Switched-capacitors as local converters for snake PV modules : a cost/efficiency exploration

In order to reduce the negative effect of partial shading and other sources of current mismatch within a module, smart reconfigurable modules allow altering the connections between groups of cells (cell-strings). With a proper algorithm managing these connections, we can make sure that the majority of the cells are operating close to their MPP, even when a part of the module is shaded. Such a smart reconfigurable module consists of some extra components. Switches are needed to change the interconnection scheme. Small, local converters collect power from multiple cell-strings. They step-up the voltage to reduce the current on the central bus they are connected to. At the end where we connect to the string-level bus, a module converter further regulates the voltage for the grid or the PV array. This topology was presented before where we showed that a smart reconfigurable module could recover up to 70% of the power lost to partial shading. In this paper we take a closer look at the local DC-DC converter. More precisely, we present a cost-efficiency analysis of different converter topologies. Taking into account practical limitations (economical limitations, number of components, maximum switch currents, maximum capacitance values, etc..) we estimate efficiency and projected cost. We show that Dickson pump (CR3) with 30-35mOhm switches is the best candidate. This would result in a chip cost of about €1.

Poly(thioether) vitrimers via transalkylation of trialkylsulfonium salts

Vitrimers are permanently cross-linked organic polymers that can be reshaped, molded, and recycled without loss of network integrity. Herein, we report poly(thioether) networks, prepared through a straightforward thiol-ene photopolymerization, that can be turned into catalyst-free vitrimer materials by partial alkylation of the thioethers (1-10%) to the corresponding trialkylsulfonium salts. Based on a classical S(N)2-type substitution, the resulting polyionic networks can be reshaped upon heating via swift transalkylation reactions. This novel exchange reaction for the design of vitrimers was studied both on low MW model compounds as well as on a material level. In addition, we demonstrated the recycling of these networks without significant loss of mechanical properties

EPICURE: A partitioning and co-design framework for reconfigurable computing

This paper presents a new design methodology able to bridge the gap between an abstract specification and a heterogeneous reconfigurable architecture. The EPICURE contribution is the result of a joint study on abstraction/refinement methods and a smart reconfigurable architecture within the formal Esterel design tools suite. The original points of this work are: (i) a generic HW/SW interface model, (ii) a specification methodology that handles the control, and includes efficient verification and HW/SW synthesis capabilities, (iii) a method for parallelism exploration based on abstract resources/performance estimation expressed in terms of area/delay tradeoffs, (iv) a HW/SW partitioning approach that refines the specification into explicit HW configurations and the associated SW control. The EPICURE framework shows how a cooperation of complementary methodologies and CAD tools associated with a relevant architecture can signficantly improve the designer productivity, especially in the context of reconfigurable architectures

Switch for the optimization of module power by reconfiguration of all strings (SOMBRA) : an insulated integrated switch for a reconfigurable solar panel

The energy yield of a solar panel can be severely impacted by partial shading. Shade caused by nearby static objects can hardly be avoided in installations such as building-applied or building-integrated photovoltaics. Smart reconfigurable photovoltaics (PV) panels are able to change their intra-module configuration to reduce this impact: small substrings can be rewired to be connected in a more optimal configuration. To achieve this, a reconfiguration switch needs to be designed. In this paper a switch for the optimization of module power by reconfiguration of all strings (SOMBRA), a smart switch, is presented. SOMBRA is a fully integrated, low-ohmic switch, designed for currents up to 10 A. It is fully floating up to 50 V, while still being able to communicate with a central unit as an inter-integrated circuit ((IC)-C-2) slave. Two versions were realized, SOMBRA-LV10 for low voltages (LV) and a load current of 10 A, and SOMBRA-HV05 for high voltages (HV) and a load current of 5 A. Measurements proved these devices to be functional, measuring an on-resistance of 1.3 m Omega for SOMBRA-LV10 and 7.3 m Omega for SOMBRA-HV05. This paper will elaborate on the operation, design, and implementation of SOMRBA, as well as the first tests with a small reconfigurable PV module

Two-Element MIMO Crack Finger Microstrip Antenna for Hand-Held Devices

in this paper, we studied the effect of mutual coupling between MIMO antennas and a method is proposed to reduce it between 2-element micro-strip MIMO antenna systems for handheld devices. To reduce mutual coupling between the MIMO antenna element a separate ground plane is designed and the two elements are positioned on the edges of the 2-element MIMO antenna system. A novel idea defined in order to reduce mutual coupling between the closely spaced micro-strip patch elements is adding finger shapes at the edge of each patch antenna to design a new crack finger micro-strip the fingers generate capacitance in between which improved the matching between the patch and the Micro-strip transmission line as well as the mutual coupling reduced from -25 dB to -40 dB. The simulation results showed that the 2-element MIMO system covered the frequency of 2.4 GHz, and the gain and directivity are 6.149 dB and 4.399All the simulations were carried out in CST Microwave Studio

Dynamic covalent chemistry in polymer networks : a mechanistic perspective

The incorporation of dynamic covalent linkages within and between polymer chains brings new properties to classical thermosetting polymer formulations, in particular in terms of thermal responses, processing options and intrinsic recycling abilities. Thus, in recent years, there has been a rapidly growing interest in the design and synthesis of monomers and cross-linkers that can be used as robust but at the same time reactive organic building blocks for dynamic polymer networks. In this perspective, a selection of such chemistries is highlighted, with a particular focus on the reaction mechanisms of molecular network rearrangements, and on how various mechanistic profiles can be related to the mechanical and physicochemical properties of polymer materials, in particular in relation with vitrimers, the recently defined third category of polymer materials. The recent advances in this area are not only expected to help direct promising emerging polymer applications, but also point towards the need for a better fundamental understanding of chemical reactivity within a macromolecular context

IoT Based Smart Manufacturing system-Case Studies

Manufacturing now a days growing and becoming more complex, automated and computerized. Smart manufacturing is an emerging form of production manufacturing asset of today and in the future with involvement of smart sensors, actuators, communication technology, smart consumer devices like smart phones and tablets and data-intensive modeling. This paper will highlight a review of IoT application in smart manufacturing. Case studies on advanced techniques used in manufacturing industries for different operation such as Monitoring and controlling of smart equipment, IoT based Smart factory connectivity for industries, Hazardous Gas Detection, Electromyogram (EMG) monitoring system, and Tool wears characterization, Defect predictive in a manufacturing system, Machinery Health monitoring are presented