matlab/Simulink Software. Index Terms - PV Module, MPPT, Incremental Conductance (IC) Algorithm, Cuk converter, Optimal performanc
A bridgeless Cuk PFC converter
A bridgeless Power Factor Correction (PFC) circuit based on Cuk converter is proposed in this paper. The operation during each sub-interval modes of the converter operated in Discontinuous Conduction Mode (DCM) is discussed. The smallsignal and large signal models are presented using Current Injected Equivalent Circuit Approach (CIECA). PLECS/Simulink is used to verify the capability of the proposed converter to regulate the output voltage while the input current regulation is inherent. This converter is capable to operate in universal input voltage condition
MeSH term explosion and author rank improve expert recommendations
Information overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
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