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ABSTRACT In advanced processes, single‐inductor multiple‐output (SIMO) DC‐DC converters with battery voltage as input face serious overvoltage problems due to low MOSFET withstand voltage. To meet the needs of SIMO converter design in advanced processes, this paper first proposes a SIMO converter with an adaptive power supply buffer (APSB) and voltage‐limiting techniques in 22‐nm CMOS. The proposed APSB technology ensures that the driving voltage of the power stage remains unchanged under the changing power supply, solving the breakdown problem caused by low MOSFET withstand voltage and simplifying the circuit design of the power stage. The proposed voltage‐limiting techniques avoid the overvoltage of the internal circuit by using a special voltage‐limiting design for the VX2 node and output voltage during startup and steady state. The proposed SIMO is designed and validated under a 22‐nm CMOS process. The input power supply range is 2.8–5 V, and the three output voltages are 0.8, 1, and 1.8 V, respectively. The maximum load for each output voltage is 250 mA. The SIMO system achieves a peak efficiency of 92.2% over the full load range. [ABSTRACT FROM AUTHOR]

ABSTRACT This paper proposes a novel finite‐time adaptive continuous robust control method for buck converters, combining dynamic sliding mode theory with a mismatched disturbance observer. While traditional sliding mode control can effectively manage matched disturbances, it often falls short when faced with mismatched disturbances, potentially compromising system performance. Our developed control strategy introduces a nonlinear sliding mode‐based disturbance observer and an adaptive continuous robust sliding mode control to guide state variables towards desired values. To mitigate the chattering phenomenon, the proposed controller incorporates a super‐twisting algorithm, ensuring continuous control command behavior. We conducted a rigorous finite‐time stability analysis of the control procedure using Lyapunov theory. Furthermore, comprehensive experimental results demonstrate that our proposed control method significantly reduces disturbance effects and enhances the buck converter's performance in terms of robustness and accuracy. [ABSTRACT FROM AUTHOR]

In this study, we present the design, simulation, and implementation of a DC-DC synchronous buck converter utilizing IISB's 2 μ m 4H-silicon carbide (SiC) complementary metal–oxide–semiconductor (CMOS) technology. The converter is designed to meet the demands of modern integrated circuits, particularly in the field of integrated power management. The SiC technology offers enhanced performance and reliability at high temperatures, making it especially suitable for applications that operate in these conditions, including automotive systems, and aerospace, among others. The power transistors and gate drivers are fully integrated on-chip, optimizing efficiency and minimizing footprint. Additionally, the study contributes to the understanding of SiC technology and its application in integrated circuit design. Simulation results demonstrate a peak efficiency of 86.6% at 120 mA load current and 84.8% at 300 mA load current, showing the converter performance under different operating conditions. Furthermore, at high temperatures (295 °C), the converter achieves an efficiency of 89.6%, demonstrating its robustness and versatility in extreme environments. These findings contribute to the advancement of integrated circuit design and facilitate advancements in more efficient and robust power management solutions. [ABSTRACT FROM AUTHOR]

ABSTRACT This paper introduces a single‐phase step‐down AC‐AC converter designed for voltage sag/swell compensation applications. The converter features a minimal component count, continuous input current, and high efficiency, although only one power switch operates at a high frequency per input voltage half‐cycle. It offers a linear and broad voltage conversion ratio (D) without right‐half‐plane zeros in its small‐signal transfer function, simplifying the controller design. The proposed converter does not need dead time. It ensures balanced voltage and current stresses and power losses among power switches, easing the selection of semiconductors. Compared with existing topologies, it excels in total capacitor voltage, switching device power, and volume metrics of capacitors and inductors, thereby reducing cost and size. Experimental results from a 250‐W prototype demonstrate a peak efficiency of 94.8% and effective voltage sag/swell mitigation as a DVR. [ABSTRACT FROM AUTHOR]

Summary: In this paper, a new stacked bidirectional non‐isolated DC‐DC converter for uninterruptible power supply applications is presented. It is a stacked adaptation of the classical bidirectional boost/buck converter and presents improvements such as low number of components; low voltage and current stress on components; high efficiency; and simplicity of operation. In addition, in this paper, the modeling and control of the proposed converter are done, and a comparative evaluation among proposed converter with similar topologies is evaluated. A prototype of 1 kW, 144 to 400 V, is developed in laboratory to validate the theoretical evaluations of proposed converter. Besides that, the proposed converter is also evaluated under different dynamic condition, which illustrates the effectiveness of the converter. Finally, the maximum efficiency obtained is 96.38% in step‐up mode and 95.7% in step‐down mode. [ABSTRACT FROM AUTHOR]

The simplicity and cost of the control systems used in power converters are an urgent aspect. In this research, a simple and low cost voltage regulation system for a Buck converter system operating in uncertain conditions is provided. Using an electronic PID controller technique, the feedback control scheme of the presented Buck converter is carried out. Matlab software used a simulation environment for the proposed analog PID-based Buck converter scheme. The PID controller is easily implementable since it is built with basic and conventional electronic components like a resistor, capacitor and op-amp. The system simulation has high reliability as it is implemented using the Simscape package. The Simscape components used to build the converter system are modeled effectively taking into consideration including the practical factors such as internal resistance, tolerance and parasitic elements. This procedure certainly enhances the reliability of the simulation findings as the working conditions of the simulated system become more closer to the real-world conditions. Particle Swarm Optimization (PSO) is employed to properly optimize tune the PID gains. The regulation process of the PID control scheme is assessed under voltage and load disturbances in order to explore the robustness of the Buck converter performance. The findings from the system simulation, under the uncertainties, show largest rise time and settling time of 20 ms and 25 ms respectively, zero overshoot and minimum steady state error response, except at load disturbance case there is a fluctuation of 1 V. Consequently, It can be said that the proposed Buck converter based on analog PID controller can be used efficiently in the industrial and power applications. [ABSTRACT FROM AUTHOR]

This article presents a buck converter in which the inductor has been replaced by a transmission line. This approach would be practically conceivable if the power supply and load had a greater spatial distance. Alternatively, the model derived in this way could also be regarded as an intermediate model in order to replace a power coil via discretization with a larger number of smaller coils and capacitors. In the time domain, this new converter can be described by a system of coupled partial and ordinary differential equations. In the frequency domain, a transcendental transfer function is obtained. For comparison with an equivalently parameterized conventional converter, Padé approximants are derived. A linear controller is designed for the converter topology under consideration. [ABSTRACT FROM AUTHOR]

Selecting the appropriate charger for electric vehicles (EVs) is crucial for enhancing performance, with non-isolated DC-DC converters playing a significant role in charging EV batteries. The efficient conversion of input power into output as per the requirement is main perspective in the design of DC-DC converters. This paper delves into the landscape of non-isolated DCDC converters utilized in EV charging, emphasizing their pivotal role. Additionally, it introduces a novel approach by incorporating machine learning-based pulse width modulation (PWM) control for the buck DC-DC converter. By integrating machine learning algorithms into the control scheme, the efficiency and performance of the charging system can be greatly enhanced, resulting in improved overall EV operation. This innovative application of machine learning not only optimizes charging efficiency but also enables adaptability to varying input/output conditions, ultimately leading to more efficient and effective charging processes for EVs. [ABSTRACT FROM AUTHOR]

Li-ion batteries can be charged with different techniques according to the charging time and required capacity usage. Most charging techniques face difficulties when implemented in PV systems due to the intermittent and unpredictable nature of the power supply. This paper addresses the issue of determining the appropriate charging technique for Li-ion batteries in a PV system. We have developed a mode-selective control approach that determines the optimal charging mode according to the given SOC and solar irradiation, aiming to maximize the utilization of the generated PV power. The developed control approach has been implemented using a dual-switched buck converter in the MATLAB/Simulink environment. The key control algorithm focused on regulating current, with different references being used based on the selected charging mode. Three references for charging current were set: the maximum current, the required current assigned based on the given SOC, and the pulsed current. The pulsed current reference was employed during a stage of the charging process to accelerate charging and prevent dissipation of PV power. Furthermore, a gain-scheduled controller with carefully picked control parameters was used to ensure stable operation across different modes. The results proved the effectiveness of the proposed control in reducing charging time and minimizing PV power dissipation without resorting to the use of harmful charging currents.

This paper presents a comprehensive guide for the design and development of a power electronic converter, specifically focusing on the Buck converter. The guide aims to bridge the gap between theoretical knowledge and practical application, providing engineering students with a hands-on experience in digital control using the STM32 microcontroller. The workshop experience described covers all necessary steps, from the initial design and simulation using tools like MATLAB-Simulink and Plecs to the final implementation and testing of the converter. The educational value of this approach is highlighted, emphasizing the importance of practical engagement in understanding complex concepts related to power electronics. [ABSTRACT FROM AUTHOR]

This paper presents a highly efficient dual-mode HV (high voltage) buck converter which operates at both light and heavy load currents. To improve the conversion efficiency at two different load conditions, a dual-mode design composed of pulse width modulation (PWM) and pulse frequency modulation (PFM) were implemented using TSMC 0.5- $\mu $ μ m HV CMOS process. The chip area is 2038.05 $ \times $ × 1689.85 $\mu $ μ m2, while the input voltage ranges from 12 V to 15 V. A 92.95% peak efficiency at a load current of 10 mA was achieved based on on-silicon measurement results. [ABSTRACT FROM AUTHOR]

Summary: In this study, couple inductor‐based buck power factor correction (PFC) converter is designed to mitigate dead zones of the converter. To minimize switching losses, all switches are controlled using a soft switching method, eliminating the need for snubber circuits. The circuit is controlled by an analog UC3843 pulse width modulation (PWM) integrated circuit (IC), providing natural PFC capability, which simplifies control and offers advantages in terms of size and cost compared to conventional ones. Simulation studies and prototype implementation are carried out to evaluate performance of the topology. The converter operates within a voltage range of 90–280 Vrms and has a power rating of 150 W. The results from both simulation and experimental analyses indicate that power factor (PF) of the circuit exceeds 98% and total harmonic distortion (THD) of the input current is found to be below 5% under various input voltage and load conditions. Furthermore, proposed topology demonstrated high efficiency, with measurements of 93% at full load and 95.6% at half load under 220 Vrms input voltage and 80 Vdc output voltage conditions. Outcomes highlight that the proposed topology achieves pure sinusoidal input current and exhibits competitive performance compared to other topologies used in the industry. [ABSTRACT FROM AUTHOR]

As the most abundant element in the universe, hydrogen presents considerable potential as an energy carrier for the decarbonization of diverse economic sectors. The essential role played by Polymer Electrolyte Membrane (PEM) water electrolyzers (WEs) in enabling the production of green hydrogen through water electrolysis underscores their significance, owing to their rapid dynamic response and high energy efficiency. This study focuses on utilizing photovoltaic (PV) generated electricity for hydrogen production via Proton Exchange Membrane Water Electrolysis (PEMWE). During the electrolysis process, especially when generating hydrogen, there is a requirement for low voltage and high current levels. To regulate the output voltage from PVs, a buck converter has been employed. Nevertheless, optimizing the performance, efficiency, and operational lifespan of PEM WEs necessitates the application of robust control algorithms. The control system incorporates the Perturb and Observe (P&O) and Fuzzy Logic (FL) algorithms, with a comparative analysis of their respective outcomes. Simulation results indicate that the FL Controller exhibits superior efficiency and enhanced performance when compared to the conventional P&O method. • Solar energy is used to obtain clean energy. • Hydrogen is generated with electrolysis process. • DC-DC buck converter is used to reduce voltage and increase current for electrolysis. • The Perturb and Observe (P&O) and Fuzzy Logic (FL) algorithms are modelled to control. [ABSTRACT FROM AUTHOR]

In recent years, there has been a growing interest in using model-free deep reinforcement learning (DRL)-based controllers as an alternative approach to improve the dynamic behavior, efficiency, and other aspects of DC–DC power electronic converters, which are traditionally controlled based on small signal models. These conventional controllers often fail to self-adapt to various uncertainties and disturbances. This paper presents a design methodology using proximal policy optimization (PPO), a widely recognized and efficient DRL algorithm, to make near-optimal decisions for real buck converters operating in both continuous conduction mode (CCM) and discontinuous conduction mode (DCM) while handling resistive and inductive loads. Challenges associated with delays in real-time systems are identified. Key innovations include a chattering-reduction reward function, engineering of input features, and optimization of neural network architecture, which improve voltage regulation, ensure smoother operation, and optimize the computational cost of the neural network. The experimental and simulation results demonstrate the robustness and efficiency of the controller in real scenarios. The findings are believed to make significant contributions to the application of DRL controllers in real-time scenarios, providing guidelines and a starting point for designing controllers using the same method in this or other power electronic converter topologies. [ABSTRACT FROM AUTHOR]

This paper presents a novel single-phase non-isolated bidirectional buck converter topology. The proposed converter uses a basic switching cell structure with a coupled inductor and an interleaving switching scheme. This article addresses a crucial challenge in bidirectional DC-DC conversion by prioritizing reducing output current ripples and minimizing filter inductor size. The employed method includes using MOSFETs with fast recovery diodes to mitigate reverse recovery and body diode losses. Furthermore, the optimization of the switching frequency of the output inductor to be twice the actual switching frequency contributes to reducing the component size of the converter. The coupled inductor also helps to reduce stress on components by distributing currents among its legs. The experimental result demonstrates the proposed converter has a very low ripple current as compared to the conventional converter. The low current ripples and smaller filter inductor size enabled by high-frequency operation have improved the efficiency and size of the converter. A common ground between input and output terminals ensures robust performance without common mode current concerns. Overall, the proposed converter represents a significant improvement in DC-DC converters, promising enhanced efficiency, reliability, and compactness in bidirectional DC-DC conversion systems. In order to verify the performance of the proposed converter, a 460 W buck converter prototype was built and tested. [ABSTRACT FROM AUTHOR]

Li-ion batteries can be charged with different techniques according to the charging time and required capacity usage. Most charging techniques face difficulties when implemented in PV systems due to the intermittent and unpredictable nature of the power supply. This paper addresses the issue of determining the appropriate charging technique for Li-ion batteries in a PV system. We have developed a mode-selective control approach that determines the optimal charging mode according to the given SOC and solar irradiation, aiming to maximize the utilization of the generated PV power. The developed control approach has been implemented using a dual-switched buck converter in the MATLAB/Simulink environment. The key control algorithm focused on regulating current, with different references being used based on the selected charging mode. Three references for charging current were set: the maximum current, the required current assigned based on the given SOC, and the pulsed current. The pulsed current reference was employed during a stage of the charging process to accelerate charging and prevent dissipation of PV power. Furthermore, a gain-scheduled controller with carefully picked control parameters was used to ensure stable operation across different modes. The results proved the effectiveness of the proposed control in reducing charging time and minimizing PV power dissipation without resorting to the use of harmful charging currents. [ABSTRACT FROM AUTHOR]

This paper presents a novel fuzzy-augmented model reference adaptive voltage regulation strategy for the DC–DC buck converters to enhance their resilience against random input variations and load-step transients. The ubiquitous proportional-integral-derivative (PID) controller is employed as the baseline scheme, whose gains are tuned offline via a pre-calibrated linear-quadratic optimization scheme. However, owing to the inefficacy of the fixed-gain PID controller against parametric disturbances, it is retrofitted with a model reference adaptive controller that uses Lyapunov gain adaptation law for the online modification of PID gains. The adaptive controller is also augmented with an auxiliary fuzzy self-regulation system that acts as a superior regulator to dynamically update the adaptation rates of the Lyapunov gain adaptation law as a nonlinear function of the system's classical error and its normalized acceleration. The proposed fuzzy system utilizes the knowledge of the system's relative rate to execute better self-regulation of the adaptation rates, which in turn, flexibly steers the adaptability and response speed of the controller as the error conditions change. The propositions above are validated by performing tailored hardware experiments on a low-power DC–DC buck converter prototype. The experimental results validate the improved reference tracking and disturbance rejection ability of the proposed control law compared to the fixed PID controller. [ABSTRACT FROM AUTHOR]

This paper introduces a novel metaheuristic algorithm named the opposition-based cooperation search algorithm with Nelder–Mead (OCSANM). This enhanced algorithm builds upon the cooperation search algorithm (CSA) by incorporating opposition-based learning (OBL) and the Nelder–Mead simplex search method. The primary application of this algorithm is the design of a fractional-order proportional–integral–derivative (FOPID) controller for a buck converter system. A comprehensive evaluation is conducted using statistical boxplot analysis, nonparametric statistical tests and convergence response comparisons to assess the algorithm's performance and confirm its superiority over CSA. Furthermore, the FOPID-controlled buck converter system based on OCSANM is compared with two top-performing algorithms: one using a hybridized approach of Lévy flight distribution with simulated annealing (LFDSA) and the other employing the improved hunger games search (IHGS) algorithm. This comparison encompasses transient and frequency responses, performance indices and robustness analysis. The results reveal the notable advantages of the proposed OCSANM-based system, including 25.8% and 8.7% faster rise times, 26% and 8.8% faster settling times compared with the best-performing approaches, namely LFDSA and IHGS, respectively. In addition, the OCSANM-based system exhibits a 34.7% and 9.6% wider bandwidth than the existing approaches-based systems. Incorporating voltage and current responses of the buck converter's switched circuit with the OCSANM-based FOPID controller further underscores the algorithm's effectiveness. To provide a comprehensive assessment, the paper also compares the proposed approach's time and frequency domain responses with those of 17 other state-of-the-art approaches attempting to control buck converter systems similarly. These findings affirm the effectiveness of the OCSANM in designing FOPID controllers for buck converter systems. [ABSTRACT FROM AUTHOR]

Microgrids are designed to connect different types of AC and DC loads, which require robust power controllers to achieve an efficient power transfer. However, the effects of both AC and DC disturbances in the same type of controller make achieving stability a design challenge, especially in coupled systems where disturbances affect both the upstream and downstream in the microgrid. This paper presents an analysis of a second-order sliding-mode control (SOSMC) applied to a microgrid with direct-current (DC) and alternating-current (AC) power converters. The aim is to simulate the second-order sliding-mode control with buck converters that feed constant DC–DC and DC–AC power loads. The controller was tested in consideration of a unique sliding surface facing external disturbances, such as variations in the frequency of AC converters, sudden changes in upstream voltages, and constant power loads (CPL). The influence of the gain values (K) on the controller was also analyzed. The results show that the controller is robust regarding its sensitivity to external disturbances and steady-state error. However, the importance of the constant "K" in the model states that there exist K-limit values where if "K" is too low, a slowdown is presented, and the response against disturbances can be critical, and if is too high, an overshoot is presented in the output voltage. [ABSTRACT FROM AUTHOR]

Since voltage stress of semiconductors is equal to the input voltage in the conventional buck converter, the voltage stress of semiconductors is high in high input voltage application. In addition, ripple voltage across the output filter varies with the input voltage, so volume and weight of the output filter increases. Therefore, the buck converter integrated with a CDD circuit is proposed to address the aforementioned problems. Voltage stress of semiconductors is constant and is equal to the output voltage. Thus, voltage stress of semiconductors is reduced in the high input voltage application and efficiency of the system can be improved because of low voltage stress of semiconductors. In addition, ripple voltage across the output filter is also constant and is equal to the output voltage, so volume and weight of the output filter can be reduced when input voltage varies. Operating principle of the proposed converter is elaborated. Design guideline and examples are given. Loss of the converter is analyzed. Comparison among different buck-type converters is presented. Lastly, experimental results confirm the theoretical analysis. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This research aims to enhance the performance of photovoltaic (PV) systems on a 2-fold basis. Firstly, it introduces an advanced deep artificial neural network algorithm for accurate and fast maximum power point tracking, ensuring optimal extraction of electrical power from PV arrays. Secondly, it proposes the use of 96-V, 2.98-kW direct-current (DC) water pumps for farm irrigation, aiming to improve efficiency, reduce cost and complexity, and overcome challenges associated with connecting faraway farm irrigation systems to the utility grid. In this study, it has been demonstrated that the use of DC pumps greatly improves system performance and efficiency by eliminating the need for isolation transformers, power passive filters and inverters, therefore simplifying the architecture of the system. The efficacy of the proposed methodology is confirmed by MATLAB®/Simulink® simulation results, whereby the proposed algorithm attains a mean squared error of 6.5705 × 10–5 and a system efficiency approaching 99.8%, ensuring a steady voltage under varying load conditions. [ABSTRACT FROM AUTHOR]

This paper offers the first demonstration of the design and layout of a fully integrated power converter in a monolithic Silicon Carbide (SiC) technology. A 400 V Buck Converter integrated with Gate-Drivers and Low-Voltage Control circuitry in a 25–600 V Mixed-Mode SiC CMOS technology has been presented in this paper. A new SiC technology has been developed for this design which has a feature size of 1 μm. This technology allows integration of High-Voltage Power FETs and Low-Voltage CMOS circuits on the same die with a common substrate. Both high-side and low-side Power FETs are N-type hence a bootstrap circuit is used, and the gate drivers use an isolated capacitive level shifter to translate the signals from the 25 V domain to the 400 V domain which is the input voltage of the Buck Converter. The load current is 1 A and the nominal output voltage is 100 V thereby meaning that the output power is 100 W. The switching frequency is up to 1 MHz, and the duty cycle can range from 10% to 90% signifying a wide range of operation of the converter. [ABSTRACT FROM AUTHOR]

This paper emphasizes the significance of implementing an effective control system to enhance the performance of a three-stage DC–DC buck converter (TDDC). Herein, we present the development of an observer controller (OC) for TDDC, where average modeling of the DC–DC converter was employed alongside an observer algorithm for the OC. The primary focus is on the adoption of an observation topology aimed at enhancing system responsiveness under various conditions, including variable input voltages, reference voltage changes, load fluctuations, integration with photovoltaics, and battery charging. This approach ensures improved stability and performance, addressing the dynamic challenges inherent in such systems. A comparative analysis was conducted on two distinct control topologies for the proposed TDDC system, namely proportional–integral (PI) and advanced OC. Simulink software was used to model and simulate the proposed system. The results demonstrate lower rising and settling times of the TDDC for the OC and PI implementations, respectively. Additionally, the system with the OC eliminates 20% of the overshoot, while the system with OC minimizes the output voltage oscillations from 13% to 2% compared to the PI system. The OC was integrated into the TDDC to enhance system stability and improve the control loops, particularly the third loop. These improvements make the TDDC with OC suitable for application to renewable energy systems, microgrids, telecommunication networks, and electric vehicles, where precise control and stability are essential.

The ability to manage abrupt disturbances in input supply voltage and sudden fluctuations in load represents a fundamental requirement for DC‐DC buck converters. While feedback control systems typically address such transients, certain applications necessitate even faster transient responses. This paper introduces an input voltage feedforward scheme (IVFS) integrated with voltage mode feedback controllers to enhance closed‐loop performance. Relevant transfer functions resulting from the inclusion of the feedforward circuit are derived, and an optimal condition for audio susceptibility nullification is identified. This scheme ensures an additional 30dB$$ 30\kern0.1em \mathrm{dB} $$ attenuation in magnitude of audio susceptibility, in contrast to the buck converter without feedforward. In the time domain, the incorporation of IVFS results in a 20% reduction in percentage overshoot for a 12‐8‐12 step in supply voltage. Additionally, for a 12‐15‐12 step, the percentage overshoot and settling time are completely eliminated. Various active and passive parasitics are included in modeling of the buck converter to aid in designing the feedforward and feedback controller. A Type‐III controller is employed as a feedback controller to assess the closed‐loop performance. A hardware prototype is built to demonstrate the efficacy of the proposed feedforward scheme. The implementation of the entire circuit is straightforward due to its requirement of only a few discrete components, namely, analog multiplier, and error amplifier. [ABSTRACT FROM AUTHOR]

Summary: This study proposes a new design for a non‐isolated buck converter with continuous input current. As required, the integration of additional modules into the existing structure permits a significant decrease in the converter's gain to attain significantly lower values. In order to create the proposed converter, the input voltage connections to the Ćuk converter were changed. In this configuration, the operational state of the Ćuk converter has been changed from buck‐boost to step‐down by connecting the input power source's negative polarity to the inductor's terminal. In addition, the proposed converter benefits from a common ground between the input source and output port. Moreover, it can achieve a significant reduction in gain by increasing the number of series modules. Finally, the compact converter was smoothly incorporated onto a printed circuit board (PCB) and afterward validated by an output power of 80 watts. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The presence of uncertainty in the converter model and controller parameters affects the system's stability and dynamic performance. This paper presents a comparative analysis of robust non‐fragile control based on (i) the Kharitonov method and (ii) the linear matrix inequality (LMI) technique so that the controller can cope with the effect of both uncertainties. The first approach based on Kharitonov theorem determines the robust performance region with guaranteed gain margin and phase margin under parametric uncertainty. The second approach (LMI technique) is based on devising a control law that can quadratically stabilize the closed‐loop system subject to uncertainties and satisfy the H∞ norm bound constraint on disturbance attenuation. Based on these two approaches, a robust non‐fragile PI controller is designed for voltage mode control of dc‐dc buck converter. The effectiveness of the control approaches is evaluated based on (i) robustness against large plant parameter perturbations and load disturbance and (ii) fragility against controller parameter perturbations. The performance of the designed controllers (using the Kharitonov method and the LMI technique) has been thoroughly evaluated and validated through simulation and experimental results. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive exploration of an integrated Buck-Boost converter and Sliding Mode Control (SMC) Maximum Power Point Tracking (MPPT) system for optimizing photovoltaic energy conversion. The study focuses on enhancing solar energy extraction efficiency, regulating output currents, and ensuring effective battery utilization. Through a systematic analysis of converter component sizing and operational modes, the paper delves into the intricacies of the Buck-Boost converter. The unique contribution lies in the innovative integration of SMC with the traditional Perturb and Observe (P&O) algorithm, providing robust and adaptive MPPT under varying environmental conditions. Additionally, the paper introduces a battery management system with three distinct modes, namely, Charging, Direct, and Discharging, offering intelligent control over critical scenarios. Simulation results underscore the robustness of the proposed system under diverse conditions, demonstrating its effectiveness in managing power distribution based on battery charge levels, even in scenarios of insufficient solar power. Overall, this research significantly contributes to advancing the understanding of PV/battery systems and offers a practical, sustainable solution for optimizing energy production, distribution, and storage, marking a substantial stride towards a more efficient and sustainable energy future. [ABSTRACT FROM AUTHOR]

This paper introduces a novel direct current to direct current (DC-DC) buck converter that uses a pseudo-current hysteresis controller and an on-chip soft start circuit for improved transient performance in automotive applications. The proposed converter, implemented with Taiwan semiconductor manufacturing company (TSMC) 0.18 µm complementary metal oxide semiconductor (CMOS) one-poly-six-metal (1P6M) technology, includes a rail-to-rail current detection circuit and an on-chip soft start circuit to handle transient responses and improve efficiency. Transient response analysis shows fast settling times of 28 µs for both load current changes from 100 mA to 1 A and reversals with consistent transient voltages of approximately 190 mV and peak power efficiency of 99.32% at 5 V output voltage and 100 mA load current. Additionally, the converter maintains a constant output voltage of approximately 5 V across the entire load current range with an average accuracy of 90.41%. A comparative analysis with previous work shows superior performance in terms of figure of merit (FOM). Overall, the proposed pseudo-current hysteresis controlled buck converter exhibits remarkable transient response, load regulation and power efficiency, positioning it as a promising solution for demanding applications, particularly in automotive systems where precise voltage regulation is crucial. [ABSTRACT FROM AUTHOR]

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents an elitism-crossover barnacle mating optimization (ECBMO). It is an improvement of barnacle mating optimization (BMO). The original BMO suffers from local optima problem leading to a low accurate solution. A new method of offspring generation is adopted into the original BMO structure. Some features of the best-so-far solution are incorporated into the generated offspring. The accuracy performance of the proposed algorithm is tested on several IEEE functions. A statistical analysis is conducted to compare its performance over the original BMO. It is also applied to optimize proportional integral derivative (PID) parameters for controlling output voltage of a buck converter. Result of benchmark functions test shows the proposed algorithm has attained higher accuracy for all functions compared to BMO algorithm. Application on the real problem shows both algorithms control the converter voltage satisfactorily. However, the ECBMO has achieved more optimal PID parameters and leading to a better output voltage response. [ABSTRACT FROM AUTHOR]

Recently, the stability of DC microgrids has attracted increasing attention. The traditional stability analysis method cannot not meet the requirements for the complexity and bidirectional energy flow of the system. In this paper, a passivity-based stability criterion (PBSC) is proposed to analyze the stability of the cascade system. In order to realize the passivity of the system, an improved feedback control method based on the traditional double-loop control strategy is proposed, which will improve the stability region and guarantee the passivity of the system. Moreover, a Buck-CPL simulation model is established based on MATLAB/Simulink R2008, and the correctness of the theoretical analysis is verified by experiments. [ABSTRACT FROM AUTHOR]

IoT and wearable medical devices frequently require ultra-low power solutions that can support long spells of inactivity. This study presents a buck converter to control power stages using a novel pulse frequency modulation (PFM) system that reduces switching losses for low-power systems. The modulation of high and low-frequencies was demonstrated, where the high-frequencies exhibited better energy transformation between the inductor and capacitor, and the low-frequencies could be adjusted for different current loads, to reduce switching losses. This circuit is optimized for light load applications. Using voltage control oscillation (VCO), the frequency range of 0.5 MHz – 2.0 MHz can be adjusted to influence conversion efficiency for different loads. The design was simulated and then fabricated using TSMC 0.18um process. The core size was about 1500 × 1000um that includes power MOS. Measurements result an average conversion efficiency of 91% under a load of 0.1 mA – 10 mA. This chip is suitable for battery-based IoT systems, or wearable medical devices. [ABSTRACT FROM AUTHOR]

This research focuses on evaluating and comparing different DC-DC converter designs, specifically for low power applications. The study considers inductor-based, switching capacitor, and linear voltage regulator (LVR) DC-DC converters. While there has been critical investigation of DC-DC converters in the literature, there is a gap in assessing their performance based on a comprehensive set of conflicting parameters. Additionally, there is a lack of research on matching the most suitable DC-DC converter with specific low power applications. The chosen application for this study is a DC-DC converter on a glass substrate, specifically for smart glass in electric vehicles. The research presents a complete process that includes design, simulation, layout, fabrication, and measurement. Through simulations, a 4.8 V to 3.3 V buck converter is recommended, demonstrating an almost ideal response time and minimal output ripples. Experimental measurements also confirm a low output ripple of 0.3 %. By addressing this research gap and providing a comprehensive evaluation of DC-DC converters, this study contributes to the development of efficient and reliable power solutions for smart glass applications in electric vehicles.

This study comprehensively analyzes the discontinuous conduction mode (DCM) of a two-phase interleaved buck converter (IBC) with an inversely coupled inductor (ICL). With ICL, nine circuit configurations are possible when the IBC operates in the DCM. Depending on the duty ratio and load condition, DCM can also be classified into seven types. Each type of DCM has a corresponding combination of circuit configurations. Consequently, the application of the combinations for distinguishing DCM types is proposed to analyze the DCM operation of two-phase IBCs with ICL. Different DCM types have different DCM characteristics, such as state space averaged models and time interval calculations, which are needed to be analyzed for small-signal modeling. Therefore, the state space averaged models and time intervals equations are derived for each DCM type, and boundary conditions between adjacent DCM types are analyzed. Experimental tests on the hardware prototype of the IBC are conducted to verify the practical effectiveness of the proposed analysis.

With the surging demands for higher current at sub-1-V supply level in high-performance digital systems, high-efficiency and high-current-density power converters are essential for system integration. Higher voltage supply buses are emerging for high-current applications to reduce the IR losses on the power delivery networks. Thus, there is a wide voltage gap between the power bus and the digital supply rails at the point of load (PoL). Meanwhile, battery-powered portable or wearable devices favor extremely high-power-density solutions, calling for novel power conversion topologies, which have been the hottest topic in the power management IC area in the past decade. This article reviews the switched-capacitor-inductor (SCI) hybrid dc–dc buck converters from the topology “seeds” to their “leaves.” Here, we define six seeds, they are: 1) three-level buck; 2) double-step down buck; 3) inductor-first buck; 4) always-dual-path buck; 5) buck–buck; and 6) multiple-output hybrid buck. We try to analyze and summarize their pros and cons, and to derive the evolution of the hybrid dc–dc converters, with milestone examples. Then, we share our observations, design intuitions, and suggestions to help the researchers and engineers to pick up and design a new SCI hybrid dc–dc converter.

The DC-DC converters are essential in power electronics as they maintain a stable output voltage even when there are changes in input voltage and load current. This study introduces an advanced Proportional-Derivative (PD) compensator for buck converters. The compensator enhances stability and transient responsiveness by employing a unique modulation technique that has not been previously applied in this context. The proposed method entails applying an input of 28 volts, which yields an output amplification of 15 volts, even in the presence of interference. The small signal transfer function of the buck converter is meticulously derived, considering the converter’s dynamic behavior to achieve exceptional results. The transfer function comprehensively explains the intricate relationship between the input and output voltages, providing the theoretical basis for our distinctive control approach. The MATLAB code accurately generates the Bode diagram of the buck converter by employing the small signal transfer function. The graph illustrates the frequency response of the converter, a crucial factor in enhancing the stability and quality of the output voltage. The proposed research is substantiated by mathematical data shown through several simulated figures, distinguishing it from conventional methodologies. The implemented research achieves the maximum efficiency exceeding 95% with a minimum ripple factor.

DC-DC buck converters in automotive and aerospace applications are often required to handle large disturbances in their input supply and abrupt variations in their loads. This paper proposes a systematic method to combine input-voltage feedforward (IVFF) and voltage-mode feedback (VFB) controllers, aiming to enhance the closed-loop performance of these DC-DC converters. This method relies on the stability boundary locus approach to help select the proper control parameters that achieve strong dynamic stability across the full operating range regardless of practical implementation challenges. Also, an optimization approach is employed to minimize the passive components’ area within the compensator, achieving a 79% reduction in integration size compared to conventional designs. The controller was fabricated in a 0.35- $\mu \text{m}$ CMOS technology, occupying a core area of 0.438 mm2. The prototype chip was experimentally tested to regulate a buck converter that leverages an e-GaN half-bridge while operating at 1 MHz. Measurement results show a remarkable closed-loop performance against line and load variations, reaching up to ±80 V/ms and ±535 mA per 150 $\mu \text{s}$ , respectively. The output remains stable, showcasing very small ( $ < 100\mu \text{s}$ ) with small overshoots (

Electromagnetic noise emission is inevitable in a DC-DC converter due to the employed switching technique. In low frequency, the noise propagating through cabling and conductive media is called a conducted emission. A conducted emission consists of differential mode and common mode noise. It is advantageous to know an estimate of emission level for each mode during the design phase so that suitable mitigation can be included earlier.. This paper aims to focus on a method to estimate the differential mode noise emission of a DC-DC converter. The estimation is computed using the input capacitor complex impedance and the current that flows through it. As a study case, a boost and buck converters are used for evaluation. The estimation and measurement results are compared. Despite differences at some frequencies, the estimated and measured results generally agree well. Because of its simplicity, the proposed method can be used as a practical tool in the EMC aspect of DC-DC converter design.