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Photovoltaic (PV) systems consist of multiple dc–dc converters, such as a front-end converter for a PV panel and a bidirectional converter for battery regulation. In addition, a differential power processing (DPP) converter is desirably installed to preclude partial-shading issues of the significant reduction in energy yield and the occurrence of multiple maximum power points. This article proposes a novel multiport converter (MPC) based on a switched capacitor converter (SCC) with DPP capability to simplify such PV systems by reducing the converter count. The proposed SCC-MPC is derived from the integration of a noninverting PWM buck–boost converter, SCC, and phase shift (PS) SCC with sharing switches. In addition to the reduced converter count, the proposed MPC achieves reduced circuit volume thanks to the SCC and PS-SCC, both of which are a high power-density converter. The proposed SCC-MPC can regulate the load and battery by PS and PWM controls, respectively, while automatically precluding the partial-shading issues by its DPP capability. The experimental verification using a 200-W prototype demonstrated that the load and battery could be independently regulated with preventing the partial-shading issues.

Mucinous cystic neoplasm (MCN) of the pancreas is a rare cystic tumor occurring in the pancreatic body and tail in young to middle-aged women that is pathologically characterized by an ovarian-like stroma. Chemotherapy for recurrent/advanced pancreatic MCN has been based on chemotherapy regimens for pancreatic ductal adenocarcinoma, but the prognosis is poor. We herein report a 37-year-old woman with pancreatic mucinous cystadenocarcinoma with liver metastasis that responded dramatically to carboplatin plus paclitaxel therapy (CBDCA+PTX). CBDCA+PTX may be a treatment option for recurrent/advanced pancreatic MCN with an ovarian-like stroma.

Various kinds of differential power processing (DPP) converters have been developed to improve the energy yield of partially-shaded photovoltaic (PV) panels by precluding partial shading issues, such as the reduction in power generation and the occurrence of multiple maximum power points. Meanwhile, PV systems require fault diagnosis tools to detect premature deterioration and malfunctions that lead to a reduction in power generation of the system as a whole and, in the worst case, hazardous situations, such as a fire. This article proposes a novel DPP converter as well as an electrical diagnosis technique using the DPP converter. The proposed DPP converter not only addresses the partial shading issues but also provides the electrical diagnosis capability. In the diagnosis mode, the DPP converter injects ac currents to a panel, and an ac impedance of the panel can be calculated from the voltage response to the injected ac currents. The detailed operation analysis and experimental verification tests using a prototype were performed. The results demonstrated the improved power yield from partially shaded PV panels and the electrical diagnosis capability of the proposed DPP converter.

Conventional lithium-ion battery (LIB) packs comprising series-connected modules need cell and module equalizers separately, resulting in increased system complexity. This article proposes a modular equalization system using dual phase-shift (DPS)-controlled capacitively isolated dual active bridge (CIDAB) converters. Each module contains an intramodule CIDAB converter that performs direct cell-to-cell equalization. Meanwhile, switching legs of adjacent modules’ CIDAB converters are connected through an LC tank to configure an intermodule CIDAB converter that equalizes module voltages. The switching legs of CIDAB converters are utilized for both the intra- and intermodule equalizers, achieving the simplified system. Based on the proposed DPS control, the PS angles of both the intra- and intermodule CIDAB converters are manipulated to perform cell and module equalization. The prototype of the proposed modular equalization system for two LIB modules, each consisting of 12 cells was built and tested. Cells and module voltages in the proposed system were sufficiently equalized, demonstrating the efficacy of the proposed equalization system.

Conventional supercapacitor (SC)-based energy storage systems require two separate converters, namely a bidirectional converter and a cell voltage equalizer. Each converter requires magnetic components, hence increasing the complexity, volume, and cost. This article proposes the single-magnetic bidirectional converter integrating a cell voltage equalizer. The proposed integrated converter is derived from the combination of a bidirectional pulsewidth modulation converter with a tapped inductor (TI) and a resonant voltage multiplier (RVM). The RVM is driven by the TI generating a square wave voltage with an arbitrary amplitude. Not only is the system simplified by the integration, but also the single-magnetic topology achieves circuit miniaturization. A 100-W prototype for nine SCs connected in series was built for the experimental charge–discharge cycling test. The voltage mismatch of SCs automatically disappeared during charge–discharge cycling, demonstrating the integrated functions of the proposed converter.

In photovoltaic (PV) panels consisting of multiple substrings connected in series, mismatch in substring characteristics due to partial shading causes the significant reduction in energy yield and the occurrence of multiple maximum power points. In solar roofs of plug-in hybrid electric vehicles (PHEVs), substring characteristics are always unavoidably mismatched due to the curvature of solar roofs, resulting in the mismatch issues similar to partial shading. Various kinds of differential power processing (DPP) converters have been proposed to preclude mismatch issues in traditional flat PV panels. The key contributions and novelties of this paper are summarized as follows. Firstly, uneven irradiance on the solar roof of Prius PHEVs is investigated. Secondly, existing DPP converter architectures are reviewed to select a proper DPP converter topology for PHEV applications. Thirdly, the selected topology is improved to be better suitable for PHEV applications, followed by the detailed operation analysis. Lastly, the experimental results of the laboratory and field testing using a prototype are presented. Field testing using an actual solar roof of Prius PHEV was performed, and the results demonstrated the daily energy yield enhancement of 4%–5% by the proposed DPP converter.

Three-port converters (TPCs) combining two dc–dc converters into a single unit is a promising solution that can simplify and miniaturize satellite electrical power systems. Conventional nonisolated TPCs, however, face a variety of challenges, such as the necessity of a transformer, low effective duty cycle operation, and unshared ground issues. This article proposes a novel nonisolated TPC integrating a unidirectional and bidirectional pulsewidth modulation converters. The two converters can be integrated into a single unit with reducing total switch count without employing a transformer, thus achieving the simplified circuit. In addition, thanks to the capacitor added in series with switches, not only the voltage stress of semiconductor devices is reduced, but also miniaturized inductor design is feasible. The quantitative analysis revealed that the volume of passive components in the proposed TPC could be reduced by approximately 19% compared with a conventional nonisolated TPC. A 240-W prototype was built for the experimental verification, and the results agreed well with those of the analysis, demonstrating its efficacy.

This article presents a modular equalization system integrating module- and cell-level voltage equalizers for energy storage systems consisting of series-connected modules, each comprising multiple cells connected in series. Star-connected phase-shift switched capacitor converters (PS-SCCs) and tapped-inductor-based resonant voltage multiplier (TI-RVM) are employed as a module- and cell-level equalizers, respectively. The module- and cell-level equalizers are integrated with sharing active switches, hence halving the total switch count and achieving reduced system cost and complexity in comparison with conventional systems. In addition, equalization currents in both the PS-SCC and TI-RVM can be inherently constant regardless of voltage imbalance conditions, offering intrinsic current limitation capability at both the module and cell levels. An experimental equalization test was performed using the prototype for five electric double-layer capacitor modules, each containing six cells connected in series. Module and cell voltages were equalized at different rates, and voltage imbalance was eventually eliminated even during cycling, demonstrating the equalization performance of the proposed modular equalization system.

Photovoltaic (PV) strings consisting of multiple panels suffer from partial shading or characteristic mismatch issues, such as a significant reduction in power yield. Various kinds of differential power processing (DPP) converters have been developed to prevent the negative impacts of substring-level partial shading. For panel-level applications, however, conventional DPP converters face a variety of challenges, such as impaired extendibility and increased voltage stress of circuit elements. This paper proposes a switched capacitor converter (SCC)-based modular DPP architecture. Modules, each containing series-connected panels with a panel-level DPP converter, are connected through a switchless module-level DPP converter, and PV panel characteristics are unified at module- and panel-levels. The number of panels in each module is fixed, while the number of modules can be arbitrarily extended without redesigning DPP converters, hence offering good modularity. In addition, since voltage stresses of capacitors in the proposed architecture can be reduced lower than half the module voltages, the proposed DPP system realizes all-ceramic-capacitor SCC circuit by properly determining the module voltages. A prototype for eight panels, which were grouped into two modules, was built, and laboratory and field tests were performed. The experimental results demonstrated the enhanced power yield from the partially shaded PV string.

Interleaved converters are a typical solution to enhance a current capacity and to reduce current ripples of an input or output port. Conventional interleaved LLC resonant converters need additional switches and passive components with a feedback control loop for active current balancing, increasing the circuit complexity and cost. This paper proposes a novel three-phase interleaved LLC resonant converter with an automatic capacitive current balancing capability. Two flying capacitors are added to a conventional interleaved LLC resonant converter in order to realize not only the automatic capacitive current balancing but also the reduced switch voltage stresses and asymmetric resonant operations that contribute to reducing rms currents as well as copper losses of transformers. The detailed operation analysis, including the capacitive current balancing mechanism and gain characteristics derivation, are performed. The experimental verification using a 1-kW prototype demonstrated that the automatic capacitive current balancing could be achieved despite the significant mismatch in transformers' parameters.