High Step-up Voltage Conversion Ratio Research Articles

Development of a Thermal Energy Harvesting Converter with Multiple Inputs and an Isolated Output

In this paper, an isolated multi-input single-output (MISO) converter is developed and applied to a thermoelectric energy conversion system to harvest thermal energy. The thermoelectric generators have individual maximum power point tracking functions. Furthermore, such a converter has a high step-up voltage conversion ratio. In addition, the presented converter is imposed on the thermoelectric energy conversion system with the three-point weighting strategy adopted to realize the maximum power point tracking (MPPT). In this paper, the basic principles of this converter are first described and analyzed, and finally some simulated and experimental results are offered to verify the feasibility and effectiveness of such a thermal energy harvesting system.

A Three-Switch-Based Single-Input Dual-Output Converter With Simultaneous Boost & Buck Voltage Conversion

With the increasing demand of applications that have two different output voltages, the single-input dual-output (SIDO) converter with fewer components is becoming the cost-effective option instead of employing two single-input single-output converters. However, the cross-regulation of different outputs is still a challenge in SIDO converters design. To save cost and obtain improved cross-regulation performance, a novel SIDO converter consisting of three active switches is proposed in this article. Owing to the use of a voltage multiplier circuit, a high step-up voltage conversion ratio is achieved with relatively low voltage stress of switches. Thanks to the independent power flow and two control variables, the cross-regulation performance is improved, and simultaneous buck as well as boost output voltages is realized. Additionally, all switches can achieve zero-voltage switching operation, which contributes to a significant switching loss reduction. The operation characteristics, design considerations, and control strategy of the proposed converter are analyzed. To verify the theoretical analysis and measure the power efficiency, a prototype circuit with 48 V input and 24 V/2 A, 200 V/1 A outputs is built.

A High-Efficiency DC/DC Converter for High-Voltage-Gain, High-Current Applications

A new class of high-voltage-gain dc–dc converters for high-efficiency and transformer-less dc–dc applications, where large voltage step-up ratios are required, is presented in this paper. The converter is derived from the hybrid integration of a switched-capacitor converter and a boost converter. It features high step-up voltage conversion ratio with a moderate duty cycle, nonpulsating input current, low-voltage stress on all of the switches, easy implementation of control and driving circuits, scalability for high-current high-power applications, and low cost due to reduced components via combination of a two-stage converter into a single-stage converter. Full soft-charging operation and minimal device voltage stresses are achieved under all operating conditions. Steady-state operations of the converter are comprehensively analyzed. A 300-W prototype of a 19-time converter achieving the peak efficiency of 96.1% is built. Both simulation and experimental results validating the theoretical analysis and operation of the converter are provided.

A Novel High Step-up DC-DC Converter for Photovoltaic Applications

This paper proposes a new topology of a high step-up dc-dc converter for photovoltaic system applications. The proposed converter can boost up the low input voltage, about 20 V, generated from the PV array to the high output voltage level of approximately 400 V. The proposed converter employs only one power switch to achieve a high step-up voltage conversion ratio, approximately 20 times, without the extremely large duty cycle. The operating principles and steady-stage analyses of continuous conduction mode are described in detail. The relationship between the step-up voltage ratio and the duty cycle of the proposed converter is analyzed. The simulation and experimental results are shown to demonstrate the effectiveness of the proposed high step-up single-switch dc-dc converter for low-input and high-output voltage systems.

Multicell Switched-Inductor/Switched-Capacitor Combined Active-Network Converters

High step-up voltage gain dc/dc converters are widely used in renewable energy power generation, uninterruptible power system, etc. In order to avoid the influence of leakage inductor in coupled inductors based converters, switched-inductor boost converter (SL-boost), switched-capacitor boost converter (SC-boost) and active-network converter (ANC) have been developed. With the transition in series and parallel connection of the inductors and capacitors, high step-up voltage conversion ratio can be achieved. This paper discusses the characteristics of the switched inductor and switched-capacitor cell; makes some comparisons between the ANC and boost converter. Based on the aforementioned analysis, this paper proposed the multicell switched-inductor/ switched-capacitor combined active network converters (MSL/SC-ANC). The proposed converters combine the advantages of SL/SC unit and active-network structure. Compared with previous high step-up converters, the novel converter provides a higher voltage conversion ratio with a lower voltage/current stress on the power devices, moreover, the structure of proposed SL/SC-ANC is very flexible, which means the quantity of SL and SC cells can be adjusted according to required voltage gain. A 20 times gain prototype is designed as an example to show the design procedure. Theoretical analysis and experimental results are presented to demonstrate the feature of the proposed converter.

High Step-Up DC—DC Converter for AC Photovoltaic Module with MPPT Control

Abstract This paper presents the high gain step-up BOOST converter which is essential to step up the low output voltage from PV panel to the high voltage according to the requirement of the application. In this paper a high gain BOOST converter with coupled inductor technique is proposed with the MPPT control. Without extreme duty ratios and the numerous turns-ratios of a coupled inductor this converter achieves a high step-up voltage-conversion ratio and the leakage energy of the coupled inductor is efficiently recycled to the load. MPPT control used to extract the maximum power from PV panel by controlling the Duty ratio of the converter. The PV panel, BOOST converter and the MPPT are modeled using Sim Power System blocks in MATLAB/SIMULINK environment. The prototype model of the proposed converter has been implemented with the maximum measured efficiency is up to 95.4% and full-load efficiency is 93.1%.

English

Multiphase dc-dc converters are widely used in modern power electronics applications due to their advantages over single-phase converters. Such advantages include reduced current stress in both the switching devices and passive elements, reduced output current ripple, increase in output voltage and overall efficiency and so on. The output current ripple of a converter can be significantly reduced by virtue of the interleaving connection. This paper presents a design and simulation of an interleaved high step up DC-DC converter with PID controller. The control strategy of the converter is based on a Proportional-Integral-Derivative (PID) controller. The proposed converter achieves a high step-up voltage-conversion ratio without extreme duty ratio and the numerous turns-ratios of a coupled inductor and reduction in the input current ripple with the efficiency higher than 97%.The PID controller is used in the feedback to reduce the rise time and steady state error. The proposed interleaved high step up DC-DC converter model along with PID controller is modeled using SIMULINK and the simulation results are presented in this paper to authenticate the proposed scheme.

Soft Computing Module of High Step-Up DC–DC Converter for PV Module using Simulink Environment

Within the photovoltaic (PV) power-generation market, the PV module has shown obvious growth. However, a high voltage gain converter is essential for the module’s grid connection through a dc–ac inverter. This paper proposes a converter that employs a floating active switch to isolate energy from the PV panel when the ac module is OFF; this particular design protects installers and users from electrical hazards. Without extreme duty ratios and the numerous turns-ratios of a coupled inductor, this converter achieves a high step-up voltage-conversion ratio; the leakage inductor energy of the coupled inductor is efficiently recycled to the load. These features explain the module’s high-efficiency performance. The detailed operating principles and steady-state analyses of continuous, discontinuous, and boundary conduction modes are described. A 15V input voltage, 200V output voltage, and 100W output power prototype circuit of the proposed converter has been implemented; its maximum efficiency is up to 95.3% and full-load efficiency is 92.3%. DOI: http://dx.doi.org/10.11591/ijpeds.v3i1.1585

High Efficient Module of Boost Converter in PV Module

Within the photovoltaic (PV) power-generation market, the PV module has shown obvious growth. However, a high voltage gain converter is essential for the module’s grid connection through a dc–ac inverter. This paper proposes a converter that employs a floating active switch to isolate energy from the PV panel when the ac module is OFF; this particular design protects installers and users from electrical hazards. Without extreme duty ratios and the numerous turns-ratios of a coupled inductor, this converter achieves a high step-up voltage-conversion ratio; the leakage inductor energy of the coupled inductor is efficiently recycled to the load. These features explain the module’s high-efficiency performance. The detailed operating principles and steady-state analyses of continuous, discontinuous, and boundary conduction modes are described. A 15V input voltage, 200V output voltage, and 100W output power prototype circuit of the proposed converter has been implemented; its maximum efficiency is up to 95.3% and full-load efficiency is 92.3%. DOI: http://dx.doi.org/10.11591/ijece.v2i6.1586

A Safety Enhanced, High Step-Up DC–DC Converter for AC Photovoltaic Module Application

Within the photovoltaic (PV) power-generation market, the ac PV module has shown obvious growth. However, a high voltage gain converter is essential for the module's grid connection through a dc-ac inverter. This paper proposes a converter that employs a floating active switch to isolate energy from the PV panel when the ac module is off; this particular design protects installers and users from electrical hazards. Without extreme duty ratios and the numerous turns-ratios of a coupled inductor, this converter achieves a high step-up voltage-conversion ratio; the leakage inductor energy of the coupled inductor is efficiently recycled to the load. These features explain the module's high-efficiency performance. The detailed operating principles and steady-state analyses of continuous, discontinuous, and boundary conduction modes are described. A 15 V input voltage, 200 V output voltage, and 100 W output power prototype circuit of the proposed converter has been implemented; its maximum efficiency is up to 95.3% and full-load efficiency is 92.3%.

New zero-voltage switching DC–DC converter for renewable energy conversion systems

This study presents a novel DC–DC converter for renewable energy conversion systems with photovoltaic (PV) solar cell or fuel cell stack input. The proposed converter is based on a boost converter and a voltage-doubler configuration with a coupled inductor to achieve high step-up voltage conversion ratio. An active snubber is adopted to clamp the voltage stress of the active switch and to release the energy stored in leakage and magnetising inductances. Compared to a conventional boost converter, the adopted converter has a wide turn-off period such that a high output voltage can be achieved. Since an asymmetrical pulse-width modulation is adopted to control both active switches, the leakage inductance and output capacitance of the active switch are resonant in the transition interval. Therefore both active switches are turned on at zero-voltage switching to overcome the disadvantages of a conventional boost converter with low circuit efficiency and narrow turn-off period. Finally, experiments conducted on a laboratory prototype rated at 400 W are presented to verify the effectiveness of the adopted converter.

Photovoltaic panel integrated power conditioning system using a high efficiency step-up DC–DC converter

This paper presents a high efficiency photovoltaic (PV) panel integrated power conditioning system (PCS) by proposing a high efficiency step-up DC–DC converter. The suggested PCS consists of a high efficiency DC–DC converter and a single-phase DC–AC inverter. Each PV panel has its own DC–AC converter, performing the maximum power point tracking (MPPT) function and increasing its flexibility and expandability. Moreover, the proposed DC–DC converter converts the low PV panel voltage into a high DC-link voltage with a high step-up voltage conversion ratio. It can reduce the switching power losses, increasing the power conversion efficiency. The performance of the suggested PCS has been verified through a 180 W prototype of the PCS for a 60 Hz/120 V ac power grid. The proposed DC–DC converter achieves a high efficiency of 96.0%. The PCS including the DC–DC converter and DC–AC inverter achieves an efficiency of 93.1% with an almost unity power factor.