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AbstractOn one hand, determining the exact number of explanatory variables in uncertain regression analysis is often challenging, as real-world scenarios are interconnected. On the other hand, it’s worth noting that even when the number of variables is determined, some variables may have minimal impact on the response variable, and retaining them would only increase the complexity of the model. Therefore, variable selection methods can help eliminate variables with minimal impact to enhance the simplicity and interpretability of the model. In light of this, this paper first introduces a novel variable selection strategy based on the elastic net method to address the variable selection problem in uncertain regression models. This method not only offers the flexibility to simplify uncertain regression analysis into Lasso estimation or Ridge estimation but also exhibits extremely high efficiency in variable selection. Secondly, to address the issue of determining tuning parameters, we introduce the cross-validation method to ensure optimal model performance. Furthermore, we propose an uncertain hypothesis testing method based on imprecise observational data, which can help us assess the suitability of estimated parameters. Finally, through a series of numerical examples, we validate the feasibility and effectiveness of this method. [ABSTRACT FROM AUTHOR]

Wireless power transfer (WPT) systems typically operate under broad coupling conditions. In response to the issue of significant fluctuations in output power due to changes in the coupling coefficient when the coupling coils are offset, this paper proposes a parameter design method for the LCC‐S topology that remains applicable under dual‐side‐detuned conditions. Presented the design principles of the dual‐side‐detuned circuit, and an iterative approach is employed to guide the parameter design process. It also introduced a method for selecting the rated coupling coefficient to minimize power fluctuations within the expected range. Experimental validation demonstrates that the robustness and resistance to coupling coefficient fluctuations of the proposed dual‐side‐detuned LCC‐S topology surpass those of other candidate schemes. Within a coupling variation range from 0.23 to 0.35, the maximum fluctuation rate of the output power remains below 6% while maintaining acceptable efficiency. This design has relevance to typical application scenarios. [ABSTRACT FROM AUTHOR]

Due to the intrinsic limitations, for example, limited adjustment freedom, the traditional wireless power transfer (WPT) systems cannot maintain high efficiency under variable loading conditions. To well solve this problem, a family of general magnetically coupled resonant WPT (MCR‐WPT) compensation topologies composed of LCC‐C with an n‐stage LC structure, or LCC‐C(CL) n, is proposed in this paper. Under the guideline of the generalized structure, some existing topologies are derived for verification, with new topologies established with unique advantages. From the LCC‐C(CL) n structures, a suitable topology can be selected to achieve a desired design purpose, such as constant voltage transmission, constant current transmission, or high‐efficiency transmission. Prototype experiments and comparisons are conducted in this work, which demonstrate the effectiveness and applicability of the proposed LCC‐C(CL) n MCR‐WPT converter family and the parameter design method. Experimental results also show that the new topology can maintain high‐efficiency power transfer for a wide range of loads. Even under light loading conditions, the power transfer efficiency is 30% higher than the traditional benchmark topology. The proposed WPT approach will have wide applications for on‐road wireless electric vehicle charging. [ABSTRACT FROM AUTHOR]

Summary: The modeling of high‐order converter systems and design of their closed‐loop controllers are difficult due to their high nonlinearity, hence high‐order systems, large number of zero‐poles, and complex frequency‐domain characteristics. To ease the design methodologies, this paper studies high‐order power converters and proposes a modeling and control method for such converter systems with order reduction. As an example, the 7th‐order non‐electrolytic capacitor‐I‐Z‐Source converter (NEC‐I‐ZSC) is employed to implement the proposed design method. Operational analysis and small signal modeling of the NEC‐I‐ZSC are conducted, and a reduced‐order controller is then devised. Experimental verification is conducted, which prove the feasibility and effectiveness of the proposed design method. [ABSTRACT FROM AUTHOR]

The uncertain vector autoregressive model is able to model the interrelationships between different variables, which is more advantageous compared to the traditional autoregressive model, when modeling real-life objects and where the observed values are imprecise. In this paper, the parameters of the uncertain vector autoregressive model are estimated by using least absolute deviation estimation (LAD) to obtain a fitted uncertain vector autoregressive model, and residual analysis is performed to obtain estimates of expected values and variances of the residuals. In addition, future values are modeled by using forecasting methods, i.e., point estimation and interval estimation. The order of the uncertain vector autoregressive model is also determined by the indicator summation of test errors (STE) in the cross-validation, and we also analyze that the least absolute deviation estimation outperforms the least squares estimation method in the presence of outliers. [ABSTRACT FROM AUTHOR]

Adding time delay to nonlinear systems can significantly improve their performance, making it possible to construct image-encryption algorithms with higher security. In this paper, we propose a time-delayed nonlinear combinatorial hyperchaotic map (TD-NCHM) with a wide hyperchaotic interval. Based on TD-NCHM, we develop a fast and secure image-encryption algorithm that includes a plaintext-sensitive key-generation method and a simultaneous row-column shuffling-diffusion encryption process. Plenty of experiments and simulations demonstrate the superiority of the algorithm in terms of efficiency, security, and practical value in secure communications. [ABSTRACT FROM AUTHOR]

Solving uncertain differential equations is a critical subject in the field of uncertainty theory, where uncertain differential equations are a sort of differential equations that involve Liu processes. Currently, considerable effort has been put into addressing this issue. Regrettably, analytic solutions to uncertain differential equations are not always accessible. As a result, several numerical methods have been investigated. However, numerical methods have certain limitations in terms of providing a continuous representation of the solution as well as more information about the solution. This paper will propose a novel algorithm based on the variational iteration method (VIM) for solving uncertain differential equations analytically or approximately analytically. The associated numerical experiments show that the proposed method is an efficient tool for solving uncertain differential equations. [ABSTRACT FROM AUTHOR]

Multi-dimensional uncertain differential equations (MUDEs) are often used to describe complex systems that vary with time. In this paper, the generalized moment estimation method is employed to estimate the MUDEs' unknown parameters. A method to optimize parameters with multiple estimation results is proposed. The hypothesis test and α-path are proposed to verify the feasibility of the parameter results. Several examples of parameter estimation for MUDEs are given, as well as two numerical examples to verify the feasibility of the method. [ABSTRACT FROM AUTHOR]

Rainy degeneration damages an image's visual effect and influences the performance of subsequent vision tasks. Various deep learning methods for single image deraining have been proposed, obtaining appropriate recovery results. Unfortunately, most existing methods ignore the interaction between rain-layer and rain-free components when extracting relevant features, leading to undesirable results. To break the above limitations, we propose a progressive hybrid-modulated network (PHMNet) for single image deraining based on the two-branch and coarse-to-fine framework. Specifically, a hybrid-modulated module (HMM) with a two-branch framework is proposed to blend and modulate the feature of rain-free layers and rain streaks. After cascading several HMMs in the coarsest reconstructed stage of the PHMNet, a multi-level refined module (MLRM) is adopted to refine the final deraining results in the refined reconstructed stage. By being trained using loss functions such as contrastive learning, the PHMNet can obtain satisfactory deraining results. Extended experiments on several datasets and downstream tasks demonstrate that our method performs favorably against state-of-the-art methods in quantitative evaluation and visual effects. [ABSTRACT FROM AUTHOR]

A single-switch N-stage Z-network high-gain boost converter is proposed in this study, which can be applied in the field of chip etching for bias provision. The circuit topology, operation mode, voltage gain and the control strategy are analyzed. Thereafter, the steady-state performance of the circuit is analyzed with small signal stability modeling. A simulation model is built using Simulink and compared with the traditional quadratic circuit. Combined with the control strategy, the circuit can obtain better steady-state performance by controlling the number of working N-networks and adjusting the duty ratio in the case of high voltage, wide range of voltage output and dynamic voltage output. The simulation model and hardware prototype of the single-switch four-stage Z-network high-gain boost circuit are built and tested, which have verified the effectiveness of the proposed design. [ABSTRACT FROM AUTHOR]

The VIENNA rectifier is of high reliability, high power density, and low complexity, which has been widely applied in telecommunication systems. However, it has 25 switching states complicating the control design. Besides, it is easy for the VIENNA rectifier to distort the input currents at zero‐crossing points, which will degrade the grid power quality. To address these problems, a novel mode‐reduction space vector pulse width modulation (SVPWM) control method is proposed in this paper. By analyzing the switching states of the VIENNA rectifier, 3‐mode, 6‐mode, and 18‐mode control framework are compared, and it is found that the 18‐mode has advanced features. Specifically, the proposed 18‐mode control algorithm will have fewer calculation steps and a simpler processing flow. More importantly, it can eliminate the input current distortions for power quality improvement. A 4 kW hardware prototype of the VIENNA rectifier is developed, and experiments have been performed to verify the harmonic reduction feature of the proposed 18‐mode control. [ABSTRACT FROM AUTHOR]

With the development of signal processing technology, the ubiquitous Wi-Fi devices open an unprecedented opportunity to solve the challenging human gesture recognition problem by learning motion representations from wireless signals. Wi-Fi-based gesture recognition systems, although yield good performance on specific data domains, are still practically difficult to be used without explicit adaptation efforts to new domains. Various pioneering approaches have been proposed to resolve this contradiction but extra training efforts are still necessary for either data collection or model re-training when new data domains appear. To advance cross-domain recognition and achieve fully zero-effort recognition, we propose Widar3.0, a Wi-Fi-based zero-effort cross-domain gesture recognition system. The key insight of Widar3.0 is to derive and extract domain-independent features of human gestures at the lower signal level, which represent unique kinetic characteristics of gestures and are irrespective of domains. On this basis, we develop a one-fits-all general model that requires only one-time training but can adapt to different data domains. Experiments on various domain factors (i.e. environments, locations, and orientations of persons) demonstrate the accuracy of 92.7% for in-domain recognition and 82.6%-92.4% for cross-domain recognition without model re-training, outperforming the state-of-the-art solutions. [ABSTRACT FROM AUTHOR]

Summary: The slow balancing speed of switched‐capacitor (SC)‐based equalizers makes this structure difficult to apply in series‐connected battery strings. In order to reduce the number of energy conversion processes and achieve leapfrog transmission of energy, a hybrid‐structured voltage equalizer (HSVE) is developed in this work for battery strings to achieve high‐speed any‐unit‐to‐any‐unit (AU2AU) equalization, in which each unit can also achieve internal balance in any arbitrary imbalance status. Compared to the conventional equalizers using complex monitoring and control strategy, the proposed equalizer does not need any cell monitoring circuits—all MOSFETs are triggered by a pair of complementary pulse signals with a fixed switching frequency and constant duty ratio, and electricity can automatically and directly exchange among all battery cells. Hardware experiments on super‐capacitors and Li‐ion batteries are conducted in this study, which prove the feasibility of the proposed voltage equalizer. The proposed battery management strategy will have wide applications in modern battery‐related industries such as electric vehicles (EVs). [ABSTRACT FROM AUTHOR]

Low-light image enhancement, fundamentally an ill-posed problem, seeks to simultaneously provide superior visual effects and preserve the natural appearance. Current methodologies often exhibit limitations in contrast enhancement, noise reduction, and the mitigation of halo artifacts. Negative feedback pulse coupled neural network (NFPCNN) is proposed to provide a well posed solution based on uniform distribution in contrast enhancement. The negative feedback dynamically adjusts the attenuation amplitude of neuron threshold based on recent neuronal ignited state. Neurons in the concentrated brightness area arrange smaller attenuation amplitude to enhance the local contrast, whereas neurons in the sparse area set larger attenuation amplitude. NFPCNN makes up for the negligence of pulse coupled neural network in the brightness distribution of the input image. Consistent with Weber–Fechner law, gamma correction is employed to adjust the output of NFPCNN. Although contrast enhancement can improve detail expressiveness, it might also introduce artifacts or aggravate noise. To mitigate these issues, the bilateral filter is employed to suppress halo artifacts. Brightness is used as coefficient to refine the Relativity-of-Gaussian noise suppression method. Experimental results show that the proposed method can effectively suppress noise while enhancing image contrast. [ABSTRACT FROM AUTHOR]

The boom of electric vehicles (EVs) has urged new designs and applications of power conversion technologies. Power converters, as one of the most critical components in EV battery systems, have seen significant developments in recent years. However, thus far forward design approaches for power converter topologies have been widely adopted, which are based on engineers’ empirical knowledge and instinct. This has been deemed having low design efficiency with high randomness and limited applicability, due to the absence of a systematic guideline. This approach, though widely adopted, can no longer meet the increasingly stringent and diverse needs of today’s research and industry, with the emerging trend of renewable energy sources. Aware of these drawbacks, in this study, we propose a novel reverse design approach through establishing general polynomial relations between the topology and voltage gain of high-step-up converters, which are found to be functions of basic boost converters’ voltage gains. With this newly formed polynomial relation, a generalized approach to devising power converters for various industrial needs can be derived, which is baptized the General Polynomial Reverse Design (GPRD) approach. Three polynomial converters are derived as examples to validate the proposed method, whereby their functionality and performances are verified and tested by prototype experiments, which substantiate the proposed design theory. [ABSTRACT FROM AUTHOR]

A novel Cuk-based bridgeless rectifier is proposed for receiving side of wireless power transfer (WPT) system. The proposed converter can not only help improve overall efficiency but also is with features of wide power modulation range and very low output current ripple. In terms of the output current source characteristics of series-series-compensated WPT system, a bridgeless rectifier and a Cuk converter are combined and an input inductor of Cuk converter is cut down to form the proposed single-stage converter. Besides, a synchronization operation method is derived for the proposed converter to realize the optimal working point of transmission power and efficiency. Operation principles of the converter and its impact on performance of WPT system are analyzed. Also, design methods for system parameters are given. A prototype is built up to verify the feasibility of the proposed topology and the operation method. It is noted that the proposed converter can well adjust the output power of WPT system to realize the desired working point via adjusting the duty cycle at different transfer distances and loads. [ABSTRACT FROM AUTHOR]

Proposed in this letter is a novel generalized method to replace all short-life and large-size electrolytic capacitors (ECs) with non-ECs (NECs) in step-up converters. NEC has a longer lifespan and smaller size, leading to extended converter life and reduced converter size. The proposed approach can systematically replace ECs with NECs without affecting the desired converters’ output features. After theory elaboration, five representative converters in two schemes are built with ten $150\,\mathrm{W}$ / $100\,\mathrm{V}$ high power density prototypes for experimental verification. Experiments show that these prototypes can reach maximum power density of $2.91\,\mathrm{W/cm^3}$ , significantly higher than converters with ECs, and maximum efficiency of 95.64%. [ABSTRACT FROM AUTHOR]

This article develops a series of improved Z-source dc–dc converters to realize additional voltage pumping and high power density through two propositions. Proposition 1 develops two improved positive- and negative-connected Z-source dc–dc converters (IPZSC and INZSC), using the same number of components as in the existing voltage pumping Z-source converter. Based on Proposition 1, Proposition 2 proposes four novel embedded Z-source dc–dc converters (EZSCs) by placing the source in a specifically designed position, which realizes lower voltage stresses across capacitors. Various technical aspects of the proposed EZSCs, including operations, power losses, and small signal stability analyses are detailed in this paper. Besides, comparisons between the proposed series of improved Z-source dc–dc converters and other existing Z-source dc–dc converters are thoroughly made to demonstrate the better performance of the EZSCs. Finally, experiments are conducted to well validate the effectiveness and superiority of the proposed converter circuits. [ABSTRACT FROM AUTHOR]

Stochastic, nonlinear and time-varying factors bring great challenges to accurate modeling and design of real-time (RT) energy management systems (EMSs) for modern energy systems with intermittent renewable energy sources. In this paper, we propose a novel model-free RT-EMS based on the predictive adaptive dynamic programming (ADPredictive) algorithm for energy scheduling problems in a home EMS environment. The proposed RT-ADPreditive EMS can minimize the total cost of electricity, reduce battery life loss, and maximize the utilization of renewable energy generation. In the proposed RT-ADPredictive EMS, the gated recurrent unit (GRU) neural network (NN) is employed to perform online prediction of renewable energy generation and load consumption of the household based on RT data. The RT-ADPreditive algorithm can approximate the performance index function and the optimal control law based on the RT data and predicted data for the next time step. Convergence of the proposed method is mathematically proven, and a hardware-in-the-loop (HIL) experimental platform comprising dSPACE and RT-lab is built to verify the effectiveness of the proposed RT-ADPreditive home EMS. [ABSTRACT FROM AUTHOR]

The efficiency and safety issues caused by cell differences are the key factor to hinder the use of retired batteries. The reconfigurable battery technique is an effective method to break through the bottleneck. However, the potential short-circuit paths increase exponentially with the number of cells, which makes manual analysis unapplicable and brings serious risks in large scale reconfigurable battery systems. Existing researches are about topology and energy efficiency optimization, but the problem of short circuit is ignored. In this article, a systematic approach based on the sneak circuit theory is proposed to fundamentally avoid the short-circuit problem of reconfigurable battery systems. A novel sneak circuit theory based approach is creating a short circuit path table, which will be indexed to avoid connecting the anode and cathode of a battery cell/string. In addition, all the paths are further studied and analyzed, and the simplest path table can be obtained to improve the energy efficiency. To validate the theoretical foundation and feasibility of proposed approach, a reconfigurable battery system containing two kinds of batteries is developed. All experimental results well verify the effectiveness and feasibility of proposed approach. This work provides theoretical foundation for avoiding short-circuit paths in reconfigurable battery systems, which will break through the bottleneck in scale application. [ABSTRACT FROM AUTHOR]

Summary: A novel boost converter is proposed in this study, which is based on a newly designed impedance network, instead of using the traditional Z‐network structure and large electrolytic capacitors (ECs) to suppress current ripples. Besides, the proposed topology has ripple‐free output current, which is designed to improve the output current quality of the traditional boost converter and to enhance the voltage conversion ratio compared to the traditional Z‐network boost converter. The newly proposed impedance network consists of two inductor and capacitor (LC) pairs—one LC pair function as the intermediate energy transferring branch and the other pair as the output branch to obtain non‐pulsating output current. The operating principle and performance of the proposed converter are analyzed in detail for demonstrating its advanced features. Furthermore, the feasibility of the proposed converter topology is validated by its simulations and experimental studies. Compared to ECs, non‐electrolytic capacitors (NECs) have the benefit of low cost, small size, and long operating life, which brings high economical advantages to the proposed converter with enhanced voltage conversion performances. [ABSTRACT FROM AUTHOR]

Summary: In this paper, the control design and the performance evaluation of a novel high step‐up converter with an hourglass‐shaped impedance network (HIN) are performed when used as an interface between a photovoltaic (PV) source and a load in a PV system. For optimum energy extraction from the PV source, the PV voltage controller design and optimization to track the maximum power point of the PV system is addressed. The converter offers the possibility of an optimum regulation of the PV voltage with voltage mode control using a simple Type‐III compensation network resulting in a low overshoot, a relatively short settling time, and negligible energy loss after a change of input reference due to the maximum power point tracking (MPPT) or to irradiance change. To evaluate the performance of the HIN converter when used in a PV system, PSIM©software is used to perform numerical simulations using the switched model under different conditions. [ABSTRACT FROM AUTHOR]

Output voltages of renewable energy sources, such as photovoltaic units and fuel cells, are normally low, and multistage boost converters or single-stage high step-up converters are usually employed to increase the output voltage to be connected to the electric grid. Among all converter technologies, single-stage high-order dc–dc converters with multiple cells have gained significant popularity in recent years due to their high power density, low cost, and high efficiency. With an increased number of cells, the number of switching variables and dynamic components in multicell converters also increases, leading to control difficulties and consequently system malfunction. In order to understand and ensure the controllability of these converter systems, in this article, we establish high-order mathematical models for typical single-stage multicell high-order dc–dc converters and study their controllability using switched linear systems theories. The structure controllability, state controllability, and output controllability of the converters are analyzed in detail based on the proposed mathematical model. The theoretical analysis is substantiated by simulation and experimental verification on the improved four-cell switched-inductor dc–dc converter. The outcome of this article will provide a theoretical framework and useful references for parameter and control designs for high-order converters in practical applications. [ABSTRACT FROM AUTHOR]

This study proposes a generalized voltage pumping module (GVPM) and a GVPM-enabled converter design approach for electric vehicles. The designed GVPM has high flexibility and can be applied to most high step-up converters for extra voltage pumping yet with low component stresses. The proposed GVPM design method is presented, rationalized and analyzed in a generalized structure, which is followed by eight specific application examples, where typical step-up converters are employed to be structurally coupled with the proposed GVPM design approach for design guideline and methodological validation. Through theoretical analyses and experimental verification, the proposed voltage pumping approach is proven to be able to work synergistically with most types of DC-DC converters, demonstrating its advantageous features and wide applicability for voltage pumping of step-up converters. [ABSTRACT FROM AUTHOR]

Most of the image encryption schemes based on chaos have so far employed symmetric key cryptography, which leads to a situation where the key cannot be transmitted in public channels, thus limiting their extended application. Based on the elliptic curve cryptography (ECC), we proposed a public key image encryption method where the hash value derived from the plain image was encrypted by ECC. Furthermore, during image permutation, a novel algorithm based on different-sized block was proposed. The plain image was firstly divided into five planes according to the amount of information contained in different bits: the combination of the low 4 bits, and other four planes of high 4 bits respectively. Second, for different planes, the corresponding method of block partition was followed by the rule that the higher the bit plane, the smaller the size of the partitioned block as a basic unit for permutation. In the diffusion phase, the used hyperchaotic sequences in permutation were applied to improve the efficiency. Lots of experimental simulations and cryptanalyses were implemented in which the NPCR and UACI are 99.6124% and 33.4600% respectively, which all suggested that it can effectively resist statistical analysis attacks and chosen plaintext attacks. [ABSTRACT FROM AUTHOR]

Summary: In this study, a novel high‐step‐up converter is proposed with a new hourglass‐shaped impedance network (HIN). Due to the short lifetime of electrolytic capacitors (ECs), the proposed converter uses nonelectrolytic capacitors (NECs), which however can realize all ECs' features. Besides, the proposed converter has low capacitor voltage stresses, ensuring it could be electrolytic‐capacitors‐free. With this feature, the proposed high step‐up converter has smaller size, lighter weight, smaller parasitic resistance, and longer operation life than the conventional ones with ECs. In this paper, detailed operational principle and performance of the proposed converter are presented, to demonstrate its advanced features. Simulation and experimental studies are also carried out, which validate the feasibility and effectiveness of the proposed converter. [ABSTRACT FROM AUTHOR]

The isolated bidirectional dc/dc converter (IBdc) plays an important role in dc buses connection, voltage conversion, electrical isolation, and bidirectional power transmission for dc distribution networks. In this article, a multiple modular IBdc scheme based on hybrid dual-active-bridge (HDAB) for medium-voltage and high-voltage dc distribution network is proposed. In proposed HDAB, the switches in upper position of full-bridge are replaced by the half-bridge submodules, and the proposed HDAB maintains the advantages of conventional DAB and achieves bidirectional fault handling capability, avoiding the application of large dc-link capacitors and dc circuit breakers, thus reducing the volume and construction cost. Besides, a high-frequency-link (HFL) voltage regulation strategy is also proposed in this article, adjusting the HFL voltages in HDAB to match HFL transformer voltage ratio adaptively, thus improving the efficiency and applicability of IBdc under the fluctuation of power flow and dc bus voltage. The topology, operation principle, control structure, and corresponding bidirectional fault handling and HFL voltage regulation strategy of the proposed IBdc scheme are investigated. The experimental results verify correctness and effectiveness of proposed scheme and control strategy, promoting the adaptability and practicality for both IBdc and dc distribution network. [ABSTRACT FROM AUTHOR]

In this article, we propose an enhanced one-cycle control (EOCC) strategy for high-voltage gain multicell converters, aiming to resolve the existing issues that exist in the conventional one-cycle control techniques, such as intolerance to load disturbances and inapplicability to multicell converters. The proposed EOCC method is able to overcome these limitations while effectively suppressing input voltage fluctuations and having great responsiveness. Simulation and experimentation on an improved four-cell switched inductor with the proposed EOCC are conducted, which agree well with the theoretical analyses and demonstrate a range of favorable features of the EOCC method, revealing its great feasibility and wide applicability. [ABSTRACT FROM AUTHOR]

This study proposes a novel non-inverting buck–boost converter topology with extra-wide operational zones under both continuous current mode (CCM) and discontinuous current mode (DCM), by introducing a four-mode modulation (4MM) strategy. The proposed 4MM method is able to eliminate the operation dead zone, thus extending the operation zones of the buck–boost converter to contain boost mode, extended boost mode, extended buck mode, and buck mode. Rigorous analyses and design principles are presented in detail to demonstrate the four-mode function through CCM and DCM operational investigations and illustrations. Theoretical analyses and parameter design are verified by software simulation and hardware experimentation in this study, which validates the proposed 4MM method and the functionality of the proposed 4MM-based buck–boost converter. They clearly indicate the superiority of the proposed 4MM-based four-switch non-inverting buck–boost converter over its conventional counterparts, posing wide applicability in industrial practices. [ABSTRACT FROM AUTHOR]

The intermittency of renewable energy sources, i.e., photovoltaic cells and wind power causes problems such as unreliability, harmonic pollution, unpredictability and inefficiency, which pose a great challenge for constructing a reliable modern microgrid. To address these problems, in this paper, we propose a novel structure of microgrid, where sensitive loads, non-sensitive loads and the concept of “load follows demand” are adopted and incorporated. Within the designed microgrid, energy storage systems (ESSs) are coupled with the non-sensitive loads to achieve the supply/demand balance. In addition, a particle swarm optimization (PSO)-based collective load control is employed in this study to create pure resistiveness and piecewise constant active power features in the microgrid, in order to resolve harmonics and unpredictability problems. The proposed microgrid experimental platform is established based on real-time (RT)-lab and dSPACE in a hardware-in-the-loop (HIL) environment, where the efficacy of the proposed microgrid structure is verified in both islanded mode and grid-connected mode, which is able to achieve nearly 100% utilization rate of the intermittent solar energy, piecewise constant power and unity power factor. The proposed microgrid structure and established testing environment also have the potential to be scaled up to multi-microgrid power systems for advanced and wider applicability. [ABSTRACT FROM AUTHOR]

Summary: Boost converters have been widely employed in industrial applications, and cascading boost converters is a mature technique to realize ultrahigh voltage gains. However, the cascade structure inevitably increases the voltage stress of buffer capacitors, resulting in high costs and low energy efficiency. Targeting this issue, in this study, we propose a novel extendable single‐switch n‐cell boost converter (ESSnB), which utilizes the same number of components as the conventional positive output boost converter, but has lower buffer voltage stresses. Simulation and experimentation are conducted in this study, which verify the effectiveness and superiority of the proposed ESSnB over conventional boost converters. [ABSTRACT FROM AUTHOR]