Non-inverting Buck-boost DC-DC Converter Research Articles

Dead-Time Evaluation With Switching Frequency for GaN-Based Non-Inverting Buck-Boost DC–DC Converter Using FPGA-Based High-Frequency Control

Dead-Time Evaluation With Switching Frequency for GaN-Based Non-Inverting Buck-Boost DC–DC Converter Using FPGA-Based High-Frequency Control

Robust Discrete-Time Hybrid Controller for Non-Inverting Buck-Boost DC-DC Converter

Petro-Processors of Louisiana, Inc. (PPI) site, located North of the city of Baton Rouge Parish, used two sites as depositories for various petrochemical wastes from mainly the 1960s until the 1980s. The main problem was the potential for leachate migration and for exposure of toxic materials, which had been released into local waterways. Therefore, the site is considered a public health hazard area because of risks to human health from past, present, and future exposure to hazardous substances. This study focuses on investigating selected chlorinated organic liquids, which are the predominant contaminants among all wastes: Hexachlorobenzene (HCB) and Hexachlorobutadiene (HCBD) with possible health effects using a risk assessment study. The results show that even though the petrochemical waste disposal has completely shut down since1980, it will still take an average of the HCB and HCBD to reach the domestic well with groundwater is 68 years and 57 years, respectively via slow migration, which will increase the cancer risks for the people who live near PPI site. Our results indicated that the cancer risks of exposure to HCB and HCBD are 4.6x10-6 and 2.6x10-3, respectively, which are more than the 10-6 goal. In addition, this study can be used at similar sites and for different compounds to investigate the potential impacts of pollutants on human health.

Direct Model Predictive Control of Noninverting Buck-boost DC-DC Converter

In this paper, direct model predictive control (DMPC) of the noninverting buck-boost DC-DC converter with magnetic coupling between input and output is proposed. Unlike most of the other converters, the subject converter has the advantage of exhibiting minimum phase behavior in the boost mode. However, a major issue that arises in the classical control of the converter is the dead zone near the transition of the buck and boost mode. The reason for the dead zone is practically unrealizable duty cycles, which are close to zero or unity, of pulse width modulation (PWM) near the transition region. To overcome this issue, we propose to use DMPC. In DMPC, the switches are manipulated directly by the controller without the need of PWM. Thereby, avoiding the dead zone altogether. DMPC also offers several other advantages over classical techniques that include optimality and explicit current constraints. Simulations of the proposed DMPC technique on the converter show that the dead zone has been successfully avoided. Moreover, simulations show that the DMPC technique results in a significantly improved performance as compared to the classical control techniques in terms of response time, reference tracking, and overshoot.

Mixed-Ripple Adaptive On-Time Controlled Non-Inverting Buck-Boost DC-DC Converter With Adaptive-Window-Based Mode Selector

A mixed-ripple adaptive on-time controlled non-inverting buck-boost dc-dc converter with novel adaptive-window-based mode selector is proposed, and no compensator is required in the control circuits. For achieving high conversion efficiency, the non-inverting buck-boost dc-dc converter only works in the buck or boost modes, not the buck-boost mode. Moreover, with the proposed mode selector, smooth transition between buck mode and boost mode can be achieved. Besides, it makes the efficiency reach its maximum when the input voltage approaches the output voltage. The proposed chip was implemented by using a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.35~\mu \text{m}$ </tex-math></inline-formula> CMOS 2P4M 3.3V/5V mixed-signal polycide process. The input voltage may range from 2.5 to 5.0 V, and the output voltage is regulated at 3.3V. According to the measured results, the maximal conversion efficiency is 97.8%.

Linear Quadratic Regulator and Fuzzy Control for Grid-Connected Photovoltaic Systems

This work presents a control scheme to control a grid-connected single-phase photovoltaic (PV) system. The considered system has four 250 W solar panels, a non-inverting buck-boost DC-DC converter, and a DC-AC inverter with an inductor-capacitor-inductor (LCL) filter. The control system aims to track and operate at the maximum power point (MPP) of the PV panels, regulate the voltage of the DC link, and supply the grid with a unity power factor. To achieve these goals, the proposed control system consists of three parts: an MPP tracking controller module with a fuzzy-based modified incremental conductance (INC) algorithm, a DC-link voltage regulator with a hybrid fuzzy proportional-integral (PI) controller, and a current controller module using a linear quadratic regulator (LQR) for grid-connected power. Based on fuzzy control and an LQR, this work introduces a full control solution for grid-connected single-phase PV systems. The key novelty of this research is to analyze and prove that the newly proposed method is more successful in numerous aspects by comparing and evaluating previous and present control methods. The designed control system settles quickly, which is critical for output stability. In addition, as compared to the backstepping approach used in our past study, the LQR technique is more resistant to sudden changes and disturbances. Furthermore, the backstepping method produces a larger overshoot, which has a detrimental impact on efficiency. Simulation findings under various weather conditions were compared to theoretical ones to indicate that the system can deal with variations in weather parameters.

Uncertainty Estimator based Sliding Mode Control Schemes for Multimode Noninverting Buck-Boost DC-DC Converter

A noninverting buck-boost dc-dc converter can be operated in buck, boost and buck-boost mode depending on an input voltage and desired output voltage. An input voltage must be known to operate the converter in these operating modes. In this paper, two methods are proposed to estimate uncertainties in input voltage and load resistance. First, state observer based adaptive law is designed to estimate the uncertainties. Based on the estimates, a pulsewidth modulation based sliding mode control is proposed to control the output voltage of the converter. Another uncertainty estimator scheme, namely, disturbance observer is proposed to estimate the uncertainties and then a pulsewidth modulation based sliding mode control technique is proposed. Both the proposed schemes are compared and their robustness to the uncertainties is proved by simulation in MATLAB/Simulink.

An improved integrated control modeling of a high-power density interleaved non-inverting buck-boost DC-DC converter

PurposeThis paper aims to propose a novel integrated control method (ICM) for high-power-density non-inverting interleaved buck-boost DC-DC converter. To achieve high power conversion by conventional single phase DC-DC converter, inductor value must be increased. This converter is not suitable for industrial and high-power applications as large inductor value will increase the inductor current ripple. Thus, two-phase non-inverting interleaved buck-boost DC-DC converter is proposed.Design/methodology/approachThe proposed ICM approach is based on the theory of integrated dynamic modeling of continuous conduction mode (CCM), discontinuous conduction mode and synchronizing parallel operation mode. In addition, it involves the output voltage controller with inner current loop (inductor current controller) to make a fair balancing between two stages. To ensure fast transient performance, proposed digital ICM is implemented based on a TMS320F28335 digital signal microprocessor.FindingsThe results verify the effectiveness of the proposed ICM algorithm to achieve high voltage regulating (under 0.01 per cent), very low inductor current ripple (for boost is 1.96 per cent, for buck is 1.1) and fair input current balance between two stages (unbalancing current less than 0.5A).Originality/valueThe proposed new ICM design procedure is developed satisfactorily to ensure fast transient response even under high load variation and the solving R right-half-plane HP zeros of the CCM. In addition, the proposed method can equally divide the input current of stages and stable different parallel operation modes with large input voltage variations.

Design of an Average-Current-Mode Noninverting Buck–Boost DC–DC Converter With Reduced Switching and Conduction Losses

With the rapid growth of battery-powered portable electronics, an efficient power management solution is necessary for extending battery life. Generally, basic switching regulators, such as buck and boost converters, may not be capable of using the entire battery output voltage range (e.g., 2.5-4.7 V for Li-ion batteries) to provide a fixed output voltage (e.g., 3.3 V). In this paper, an average-current-mode noninverting buck-boost dc-dc converter is proposed. It is not only able to use the full output voltage range of a Li-ion battery, but it also features high power efficiency and excellent noise immunity. The die area of this chip is 2.14 × 1.92 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , fabricated by using TSMC 0.35 μm 2P4M 3.3 V/5 V mixed-signal polycide process. The input voltage of the converter may range from 2.3 to 5 V with its output voltage set to 3.3 V, and its switching frequency is 500 kHz. Moreover, it can provide up to 400-mA load current, and the maximal measured efficiency is 92.01%.