Efficiency Of Boost Converter Research Articles

Neuro-fuzzy-SVPWM switched-inductor-capacitor-based boost inverter for grid-tied fuel cell power generators, design and implementation

Hydrogen energy shows promise as a renewable energy source for various applications like battery and electric vehicle charging stations, as well as grid connections. However, high current ripple from fuel cells (FCs) and inadequate voltages for grid use pose challenges. This study presents a novel solution using neural fuzzy network control in a high-gain DC-DC boost converter to address these issues. The suggested converter charges in parallel and discharges in series, minimizing the current ripple range in the fuel cell network. Additionally, the switch-capacitor cell efficiently increases the output voltage.In this study, a Neuro-fuzzy system with 9 rules is trained meticulously over 50 epochs using hybrid optimization and grid partition methods, achieving a low training error of 0.045 with 522,064 samples. The neural fuzzy network, employing the weighted average method for Defuzzification, produces duty cycle values from 0.02 to 0.5 in response to input signals. Additionally, an innovative Space Vector Pulse Width Modulation (SVPWM) approach within the inverter circuit enhances voltage generation precision and power quality for grid delivery, notably reducing current ripple and ensuring stable power supply. This combined with the neural fuzzy network in the converter efficiently converts hydrogen energy into AC voltage for seamless grid integration, revolutionizing boost converter efficiency and advancing hydrogen energy utilization across various energy sectors.

Ringing loss analysis and its influence on boost converter efficiency

Ringing of voltage and/or current waveforms is inevitable in hard-switching converters, especially when the operational frequency increases. The impact of ringing is increasing due to the development of high-speed switching devices. However, the extra loss introduced by ringing is not considered in the evaluation of the converter's total loss. This paper proposes detailed analysis of the ringing loss and its estimation method. It is shown that the ringing introduces extra loss, which is not included in the conventional method for loss estimation. The loss introduced by ringing is determined by its magnitude and the parasitic inductance in the power loop. In addition to the analysis, experiments are conducted on a boost converter with different ringing to evaluate the influence of ringing on the overall efficiency. It is shown that the ringing has a greater influence on efficiency under low current condition.

An energy harvesting system for time-varying energy transducers with FOCV based dynamic and adaptive MPPT for 30 nW to 4 mW of input power range

This article, for the first time, presents an energy harvesting system (EHS) for harvesting the energy from the continuous time-varying energy harvesters using the fractional open-circuit-voltage (FOCV) based dynamic and adaptive maximum power point tracking (MPPT). The proposed EHS includes an energy harvester, a start-up circuit, a DC-DC boost converter, a DC-DC buck converter, and a control circuit. In the FOCV based MPPT, a fraction of the open-circuit-voltage (OCV) of the energy harvester, is maintained at the output of the energy harvester (input of a DC-DC boost converter). In the proposed work, OCV of the energy harvester is dynamically and adaptively sampled depending on the ambient conditions and the maximum available power from the energy harvester. This helps in improving the tracking efficiency of the proposed MPPT circuit for the time-varying energy harvester by more than 10%. The boost converter switching time period instants are utilized for sampling the OCV of the energy harvester. A 12-stage Dickson based charge pump along with a 5-stage ring oscillator with a modified clock distribution is used for the start-up. Post-layout simulated results of the proposed EHS are presented in the 180 nm mixed-mode CMOS technology. The tracking efficiency and the boost converter efficiency for a wide range of the available input power (30 nW to 4 mW) compatible with many time-varying ambient energy harvesters in both indoor and outdoor places are presented. For a time-varying energy harvester, the tracking efficiency is more than 96%. For a source resistance of 100 kΩ, the boost converter's efficiency is 60.09% and 90.77% at available power of 56 nW and 1.6 μW, respectively.

Application of Modified MPPT Algorithms: A Comparative Study between Different Types of Solar Cells

Due to the broad needs for energy as market demands, searching on how to improve the efficiency of the PV systems is an essential concern for researchers to worry about. So, it is crucial to force the PV system to work at its peak power point in order to get the maximum available power from the photovoltaic panel. This paper presents a comprehensive comparison between four Maximum Power Point Tracking (MPPT) Algorithms; Perturb and Observe (P&O), Incremental Conductance (INC), Modified Variable Step Size Perturb and Observe (M-VSS-P&O) and Modified Variable Step Size Incremental Conductance (M-VSS-INC) by using of the DC-DC boost converter for three different kinds of solar cells. These cells are polycrystalline KC200GT cell, monocrystalline shell SQ85 cell and thin film shell ST40 cell. Simulations have been performed using MATLAB-SIMULINK for the three types of solar cells to investigate their performance under both standard test conditions (STC) and slowly varying and sudden changes in solar irradiance. The study has considered the response time, output power efficiency and steady-state-oscillations. The simulation results of the modified algorithms show an improvement in the cell performance in steady state conditions, tracking time and boost converter efficiency as well as an enhancement in the dynamic response in tracking the maximum power point (MPP) in varying climatic conditions over conventional algorithms.

A maximum power-point tracking multiple-input thermal energy harvesting module

In this paper, a new maximum power-point tracking multiple-input boost converter is presented. The proposed structure monitors the input power and selects an input which would deliver the most power to the load. This is done using an extra phase to estimate and compare the available input power of the inputs. The available input power of a TEG depends on the open-circuit voltage and the internal resistance of the input source. Based on the analytical solutions, a simple circuitry is proposed which can predict which source should be selected in order to deliver the most power to the load. The proposed boost converter utilizes only a single inductor and a single capacitor and four switches. The proposed circuit is simulated using a 0.18-μm CMOS technology. HSpice simulation results show that the system can successfully selects an input which results in greater harvested power. The peak boost converter efficiency is 55% while delivering 7mW to the load.

Thermoelectric generators for wearable body heat harvesting: Material and device concurrent optimization

Body heat harvesting systems based on thermoelectric generators (TEGs) can play a significant role in wearable electronics intended for continuous, long-term health monitoring. However, to date, the harvested power density from the body using TEGs is limited to a few micro-watts per square centimeter, which is not sufficient to turn on many wearables. The thermoelectric materials research has been mainly focused on enhancing the single parameter zT, which is insufficient to meet the requirements for wearable applications. To develop TEGs that work effectively in wearable devices, one has to consider the material, device, and system requirements concurrently. Due to the lack of an efficient heatsink and the skin thermal resistance, a key challenge to achieving this goal is to design systems that maximize the temperature differential across the TEG while not compromising the body comfort. This requires favoring approaches that deliver the largest possible device thermal resistance relative to the external parasitic resistances. Therefore, materials with low thermal conductivity are critically important to maximize the temperature gradient. Also, to achieve a high boost converter efficiency, wearable TEGs need to have the highest possible output voltage, which calls for a high Seebeck coefficient. At the device level, dimensions of the legs (length versus the base area) and fill factor are both critical parameters to ensure that the parasitic thermal resistances are again negligible compared to the resistance of the module itself. In this study, the concurrent impact of material and device parameters on the efficiency of wearable TEGs is considered. Nanocomposite thermoelectric materials based on bismuth telluride alloys were synthesized using microwave processing and optimized to meet the requirements of wearable TEGs. Microwave energy decrystallized the material leading to a strong reduction of the thermal conductivity while maintaining a high zT at the body temperature. A comprehensive quasi-3D analytical model was developed and used to optimize the material and device parameters. The nanocomposite TEG produced 44 μW/cm2 under no air flow condition, and 156.5 μW/cm2 under airflow. In comparison to commercial TEGs tested under similar conditions, the nanocomposite based TEGs exhibited 4–7 times higher power density on the human body depending on the convective cooling conditions.

Analytical solutions for high efficiency maximum power point tracking boost converters

SummaryThis paper presents analytical solutions for high efficiency maximum power point tracking boost converters. Employing analytical approach, it is shown that insertion of a capacitor in parallel with the input voltage source successfully increases the efficiency. Besides, the optimum value for this capacitor is derived. Also, it is proved that the maximum power point of such a boost converter is independent of the input voltage source. In order to evaluate this analytical approach, a typical boost converter is designed in a 180‐nm CMOS technology using Hspice. Based on the simulation results, it is shown that all of the input available power can be stored in the inductor. This proves that, with the aid of the proposed approach, maximum power point tracking can be done by >99% accuracy. Also, the boost converter efficiency is as high as 84% which shows the effectiveness of the proposed approach.

An enhanced P&O checking algorithm MPPT for high tracking efficiency of partially shaded PV module

This paper presents the impact of partial shading to the PV system and proposes an enhanced Perturb and Observe (P&O) algorithm with a checking algorithm. This checking algorithm compared all existed peaks on the PV curve to clarify the global maximum power point (GMPP). The boost converter duty cycle is calculated using voltage at MPP (VMPP), identified through a variable step size P&O algorithm. The major advantages of this method are low-cost, simple and accurate. The PV power and voltage rating used for this paper are 42 W and 17 V respectively. Boost converter is used to boost the PV voltage twice for the load. Two different methodologies have been done which were a simulation model using MATLAB/Simulink and hardware implementation using Arduino Mega 2560. Both simulation and hardware results indicated that the proposed algorithm provided excellent efficiency of 99.96% and 99.86% respectively. The proposed algorithm improved the conventional P&O MPPT tracking efficiency by more than 16% during partial shading condition. On the other hand, the system with conventional P&O MPPT seems unstable and produced higher percentage of error. Plus, the boost converter efficiency also provided more than 70% in both conditions. In summary, the proposed method is useful for solar PV in any irradiation condition with high efficiency of the system.

Novel Switch Adaptive Control to Improve the Efficiency of Boost Converter in Photovoltaic Systems

The efficiency of photovoltaic power generation is affected by the changeable weather conditions. This paper improves the efficiency of a standalone PV system over a wider range of operating conditions by employing novel switch adaptive control to an interleaved boost converter. With various loads, simulation and experimental results show that the interleaved boost converter with novel switch adaptive control offers better performance and higher conversion efficiency under changeable weather conditions.

Multilayer laminated piezoelectric bending actuators: design and manufacturing for optimum power density and efficiency

In previous work we presented design and manufacturing rules for optimizing the energy density of piezoelectric bimorph actuators through the use of laser-induced melting, insulating edge coating, and features for rigid ground attachments to maximize force output, as well as a pre-stacked technique to enable mass customization. Here we adapt these techniques to bending actuators with four active layers, which utilize thinner material layers. This allows the use of lower operating voltages, which is important for overall power usage optimization, as typical small-scale power supplies are low-voltage and the efficiency of boost-converter and drive circuitry increases with decreasing output voltage. We show that this optimization results in a 24%–47% reduction in the weight of the required power supply (depending on the type of drive circuit used). We also present scaling arguments to determine when multi-layer actuator are preferable to thinner actuators, and show that our techniques are capable of scaling down to sub-mg weight actuators.

Analysis and Comparison of a Fast Turn-On Series IGBT Stack and High-Voltage-Rated Commercial IGBTS

High-voltage-rated solid-state switches such as insulated-gate bipolar transistors (IGBTs) are commercially available up to 6.5 kV. Such voltage ratings are attractive for pulsed power and high-voltage switch-mode converter applications. However, as the IGBT voltage ratings increase, the rate of current rise and fall are generally reduced. This tradeoff is difficult to avoid as IGBTs must maintain a low resistance in the epitaxial or drift region layer. For high-voltage-rated IGBTs with thick drift regions to support the reverse voltage, the required high carrier concentrations are injected at turn on and removed at turn off, which slows the switching speed. An option for faster switching is to series multiple, lower voltage-rated IGBTs. An IGBT-stack prototype with six, 1200 V rated IGBTs in series has been experimentally tested. The six-series IGBT stack consists of individual, optically isolated, gate drivers and aluminum cooling plates for forced air cooling which results in a compact package. Each IGBT is overvoltage protected by transient voltage suppressors. The turn-on current rise time of the six-series IGBT stack and a single 6.5 kV rated IGBT has been experimentally measured in a pulsed resistive-load, capacitor discharge circuit. The IGBT stack has also been compared to two IGBT modules in series, each rated at 3.3 kV, in a boost circuit application switching at 9 kHz and producing an output of 5 kV. The six-series IGBT stack results in improved turn-on switching speed, and significantly higher power boost converter efficiency due to a reduced current tail during turn off. The experimental test parameters and the results of the comparison tests are discussed in the following paper